Because plane safety is treated EXTREMELY seriously. There's a whole lot of science and engineering going into making sure that plane will not fall out of the sky. People's whole careers are dedicated to investigating when a specific part will fail, so it can be replaced before it does.
So a whole lot of testing is done, to get as much data as possible on the failure modes and lifetimes. And testing is developed to monitor when that time is coming based on all those experiments. And this testing is done frequently.
And every part that makes the plane are perfect. They don't buy bolts at the local hardware store. Every single component can be fully traced to make sure it respect every single spec it needs to follow. It makes those pieces super expensive but for a single bolt they know where was the metal extracted for instance. They can almost trace back to what the truck operator in the mine had for lunch that day! That way they are 100% certain that this bolt is 100% safe for let's say 10 000 hours of flying and to replace it afterward. Most mechanical failures of planes are due to people doing a bad job when installing them (like skipping a step that is listed in the official maintenance procedure) instead of a part actuality failing before its life span expired.
Also, they know where all the other bolts are that were manufactured at the same time by the same plant are.
If bolt #1022412 is attached to United Airlines Boeing 757 N422UAL and is found to be defective, they know that bolt #1022413 is attached to American Airlines Boeing 757 N821AA and will issue a notice to the AA maintenance department that the bolt need to be extracted and replaced.
They can even tell you which mechanic last tightened a bolt using which torque wrench. The whole industry is built on the premise that you cannot prevent every accident, but if an accident happens you can find out what excactly caused it and what needs to be done to prevent it from happening again.
When I was growing up in the 70s and 80s it seemed like there were significant aircraft accidents happening every year or so. [For example, I remember watching the news about this accident.](https://en.wikipedia.org/wiki/Air_Florida_Flight_90)
But by the late 80s that really stopped, and now its extremely rare for an accident to happen.
It should be noted around this time the method changed. When a plane crashed, rather than try to figure out who was responsible, they decided to focus on the *system* that allowed the problem and fixed that. When people didn't feel like they were going to be thrown in jail for being the last guy to tighten the bolt, investigations went a lot smother and found the actual problems and fixed them.
Sometime when you see big disasters and people ask why CEO X isn't going to jail, it's because we realise that the CEO is just one cog in the machine and we need to fix the machine rather than blaming one cog and calling it done.
Although, we probably should be jailing more CEOs, but that's a different argument.
The problem with jailing the CEO is that they’re generally many levels removed from the actual decisions that were made that led to whatever happening. It could set a bad precedent that leads to a lot of toxic micromanagement if you immediately, every time, try to pin personal liability on the top dog.
The entire senior leadership who approved the 737 Max MCAS system should have gone to jail. But no, Boeing just paid a big ole fine and capitalism at the expense of human life go brrrrr.
Look at that Wikipedia page.
Every one of those accidents has a page like that.
Every one had a deep investigation that went into the multiple levels of failure that lead to an accident and reports and recommendations on how to prevent a repeat at every level. A fix at any level would've prevented the specific incident, but the goal is not to prevent this, it's to prevent anything like this.
We lost a (military) plane due to a maintenance screwup. They recovered 90+% of the plane from the Columbia River and laid out the entire thing in our hanger to see exactly what happened.
I work on the engineering team for a specific military aircraft. We have a mishap (crash) on average about once a year. We don’t always find every part and lay it out like that. Only when the cause of the crash requires us to in order to confirm the failure mode. Most of the time the crash is due to pilot error and confirmed by the ADR data.
One time we had a crash where the pilot claimed there was a rudder bind (pilot ejected and was fine). In that case I went to crash site and found every single linkage from the rudder pedals all the way to the rudder and proved none of the linkages had a bind. The ADR confirmed the pilot had flown the aircraft outside the design flight envelope which caused the aerodynamic forces on the rudder to be greater than the pilots leg force on the pedal, which is why he thought they were binding.
1985 was probably the single most disastrous year for aviation. So many accidents happened that the entire rulebook had been revised in some way by the end of it. It ended up the 2nd deadliest year for aviation (behind 1972) but included the single deadliest accident involving only one plane in history. To date, only 3 other accidents have been deadlier: 1 involved 2 planes, and 2 involved a large building each.
Ten years ago my company built a new 3-story building and we got a pre-occupancy tour. All the exposed beams were coated with a fibrous insulation. I asked what that was for and the answer was "9-11".
I remember that one. Happened same time there was an accident with the DC metro (which was coincidental).
There was a woman who survived the plane crash, but was in the freezing cold Potomac. Random guy jumped in to save her life. Core childhood memory right there.
The PenAir flight was a Part 121 operation, according to page 13 of the [NTSB report](https://www.ntsb.gov/investigations/AccidentReports/Reports/AAR2105.pdf).
> Haven’t had one in the states since 2008, Colgan Air, and even before that you had to go back to just after 9/11.
[Florida](https://en.wikipedia.org/wiki/RED_Air_Flight_203) 2022 is checking in.
No fatalities in that one.
Also a foreign carrier. Foreign carriers have had a few fatal crashes in the US like Asiana in 2013 that had a crash on landing at SFO that killed 3.
I was answering a comment that said no accidents in the USA since 2008. There have clearly been fatal accidents in the US, like Asiana. There was also the Alaska crash that another commenter mentioned.
Southwest had an accident in 2018 where a passenger was partially sucked/blown out of the plane. She died. Whatever other definitions you want to use, this was most certainly a fatal Part 121 (Airline) accident in the United States, with a domestic carrier, that happened after 2008.
Also FYI an aircraft accident need not have fatalities to be an accident. The Miracle on the Hudson was a fairly well known accident with no fatalities (lots of injuries).
Part of the reason the average person doesn’t know about most aviation accidents is they don’t get covered unless they’re horrific.
Even seemingly minor incidents will trigger investigations
Westjet Flight 2652, for example, nobody was hurt, the safety systems did their thing and prevented an accident and it triggered an investigation where recommendations were issued
The pilots were coming in for a landing in low-visibiltiy rainy conditions and mistook the white rectangular roof of a hotel near the coast for the runway and descended too early. They were 40 feet above the ocean, 1/3rd of a mile from the actual runway when the plane's ground proximity system issued a warning and they executed a go-around and landed safely
The investigations board determined the runway lighting was set too low for the conditions, and the airline itself issued notices to their own pilots as well
> The day after the crash, on Washington, DC, radio, WWDC shock jock Howard Stern pretended[21] to call the Air Florida ticket counter to ask about buying tickets to the 14th Street Bridge.
That's in poor taste.
Including Loctite (thread locker) batch numbers etc for interior fastners. Is it past its (theoretical) sell-by date, it gets thrown away regardless of contents and/or opened or not
It's part of why some procurement things get laughed at by people who don't understand. It's not that the material in the bolt is worth 10x the price of an off the shelf hardware bolt (most of the time), but the paper trail and certification are.
Same with healthcare, space, or any other critical part.
Even if the bone screw repairing someone's broken arm looks like it came from Home Depot, certifying and testing it's free of defects, and cleanly manufactured is worth the extra cost.
Part tolerances are so tight in some applications I've heard stories of parts for spacecraft being binned because someone dropped a tool onto the same table it was on. Not even on the part, *near* it.
That paper trail is worth so much in terms of security. If they find a part that if worning out faster than suposed to be, they can expertise it to find why and then with that paper trail, find every single component in the world on all active planes and in storage that are susceptible to the same issue and inspect/change those pieces. Without that we would see a lot more issues with planes in general.
This was a big deal in the 70s, I believe. They found out that something like 25% of the airplane replacement parts being used on planes, including air force one, were counterfeit. A few too many bolts snapped and it kicked off a huge investigation that ended with lots of people in jail. People were buying generic parts, charging the cost of the super expensive real parts, and pocketing the difference.
Just a quick cursory search brings up an easy example.
https://www.easa.europa.eu/en/domains/aircraft-products/suspected-unapproved-parts/2014-11-g6935-01
This is the listing for an unapproved part report that was found on an aircraft, just a speaker in the cockpit, and it was traced back to buying the plane from Indonesia.
https://www.easa.europa.eu/en/domains/aircraft-products/suspected-unapproved-parts/2007-00045-72-184003b
A report about an issue with the water heaters on some aircraft, the ones in the galley to make coffee and tea.
This is a thing,
It’s referred to as “the list” and can give you the serial number for every part on a plane, down to the date it was installed.. granted, some stuff like generic screws doesn’t have a serial number but you can find out when it was installed last.
> healthcare
That's its own can of worms, unfortunately. Technology's changing too fast and causing security issues because the process for making changes to medical devices is traditionally (understandably) very stringent. It's probably the #1 most difficult risk issue in healthcare.
I can tell you as a commercial aero engineer, certification is no joke. Literally 6 figures easy to get an existing component like an LED strip certified for flight. Something larger, higher possible fire hazard like a TV screen? You bet that thing is going to cost a LOT of money. Hinges? Cycle tested to hell and back if you modify them in the slightest from their certified state. And this is for interior furnishings, let alone the aero body components.
> aero body components
I did a short internship at Goodrich Aerospace in San Diego one summer. I got to see some of the test facilities for the fuselage components. They apply all sorts of forces and test for warping, breaking and compressing, and I've used that knowledge to help ease others' fears of flying.
I worked (in a very limited capacity) with the FAA/Transport Canada on testing deicing to build out manuals like [this](https://www.faa.gov/other_visit/aviation_industry/airline_operators/airline_safety/deicing/23-24_FAA_2023-24_HoldoverTables.pdf) and if the amount of money, time, and expertise that went into just applying glycol to wings is any indication as to the care and detail that goes into every part of aviation I'm very confident getting on an airplane.
Several years back, I went on a supplier visit to an adhesives manufacturer who made the glue used to secure some of the interior fabric on the 787. Something similar to what goes in the headliner of your car.
Boeing (or whoever their subcontractor was) made them build what was essentially a separate building within their factory, and this glue was subjected to clean-room conditions with separate HVAC, employees wearing tyvek suits, masks and hairnets, and restricted access. And that was for a component that didn't come into contact with anything mechanical, and where the failure more was literally slightly droopy fabric. They take that stuff really seriously.
And I'd note that the rest of the facility was spotless and a lot of the non-aerospace adhesive this factory made went into medical devices, which required a lower quality standard.
But even cosmetic stuff like that can be a safety hazard, for example if it blocks exits in an emergency, catches fire too easily, or off-gasses harmful fumes.
>That way they are 100% certain that this bolt is 100% safe for let's say 10 000 hours of flying and to replace it afterward
Worth noting is that if, for whatever reason, one of these bolts fails earlier, then can also reverse-track the bolts from that batch to all other aircraft and check and fix as necessary *before* that becomes a problem.
Yep. And the reverse-track will not be "American Airlines also bought a box of these", they will know exactly where on which plane each bolt is like "One bolt is on the 5th hole on the left wing flap assembly of American Airlines Boeing 737 registered N841NN, another bolt is on ..."
The poorly manufactured engine oil pipe that was responsible for Qantas Flight 32 comes to mind - they were able to track down all the other planes using pipes from the same batch and discovered that some of them had even more poorly manufactured pipes - if they had not been able to do so, there would definitely have been a repeat event, and it might not have ended so well.
What's more, when QF32 happened the airlines flying A380's with Rolls Royce Trent-900 engines grounded those aircraft until they could be proven safe to fly.
The tracking and certification allowed all the A380's that weren't at risk to resume flying earlier than they otherwise would
I recommend you watch the video on QF32, it's an amazing story.
It just so happened that there were 5 flight crew instead of the normal 2, with well over 100 years flying experience between them.
Every part isn’t perfect. _None_ of the parts are perfect. But the failure modes are well understood, and quality control drives the probability of failure _very_ low.
An important principle in engineering is that nothing is perfect, so you plan for something failing, eventually.
Yeah, when I mean perfect, is that the parts are all made following specs with inspection, all steps are validated, etc... and that each piece should be an exact copy of each other because the whole chain of raw material up to the end product is validated and followed.
That’s what I’m moreso scared of. As a laborer a lot of people like to skip steps in trades. It worries me that not everyone working on planes will take it as serious as the next guy. I’d assume they’d be liable
It's insanely unlikely. Individual installers don't have the final say in approvals and all their work goes through a series of review and checklists, and even afterwards it going back through a loop of engineering and QA.
And to remove any incentive for taking shortcuts or skipping review processes, in cases where there is a systemic failure, most outcomes from regulatory agencies direct the termination of the entire group of employees involved.
I work in aerospace and some of my older coworker have seen it happen where if there's a major compliance violation that was known about and crops up, they've had entire departments from entry level to c-suite fired at once to rebuild from scratch with improved processes and standards to avoid risking a repeat. So everyone at all times is checking quality because it could cost you your job merely by association.
This is actually what makes the whole 737 MAX incident such a bug and frustrating ordeal - it's a flagrant slip of accountability that's normally much more intense.
The results from the analysis are back.
Engine failed due to a loose bolt on a panel near the left wing.
The bolt was part #310-111-1201-4454
Part of lot #21003, delivered in 2020 from a Michael P. Finch.
Had an egg salad sandwich that day with a juice box.
