Aerobraking/Aerocapture

[Crikeycrapper]

I'm currently running a Eve probe convoy mission designed to farm science from Eve and Gilly. Two of these probes, creatively named Eve-1 and Eve-2, are designed to use Eve's atmosphere to capture into its SOI. I really don't know the perfect altitude for aerobraking on atmospheric planets, but all I know is that if you go too high, you won't get captured and if you go too low, you will have unplanned lithobraking. Info is advised for all atmospheric bodies. Thanks KSP community for your help!

-Crikeycrapper

[cybersol]

Its hard to give rules of thumb in the new aero, because the window between not getting captured and landing too early is fairly small. Combine that with the fact that drag depends on the shape and orientation of your craft, and you end up will something like trial and error being your best bet (F5 to save/F9 to load). If you want to avoid save-load you will want a mod that can predict your trajectory in atmosphere, like Trajectories or MechJeb. Even those mods only give estimates, but they are close enough to plan things around.

[Empiro]

If in doubt, aim high and just skim the atmosphere. If your orbit doesn't close and you've passed PE, just do a bit of a retro burn. Note that it only takes about 80 m/s to capture into an elliptical orbit, and at that point, you can bring your AP down slowly with multiple passes.

[Crikeycrapper]

Thanks for the help guys! Just aerocaptured into Eve at 65km periapsis, and apart from fried comms, the probes remained intact! (antennarange user so maybe partial success?)

-Probes had 1.25m heatshield in front

[cybersol]

If you put the comms inside the orange glowing cone created by the heatshield, length-wise before the end of the flames, then that should help protect them (KSP models a short sonic shockwave cone of mild protection). I also sometimes include a backup antenna inside a service bay for craft that need extreme aerobraking.

[DBowman]

Mechjeb's Landing Guidance can be used as an aerocapture aid. Just open LG and click 'show landing predictions', there are a few options you can play with but basically you can adjust your Pe and if you are entering the atmosphere and not hitting rock it will tell you what orbit you will end up in. I've not tried it in1.0.2.

[MarvinKitFox]

EVE, coming from a Kerbin transfer orbit:

about 73km will suffice to just capture you, putting you in a highly eccentric orbit without burning anything off other than *deployed* solar panels.

From this orbit you can easily go to Gilly, or do a handfull more aerobrakes to enter a lower EVE orbit.

Anything below 70km will put you in a closer eve orbit, but requires attention to heat shielding.

Below about 63 km is attempted suicide.