Rescuing pilots in solar orbit...

[LurifaxFlux]

Has anyone done it before? or something similar?

If so, how?

Well, I've been playing about 1 day now, 24 hours non stop, and I have ended up with 2 pilots in solar orbit between eve and kirbin.

I really want to recover them (one has been orbiting for over 6 years now hah) but I can't seem to get close. the closest I got was 5k Km, that is about 0.01% orbit diameter or even less, and that is still a huge distance, way too far to just fly directly towards it, I'd just be thrown out of orbit into nothingness.

Also, I haven't "discovered" small docking systems yet, so I have to move the pilot from the dead vessel to the rescue one by means of EVA. (I succeeded in doing this in another rescue mission in orbit around mun).

Anyone interested in helping out? One pilot is orbiting the sun

[Killerdude8]

It's the same as any other form of rendezvous, except it takes much longer to align them.

Protip, don't waste time on a solar orbit rescue. Usually take too long and too much effort to be worth it.

[Agent86]

Cyanide pill and a really pretty memorial service.

[Unfawkable]

You sure you can't do it within 5 Kms, that sounds quite enough for a ship rendezvous? I haven't personally attempted this, but it's quite possible, you just need to practice that intersecting a lot I guess. I have 2 guys around the sun that I plan on rescuing one day

Edit: Oh, 5000 Kms, nvm then.

This tutorial helped me understand ship rendezvous a lot, so it might help you too. It's only Kerbin orbit, but take a look.

Edited November 18, 2013 by Unfawkable

[Epthelyn]

Wait for Kerbin to pull them back? I'm not entirely sure what is what in that picture, but everything seems to cross Kerbin's orbit, which means eventually something will enter its SoI. Then it's just a case of getting out the EVA jetpacks and pushing to circularise

[magnemoe]

In solar orbit, to lesser degree in high Jool orbit its hard to get within 5 km of target, however this is no big issue, remember that you use an year to do an orbit around the sun, not 30 minutes so in practice you are in flat space, say you end up 200 km from target, burn to get zero relative speed, do an burn towards target say 50 m/s toward it, you will get an new intercept in an hour so warp until your trajectory is different from target direction, stop and burn again but less this time, repeat until you are in docking range

[maltesh]

I recently wound up dusting off my old "Disasteroid: 200 days to Impact" scenario, updating it to 0.22 compatibility, and flew a rendezvous with an asteroid in an inclined, elliptical orbit around the sun.

The three things I really wound up taking away from that, and previous large-orbit rendezvouses:

0. Accept a much larger close-approach distance than you would in Kerbin orbit. I used maneuver nodes on the rendezvous and ultimately decided that 50,000 km was a close enough approach that I could fly the navball to perform refining corrections to shrink three to four days before arrival.

1. You can switch to target-relative velocity at any time that you have a spacecraft targeted. Just click the navball. If you wait for the game to do it automatically, the game won't do it until you're within about 60 kilometers of the target, which is /ridiculously/ hard to do in solar orbit.

2. The game's in-game closest approach numbers are inaccurate. It's usually not that bad in LKO rendezvouses, but in the solar orbit rendezvous I did, they wound up being tens of thousands of kilometers off in some cases. Judging from the screenshots I wound up taking, the game tended to overestimate closest-approach distance by a factor of five or so. Any mod that gives more-accurate numbers on your closest approaches will be helpful in that situation.

3. Especially if you're rendezvousing with moderate-efficiency engines, you really need to understand how to maneuver the relative-velocity indicator onto the target-direction indicator /while/ you're killing relative velocity. Kill relative velocity - Burn towards Target - Repeat is conceptually easy to understand, and works, but it's going to cost you more delta-V than slightly tilting off the relative-velocity marker to push it onto the target marker. Remember that, on the typically-built spacecraft, burning the engine /pulls/ the pro-velocity markers across the navball towards the direction your spacecraft's nose is pointing, and /pushes/ the retro-velocity markers away from the direction your spacecraft's nose is pointing.

4. In the final phase, time acceleration is not your friend. I generally found that, when I finally did get within those last 2.3 kilometers of distance, /any/ time accelleration, physwarp or not, resulted in the target changing relative position by several hundred meters.

Edited November 18, 2013 by maltesh

[Kasuha]

4. In the final phase, time acceleration is not your friend. I generally found that, when I finally did get within those last 2.3 kilometers of distance, /any/ time accelleration, physwarp or not, resulted in the target changing relative position by several hundred meters.

Physical time warp is funny as the target will slide along its trajectory the more the higher time warp you choose, but it will return back once you reduce the time warp back to x1. So you can use physical time warp to traverse certain distance but do not trust what the game tells you about the position of the target during that time.

On-rails time warp is worse because it will move the target to some different place and it will not return. But according to my experience, it only happens once and subsequent time warp changes were way less drastical.

My rule of thumb is: until you're up close, keep your relative velocity at or below 1% of your distance. So if it's 20 km, you should not go much more than 200 m/s. If it's 10 km, you should be on 100 m/s already.

[Smidge204]

maltesh pretty much spelled it all out for you. I'd pay special attention to point 3.

I'd add that you should be especially careful when you're really close, like under 30 meters, as the exhaust from most engines can "blow" objects away. When you're about 100m or less, slow down to as close to zero as you can manage, switch craft (don't forget to re-set the target) and EVA yourself over. Even at a distance of several km an EVA is pretty straightforward as long as the relative velocity between craft is zero.

=Smidge=

[LurifaxFlux]

Protip, don't waste time on a solar orbit rescue. Usually take too long and too much effort to be worth it.

Cyanide pill and a really pretty memorial service.

Fuk. I really don't want to kill them but being an amateur I doubt I'll be able to recover them, reading all the stuff people wrote here.

In solar orbit, to lesser degree in high Jool orbit its hard to get within 5 km of target, however this is no big issue, remember that you use an year to do an orbit around the sun, not 30 minutes so in practice you are in flat space, say you end up 200 km from target, burn to get zero relative speed, do an burn towards target say 50 m/s toward it, you will get an new intercept in an hour so warp until your trajectory is different from target direction, stop and burn again but less this time, repeat until you are in docking range

at 5K Km I'd be consuming way to much fuel to get there in time and slow down.

_________

@maltesh:thanks for the tips. I think I might leave them in orbit until I have developed more sophisticated tech, then I'll re-attempt the rescue.