Spaceplanes on Jool

[cephalo]

So, I'm planning a mission to Jools lower atmosphere, and since I haven't been to Jool, I'm not sure what to expect. The orbital speed is quite high. In order not to cook my spaceplane, do I have to spend a bunch of dv to slow myself down before descending below 120k altitude? Maybe I just need a very shallow descent angle? Does anyone have an idea of what dv it takes to get back to orbit from 100k altitude or so?

[Geschosskopf]

All I can say is, good luck with that.  It would be an impressive achievement.  Huge heat, huge drag, huge dV.  Just guessing, I'd say about start with 5000m/s and see what happens.  Much testing with HyperEdit before you do it for real

[rocketbuilder]

That would be an interesting challenge! But 100km is a bit like the surface of Eve and that would be hard.

Make good use of vectors, mammoths, aerospikes, huge amounts of fuel...

Edited December 2, 2015 by rocketbuilder

[AeroGav]

Regarding the issue of power, you are handicapped because the stock engines only cater for

1) flight inside an oxygen atmosphere

2) vacuum

Inside a methane atmosphere, it would be possible to construct an aircraft that uses jet engines and carries only oxidizer, since fuel is literally everywhere.  Even given an inert atmosphere, a nuclear turbojet, ramjet or turboramjet should be possible.

With only the stock motors, you can't use NERV because the atmosphere is too thick or even Terrier, you'll be in closed cycle mode fighting atmospheric drag burning fuel and oxidiser getting less than 300 ISP.

Maybe look at a mod like Atomic Age (has nuclear turbojet),  or just mess around with engine config files in Notepad like i did in this thread -

 

 

 

[cephalo]

Well, my theory goes like this:

The wiki says that Jool's atmosphere is as thick as Kerbin sea level at 91,000 meters. So in the 120k range, it should be thinner than Kerbin at sea level. I also only need to bring down my velocity enough to not cook, so I'll be at 118k or so with about 1200 ms of velocity. All that should limit the dv requirement.

My spaceplane uses aerospikes and almost makes orbit on Kerbin from the runway. Maybe I need to make sure I can get orbit with dv left over.

I haven't used HyperEdit. It seems cheaty to me, but there's probably no other way to test my craft. Maybe I have to get over it.

[A35K]

8 hours ago, AeroGav said:

Regarding the issue of power, you are handicapped because the stock engines only cater for

1) flight inside an oxygen atmosphere

2) vacuum

Inside a methane atmosphere, it would be possible to construct an aircraft that uses jet engines and carries only oxidizer, since fuel is literally everywhere.  Even given an inert atmosphere, a nuclear turbojet, ramjet or turboramjet should be possible.

With only the stock motors, you can't use NERV because the atmosphere is too thick or even Terrier, you'll be in closed cycle mode fighting atmospheric drag burning fuel and oxidiser getting less than 300 ISP.

Maybe look at a mod like Atomic Age (has nuclear turbojet),  or just mess around with engine config files in Notepad like i did in this thread -

 

 

 

If you have interstellar mod, Jool's atmosphere is literally fuel, as the mod assumes that it is 95% hydrogen, and it also assumes that liquid fuel is hydrogen, so you can use these scoops an fill your tanks as you fly through the atmosphere!

[cephalo]

Another thing I'm looking at, is that Jool's atmosphere is quite a bit colder than Kerbin. I wonder if that means I can go faster without burning up.