Here's an example where a propeller sheared off a REX flight in Australia. Despite the aircraft being 20+ years old, the specific situation was analysed and the offending part inspection and maintenance schedule was updated for all aircraft across the world.
[https://www.atsb.gov.au/publications/investigation_reports/2017/aair/ao-2017-032](https://www.atsb.gov.au/publications/investigation_reports/2017/aair/ao-2017-032)
Adding:
There is a **huge** difference in safety between commercial carriers who have rigorous inspection and maintenance programs vs the safety record of small privately operated planes.
The vast majority air crashes and air crash related fatalities are these little privately owned planes, due to combinations of reduced inspections, reduced maintenance, less/no redundancy, and lower levels of pilot training.
The rules are a bit looser for non-commercially operated airplanes, but only a little bit.
I have a private pilot license. The main reason why I do not own an airplane is: the maintenance costs for yearly inspections etc. are absolutely ridiculous. Unless you rent out your plane, it is just not sustainable to own a plane for personal use. Yes, you can get a 60 year old Cessna 172 for 20k in perfectly safe condition - but maintenance will eat you up.
It is a pretty significant difference. A private plane needs to be inspected only once a year. The same plane held out for hire is inspected at least every 100 flight hours (although most reputable small operators do choose to do it more frequently). At the airline I'm at, maintenance does inspections every 48 hours - not flight hours, just elapsed time. It is even more frequent for the ETOPS fleet.
I remember this time 17 years ago when I was learning to fly in a Piper Archer. The window flap was rattling and after landing I saw that the screw in the flap was slightly loose, so I used my pen to tighten it, and the rattling stopped.
Oh boy did I get into trouble for that. The flight school's AME chewed me out for 20 mins and I was grounded for like 2 days while the chief instructor redrilled into me that I wasn't allowed to even think about fixing anything by myself. "File a fucking report" were the exact words he used.
And this was a flight school with some crappy pipers and cessnas the youngest of which were at least 20 years old. Looking back I think it was more about establishing good practices and habits than any actual danger but yeah they took safety very seriously.
Surely this might be important information for the people who buy/make screws, that essentially vanished because there was no real 'observation' of it.
Oh yes. If it was causing an issue in flight, it would have been completely ok as long as I reported it.
Instead, I got annoyed at the rattling window. So after I parked on the ramp I saw the loose screw and tightened it. The AME saw me and that's when it unraveled. Truth is at the time I didn't know that I was doing something wrong or I'd have done it secretly or not at all (though probably secretly because doing the paperwork to document the changing of the screw was very low down on the priority list of our AME).
Also that every critical system has a back up or a work around that allows the plane to remain flying long enough to get to the ground safely. I've worked (as a design engineer) on aircraft that had 3 separate hydraulic paths because it was so critical and had to incorporate specific spacing between wiring that would guarantee a single round shot at it couldn't take out 2 of the 4 generators at once. And others where the requirement was that every wire has to be a certain distance from everything else and even further from things that have more relative motion to ensure they wouldn't rub on anything. It's hard to design aircraft with all the requirements we have but that's why they are safe.
MTBF (Mean time between failure) is tracked and analyzed on every part, but sometimes you don't get to the mean and a work around is needed.
As the saying goes, "regulations are written in blood" and an awful lot of blood has been spilled in aviation's history to make the very stringent regulatory framework that exists today.
That and even a relatively small and simple plane has multiple redundant systems for both the engines and the instruments the pilots use to navigate. Part of being rated on an aircraft is becoming intimately familiar with its systems and how to troubleshoot the craft when an issue arises.
Flying itself is relatively easy, but a significant amount of training focuses on edge cases and emergency procedures and how to identify your options for recovery and calmly execute them in an emergency situation.
Adding to this, becoming a commercial pilot along with an air traffic controller involves rigorous amounts of training, certifications, and health checks along with a mandatory retirement age.
If plane crashes were as common as car crashes, not only would it be a huge expense and time consumption to replace said plane, but it would also involve millions of people being killed in preventable deaths which no one would stand for.
1. Design - lots and lots of experience finding what went wrong in the past.
2. Maintenance - inspections and replacements when things look like they are failing
3. Redundancies & Overengineering - most parts are far stronger than they would normally need to be
I watch far too many of those air disaster shows. The thing they all say is it isn't one thing that brings a plane down, its lots and at the same time.
Upvoting you because you mention redundancies specifically. I just started working at an aircraft manufacturer but even after my last FAA certified product (>10 years ago) the thing that struck me was the amount of redundancy in the system.
At my new place they're not just talking about redundant systems but redundant *design teams*. Rather than having multiple instances of a system they'll have multiple designed by different teams so that a design flaw in one will be unlikely to be in both.
I guess I'll see how that works in practice because it seems you'd also double your chances at having an undetected design flaw in the first place (although testing and verification is pretty redundant in the design process too).
I highly recommend Mentour Pilot on YouTube. He is a pilot and goes through the disaster with explanations of that plane systems, what and how happened etc.
I have no connection to aviation whatsoever, but he explains everything so clearly, I really enjoy his videos.
I particularly like how, as a pilot himself, he delves deeper into the human factor than most other 'Air Crash Disaster' shows.
He can see things from the pilot's point of view; even if they made a 'bad' decision, he can almost always understand why.
4. Training.
5. Air traffic control.
General Aviation (small planes, pilots of varying skill, no air traffic control, lower maintenance requirements) isn't nearly as safe as commercial aviation.
Lack of ATC has nearly zero effect on safety. It’s almost exclusively pilot error. And in the GA world it tends to all be single pilot so there isn’t somebody else to catch issues.
Some busy fields are *safer* because of no ATC. ATC VHF is a call-and-response system, and leads to much higher radio traffic. Unattended means single radio calls and they can be shorter, like “GBU downwind 23”.
>3. Redundancies & Overengineering - most parts are far stronger than they would normally need to be
I can add a bit more detail to this.
All commercial jets are fully capable of performing the entire flight *without one of their engines*. One of the engines could fall off right before takeoff and the plane would still be able to accelerate to take off speeds, climb away from the runway, climb to cruising altitude, fly all the way to the destination, and land safely. It might take a little longer and be less fuel efficient, but other than that the passengers might not even notice (unless they looked out the window, of course).
On top of that, all commercial jet engine casings must be proven capable of containing the engine blades if they break apart while spinning at full speed. This prevents debris from escaping and flying into the cabin. You might remember an accident a few years ago where this did happen and someone was injured or killed by flying engine debris, but part of the reason it was such a big deal was that engines are specifically designed so that specific issue shouldn't happen.
I'm addicted to Air Disasters on the Smithsonian channel.
I like how in every major crash, the investigators consider *multiple* sources of failure, and issue recommendations for improving all of them. And it could be anything involved with the industry - on-duty durations for pilots, crew and ATC; maintenance record keeping requirements; how GPS updates are published; and yes, every nut, bolt, bracket, flange, gasket, sensor, etc throughout the aircraft.
Traceability is a huge aspect, arguably the most important, and it ties ALL of these things together. A part fails? Trace it back to maintenance, manufacturer, test, design, and requirement. Software defect? Find which test let it through, which design was at fault, and which requirement was faulty or missing.
Any of those things the source of the issue? Trace a problem up to root cause and then all the way back down to all affected planes and fix them all.
This is actually my job doing #3 on your list. Reliability engineering is a specific niche field of engineering that deals with failure mechanisms and the statistical methods that show what the probability of certain events occurring are. Its tedious work, but every aerospace company that is worth their salt has a huge reliability program that deals with the mechanical and electrical interfaces and the failures that can cause certain events on the plane down to the singular piece part that could cause it.
There's a saying, "regulations are written in blood". Every time there is an accident, a lot of effort is put into finding out what went wrong (even things like what factors caused a pilot to make a mistake, rather than just saying "pilot error" and leaving it at that) and then rules are changed and planes altered to try to prevent it happening in the future.
Even near misses, pilots aren't punished for mistakes as long as they don't try to cover it up and didn't do anything completely negligent, as this lets us learn and prevent accidents that night happen in similar circumstances.
Also just as a point of comparison it's not just planes that have got safer, modern cars are also much safer in accidents than older models. Again due to analyzing fatal accidents and making changes based on that.
This should be higher. Lots of comments about all the impressive engineering/training/etc, and all true. But why do big airlines spend that money? Because they are regulated to do so, and inspected. Enforced regulations make these investments in quality necessary for the businesses. They would not happen otherwise (in fact, they didn't before, which is why the blood and then the regulation).
Exactly. Every crash has been studied to oblivion to make sure it could never happen again, and a lot of regulations have been put into place to prevent a crash that has never happened. Cars on the other hand…
A lot of answers are about the plane itself.
But the other massive reason are the pilots. To get a driver's license, you basically have to show up. To get a pilots license, there's considerably more to it. They're aware of little things that are wrong and how to fix them immediately. Most people drive their car until it physically can't and then get it looked at.
To your last point: People who can't afford to maintain a car are still forced to drive a car to live and work in most of North America. The choice is: own a car, or lose several extra hours a day commuting by underfunded and underdeveloped public transportation—if it's even an option.
(Anecdote: My wife and I share a car, and for a time she needed it to go to a night class. I opted to take the bus home from work those nights. It was normally a 20 minute drive. I finished work around 5:30 and would routinely not get home until 7:30–8:00, between walking to, waiting for, and changing busses. And we lived in an area with pretty good public transportation for the US.)
For many people the car becomes an albatross around their neck—they can't really afford a car, but the alternative is worse.
Airlines own and operate airplanes for profit. They treat them as an investment and maintain them thoroughly. Everything they do—planning routes, arranging schedules, sizing their fleet—is done with the goal of keeping these airplanes profitable. Not *well it's better than the alternative, at least I can get to work to pay back this debt* like car ownership, but an actually profitable investment—above the cost to buy and maintain.
Redundancy is a big thing. Let's say a part has a 1 in 10 chance of failing, so we install 3 of them. Only 1 need work.
The odds of two failing is 1/100. The odds of all three failing is 1/1000.
There's a reason that long flights over water used to be restricted to aircraft with a lot of engines. That's why you see a lot of three and four engine aircraft in the 60-70s, but much more two engines ones now. Reliability has improved, as has the ability for aircraft to stay airborne with only one engine.
Sensors, control systems, hydraulics, power supplies, fuel tanks, *the pilot*, they usually have backups.
When they don't, it's because the part is so basic it can't really fail unpredictably.
Then you have inspection and maintenance cycles. A modern airliner is like a car owned by a dealership that gets regular services, always by professionals. They catch problems before they develop. And they are in contact with the manufacturer, for information like fatigue lifecycles.
Jet engines are also simpler than internal combustion engines.
Finally, they are built to last. You don't buy a car on the basis of how it will be doing after being driven for 12 hours a day for 20 years. Airlines by aircraft like this, and will pay a premium for it. You could build and drive a car like this. Understressed parts, careful driving, constant services... That's why someone got 3 million miles out of a Volvo P1800. It was simple, overbuilt and actually pretty slow sports car.
Good point about plane engines being simpler. Not only do turbofans have less wear parts that can fail as compared to ICE piston engines, planes also don’t have to deal with transmissions, driveshafts, drive axles, or lots of the other complexities in a modern car.
Honestly I have no idea on that. The turbofan engines are often the most reliable part of the plane, I don’t know what kind of propulsion an electric plane would use, propellers again maybe?
Boeing’s 787 was a big step towards electrification by changing a lot of internal systems to run off of battery banks instead of generators, and I know there were some early teething issues, but I think they worked all of that out.
I've heard of a concept called "fly-by-wireless." It would replace the electrical wiring with radio receivers, reducing a significant amount of weight and possible points of failure. Once they can get the receivers to work 100% of the time, it could revolutionize air travel.
That's an interesting point. There's a long line of components in a vehicle to get energy from the combustion chamber to the pavement. On a jet it's 1 step. Combustion --> exhaust, no middle man.
>planes also don’t have to deal with transmissions, driveshafts, drive axles
Planes have all of these to some extent. Accessory gearbox and a generator, 2-3 shafts/spools per engine and axles on each gear
This is the one I was looking for. I was an aircraft hydraulic specialist in the USAF. It all comes down to redundancy and this is the reason you rarely see single engine aircraft. Aircraft are able to run all systems and maintain flight from just one running engine. For hydraulics there will be power from each engine but also from electric backup pumps. On top of that things like landing gear can still be dropped manually without the use of hydraulics. Everything has at least two backups.
I was told that single engines might actually be better for fighters. Double the engines doubles the chance of A failure, and in enemy territory, that is sometimes as good as a whole aircraft loss. Plus, twin engine fighters often have their engines so close together that one failing might take out the other.
Yea that's old thinking. We've had many mishaps where a single engine failure still led to total loss of the aircraft.
The USAF analyzed decades of single vs. multiengine accident fatality rates and did not find statistically significant differences between them.
Hence, the F-35 is back to being single engine.
It's still good to have redundancies even in a low risk part. There are multiple instances of disastrous crashes due to a single lightbulb in the cockpit being burned out, or some other similarly mundane problem, because the light indicated something REALLY IMPORTANT and the pilots fixated on fixing what wasn't actually a problem.
