Questions about high altitude props

[EdwardB3020]

I was experimenting with high altitude propeller assisted launch vehicles for low eve orbit. I can just about reach 20k  in height before loosing speed and flipping out. The propellers don’t rotate the craft and are at the com. They are constantly getting fed power so I don’t see what I’m doing wrong. I want to be able to reach 30k or higher to save vessel mass but I was wondering if anyone has help for this issue. Also the launcher can go into orbit. It just needs props that can go that height. 

[Kimera Industries]

Well there is an altitude limit for propellers, they are basically tiny wings after all. The general rule of thumb is the higher altitude flight, the faster you have to go. On Eve this is made much easier by the dense atmosphere, but there is still a limit.  If you are trying to get a contract on Eve at an altitude above 20km (which is my exact scenario lol) then all you need is a temporary boost in speed to get to the proper altitude and maintain flight. 

Try some twitch engines (small, radially mounted to save node attachments) and some small fuel tanks. Pros: high thrust Cons: horrible fuel efficiency, dead weight when fuel runs out. This will work if it's only like 4 contracts, but not if you want sustained flight for extended durations. If you want that, you could try...

More propellers. At a higher altitude, with less air, they won't work as well, so if you add more, they might make up for the loss in efficiency. If you haven't, try adding solar panels on the wings (the OX-STAT non-deployable kind) to fill the electrical requirements and try finding ways to fit in more wing area. Pros: sustainable flight might be possible, goes much faster at a lower altitude Cons: higher launch mass + payload size

Hope this helps, at least it's not like my earlier attempts at Eve planes before there was a DLC and it all had to be rocket powered...

EDIT:

Oh, I just reread that and I see you're trying to do a launch assist plane to get to a low orbit. (Not sure if that's the actual name for it but it works)

If you don't have mods for that you'll lose the plane when you switch to the craft that gets into orbit. Unless the rocket itself has propellers on it? Can you describe your launch vehicle or post a picture, that would help a lot.

Edited May 5, 2023 by chimera industries