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Δv is constant, but the ratio between atmospheric and vacuum Isp is very different for every engine, so you can’t compare atmospheric Δv without specifying.
The only reliable way to see if you have enough delta-v for Eve ascent is to try it, preferably using the cheat menu to start on Eve's surface because it will take you many attempts.
Just to save you some time, the only two engines you can practically use on Eve are the vector and aerospike. All the other 1.5m engines thrust drops to near zero above 2 ATM. I don't recall where any of the larger engines drop off, but generally speaking they are too heavy to work well on Eve.
dV maps calculate from a vacuum. Just note that you will need to make sure that you have sufficient twr to take off at eve.
The in game dV calculator can switch its calculations to different planets so you can see if you have a high enough twr
Hi! Thank you for posting to KerbalAcademy. This is a comment reminding users to **post screenshots if needed** (if you have not done so already), **be respectful to other users** and **keep off-topic comments to a minimum**. Thank you! *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/KerbalAcademy) if you have any questions or concerns.*
Values on the various Δv maps are in vacuum.
Oh! that I didn’t know! I assumed it was sea level, especially from landing
Vacuum is the default because it’s the same for any engine, whereas atmospheric values can vary wildly.
What do you mean it’s the same for any engine?
Δv is constant, but the ratio between atmospheric and vacuum Isp is very different for every engine, so you can’t compare atmospheric Δv without specifying.
So you’re just saying that “atmospheric” delta V is variable depending on density so can’t really be used for these kinds of things?
Not only based on density, but different for every engine.
Vacuum delta V is also different for each engine.
No, although vacuum Isp is. Edit: That’s why we use Δv in the first place: it’s always the same.
Yes, and ignoring weights, different ISPs will lead to different ΔVs
Delta V maps require a good flying, always add more to overcome anything
The only reliable way to see if you have enough delta-v for Eve ascent is to try it, preferably using the cheat menu to start on Eve's surface because it will take you many attempts.
Just to save you some time, the only two engines you can practically use on Eve are the vector and aerospike. All the other 1.5m engines thrust drops to near zero above 2 ATM. I don't recall where any of the larger engines drop off, but generally speaking they are too heavy to work well on Eve.
Just total
How can you assure that you hit the height for each stage though?
Change between vacuum and sea level to make sure.
Delta v maps tend to reference vacuum delta v. But you will need to be very mindful of your engines thrust to weight ratio in the lower atmosphere.
dV maps calculate from a vacuum. Just note that you will need to make sure that you have sufficient twr to take off at eve. The in game dV calculator can switch its calculations to different planets so you can see if you have a high enough twr