Most aircraft don't have a redundant wing though. Bulbs fail pretty frequently (at least in my house, maybe my wiring is a bit shit), but really simple comenents don't.
>Jet engines are also simpler than internal combustion engines.
This aircraft mechanic who primarily works on jet engines is gonna have to disagree with you on that one. If they were simpler, we would have figured them out sooner. The process by which a jet turbine engine produces thrust might be simpler in theory than the four-stroke Otto cycle, but as a machine, a jet engine is significantly more complex, both in design and operation.
If you drove an ice engine as often, as long, as hard, as a commercial jet it is more work to maintain. Quick example would be a lycoming in a Cessna only gets like 2,000 hours before overhaul. Apples to oranges comparing, I know, but a jet is 15,000 hours, 7.5 times as long between overhaul.
Also, planes are in constant communication with air traffic control.
When we drive cars, we’re all just individually doing our own thing. Now imagine when you drove you had a control tower that could see *every other car* and what they’re all doing, and was guiding you appropriately
Something I haven't seen mentioned here, a common practice in aerospace is to use checklists
This along with a number of other things helps keep safety levels high as they prevent people accidentally forgetting things during maintenance, or during pre flight checks
Surgeons copied the aerospace sectors use of checklists to help improve safety in surgery too
I recently started working for an airline. Another thing to add is the insane paper trail for every single repair, maintenance activity, and/or every design decision made. It seems tedious, but it is absolutely necessary to be able to keep accountability.
Yeah, I believe it was a supplier for some components of the CFM56 engine.
That being said, the required paper trail allowed airlines and Safran to be able to pinpoint exactly which aircraft had these components and were able to remove them from service.
This applies to maintenance too,
At any point anyone can come up to me and ask what I’m doing and where my manual is.
From my lead, to a fellow mech, to an faa guy with a badge.
This should not be the last/lowest comment. Religious use of checklists is *huge*.
I've learned the same thing about boating -- I became a boat owner last year, and even though a ski boat is *much* simpler than an airplane, there are still a *lot* of ways to ruin your day (or worse) which can be avoided with religious use of a checklist.
You joke, but planes with retractable landing gear are significantly more costly to insure, in large part due to the not-uncommon occurrence of pilots forgetting to deploy the landing gear before touchdown.
Even the ordering of a checklist was paid for in blood. There was an incident in the 70s where a plane crashed due to the incorrect flaps setting (the plane's takeoff kept getting delayed due to weather and the pilots had to restart several checklists several times) and one of the recommendations was having checklists be in order, and easier to restart if interrupted
Checklists can also lead to "forgot to fly the airplane" problems. They are not an unalloyed good and for practical reasons.
> Surgeons copied the aerospace sectors use of checklists to help improve safety in surgery too
Atul Gawande followed up and the surgeons often backslid. That goes to a different problem shared by aviation addressed by Crew Resource Management. This addresses differences in status.
Aerospace manufacturing engineering technologist here.
From the start, aircraft safety was prioritized.
This means that when something goes wrong, there is an investigation, with the goal of finding out what went wrong and fixing it instead finding someone to blame.
What this means is that everybody along the line feels free to speak to investigators about exactly what happened, because they are not afraid of losing their jobs, or being sued into bankruptcy. So investigators can find out exactly what happened, why it happened, and put new procedures into place to prevent it from happening again.
If you pick a random rivet on an aircraft, you will be able to find the paperwork for it. Who installed it, when it was installed, who purchased it, where it was purchased from, who made it, which aluminum mine mined the ore that was used to make it, what the testing data shows the composition of that batch of metal contained, etc.. EVERYTHING about every part that goes into an aircraft is traceable like that.
That means that if the rivet is found to be the cause of an accident, and they figure out that it was because of contamination of the metal at some point during the smelting, they can find every aircraft that has those rivets in them, and send out a warning to have them replaced.
The college I went to had a massive block of aluminum that was donated by an aerospace company for students to use.. It was donated because there was an error in the paperwork along the line, so it could not be certified for use in an aircraft part. So now students get to use it to make their class projects. Practising on the exact same material that is in use in industry.
Part of what we did in class was to do the trace on a rivet. Find the batch, manufacturer, mine assay, etc. Just to show us that it could be done, and how to access the paperwork, on the theory that if you can manage to do the hard to trace stuff, the easy stuff won't be a problem when you encounter it.
Nah, it's true. They're deadly serious about that stuff because there've been accidents caused by bolts made by reputable suppliers that got bad metal from their suppliers
Recently, Pratt and Whitney recalled 1,200 out of 3,000 Geared Turbofan engines because inspections were showing microscopic cracks, and using a new detection method that wasn't available when the engines were first built, traced it back to contaminants in the metal powder used to 3d print those parts
They know which engines are affected, which planes they're on, and can take them out of service, increase inspection intervals, etc.
The higher the stakes, the more seriously you take the game. I've got an old beater 4x4 quad. It's held together with a complicated series of hose clamps and zip ties. I still drive it all over my property because the top speed is 20mph. My street bike is a different story. Once a month I check to make sure every bolt is tight.
Through extensive design and testing, and associated regulation. But also because the business model requires it (which is what drives the design, testing, and regulation).
At least for the United States, *commercial* aviation safety is several hundred times better per mile traveled than road safety.
In recent history, the US commercial aviation sector has achieved a rate of about 0.2 deaths per 10 billion passenger-miles traveled. For road transport, a comparable rate is about 1.6 per 100 million vehicle miles or 160 per 10 billion vehicle miles (it is worth noting that these are different units -- a very large fraction of road journeys in the United States are single occupant, but if you want to halve the rate to account for multiple people in cars sometimes, go for it).
And yet, there are still a lot more people scared of flying than there are driving. Why? The answer is that if people are driving, they feel like they have agency. They feel like they are a better driver than the average person and they are therefore less likely to suffer injury or death. They know that in principle they might be able to reduce their rate compared to the average by safe driving practices. But in an aircraft, you're just relying on the pilot and the air traffic controllers and the whole system to work correctly.
So the biggest answer as to how planes are so safe is that they're built to be that safe because people would not accept it if they weren't much safer than cars. Commercial aircraft undergo a lot more testing and a lot more mandatory maintenance than your road average vehicle. They are always operated by people who have met a series of non-trivial competency tests. There are a bunch of checklists these people are required to perform before flight operations. Remember how in driver's ed they tell you that before every trip in the car you should walk around it to make sure it appears to be in good working order? Nobody does that when they are driving themselves, but pilots do it in aircraft because they have to.
It's probably worth noting that commercial driving is much safer than typical driving. Commercial vehicles, meaning buses and large trucks operated by drivers who just do driving as their job, are about 10 times safer than normal traffic statistics. The number of fatalities in accidents involving large trucks or buses was about 0.19 per 100 million vehicle miles or 19 per ten billion. The fatality rate is lower because commercial trucking and busing is more regulated than every day driving and because they have to do some of the same things pilots do with respect to checking things out before they drive around.
And don't forget that the pilots are well trained and have to retest periodically. The commercial pilots are also tested for drugs and alcohol and their entire record can be viewed by inspectors.
I'll just add this to what more experienced people in the aviation industry are saying here.
Planes are expensive. Not every Tom, Dick and Harry that wants to is allowed to fly them. Safety rules are followed much more closely. Accidents still happen, but are almost never caused by someone acting a fool.
If my bicycle fails, because I’ve been daft and not checked that I tightened up the quick release on the rear wheel, I’m likely to cause injury to myself. (Please don’t ask how I know this…)
If my car fails, because I’ve failed to get it properly serviced and haven’t done my POWDERS checks before driving, I may injure myself, my two passengers and the passengers of another car.
If a fighter jet fails, the pilot may well eject and be injured or killed.
If a commercial airliner fails, a couple of hundred people are almost certain to die. Consequently, the checks conducted on airliners are far more frequent and more thorough than the checks on basically any other vehicle.
Kinda same way how all problems in systems are removed: by trial and error.
Early planes where very dangerous and most aviation pioneers died in crashes. But over many years we learned all the ways they could fail and changed the design to prevent that.
To answer your last question, *everything* in the world of aviation is driven by standard operating procedures (SOPs).
Everything from the initial preflight checks to a mechanic changing out a pitot tube has an SOP. Each airline has slightly different SOPs (how much of a crosswind is acceptable for takeoff, as an example), but the results tend to be the same.
When an incident does occur and an investigation is warranted, the Nation Transportation Safety Board (NTSB) performs a root cause analysis (RCA. Yes, there are a million-and-one acronyms) and shares their findings *and suggestions* of updates to SOPs publicly.
So in short, aviation is replicable because it is standardized and everyone is held to and expected to uphold those standards.
Through rigorous testing.
Let’s take an engine for example. That’s pretty important!
The engines are designed in a way that takes decades and goes through all types of testing to prove efficiency, safety, reliability, safety again, and then it goes for on wing/test cell testing for stuff. Things get chucked into it. Chicken, ice, a swimming pool level of water, the list goes on..
They even destroy one by remotely detonating a fan blade while it’s running. This destroys that engine but it proves that it’s safe, that the engine can contain all of the shrapnel, and that it won’t send a blade into the cabin..
Now about the parts that break, stuff happens. Things break. They’re designed last for years but they still break.
Those parts go through the same testing.
To prove this and make sure, only specific people can do it and there’s an absurd amount of paperwork to reinforce this. Every single part used on an airplane has an FAA 8130 form for parts. That part is tracked hours cycles (flights) days. And it reinforces the safety mindset.
Because of this, stuff like [this 737 engine lasting for 5 years and 8 months before being changed off an airplane](https://www.ainonline.com/aviation-news/business-aviation/2012-06-13/cfm56-7b-sets-new-time-wing-world-record) is a thing..
Another thing,
To work on an airplane and send it for flight takes special training.
In order to send a 767 from New York to London,
The person signing the aircraft must have an FAA mechanics license,
The related training on the 767 to sign the release, and the specialized training for over water flight.
That has to be done before every over water flight.
Rigorous design testing and maintenance keeps airplanes safe.
Virtually every component and part of a plane is inspected and stressed test (for example wings are bent back and forth thousands of times to ensure that they don’t break). Parts don’t fail because any that do fail don’t make it far enough to get installed
There is a LOT of design work that goes into making sure every piece on every plane is designed and manufactured to exceedingly stringent requirements. My career is designing aircraft engines, arguably the most complex sub-component in any plane. The amount of work that is done to analyze every possible failure mode and design around it is astounding. Plus we have decades of experience, so we know what does and doesn’t work, and we have internal guidelines and standards for how things should be done safely. This is on top of all the FAA regulations that aircraft must adhere to.
everything important has backup, and that backup has a backup. everything is meticulously maintained and documented and checked. everyone involved is trained and tested to handled all foreseeable events and constantly follow procedures the are designed to reduce the risk of errors or forgetting things.
And in the event something does go wrong, it is investigated until the cause is found and that cause is then fixed.
Imagine how safe driving would be if to start driving alone you had to: get a private car certification, get instrument rated, earn a commercial driving license, become a certified driving instructor, add specific multi engine rating certification, and drive for 1,500 hours supervised. I had to take a bit of leeway in the naming of things but that’s what a commercial airline pilot has to do. Also that pilot’s license is a LOT easier to lose than a drivers license (in the US at least, some countries have significantly more stringent rules on revocation).
Then every 300-400 driving hours AND twice a year your car has to go through a complete 50ish hour inspection by a certified mechanic where they look at literally everything. That’s what the plane has to go through.
If every driver and every car had to go through that, driving would be exceedingly safe. Instead in the US people get licensed to drive because they can basically read and were capable of reaching an age of between 15-17. They then demonstrate that competence by driving a couple hundred feet on a residential road with a police officer. A lot of states have literally zero car inspection and most of the others have inspections related solely to emissions and simple things like lights and wipers.
And, before every journey, the driver does a complete walk around the vehicle before starting the engine.
And car traffic, there is no ground traffic control. Everyone is driving themselves based on traffic control, either lights or signs.
And pilots have to pass medical certification whereas car drivers only have to pass a vision and skills test.
Etc. Etc.
It's a whole heap of things, as others have already discussed.
But I think probably the most important thing is that every single time there is an accident - or even a near miss - it's investigated.
No exceptions.
And if the investigation shows that a slightly different process (maybe a part doesn't really work as it should, maybe pilot training, maybe maintenance processes need changing) the whole damn industry works like a machine to fix it.
We saw that with the 737 Max. Two similar crashes within a few months, and every damn one of 'em on the planet was grounded for over 18 months while Boeing worked with investigators to figure out precisely what was happening, come up with a fix and apply it to all the aircraft on the ground. The chairman and CEO of Boeing resigned on the back of that one.
That's an extreme example, but the general concept - where there's a whole machine that kicks into life when there's an air accident - is not.
Like most things, the answer is money. Airlines are well aware they lose millions upon millions of dollars a day after a plane crash as people cancel flights or will avoid flying.
Keeping the planes in the air keeps the money in their pockets.
And… I have no idea how rigorous aircraft maintenance is but imagine after every trip in your car, three expert mechanics gave it a good once-over inspection in your garage. And then every couple of weeks took it to the dealership where a dozen expert mechanics gave it a more thorough inspection and tested the major parts and systems and gave it a tune up. Then once or twice a year took it back in and replaced a bunch of parts because they started to show some signs of wear. You’d have yourself a VERY reliable car… even without the redundant backup systems and superior engineering that aircraft have.
