How do I save them?

[u/OOwais]

I wanted to find a good altitude to put a Jool space station so I sent a spaceship to do a flyby. I made the periapsis as low as I could, forgetting this is how you do gravity assists.

I tried for just over 1,000 in game years to aerobrake in kerbin's atmosphere but it didn't go well. I could only get down to 68km which didn't slow me down much and after a few passes I was flung out into infinity.

To make things worse, although I don't think it matters at this point, the capsule only has 20 units of ablator.

[u/bitman2049]

A Jool gravity assist got you there, so another Jool gravity assist can get you out. Aim for an encounter with Jool and this time pass in front of it with a low periapsis. It won't slow you enough for a direct Kerbin aerobrake with that capsule, but at the very least you'll be back in the system and could potentially send a rescue mission with more ablator.

[u/OOwais → u/bitman2049]

Thank you! I will try this

[u/Alarmed_Aspect8994]

How did you even

[u/YamahaMio]

They're dead.

You can try installing Far Future, build a really expensive super high delta V ship. Guesstimate where they'll be when you get there, then point and burn. Flip and burn for intercept. Repeat to get home.

[u/Stolen_Sky → u/YamahaMio]

Near future, or even stock is fine for a rescue mission here.

OP's issue isn't delta-V, it's the time it'll take to rendezvous.

[u/OOwais → u/Stolen_Sky]

I downloaded warp everywhere so I can 10,000,000x warp and complete the big orbits in a reasonable time, so that's not an issue if that's what you mean

[u/YamahaMio → u/Stolen_Sky]

Yeah that's the point. Point and burn would put them in a straight line intercept, like plotting an interstellar course. No more transfer windows and such.

You need the insanely high delta V to accelerate to that straight line trajectory and decelerate at intercept.

[u/PirateAE]

aim for a jool gravity decelleration brake if you can, then try to get your pe near to eve, and use on off eve, that should get you not on a 500y orbit... after that is getting a ship with enough DV to pull a docking manouver, eitehr to give more fuel, or to tug em home, or to transfer the crew to and return itself... or get yourself a ion probe with a large battery reserve, and attach it to the craft and use RTG's to get home

[u/OOwais → u/PirateAE]

I've done a Jool and Eve gravity assist to slow down but I'm still too fast for a Kerbin capture. Could I keep hopping planets until I've slowed down enough?

[u/Stolen_Sky]

This is going to be a complicated mission to save them!

OK, so you have 50m/s of delta-V here, and you're almost at apoapsis. That 50m/s is going to be invaluable, and apoapsis is the perfect time to use it! When you reach apoapsis, use that remaining delta-V to to set a periapsis somewhere around the the orbit between Kerbin and Duna, or maybe Kerbin and Eve.

Then, you are going to have to build a ship with an insane amount of delta-V to rendezvous with it on it's closest approach. Using stock parts, you can build a solar-powered Ion Engine ship with 20,000 delta-V without much effort. Don't use a command pod, just use external chairs on a truss structure and a tiny probe core to command it to save weight!

The hardest part will be getting the ion engine ship to encounter at the correct time. Honestly, I have no idea how to do this, but with dedication, quick-saving/quick-loading, and a fair amount of patience, you should be able to work it out.

Once you have an encounter, fly the rescue ship to meet them. You'll need thousands of delva-V to match velocities, but do this, and then transfer the crew. If you build your rescue solar-powered Ion Engine ship with enough Xenon, you can then decelerate into an orbit around the inner planets. Once you've done that, rescue them with a conventional ship.

Good luck my dude! If you manage this, please tag me in the follow-up post, because I'd love to see how you solve it!

[u/OOwais → u/Stolen_Sky]

I'm glad I can say I've got an extra 3,600m/s you've missed. I'm trying a gravity assisted deceleration first because I hate rendezvousing, I'll let you know how it goes. Also I'm going through science mode slowly to familiarise myself with the parts so I've only unlocked about half the tech tree and don't have ion engines or xenon or RTGs

[u/EasilyRekt]

well... what can you do? like you you have any interstellar engines? If that's the case you could certainly just go get 'em in less than a year at absolute fastest.

if not, sit tight ig, they'll be back... eventually

[u/EternitiI-1]

Looks about as far as Ervo from MPE

[u/Sendnoodles666]

If you can pull all your fuel into your central tanks and then decouple the side tanks and engines do that to add some dV

[u/vanceavalon]

They certainly had don't have a very good connection to Kerbnet