Minmus Rescue Imminent

[The Jedi Master]

OK, Whermie Kerman was on a mostly routine mission to Minmus to test the Nuclear Engine, and to measure the gravity on the moon while he was at it. This was the lander I designed. The observant will notice the problem:

Now, a simulation (AKA F5/F9). I was coming in for a landing, and this happened:

The force of the fairings blew apart the lander. I quickly reloaded the quicksave, and now Whermie Kerman is stuck in orbit around Minmus. I don’t know if the transfer stage alone has enough fuel to get all the way back to Kerbin, and I don’t want to take the risk. The ship has no docking ports. Looks like this is the day I finally learn how to rendezvous.

So, anyone got any tips to bring Whermie back home?

PS. The ship has exactly 666 units of fuel left. Foreshadowing?

[DMagic]

Do you mean 666 units of fuel in that big tank? That should be way more than enough to get back, or you could just blow that off and use the nuclear engine to get back. The 180 units of fuel in that tank should also be more than enough.

But if you want to do it the hard, more fun way, you could send up a small rescue vehicle. Put a 1 man command pod on top of a lander-can and use that to ferry back your stranded pilot. You could separate the command pod and just use the lander to return to Kerbin in, or just drag the whole thing back. Rendezvous shouldn't be too bad because you don't actually have to dock, slow down and get close enough to do an EVA over to the rescue vehicle.

[SoldierHair]

You have lots of unnecessary things on it.I would suggest for your next rocket to have a lander with nuclear engines on the sides and a normal one in the center.Use fuel crossfeed to consume only from the nuclear engine's fuel tank.You will have more thrust and in the same time more fuel + you will not need that landing gear system you created.I would also suggest the double sized (in lenght) fuel tank over the one you use now on the lander.

You don't have many options , if you said you don't have a docking port.It is land , bust or orbit.

Edit: As mentioned above , you could aswell send another rocket and drive the kerbal back home.

[Tw1]

Tried transferring fuel from the lander stage to the transfer stage? If you burn at the right point in the orbit, you should be able to get home with one burn.

Or,plot a burn so you'll have a Minmus escape in the opposite direction of Minmus's orbit. Increase it until the Kerbin periapsis disappears, don't worry about aiming for KSC, this is an emergency!

RCS can be used to do the burn too, if needs be.

Otherwise, you will have to send another up there, rendezvous, and EVA across.

I like the name. Whermie. Make sure he gets anther chance some day!

[Specialist290]

If that's a nuclear engine, then you most definitely have enough fuel to make it home on your own with just the lander -- nevermind the transfer stage. Nukes are absolute overkill for anything short of interplanetary missions.

[The Jedi Master]

The nuclear engine usually gets blown off with the rest of the lander, by the way. The fuel transfer is an interesting idea, though. How do I do it?

[Tw1]

Pretty sure the nuke engine broke of in that pic.

Edit: Saw your latest post.

Click on a fuel tank, to bring up the little display with its name and what it has inside it. Then hold Alt and click on the other tank, and you should get little buttons that let you move fuel and oxidizer between the tanks.

Edited May 16, 2013 by Tw1

[The Jedi Master]

This is KSC, cross-feed is complete. At what point should I do the return burn?

[DMagic]

I believe you want the point in your orbit when you are on the side closest to Kerbin and in the opposite direction that Minmus is moving around the planet. That is, if you are orbiting Minmus in the same direction that the moon orbits the planet (a prograde orbit, counterclockwise when looking down on the north pole). If you are in the opposite orbit then you would burn at the point when you are on the opposite side of Minmus, further from Kerbin, but still burning in the opposite direction that Minmus is moving.

[Tw1]

The burn must be prograde, and a little after when your orbit's prograde points you to Kerbin. Good luck!

Test with a maneuver node first.

[The Jedi Master]

*ksch* Searcher 1 to KSC, Searcher 1 to KSC, I have splashdown, I repeat, I have splashdown. *ksch*

Tw1 shall now receive the Medal of Honor from President John F. Kerman. Cue fireworks!

[Spatzimaus]

Good to see he got home, but you should know for next time: that 100-unit RCS fuel tank should have been enough to get the whole thing back, even if nothing else worked. To be sure of this, my own designs generally put the RCS tank and one set of jets ABOVE the final stack separator, so that they go with the capsule in case of emergency. That way, you have very little mass getting pushed by the RCS jets. But my older designs didn't do this, and it still worked fine. For instance, here's an OLD picture from my first Duna landing (my first successful trip anywhere, actually, as this predated my landings on Mun or Minmus):

It's actually a 5-stage rocket, with what you see there as the final two stages. The outer four pods separate radially, and I ditched them just before leaving Duna's SOI on the way home. The central module is one piece, and ran out of fuel right at around Minmus' orbit after circularizing around Kerbin. I made it the rest of the way home using only RCS, so I'm sure you could have made it home from Minmus the same way if your tanks had run dry. (Now, if you had no way left to empty those tanks because your engines broke, then that's a lot more weight to carry.)

[Tw1]

Tw1 shall now receive the Medal of Honor from President John F. Kerman. Cue fireworks!

Aww, nice!

*makes short speech about space stuff, and acknowledges the others also advising the recovery effort*

Good to see him back on his home planet. When he's recovered, I reckon send him up again.

You might be able to construct a frame using the I-beams that extends past the engine, for it to land on. Make sure the any trusses are solidly connected to the fuel tank, not the LV-N. If it managed to get home like that, it should be able to land, if you manage to solve the falling apart problem.

[DMagic]

Yep, a stack of I-beams works great for this, just make sure that the engine shroud doesn't get blown into the beams. You should be able to see the seam where the shroud splits apart and figure out which way to orient it.

You might have to fiddle around with the I beams to get it placed right, but it works really well.

[Pixel of Life]

Launch a small refueling ship, dock with the stranded lander, transfer some fuel and fly the whole thing back to Kerbin. Much more challenging and probably also more fun than just EVAing the kerbals to another spacecraft. You might even learn to rendezvous properly

[The Jedi Master]

Whermie did eventually make it to Minmus.

Yes, I know I went overkill with the landing legs.

Also, this is offically my 100th screenshot. You know you play KSP too much when...