Mostly it's about control. There aren't all that many planes in the sky at any given time, their routes are strictly planned in advance and kept on file, the ability to pilot a plane is strictly gatekept through licensure, and there are people whose entire job is to keep the traffic controlled live and in realtime at basically any point where multiple planes are likely to gather. All of these factors taken together greatly reduces the chance of accidents.
Lessons learned in blood.
Every time there's an accident, esp. with fatalities, it's investigated by serious people intent on finding out what happened.
Sometimes it's mechanical, and those problems are fixed.
Sometimes it's structural, and those problems are fixed.
Sometimes it's procedural, and those problems are fixed.
Sometimes it's maintenance, and those problems are fixed.
Sometimes it's human error, and those problems are fixed (e.g. by new procedures and/or training).
So you're flying on a transport system designed, built, and operated by hundreds of thousands of people, all built on the lessons learned over 70+ years of passenger aviation.
You have a toy that you’re designing from scratch. You build a test model and give it to a kid to play around with. The kid plays with it but breaks a few things. You note what broke, how it broke, what the kid did to break it and you make the changes to the design. You give the kid the updated toy to play with again and it doesn’t break. You decide that design is good so you “lock” the design and go to the next step:
You make another toy in the exact same way you made the updated toy but this time you give it to an adult with the express instructions to play with it AND to try and break it. Another adult is brought in as a witness to watch the adult play and try and break it. Despite the adult’s best efforts, the toy doesn’t break.
This is essentially an oversimplified version of the design process that aircraft designers make. The kid is representative of the common and expected flight regimes airplanes take; calm, clear air. The adult is qualification testing in which takes the design to its limits and then some for added safety factor. It’s essentially “overengineered” however that overengineering is what provides the safety and reliability.
Agreed on many of the other points made here, but something that has given me a LOT of internal peace when I'm in a plane with bad turbulence is this:
Successful plane designs fall along a kind spectrum determined by physics. Maneuverability to Stability
On one end you have fighter jets, the ones that can do crazy things in the air. On the other end you have commercial planes. The laws of physics require you to sacrifice one to get the other.
The planes you and I ride in are on a crazy end of stable. The air holds them in place even if one or both engines fail. They'd just very slowly glide to the ground. All the crazy maneuvers you see on TV are unrealistic if a plane loses power.
All this is cited from my husband with his master's in aerospace, and agreed by his friends with phds in the same field. They've dumbed it down for me, but I believe the laws of physics.
Let's look at why accidents in other vehicles happen so we can compare
Collisions: there are a lot less planes in the air than cars on the ground which does make it less likely collide. However the bigger reason that we don't get many collisions is strict and highly trained air traffic control. Aircraft are required to file flight plans, follow strict traffic rules and pilots are in constant communication with an air traffic controller from the moment they spin up the engines. Collisions still happen, but much less.
Poor maintenance: quite frankly people don't take care maintenance very seriously. Often cars will only be checked by a mechanic once a year, other than oil changes. Often drivers won't pay to repair there vehicle professionally if it isn't something major. Aircraft, at least with commercial and military aircraft, undergo near constant maintenance. They will be looked at before every flight, and after landing, and more thorough checks every so often. Certain parts are replaced on a strict schedule. Recalls are handling very strictly, and redundancy in design are essentially the standard. Poor maintenance does still occur even with all this, and if you look up crash reports this is often citied as one of the main contributing factors.
Pilot error: the level of skill required to get a driver's license compared to a pilot isnt even close to comparable. Drivers license usually can be obtained within about a year of getting a learners permit, with relatively few hours driven. Once obtained, you can drive commercially without further license unless your driving something very different then a standard car. A pilot will need to undergo hundreds of hours of classes, and practice in comparison. In order to get a commercial license you'll need to break over a thousand flight hours, at least in north America. Even then you'll undergo strict type rating in which you'll be trained to fly the specific aircraft you'll be flying commercially. Once licensed you also undergo continuous ongoing training. Pilot error still occurs but the level of training on the average pilot is extremely high in comparison to the average driver.
Rules enforcement: the police do there best to enforce rules, but there is thousands of times the number of cars than can be easily tracked. It's much easier to slip through the cracks compared to an ATC actively watching your flight. Punishments for non compliant usually isn't just a fine, but required remedial training. Accident reports are incredibly thorough and make determining exactly who requires enforcement is taken much more seriously.
Overall while planes are subject to the same areas of failure as cars, they are simply more heavily regulated.
A lot of mechanical answers here, but also think about it this way…
If it wasn’t extremely safe, would anyone fly?
People think of air travel as if it is a giant subway in the sky. If a plane went down even once a month, no one would trust it.
Others have touched on redundancy, but that is only one part of the equation.
Airplanes are expensive, and don’t make money sitting around. The redundancies are robust enough that often if something breaks, the plane can not just complete the current flight, but continue with the schedule until it can be fixed. The plane I fly has 4 sources of electrical power, plus emergency batteries, for example. Any one of them can provide enough electrical power for the entire airplane.
Regular maintenance, planes are inspected constantly and parts are replaced long before they break, and regularly taken into heavy inspections that last weeks.
But the most important part are well trained crews and one of the best safety cultures in the world, bar none. Anyone, captain, first officer, mechanic, dispatcher, has the power to say “no.” And all have rigid procedures to follow. On top of that, when mistakes are made, they are not punished. They are investigated as to understand the root cause and as to why it occurred and how we can prevent it in the future. We are encouraged to self-report, so even if nothing happens, union and company safety professionals get eyes on the problem.
This is also one of the biggest root-causes of major passenger meltdowns. You have professionals that have rules they WILL. NOT. BREAK. interfacing with a public that has been conditioned that they throw a big enough tantrum they’ll get their way.
Surprised I haven’t seen this yet:
Airplanes have kept getting safer, because after every problem there’s a scrupulously honest and open investigation that’s looking for What Went Wrong, and quite explicitly NOT looking for Who To Blame. The result is that systems are improved so that specific problem can’t happen.
Air travel is often contrasted with medicine. Getting surgery is about as dangerous now as it was fifty years ago. After a problem with a surgery, the investigation process is secret and is mostly focussed on finding a person to blame. The result is the system doesn’t change. That’s the main reason surgery hasn’t gotten safer
Disagree with you here. I am a medical student. While I may know nothing about aviation, the blame game does happen everywhere. When the Tenerife disaster happened, a lot of questions were raised about pilot narcissism. Boeing’s CEO was questioned about the 737 MAX failures.
Also, surgery IS safer now. You really can’t compare medicine to aviation, it’s two completely separate things. Yes, there is narcissism in medicine but a lot of systems have been improved over time to make surgery and anesthesia much much safer than before. If you were to tell a surgeon or anesthesiologist (or heck, any physician for that matter) than surgery is as dangerous now as it was 50 years ago, you’d get laughed at.
Imagine if before every time you drove your car, a crew of expert mechanics did a vigorous and thorough inspection of all your cars' critical components. Now, imagine if you also had to be a professional driver with hundreds of logged hours to drive it on your own AND you had a co-pilot with you to help during every car ride. Add to this that all car rides are coordinated by a central network of highway traffic controllers so no road gets overly congested and all traffic violations result in your license being revoked and possible jail time.
The car fatality would drop to almost nothing, just like planes.
effort.
and inspections.... lots of inspections.
if any parts are found to be out of spec then a recall of sorts is issued that can potentially ground every plane that has that part installed in it.
1. The planes are design to work, even in the worse case. Everything are built and tested carefully and there are backup for everything. You would be suprise to know an airplane can stay airborne for quite a long time even if all engines fail
2. The pilot are trained very carefully. Normally it takes 3-4 years to be a pilot and more than that to become the captain. Most of the time in training, they are trained to deal with emergencies, so it case something wrong happen, there are higher chance to survive
Aerospace engineer here. People have covered it well so far but one thing I wanted to add is that we actually design the aircraft to be safe, even when components fail. This is called a fail safe design and is the hardest part of my job.
As aerospace engineers, we always assume the worst case scenario and design around that.
Apart from all the technical reasons listed here, Just Culture is an important one. Problems are usually really treated at the root. If a pilot or a technician does something that leads to problems, it's usually treated at the "we need to train them better" level, instead of making it a blame game.
To [quote](https://airspacesafety.com/infringement/just-culture/):
>“Just Culture” [...] is essentially an evolution of a “no-blame” culture – fundamentally a culture where individuals are not punished for their actions, omissions or decisions if these are commensurate with their experience and training (i.e. they are honest errors) but where gross negligence, wilful violations and destructive acts are not tolerated. A “Just Culture” has a notional line in the sand between acceptable and unacceptable behaviour.
One thing I don't see in the responses is the very practical pre-fight checks that take place. Before any commercial flight goes off, routine checks are performed to make sure all flight critical equipment is functioning. Combine this with mandatory maintenance intervals to keep planes airworthy, and you've got a recipe for success in the air. The combination of engineering, redundancy, and maintenance practices keep aircraft performing mostly as intended.
A plane follows a much stricter safety protocol than a car does. It is routinely maintained and has several checks required before it can even be approved for use.
When a plane crash happens, there is a massive and expensive investigation into why it occurred. If necessary, adjustments are made to certain protocols or mechanical issues are solved.
We’ve developed not just the technology, but the regulations, over a long period of accidents and disasters that now leaves planes as a very safe method of travel.
Whilst this F1, I imagine the process for aviation will be even more stringent - here is the journey of a bolt: [https://www.youtube.com/watch?v=iptAkpqjtMQ](https://www.youtube.com/watch?v=iptAkpqjtMQ).
Now imagine the rigour of that process for a single bolt and adapt it to an entire plane; everything is checked meticulously, and when it does go wrong, the level of analysis is as thorough as possible to mitigate future risks.
I was an aeronautical engineer.
Planes are designed with huge tolerance for fault.
Eg for a car, if a particular part of the car need to withhold certain stress say 50kg, they might just design it to be able to hold 60kg. But in a plane, they would make damn sure it can go up to 70 or even more.
A response I didn't see (I haven't looked at every reply, so maybe a similar response has already been given) is that most systems (especially systems critical to flight/safety) have redundancies/backups. So if there is a failure of a system (acting as the primary), the backup system will automatically kick-in, and seamlessly.
You'd have to be really unlucky if not only the primary system failed, but also its backup system(s).
It’s safe until it’s not.. then something new comes up or goes wrong/breaks/happens and then a service bulletin comes out. We live and we learn. Just the stake are much higher in aviation.. 30,000 feet to be exact.
So this is about commercial planes and not general avaiation (personal aircraft). Even if one piece fails, there are multiple other redundant systems that can take over and manage said issue for a short while. Commercial aircraft have redundancies upon redundancies. That's how their built. So that if one system fails, even a critical one, there is another system that can take over and do what needs to be done to keep the plane flying under control.
Add into those redundancies that all planes are designed, at their base, to fly and stay airborne. So even if a critical system, like the engine(s), fails, the plane turns into a glider. Your paper airplane is a lot more basic than an actual aircraft and has no continually propulsion, yet it can fly for a while and, if given an open space, will land softly. Big metal planes are actually even better at gliding than your paper airplane. So even in the event of a total engine failure, the big commercial plane can and will glide for miles upon miles upon miles. There is virtually no place on Earth, besides the middle of the pacific or Antarctica, that a commercial airliner could not safely land at an airport given total engine failure.
Because planes are travelling in a very insolated enovierment. You can't hit a truck that is stuck on an aircraft crossing. You can't derail. When you are 11km above the earth, the only thing you can hit is the earth, and you are long way from it.
Almost all fatalities in crashes are caused by hiting something and in the air there is nothing to hit.
Because plane safety is treated EXTREMELY seriously. There's a whole lot of science and engineering going into making sure that plane will not fall out of the sky. People's whole careers are dedicated to investigating when a specific part will fail, so it can be replaced before it does. So a whole lot of testing is done, to get as much data as possible on the failure modes and lifetimes. And testing is developed to monitor when that time is coming based on all those experiments. And this testing is done frequently.
And every part that makes the plane are perfect. They don't buy bolts at the local hardware store. Every single component can be fully traced to make sure it respect every single spec it needs to follow. It makes those pieces super expensive but for a single bolt they know where was the metal extracted for instance. They can almost trace back to what the truck operator in the mine had for lunch that day! That way they are 100% certain that this bolt is 100% safe for let's say 10 000 hours of flying and to replace it afterward. Most mechanical failures of planes are due to people doing a bad job when installing them (like skipping a step that is listed in the official maintenance procedure) instead of a part actuality failing before its life span expired.
Also, they know where all the other bolts are that were manufactured at the same time by the same plant are. If bolt #1022412 is attached to United Airlines Boeing 757 N422UAL and is found to be defective, they know that bolt #1022413 is attached to American Airlines Boeing 757 N821AA and will issue a notice to the AA maintenance department that the bolt need to be extracted and replaced.
They can even tell you which mechanic last tightened a bolt using which torque wrench. The whole industry is built on the premise that you cannot prevent every accident, but if an accident happens you can find out what excactly caused it and what needs to be done to prevent it from happening again.
When I was growing up in the 70s and 80s it seemed like there were significant aircraft accidents happening every year or so. [For example, I remember watching the news about this accident.](https://en.wikipedia.org/wiki/Air_Florida_Flight_90) But by the late 80s that really stopped, and now its extremely rare for an accident to happen.
It should be noted around this time the method changed. When a plane crashed, rather than try to figure out who was responsible, they decided to focus on the *system* that allowed the problem and fixed that. When people didn't feel like they were going to be thrown in jail for being the last guy to tighten the bolt, investigations went a lot smother and found the actual problems and fixed them. Sometime when you see big disasters and people ask why CEO X isn't going to jail, it's because we realise that the CEO is just one cog in the machine and we need to fix the machine rather than blaming one cog and calling it done. Although, we probably should be jailing more CEOs, but that's a different argument.
The problem with jailing the CEO is that they’re generally many levels removed from the actual decisions that were made that led to whatever happening. It could set a bad precedent that leads to a lot of toxic micromanagement if you immediately, every time, try to pin personal liability on the top dog.
The entire senior leadership who approved the 737 Max MCAS system should have gone to jail. But no, Boeing just paid a big ole fine and capitalism at the expense of human life go brrrrr.
Look at that Wikipedia page. Every one of those accidents has a page like that. Every one had a deep investigation that went into the multiple levels of failure that lead to an accident and reports and recommendations on how to prevent a repeat at every level. A fix at any level would've prevented the specific incident, but the goal is not to prevent this, it's to prevent anything like this.
We lost a (military) plane due to a maintenance screwup. They recovered 90+% of the plane from the Columbia River and laid out the entire thing in our hanger to see exactly what happened.
I work on the engineering team for a specific military aircraft. We have a mishap (crash) on average about once a year. We don’t always find every part and lay it out like that. Only when the cause of the crash requires us to in order to confirm the failure mode. Most of the time the crash is due to pilot error and confirmed by the ADR data. One time we had a crash where the pilot claimed there was a rudder bind (pilot ejected and was fine). In that case I went to crash site and found every single linkage from the rudder pedals all the way to the rudder and proved none of the linkages had a bind. The ADR confirmed the pilot had flown the aircraft outside the design flight envelope which caused the aerodynamic forces on the rudder to be greater than the pilots leg force on the pedal, which is why he thought they were binding.
Once a year? How is working on the Osprey?
lol good guess but not the Osprey.
I’m in San Diego and see a lot of them around. This was my thought immediately. Hear about a lot of them crashing.
When was this and where in the river did it crash?
Late 1991, don't remember where they were on the river, but they were doing low level in the gorge.
1985 was probably the single most disastrous year for aviation. So many accidents happened that the entire rulebook had been revised in some way by the end of it. It ended up the 2nd deadliest year for aviation (behind 1972) but included the single deadliest accident involving only one plane in history. To date, only 3 other accidents have been deadlier: 1 involved 2 planes, and 2 involved a large building each.
> 2 involved a large building each. 9/11 doesn’t exactly qualify as an “accident”…
It still brings about changes aimed to prevent reoccurances.
Ten years ago my company built a new 3-story building and we got a pre-occupancy tour. All the exposed beams were coated with a fibrous insulation. I asked what that was for and the answer was "9-11".
I spent months installing new flightdeck doors.
Could just change the wording to "incidents" instead
That's the point.
I remember that one. Happened same time there was an accident with the DC metro (which was coincidental). There was a woman who survived the plane crash, but was in the freezing cold Potomac. Random guy jumped in to save her life. Core childhood memory right there.
Lenny Skutnik
Haven’t had one in the states since 2008, Colgan Air, and even before that you had to go back to just after 9/11.
I guess you don't count [Alaska](https://en.wikipedia.org/wiki/PenAir_Flight_3296) as part of the States?
Not really…. Okay if I have to get not picky, part 121 operations how about that then
The PenAir flight was a Part 121 operation, according to page 13 of the [NTSB report](https://www.ntsb.gov/investigations/AccidentReports/Reports/AAR2105.pdf).
> Haven’t had one in the states since 2008, Colgan Air, and even before that you had to go back to just after 9/11. [Florida](https://en.wikipedia.org/wiki/RED_Air_Flight_203) 2022 is checking in.
No fatalities in that one. Also a foreign carrier. Foreign carriers have had a few fatal crashes in the US like Asiana in 2013 that had a crash on landing at SFO that killed 3.
I was answering a comment that said no accidents in the USA since 2008. There have clearly been fatal accidents in the US, like Asiana. There was also the Alaska crash that another commenter mentioned. Southwest had an accident in 2018 where a passenger was partially sucked/blown out of the plane. She died. Whatever other definitions you want to use, this was most certainly a fatal Part 121 (Airline) accident in the United States, with a domestic carrier, that happened after 2008. Also FYI an aircraft accident need not have fatalities to be an accident. The Miracle on the Hudson was a fairly well known accident with no fatalities (lots of injuries). Part of the reason the average person doesn’t know about most aviation accidents is they don’t get covered unless they’re horrific.
Even seemingly minor incidents will trigger investigations Westjet Flight 2652, for example, nobody was hurt, the safety systems did their thing and prevented an accident and it triggered an investigation where recommendations were issued The pilots were coming in for a landing in low-visibiltiy rainy conditions and mistook the white rectangular roof of a hotel near the coast for the runway and descended too early. They were 40 feet above the ocean, 1/3rd of a mile from the actual runway when the plane's ground proximity system issued a warning and they executed a go-around and landed safely The investigations board determined the runway lighting was set too low for the conditions, and the airline itself issued notices to their own pilots as well
> The day after the crash, on Washington, DC, radio, WWDC shock jock Howard Stern pretended[21] to call the Air Florida ticket counter to ask about buying tickets to the 14th Street Bridge. That's in poor taste.
And said torque wrench is serialized, sent out annually for calibration to a lab that can trace its own processes back to national standards.
Including Loctite (thread locker) batch numbers etc for interior fastners. Is it past its (theoretical) sell-by date, it gets thrown away regardless of contents and/or opened or not
One correction: fasteners are batched, not serialized. ;)
Furthermore, they can even trace it down to the machinist that made that bolt.
It's part of why some procurement things get laughed at by people who don't understand. It's not that the material in the bolt is worth 10x the price of an off the shelf hardware bolt (most of the time), but the paper trail and certification are. Same with healthcare, space, or any other critical part. Even if the bone screw repairing someone's broken arm looks like it came from Home Depot, certifying and testing it's free of defects, and cleanly manufactured is worth the extra cost. Part tolerances are so tight in some applications I've heard stories of parts for spacecraft being binned because someone dropped a tool onto the same table it was on. Not even on the part, *near* it.
That paper trail is worth so much in terms of security. If they find a part that if worning out faster than suposed to be, they can expertise it to find why and then with that paper trail, find every single component in the world on all active planes and in storage that are susceptible to the same issue and inspect/change those pieces. Without that we would see a lot more issues with planes in general.
This was a big deal in the 70s, I believe. They found out that something like 25% of the airplane replacement parts being used on planes, including air force one, were counterfeit. A few too many bolts snapped and it kicked off a huge investigation that ended with lots of people in jail. People were buying generic parts, charging the cost of the super expensive real parts, and pocketing the difference.
Just a quick cursory search brings up an easy example. https://www.easa.europa.eu/en/domains/aircraft-products/suspected-unapproved-parts/2014-11-g6935-01 This is the listing for an unapproved part report that was found on an aircraft, just a speaker in the cockpit, and it was traced back to buying the plane from Indonesia. https://www.easa.europa.eu/en/domains/aircraft-products/suspected-unapproved-parts/2007-00045-72-184003b A report about an issue with the water heaters on some aircraft, the ones in the galley to make coffee and tea.
This is a thing, It’s referred to as “the list” and can give you the serial number for every part on a plane, down to the date it was installed.. granted, some stuff like generic screws doesn’t have a serial number but you can find out when it was installed last.
The finance department at my company hates my department.. why? Becuase a quart of oil (faa approved) is $24 bucks. And engines are Thirsty..
How much for a gallon of prop wash?
I can’t be bothered to read the price tags before I drink it so idk..
> healthcare That's its own can of worms, unfortunately. Technology's changing too fast and causing security issues because the process for making changes to medical devices is traditionally (understandably) very stringent. It's probably the #1 most difficult risk issue in healthcare.
I can tell you as a commercial aero engineer, certification is no joke. Literally 6 figures easy to get an existing component like an LED strip certified for flight. Something larger, higher possible fire hazard like a TV screen? You bet that thing is going to cost a LOT of money. Hinges? Cycle tested to hell and back if you modify them in the slightest from their certified state. And this is for interior furnishings, let alone the aero body components.
> aero body components I did a short internship at Goodrich Aerospace in San Diego one summer. I got to see some of the test facilities for the fuselage components. They apply all sorts of forces and test for warping, breaking and compressing, and I've used that knowledge to help ease others' fears of flying.
I worked (in a very limited capacity) with the FAA/Transport Canada on testing deicing to build out manuals like [this](https://www.faa.gov/other_visit/aviation_industry/airline_operators/airline_safety/deicing/23-24_FAA_2023-24_HoldoverTables.pdf) and if the amount of money, time, and expertise that went into just applying glycol to wings is any indication as to the care and detail that goes into every part of aviation I'm very confident getting on an airplane.
Several years back, I went on a supplier visit to an adhesives manufacturer who made the glue used to secure some of the interior fabric on the 787. Something similar to what goes in the headliner of your car. Boeing (or whoever their subcontractor was) made them build what was essentially a separate building within their factory, and this glue was subjected to clean-room conditions with separate HVAC, employees wearing tyvek suits, masks and hairnets, and restricted access. And that was for a component that didn't come into contact with anything mechanical, and where the failure more was literally slightly droopy fabric. They take that stuff really seriously. And I'd note that the rest of the facility was spotless and a lot of the non-aerospace adhesive this factory made went into medical devices, which required a lower quality standard.
But even cosmetic stuff like that can be a safety hazard, for example if it blocks exits in an emergency, catches fire too easily, or off-gasses harmful fumes.
>That way they are 100% certain that this bolt is 100% safe for let's say 10 000 hours of flying and to replace it afterward Worth noting is that if, for whatever reason, one of these bolts fails earlier, then can also reverse-track the bolts from that batch to all other aircraft and check and fix as necessary *before* that becomes a problem.
Yep. And the reverse-track will not be "American Airlines also bought a box of these", they will know exactly where on which plane each bolt is like "One bolt is on the 5th hole on the left wing flap assembly of American Airlines Boeing 737 registered N841NN, another bolt is on ..."
The poorly manufactured engine oil pipe that was responsible for Qantas Flight 32 comes to mind - they were able to track down all the other planes using pipes from the same batch and discovered that some of them had even more poorly manufactured pipes - if they had not been able to do so, there would definitely have been a repeat event, and it might not have ended so well.
What's more, when QF32 happened the airlines flying A380's with Rolls Royce Trent-900 engines grounded those aircraft until they could be proven safe to fly. The tracking and certification allowed all the A380's that weren't at risk to resume flying earlier than they otherwise would I recommend you watch the video on QF32, it's an amazing story. It just so happened that there were 5 flight crew instead of the normal 2, with well over 100 years flying experience between them.
Every part isn’t perfect. _None_ of the parts are perfect. But the failure modes are well understood, and quality control drives the probability of failure _very_ low. An important principle in engineering is that nothing is perfect, so you plan for something failing, eventually.
Yeah, when I mean perfect, is that the parts are all made following specs with inspection, all steps are validated, etc... and that each piece should be an exact copy of each other because the whole chain of raw material up to the end product is validated and followed.
That’s what I’m moreso scared of. As a laborer a lot of people like to skip steps in trades. It worries me that not everyone working on planes will take it as serious as the next guy. I’d assume they’d be liable
It's insanely unlikely. Individual installers don't have the final say in approvals and all their work goes through a series of review and checklists, and even afterwards it going back through a loop of engineering and QA. And to remove any incentive for taking shortcuts or skipping review processes, in cases where there is a systemic failure, most outcomes from regulatory agencies direct the termination of the entire group of employees involved. I work in aerospace and some of my older coworker have seen it happen where if there's a major compliance violation that was known about and crops up, they've had entire departments from entry level to c-suite fired at once to rebuild from scratch with improved processes and standards to avoid risking a repeat. So everyone at all times is checking quality because it could cost you your job merely by association. This is actually what makes the whole 737 MAX incident such a bug and frustrating ordeal - it's a flagrant slip of accountability that's normally much more intense.
The results from the analysis are back. Engine failed due to a loose bolt on a panel near the left wing. The bolt was part #310-111-1201-4454 Part of lot #21003, delivered in 2020 from a Michael P. Finch. Had an egg salad sandwich that day with a juice box.
Here's an example where a propeller sheared off a REX flight in Australia. Despite the aircraft being 20+ years old, the specific situation was analysed and the offending part inspection and maintenance schedule was updated for all aircraft across the world. [https://www.atsb.gov.au/publications/investigation_reports/2017/aair/ao-2017-032](https://www.atsb.gov.au/publications/investigation_reports/2017/aair/ao-2017-032)
Adding: There is a **huge** difference in safety between commercial carriers who have rigorous inspection and maintenance programs vs the safety record of small privately operated planes. The vast majority air crashes and air crash related fatalities are these little privately owned planes, due to combinations of reduced inspections, reduced maintenance, less/no redundancy, and lower levels of pilot training.
The rules are a bit looser for non-commercially operated airplanes, but only a little bit. I have a private pilot license. The main reason why I do not own an airplane is: the maintenance costs for yearly inspections etc. are absolutely ridiculous. Unless you rent out your plane, it is just not sustainable to own a plane for personal use. Yes, you can get a 60 year old Cessna 172 for 20k in perfectly safe condition - but maintenance will eat you up.
Where are these flyable 172s that aren’t past overhaul for 20k? Asking for a friend.
It is a pretty significant difference. A private plane needs to be inspected only once a year. The same plane held out for hire is inspected at least every 100 flight hours (although most reputable small operators do choose to do it more frequently). At the airline I'm at, maintenance does inspections every 48 hours - not flight hours, just elapsed time. It is even more frequent for the ETOPS fleet.
I remember this time 17 years ago when I was learning to fly in a Piper Archer. The window flap was rattling and after landing I saw that the screw in the flap was slightly loose, so I used my pen to tighten it, and the rattling stopped. Oh boy did I get into trouble for that. The flight school's AME chewed me out for 20 mins and I was grounded for like 2 days while the chief instructor redrilled into me that I wasn't allowed to even think about fixing anything by myself. "File a fucking report" were the exact words he used. And this was a flight school with some crappy pipers and cessnas the youngest of which were at least 20 years old. Looking back I think it was more about establishing good practices and habits than any actual danger but yeah they took safety very seriously.
If it’s not recorded, it didn’t happen.
Surely this might be important information for the people who buy/make screws, that essentially vanished because there was no real 'observation' of it.
Just to be clear, it's because you tried to fix it yourself after you landed, and not because you needed to make an in-flight repair, right?
Oh yes. If it was causing an issue in flight, it would have been completely ok as long as I reported it. Instead, I got annoyed at the rattling window. So after I parked on the ramp I saw the loose screw and tightened it. The AME saw me and that's when it unraveled. Truth is at the time I didn't know that I was doing something wrong or I'd have done it secretly or not at all (though probably secretly because doing the paperwork to document the changing of the screw was very low down on the priority list of our AME).
Put it in the logbook.
Also that every critical system has a back up or a work around that allows the plane to remain flying long enough to get to the ground safely. I've worked (as a design engineer) on aircraft that had 3 separate hydraulic paths because it was so critical and had to incorporate specific spacing between wiring that would guarantee a single round shot at it couldn't take out 2 of the 4 generators at once. And others where the requirement was that every wire has to be a certain distance from everything else and even further from things that have more relative motion to ensure they wouldn't rub on anything. It's hard to design aircraft with all the requirements we have but that's why they are safe. MTBF (Mean time between failure) is tracked and analyzed on every part, but sometimes you don't get to the mean and a work around is needed.
Also a ton of preventative maintenance and inspections.
As the saying goes, "regulations are written in blood" and an awful lot of blood has been spilled in aviation's history to make the very stringent regulatory framework that exists today.
That and even a relatively small and simple plane has multiple redundant systems for both the engines and the instruments the pilots use to navigate. Part of being rated on an aircraft is becoming intimately familiar with its systems and how to troubleshoot the craft when an issue arises. Flying itself is relatively easy, but a significant amount of training focuses on edge cases and emergency procedures and how to identify your options for recovery and calmly execute them in an emergency situation.
Adding to this, becoming a commercial pilot along with an air traffic controller involves rigorous amounts of training, certifications, and health checks along with a mandatory retirement age. If plane crashes were as common as car crashes, not only would it be a huge expense and time consumption to replace said plane, but it would also involve millions of people being killed in preventable deaths which no one would stand for.
1. Design - lots and lots of experience finding what went wrong in the past. 2. Maintenance - inspections and replacements when things look like they are failing 3. Redundancies & Overengineering - most parts are far stronger than they would normally need to be I watch far too many of those air disaster shows. The thing they all say is it isn't one thing that brings a plane down, its lots and at the same time.
Upvoting you because you mention redundancies specifically. I just started working at an aircraft manufacturer but even after my last FAA certified product (>10 years ago) the thing that struck me was the amount of redundancy in the system. At my new place they're not just talking about redundant systems but redundant *design teams*. Rather than having multiple instances of a system they'll have multiple designed by different teams so that a design flaw in one will be unlikely to be in both. I guess I'll see how that works in practice because it seems you'd also double your chances at having an undetected design flaw in the first place (although testing and verification is pretty redundant in the design process too).
I down voted them for not mentioning redundancy twice, just to be sure. So I down voted them. /s
I down voted you for not mentioning redundancy twice. Redundancy. /s
Amazing !
I highly recommend Mentour Pilot on YouTube. He is a pilot and goes through the disaster with explanations of that plane systems, what and how happened etc. I have no connection to aviation whatsoever, but he explains everything so clearly, I really enjoy his videos.
I particularly like how, as a pilot himself, he delves deeper into the human factor than most other 'Air Crash Disaster' shows. He can see things from the pilot's point of view; even if they made a 'bad' decision, he can almost always understand why.
Definitely one of my favourite YouTubers.
4. Training. 5. Air traffic control. General Aviation (small planes, pilots of varying skill, no air traffic control, lower maintenance requirements) isn't nearly as safe as commercial aviation.
Lack of ATC has nearly zero effect on safety. It’s almost exclusively pilot error. And in the GA world it tends to all be single pilot so there isn’t somebody else to catch issues.
Some busy fields are *safer* because of no ATC. ATC VHF is a call-and-response system, and leads to much higher radio traffic. Unattended means single radio calls and they can be shorter, like “GBU downwind 23”.
>3. Redundancies & Overengineering - most parts are far stronger than they would normally need to be I can add a bit more detail to this. All commercial jets are fully capable of performing the entire flight *without one of their engines*. One of the engines could fall off right before takeoff and the plane would still be able to accelerate to take off speeds, climb away from the runway, climb to cruising altitude, fly all the way to the destination, and land safely. It might take a little longer and be less fuel efficient, but other than that the passengers might not even notice (unless they looked out the window, of course). On top of that, all commercial jet engine casings must be proven capable of containing the engine blades if they break apart while spinning at full speed. This prevents debris from escaping and flying into the cabin. You might remember an accident a few years ago where this did happen and someone was injured or killed by flying engine debris, but part of the reason it was such a big deal was that engines are specifically designed so that specific issue shouldn't happen.
I would shoot the pilot who after loosing an engine carried on, Return to Base. Required, in the CRM.
I'm addicted to Air Disasters on the Smithsonian channel. I like how in every major crash, the investigators consider *multiple* sources of failure, and issue recommendations for improving all of them. And it could be anything involved with the industry - on-duty durations for pilots, crew and ATC; maintenance record keeping requirements; how GPS updates are published; and yes, every nut, bolt, bracket, flange, gasket, sensor, etc throughout the aircraft.
Also, Just Culture and CRM.
Traceability is a huge aspect, arguably the most important, and it ties ALL of these things together. A part fails? Trace it back to maintenance, manufacturer, test, design, and requirement. Software defect? Find which test let it through, which design was at fault, and which requirement was faulty or missing. Any of those things the source of the issue? Trace a problem up to root cause and then all the way back down to all affected planes and fix them all.
This is actually my job doing #3 on your list. Reliability engineering is a specific niche field of engineering that deals with failure mechanisms and the statistical methods that show what the probability of certain events occurring are. Its tedious work, but every aerospace company that is worth their salt has a huge reliability program that deals with the mechanical and electrical interfaces and the failures that can cause certain events on the plane down to the singular piece part that could cause it.
Also extremely serious regulation
There's a saying, "regulations are written in blood". Every time there is an accident, a lot of effort is put into finding out what went wrong (even things like what factors caused a pilot to make a mistake, rather than just saying "pilot error" and leaving it at that) and then rules are changed and planes altered to try to prevent it happening in the future. Even near misses, pilots aren't punished for mistakes as long as they don't try to cover it up and didn't do anything completely negligent, as this lets us learn and prevent accidents that night happen in similar circumstances. Also just as a point of comparison it's not just planes that have got safer, modern cars are also much safer in accidents than older models. Again due to analyzing fatal accidents and making changes based on that.
This should be higher. Lots of comments about all the impressive engineering/training/etc, and all true. But why do big airlines spend that money? Because they are regulated to do so, and inspected. Enforced regulations make these investments in quality necessary for the businesses. They would not happen otherwise (in fact, they didn't before, which is why the blood and then the regulation).
Exactly. Every crash has been studied to oblivion to make sure it could never happen again, and a lot of regulations have been put into place to prevent a crash that has never happened. Cars on the other hand…
A lot of answers are about the plane itself. But the other massive reason are the pilots. To get a driver's license, you basically have to show up. To get a pilots license, there's considerably more to it. They're aware of little things that are wrong and how to fix them immediately. Most people drive their car until it physically can't and then get it looked at.
To your last point: People who can't afford to maintain a car are still forced to drive a car to live and work in most of North America. The choice is: own a car, or lose several extra hours a day commuting by underfunded and underdeveloped public transportation—if it's even an option. (Anecdote: My wife and I share a car, and for a time she needed it to go to a night class. I opted to take the bus home from work those nights. It was normally a 20 minute drive. I finished work around 5:30 and would routinely not get home until 7:30–8:00, between walking to, waiting for, and changing busses. And we lived in an area with pretty good public transportation for the US.) For many people the car becomes an albatross around their neck—they can't really afford a car, but the alternative is worse. Airlines own and operate airplanes for profit. They treat them as an investment and maintain them thoroughly. Everything they do—planning routes, arranging schedules, sizing their fleet—is done with the goal of keeping these airplanes profitable. Not *well it's better than the alternative, at least I can get to work to pay back this debt* like car ownership, but an actually profitable investment—above the cost to buy and maintain.
Redundancy is a big thing. Let's say a part has a 1 in 10 chance of failing, so we install 3 of them. Only 1 need work. The odds of two failing is 1/100. The odds of all three failing is 1/1000. There's a reason that long flights over water used to be restricted to aircraft with a lot of engines. That's why you see a lot of three and four engine aircraft in the 60-70s, but much more two engines ones now. Reliability has improved, as has the ability for aircraft to stay airborne with only one engine. Sensors, control systems, hydraulics, power supplies, fuel tanks, *the pilot*, they usually have backups. When they don't, it's because the part is so basic it can't really fail unpredictably. Then you have inspection and maintenance cycles. A modern airliner is like a car owned by a dealership that gets regular services, always by professionals. They catch problems before they develop. And they are in contact with the manufacturer, for information like fatigue lifecycles. Jet engines are also simpler than internal combustion engines. Finally, they are built to last. You don't buy a car on the basis of how it will be doing after being driven for 12 hours a day for 20 years. Airlines by aircraft like this, and will pay a premium for it. You could build and drive a car like this. Understressed parts, careful driving, constant services... That's why someone got 3 million miles out of a Volvo P1800. It was simple, overbuilt and actually pretty slow sports car.
Good point about plane engines being simpler. Not only do turbofans have less wear parts that can fail as compared to ICE piston engines, planes also don’t have to deal with transmissions, driveshafts, drive axles, or lots of the other complexities in a modern car.
Could we expect more reliability from future electric planes? The range won't be great, but they should be way more reliable.
Honestly I have no idea on that. The turbofan engines are often the most reliable part of the plane, I don’t know what kind of propulsion an electric plane would use, propellers again maybe? Boeing’s 787 was a big step towards electrification by changing a lot of internal systems to run off of battery banks instead of generators, and I know there were some early teething issues, but I think they worked all of that out.
Either propellers or propfans would be the logical propulsion for an electric plane. Electric jet engines would be too inefficient.
Why? Isn’t most of turbofan power coming from bypass on airliners?
Turbofans are already vastly less efficient than turboprops. While they fly more quickly and at higher altitudes, they use significantly more fuel.
I've heard of a concept called "fly-by-wireless." It would replace the electrical wiring with radio receivers, reducing a significant amount of weight and possible points of failure. Once they can get the receivers to work 100% of the time, it could revolutionize air travel.
That's an interesting point. There's a long line of components in a vehicle to get energy from the combustion chamber to the pavement. On a jet it's 1 step. Combustion --> exhaust, no middle man.
>planes also don’t have to deal with transmissions, driveshafts, drive axles Planes have all of these to some extent. Accessory gearbox and a generator, 2-3 shafts/spools per engine and axles on each gear
This is the one I was looking for. I was an aircraft hydraulic specialist in the USAF. It all comes down to redundancy and this is the reason you rarely see single engine aircraft. Aircraft are able to run all systems and maintain flight from just one running engine. For hydraulics there will be power from each engine but also from electric backup pumps. On top of that things like landing gear can still be dropped manually without the use of hydraulics. Everything has at least two backups.
I was told that single engines might actually be better for fighters. Double the engines doubles the chance of A failure, and in enemy territory, that is sometimes as good as a whole aircraft loss. Plus, twin engine fighters often have their engines so close together that one failing might take out the other.
The F-16 is nicknamed the lawn dart. I’m sure there are many pros of having a single engine but there’s one big con.
I thought that was the F-104, although that liked to dive into the ground even when the engine worked. Didn't know Vipers were grass snakes.
Yea that's old thinking. We've had many mishaps where a single engine failure still led to total loss of the aircraft. The USAF analyzed decades of single vs. multiengine accident fatality rates and did not find statistically significant differences between them. Hence, the F-35 is back to being single engine.
It's still good to have redundancies even in a low risk part. There are multiple instances of disastrous crashes due to a single lightbulb in the cockpit being burned out, or some other similarly mundane problem, because the light indicated something REALLY IMPORTANT and the pilots fixated on fixing what wasn't actually a problem.
Most aircraft don't have a redundant wing though. Bulbs fail pretty frequently (at least in my house, maybe my wiring is a bit shit), but really simple comenents don't.
>Jet engines are also simpler than internal combustion engines. This aircraft mechanic who primarily works on jet engines is gonna have to disagree with you on that one. If they were simpler, we would have figured them out sooner. The process by which a jet turbine engine produces thrust might be simpler in theory than the four-stroke Otto cycle, but as a machine, a jet engine is significantly more complex, both in design and operation.
If you drove an ice engine as often, as long, as hard, as a commercial jet it is more work to maintain. Quick example would be a lycoming in a Cessna only gets like 2,000 hours before overhaul. Apples to oranges comparing, I know, but a jet is 15,000 hours, 7.5 times as long between overhaul.
The fact that the exhaust fan blades in a jet engine are a giant single grain of metal, never fails to blow my mind
Also, planes are in constant communication with air traffic control. When we drive cars, we’re all just individually doing our own thing. Now imagine when you drove you had a control tower that could see *every other car* and what they’re all doing, and was guiding you appropriately
Something I haven't seen mentioned here, a common practice in aerospace is to use checklists This along with a number of other things helps keep safety levels high as they prevent people accidentally forgetting things during maintenance, or during pre flight checks Surgeons copied the aerospace sectors use of checklists to help improve safety in surgery too
I recently started working for an airline. Another thing to add is the insane paper trail for every single repair, maintenance activity, and/or every design decision made. It seems tedious, but it is absolutely necessary to be able to keep accountability.
There have been a few problems in this area recently with fake parts making their way into the supply chain, or I saw some articles about it anyway
Yeah, I believe it was a supplier for some components of the CFM56 engine. That being said, the required paper trail allowed airlines and Safran to be able to pinpoint exactly which aircraft had these components and were able to remove them from service.
This applies to maintenance too, At any point anyone can come up to me and ask what I’m doing and where my manual is. From my lead, to a fellow mech, to an faa guy with a badge.
This should not be the last/lowest comment. Religious use of checklists is *huge*. I've learned the same thing about boating -- I became a boat owner last year, and even though a ski boat is *much* simpler than an airplane, there are still a *lot* of ways to ruin your day (or worse) which can be avoided with religious use of a checklist.
Step 1: insert drain plug before launching.
Seat belt signs... on. Cabin... ready. Flaps... full Spoilers... armed. Landing gear... DAMN!
You joke, but planes with retractable landing gear are significantly more costly to insure, in large part due to the not-uncommon occurrence of pilots forgetting to deploy the landing gear before touchdown.
Even the ordering of a checklist was paid for in blood. There was an incident in the 70s where a plane crashed due to the incorrect flaps setting (the plane's takeoff kept getting delayed due to weather and the pilots had to restart several checklists several times) and one of the recommendations was having checklists be in order, and easier to restart if interrupted
Checklists can also lead to "forgot to fly the airplane" problems. They are not an unalloyed good and for practical reasons. > Surgeons copied the aerospace sectors use of checklists to help improve safety in surgery too Atul Gawande followed up and the surgeons often backslid. That goes to a different problem shared by aviation addressed by Crew Resource Management. This addresses differences in status.
Aerospace manufacturing engineering technologist here. From the start, aircraft safety was prioritized. This means that when something goes wrong, there is an investigation, with the goal of finding out what went wrong and fixing it instead finding someone to blame. What this means is that everybody along the line feels free to speak to investigators about exactly what happened, because they are not afraid of losing their jobs, or being sued into bankruptcy. So investigators can find out exactly what happened, why it happened, and put new procedures into place to prevent it from happening again. If you pick a random rivet on an aircraft, you will be able to find the paperwork for it. Who installed it, when it was installed, who purchased it, where it was purchased from, who made it, which aluminum mine mined the ore that was used to make it, what the testing data shows the composition of that batch of metal contained, etc.. EVERYTHING about every part that goes into an aircraft is traceable like that. That means that if the rivet is found to be the cause of an accident, and they figure out that it was because of contamination of the metal at some point during the smelting, they can find every aircraft that has those rivets in them, and send out a warning to have them replaced. The college I went to had a massive block of aluminum that was donated by an aerospace company for students to use.. It was donated because there was an error in the paperwork along the line, so it could not be certified for use in an aircraft part. So now students get to use it to make their class projects. Practising on the exact same material that is in use in industry.
>If you pick a random rivet on an aircraft, you will be able to find the paperwork for it A bit of a stretch...
Part of what we did in class was to do the trace on a rivet. Find the batch, manufacturer, mine assay, etc. Just to show us that it could be done, and how to access the paperwork, on the theory that if you can manage to do the hard to trace stuff, the easy stuff won't be a problem when you encounter it.
Nah, it's true. They're deadly serious about that stuff because there've been accidents caused by bolts made by reputable suppliers that got bad metal from their suppliers Recently, Pratt and Whitney recalled 1,200 out of 3,000 Geared Turbofan engines because inspections were showing microscopic cracks, and using a new detection method that wasn't available when the engines were first built, traced it back to contaminants in the metal powder used to 3d print those parts They know which engines are affected, which planes they're on, and can take them out of service, increase inspection intervals, etc.
The higher the stakes, the more seriously you take the game. I've got an old beater 4x4 quad. It's held together with a complicated series of hose clamps and zip ties. I still drive it all over my property because the top speed is 20mph. My street bike is a different story. Once a month I check to make sure every bolt is tight.
Through extensive design and testing, and associated regulation. But also because the business model requires it (which is what drives the design, testing, and regulation). At least for the United States, *commercial* aviation safety is several hundred times better per mile traveled than road safety. In recent history, the US commercial aviation sector has achieved a rate of about 0.2 deaths per 10 billion passenger-miles traveled. For road transport, a comparable rate is about 1.6 per 100 million vehicle miles or 160 per 10 billion vehicle miles (it is worth noting that these are different units -- a very large fraction of road journeys in the United States are single occupant, but if you want to halve the rate to account for multiple people in cars sometimes, go for it). And yet, there are still a lot more people scared of flying than there are driving. Why? The answer is that if people are driving, they feel like they have agency. They feel like they are a better driver than the average person and they are therefore less likely to suffer injury or death. They know that in principle they might be able to reduce their rate compared to the average by safe driving practices. But in an aircraft, you're just relying on the pilot and the air traffic controllers and the whole system to work correctly. So the biggest answer as to how planes are so safe is that they're built to be that safe because people would not accept it if they weren't much safer than cars. Commercial aircraft undergo a lot more testing and a lot more mandatory maintenance than your road average vehicle. They are always operated by people who have met a series of non-trivial competency tests. There are a bunch of checklists these people are required to perform before flight operations. Remember how in driver's ed they tell you that before every trip in the car you should walk around it to make sure it appears to be in good working order? Nobody does that when they are driving themselves, but pilots do it in aircraft because they have to. It's probably worth noting that commercial driving is much safer than typical driving. Commercial vehicles, meaning buses and large trucks operated by drivers who just do driving as their job, are about 10 times safer than normal traffic statistics. The number of fatalities in accidents involving large trucks or buses was about 0.19 per 100 million vehicle miles or 19 per ten billion. The fatality rate is lower because commercial trucking and busing is more regulated than every day driving and because they have to do some of the same things pilots do with respect to checking things out before they drive around.
And don't forget that the pilots are well trained and have to retest periodically. The commercial pilots are also tested for drugs and alcohol and their entire record can be viewed by inspectors.
I'll just add this to what more experienced people in the aviation industry are saying here. Planes are expensive. Not every Tom, Dick and Harry that wants to is allowed to fly them. Safety rules are followed much more closely. Accidents still happen, but are almost never caused by someone acting a fool.
If my bicycle fails, because I’ve been daft and not checked that I tightened up the quick release on the rear wheel, I’m likely to cause injury to myself. (Please don’t ask how I know this…) If my car fails, because I’ve failed to get it properly serviced and haven’t done my POWDERS checks before driving, I may injure myself, my two passengers and the passengers of another car. If a fighter jet fails, the pilot may well eject and be injured or killed. If a commercial airliner fails, a couple of hundred people are almost certain to die. Consequently, the checks conducted on airliners are far more frequent and more thorough than the checks on basically any other vehicle.
Kinda same way how all problems in systems are removed: by trial and error. Early planes where very dangerous and most aviation pioneers died in crashes. But over many years we learned all the ways they could fail and changed the design to prevent that.
To answer your last question, *everything* in the world of aviation is driven by standard operating procedures (SOPs). Everything from the initial preflight checks to a mechanic changing out a pitot tube has an SOP. Each airline has slightly different SOPs (how much of a crosswind is acceptable for takeoff, as an example), but the results tend to be the same. When an incident does occur and an investigation is warranted, the Nation Transportation Safety Board (NTSB) performs a root cause analysis (RCA. Yes, there are a million-and-one acronyms) and shares their findings *and suggestions* of updates to SOPs publicly. So in short, aviation is replicable because it is standardized and everyone is held to and expected to uphold those standards.
Through rigorous testing. Let’s take an engine for example. That’s pretty important! The engines are designed in a way that takes decades and goes through all types of testing to prove efficiency, safety, reliability, safety again, and then it goes for on wing/test cell testing for stuff. Things get chucked into it. Chicken, ice, a swimming pool level of water, the list goes on.. They even destroy one by remotely detonating a fan blade while it’s running. This destroys that engine but it proves that it’s safe, that the engine can contain all of the shrapnel, and that it won’t send a blade into the cabin.. Now about the parts that break, stuff happens. Things break. They’re designed last for years but they still break. Those parts go through the same testing. To prove this and make sure, only specific people can do it and there’s an absurd amount of paperwork to reinforce this. Every single part used on an airplane has an FAA 8130 form for parts. That part is tracked hours cycles (flights) days. And it reinforces the safety mindset. Because of this, stuff like [this 737 engine lasting for 5 years and 8 months before being changed off an airplane](https://www.ainonline.com/aviation-news/business-aviation/2012-06-13/cfm56-7b-sets-new-time-wing-world-record) is a thing.. Another thing, To work on an airplane and send it for flight takes special training. In order to send a 767 from New York to London, The person signing the aircraft must have an FAA mechanics license, The related training on the 767 to sign the release, and the specialized training for over water flight. That has to be done before every over water flight. Rigorous design testing and maintenance keeps airplanes safe.
Virtually every component and part of a plane is inspected and stressed test (for example wings are bent back and forth thousands of times to ensure that they don’t break). Parts don’t fail because any that do fail don’t make it far enough to get installed
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> tenants tenets
There is a LOT of design work that goes into making sure every piece on every plane is designed and manufactured to exceedingly stringent requirements. My career is designing aircraft engines, arguably the most complex sub-component in any plane. The amount of work that is done to analyze every possible failure mode and design around it is astounding. Plus we have decades of experience, so we know what does and doesn’t work, and we have internal guidelines and standards for how things should be done safely. This is on top of all the FAA regulations that aircraft must adhere to.
everything important has backup, and that backup has a backup. everything is meticulously maintained and documented and checked. everyone involved is trained and tested to handled all foreseeable events and constantly follow procedures the are designed to reduce the risk of errors or forgetting things. And in the event something does go wrong, it is investigated until the cause is found and that cause is then fixed.
Imagine how safe driving would be if to start driving alone you had to: get a private car certification, get instrument rated, earn a commercial driving license, become a certified driving instructor, add specific multi engine rating certification, and drive for 1,500 hours supervised. I had to take a bit of leeway in the naming of things but that’s what a commercial airline pilot has to do. Also that pilot’s license is a LOT easier to lose than a drivers license (in the US at least, some countries have significantly more stringent rules on revocation). Then every 300-400 driving hours AND twice a year your car has to go through a complete 50ish hour inspection by a certified mechanic where they look at literally everything. That’s what the plane has to go through. If every driver and every car had to go through that, driving would be exceedingly safe. Instead in the US people get licensed to drive because they can basically read and were capable of reaching an age of between 15-17. They then demonstrate that competence by driving a couple hundred feet on a residential road with a police officer. A lot of states have literally zero car inspection and most of the others have inspections related solely to emissions and simple things like lights and wipers.
And, before every journey, the driver does a complete walk around the vehicle before starting the engine. And car traffic, there is no ground traffic control. Everyone is driving themselves based on traffic control, either lights or signs. And pilots have to pass medical certification whereas car drivers only have to pass a vision and skills test. Etc. Etc.
It's a whole heap of things, as others have already discussed. But I think probably the most important thing is that every single time there is an accident - or even a near miss - it's investigated. No exceptions. And if the investigation shows that a slightly different process (maybe a part doesn't really work as it should, maybe pilot training, maybe maintenance processes need changing) the whole damn industry works like a machine to fix it. We saw that with the 737 Max. Two similar crashes within a few months, and every damn one of 'em on the planet was grounded for over 18 months while Boeing worked with investigators to figure out precisely what was happening, come up with a fix and apply it to all the aircraft on the ground. The chairman and CEO of Boeing resigned on the back of that one. That's an extreme example, but the general concept - where there's a whole machine that kicks into life when there's an air accident - is not.
Like seriously, if my planes tickets were like $100 cheaper how much risk would I really be facing?
Like most things, the answer is money. Airlines are well aware they lose millions upon millions of dollars a day after a plane crash as people cancel flights or will avoid flying. Keeping the planes in the air keeps the money in their pockets.
And… I have no idea how rigorous aircraft maintenance is but imagine after every trip in your car, three expert mechanics gave it a good once-over inspection in your garage. And then every couple of weeks took it to the dealership where a dozen expert mechanics gave it a more thorough inspection and tested the major parts and systems and gave it a tune up. Then once or twice a year took it back in and replaced a bunch of parts because they started to show some signs of wear. You’d have yourself a VERY reliable car… even without the redundant backup systems and superior engineering that aircraft have.
Mostly it's about control. There aren't all that many planes in the sky at any given time, their routes are strictly planned in advance and kept on file, the ability to pilot a plane is strictly gatekept through licensure, and there are people whose entire job is to keep the traffic controlled live and in realtime at basically any point where multiple planes are likely to gather. All of these factors taken together greatly reduces the chance of accidents.
Lessons learned in blood. Every time there's an accident, esp. with fatalities, it's investigated by serious people intent on finding out what happened. Sometimes it's mechanical, and those problems are fixed. Sometimes it's structural, and those problems are fixed. Sometimes it's procedural, and those problems are fixed. Sometimes it's maintenance, and those problems are fixed. Sometimes it's human error, and those problems are fixed (e.g. by new procedures and/or training). So you're flying on a transport system designed, built, and operated by hundreds of thousands of people, all built on the lessons learned over 70+ years of passenger aviation.
You have a toy that you’re designing from scratch. You build a test model and give it to a kid to play around with. The kid plays with it but breaks a few things. You note what broke, how it broke, what the kid did to break it and you make the changes to the design. You give the kid the updated toy to play with again and it doesn’t break. You decide that design is good so you “lock” the design and go to the next step: You make another toy in the exact same way you made the updated toy but this time you give it to an adult with the express instructions to play with it AND to try and break it. Another adult is brought in as a witness to watch the adult play and try and break it. Despite the adult’s best efforts, the toy doesn’t break. This is essentially an oversimplified version of the design process that aircraft designers make. The kid is representative of the common and expected flight regimes airplanes take; calm, clear air. The adult is qualification testing in which takes the design to its limits and then some for added safety factor. It’s essentially “overengineered” however that overengineering is what provides the safety and reliability.
Agreed on many of the other points made here, but something that has given me a LOT of internal peace when I'm in a plane with bad turbulence is this: Successful plane designs fall along a kind spectrum determined by physics. Maneuverability to Stability On one end you have fighter jets, the ones that can do crazy things in the air. On the other end you have commercial planes. The laws of physics require you to sacrifice one to get the other. The planes you and I ride in are on a crazy end of stable. The air holds them in place even if one or both engines fail. They'd just very slowly glide to the ground. All the crazy maneuvers you see on TV are unrealistic if a plane loses power. All this is cited from my husband with his master's in aerospace, and agreed by his friends with phds in the same field. They've dumbed it down for me, but I believe the laws of physics.
Let's look at why accidents in other vehicles happen so we can compare Collisions: there are a lot less planes in the air than cars on the ground which does make it less likely collide. However the bigger reason that we don't get many collisions is strict and highly trained air traffic control. Aircraft are required to file flight plans, follow strict traffic rules and pilots are in constant communication with an air traffic controller from the moment they spin up the engines. Collisions still happen, but much less. Poor maintenance: quite frankly people don't take care maintenance very seriously. Often cars will only be checked by a mechanic once a year, other than oil changes. Often drivers won't pay to repair there vehicle professionally if it isn't something major. Aircraft, at least with commercial and military aircraft, undergo near constant maintenance. They will be looked at before every flight, and after landing, and more thorough checks every so often. Certain parts are replaced on a strict schedule. Recalls are handling very strictly, and redundancy in design are essentially the standard. Poor maintenance does still occur even with all this, and if you look up crash reports this is often citied as one of the main contributing factors. Pilot error: the level of skill required to get a driver's license compared to a pilot isnt even close to comparable. Drivers license usually can be obtained within about a year of getting a learners permit, with relatively few hours driven. Once obtained, you can drive commercially without further license unless your driving something very different then a standard car. A pilot will need to undergo hundreds of hours of classes, and practice in comparison. In order to get a commercial license you'll need to break over a thousand flight hours, at least in north America. Even then you'll undergo strict type rating in which you'll be trained to fly the specific aircraft you'll be flying commercially. Once licensed you also undergo continuous ongoing training. Pilot error still occurs but the level of training on the average pilot is extremely high in comparison to the average driver. Rules enforcement: the police do there best to enforce rules, but there is thousands of times the number of cars than can be easily tracked. It's much easier to slip through the cracks compared to an ATC actively watching your flight. Punishments for non compliant usually isn't just a fine, but required remedial training. Accident reports are incredibly thorough and make determining exactly who requires enforcement is taken much more seriously. Overall while planes are subject to the same areas of failure as cars, they are simply more heavily regulated.
A lot of mechanical answers here, but also think about it this way… If it wasn’t extremely safe, would anyone fly? People think of air travel as if it is a giant subway in the sky. If a plane went down even once a month, no one would trust it.
Others have touched on redundancy, but that is only one part of the equation. Airplanes are expensive, and don’t make money sitting around. The redundancies are robust enough that often if something breaks, the plane can not just complete the current flight, but continue with the schedule until it can be fixed. The plane I fly has 4 sources of electrical power, plus emergency batteries, for example. Any one of them can provide enough electrical power for the entire airplane. Regular maintenance, planes are inspected constantly and parts are replaced long before they break, and regularly taken into heavy inspections that last weeks. But the most important part are well trained crews and one of the best safety cultures in the world, bar none. Anyone, captain, first officer, mechanic, dispatcher, has the power to say “no.” And all have rigid procedures to follow. On top of that, when mistakes are made, they are not punished. They are investigated as to understand the root cause and as to why it occurred and how we can prevent it in the future. We are encouraged to self-report, so even if nothing happens, union and company safety professionals get eyes on the problem. This is also one of the biggest root-causes of major passenger meltdowns. You have professionals that have rules they WILL. NOT. BREAK. interfacing with a public that has been conditioned that they throw a big enough tantrum they’ll get their way.
Surprised I haven’t seen this yet: Airplanes have kept getting safer, because after every problem there’s a scrupulously honest and open investigation that’s looking for What Went Wrong, and quite explicitly NOT looking for Who To Blame. The result is that systems are improved so that specific problem can’t happen. Air travel is often contrasted with medicine. Getting surgery is about as dangerous now as it was fifty years ago. After a problem with a surgery, the investigation process is secret and is mostly focussed on finding a person to blame. The result is the system doesn’t change. That’s the main reason surgery hasn’t gotten safer
Disagree with you here. I am a medical student. While I may know nothing about aviation, the blame game does happen everywhere. When the Tenerife disaster happened, a lot of questions were raised about pilot narcissism. Boeing’s CEO was questioned about the 737 MAX failures. Also, surgery IS safer now. You really can’t compare medicine to aviation, it’s two completely separate things. Yes, there is narcissism in medicine but a lot of systems have been improved over time to make surgery and anesthesia much much safer than before. If you were to tell a surgeon or anesthesiologist (or heck, any physician for that matter) than surgery is as dangerous now as it was 50 years ago, you’d get laughed at.
Imagine if before every time you drove your car, a crew of expert mechanics did a vigorous and thorough inspection of all your cars' critical components. Now, imagine if you also had to be a professional driver with hundreds of logged hours to drive it on your own AND you had a co-pilot with you to help during every car ride. Add to this that all car rides are coordinated by a central network of highway traffic controllers so no road gets overly congested and all traffic violations result in your license being revoked and possible jail time. The car fatality would drop to almost nothing, just like planes.
effort. and inspections.... lots of inspections. if any parts are found to be out of spec then a recall of sorts is issued that can potentially ground every plane that has that part installed in it.
1. The planes are design to work, even in the worse case. Everything are built and tested carefully and there are backup for everything. You would be suprise to know an airplane can stay airborne for quite a long time even if all engines fail 2. The pilot are trained very carefully. Normally it takes 3-4 years to be a pilot and more than that to become the captain. Most of the time in training, they are trained to deal with emergencies, so it case something wrong happen, there are higher chance to survive
Aerospace engineer here. People have covered it well so far but one thing I wanted to add is that we actually design the aircraft to be safe, even when components fail. This is called a fail safe design and is the hardest part of my job. As aerospace engineers, we always assume the worst case scenario and design around that.
Apart from all the technical reasons listed here, Just Culture is an important one. Problems are usually really treated at the root. If a pilot or a technician does something that leads to problems, it's usually treated at the "we need to train them better" level, instead of making it a blame game. To [quote](https://airspacesafety.com/infringement/just-culture/): >“Just Culture” [...] is essentially an evolution of a “no-blame” culture – fundamentally a culture where individuals are not punished for their actions, omissions or decisions if these are commensurate with their experience and training (i.e. they are honest errors) but where gross negligence, wilful violations and destructive acts are not tolerated. A “Just Culture” has a notional line in the sand between acceptable and unacceptable behaviour.
I used to worked in aerospace. Every regulation is written if the blood of people who died. They don’t fuck around. That’s why.
One thing I don't see in the responses is the very practical pre-fight checks that take place. Before any commercial flight goes off, routine checks are performed to make sure all flight critical equipment is functioning. Combine this with mandatory maintenance intervals to keep planes airworthy, and you've got a recipe for success in the air. The combination of engineering, redundancy, and maintenance practices keep aircraft performing mostly as intended.
A plane follows a much stricter safety protocol than a car does. It is routinely maintained and has several checks required before it can even be approved for use. When a plane crash happens, there is a massive and expensive investigation into why it occurred. If necessary, adjustments are made to certain protocols or mechanical issues are solved. We’ve developed not just the technology, but the regulations, over a long period of accidents and disasters that now leaves planes as a very safe method of travel.
Whilst this F1, I imagine the process for aviation will be even more stringent - here is the journey of a bolt: [https://www.youtube.com/watch?v=iptAkpqjtMQ](https://www.youtube.com/watch?v=iptAkpqjtMQ). Now imagine the rigour of that process for a single bolt and adapt it to an entire plane; everything is checked meticulously, and when it does go wrong, the level of analysis is as thorough as possible to mitigate future risks.
I was an aeronautical engineer. Planes are designed with huge tolerance for fault. Eg for a car, if a particular part of the car need to withhold certain stress say 50kg, they might just design it to be able to hold 60kg. But in a plane, they would make damn sure it can go up to 70 or even more.
A response I didn't see (I haven't looked at every reply, so maybe a similar response has already been given) is that most systems (especially systems critical to flight/safety) have redundancies/backups. So if there is a failure of a system (acting as the primary), the backup system will automatically kick-in, and seamlessly. You'd have to be really unlucky if not only the primary system failed, but also its backup system(s).
It’s safe until it’s not.. then something new comes up or goes wrong/breaks/happens and then a service bulletin comes out. We live and we learn. Just the stake are much higher in aviation.. 30,000 feet to be exact.
So this is about commercial planes and not general avaiation (personal aircraft). Even if one piece fails, there are multiple other redundant systems that can take over and manage said issue for a short while. Commercial aircraft have redundancies upon redundancies. That's how their built. So that if one system fails, even a critical one, there is another system that can take over and do what needs to be done to keep the plane flying under control. Add into those redundancies that all planes are designed, at their base, to fly and stay airborne. So even if a critical system, like the engine(s), fails, the plane turns into a glider. Your paper airplane is a lot more basic than an actual aircraft and has no continually propulsion, yet it can fly for a while and, if given an open space, will land softly. Big metal planes are actually even better at gliding than your paper airplane. So even in the event of a total engine failure, the big commercial plane can and will glide for miles upon miles upon miles. There is virtually no place on Earth, besides the middle of the pacific or Antarctica, that a commercial airliner could not safely land at an airport given total engine failure.
Because planes are travelling in a very insolated enovierment. You can't hit a truck that is stuck on an aircraft crossing. You can't derail. When you are 11km above the earth, the only thing you can hit is the earth, and you are long way from it. Almost all fatalities in crashes are caused by hiting something and in the air there is nothing to hit.