Keep auto-pilot active when switching to another craft?

[KissSh0t]

Is there any way to keep auto pilot active when switching to another craft?

I've made a two stage air breathing jet / space rocket.. basically it is a very fast air breathing jet UAV with a manned space jet attached on top of it.. and I am trying to launch the space rocket from the air breathing jet, then switch back to the air breathing jet and land it, then switch back to the space rocket and fly it in space..

But when I do this, the auto pilot turns off on the air breathing jet and by the time i have switched back to it, it is tumbling out of control and is impossible to recover due to it's design.

Is there any way of keeping the first aircraft flying strait and level while I'm focused on the second?

[KissSh0t]

I guess no one knows or it's not possible =_=

[nhnifong]

ASAS will stay on when you switch to another vessel.

[stupid_chris]

The thing that is putting your jet off track is the sudden loss of weight, your CoM probably switches to a much further position from your CoL than it was, your plane becomes unbalanced, wants to get its nose down or up, it's too much for the ASAS to handle and it goes tumbling. Its frankly quite normal than this happens.

[Nibb31]

ASAS or MechJeb or any other autopilot can only work if the other vessel stays within 2.5km. Even then, it doesn't seem to work 100%.

The easiest way to deal with this is to press F5, fly back your booster, then press F9 and fly your mission.

[HoY]

With the Lazor plugin and MechJeb 2.* this is actually possible. Provided a few things are happening.

First with Lazor plugin settings at KSC set your load distances all to the max. There's a quick button for this. I think it's something like 90km.

You'll need to have MechJeb spaceplane guidance set to hold your altitude, preferably above 30km if you can get your air breather that high.

Now as soon as you decouple your rocket (assuming the rocket was built on top of the plane and not the plane built under the rocket) you should still be in control of the air breather. Use the [ and ] keys to switch over to the rocket. Do not time warp and do not exit to the tracking station as this will break mechjeb's control.

Quickly get your rocket into the bare minimum orbit, remember if you get more than physics distance away from the air breather you'll be racing against the clock to get back to it to recover its decent.

The safest bet would be to just get an apoapsis above 80km, check how long you have till Ap, then let the rocket drift while you land the airplane.

Tab back over to the airplane and keep in mind how much time you have before the rocket starts to descend again. Plan your landing site (it won't be KSC unless you orbited kerbin in atmosphere and its now ahead of you)

The quicker you can get on the ground the better!!! You can use the tracking station to switch back to the rocket now that your not relying on physics load range for MechJeb autopilot.

Anyway, you get the idea. Let us know how it turns out

[John FX]

The only way I can think is if the rocket section boosts (within 2-2.5km of the plane) to get an Ap long enough away that you can land the plane then switch back in time to circularise your orbit.

[KissSh0t]

The only way I can think is if the rocket section boosts (within 2-2.5km of the plane) to get an Ap long enough away that you can land the plane then switch back in time to circularise your orbit.

Ahh yes.. this is what I am trying to do, I get the small rocket vehicle nearly circularised around Kerbin, then switch back to the launch aircraft, but it's engines have switched off and it's auto pilot is switched off, even though I had them on before separating from it.. I then try to regain control but it's the sort of craft where it is impossible to recover from a flat spin.

So I'm guessing you can't keep the auto pilot flying the second aircraft when you are using another craft.. That's a real disappointment..

[John FX]

Ahh yes.. this is what I am trying to do, I get the small rocket vehicle nearly circularised around Kerbin, then switch back to the launch aircraft, but it's engines have switched off and it's auto pilot is switched off, even though I had them on before separating from it.. I then try to regain control but it's the sort of craft where it is impossible to recover from a flat spin.

So I'm guessing you can't keep the auto pilot flying the second aircraft when you are using another craft.. That's a real disappointment..

Have you thought about maybe trying it the other way or with mechjeb? I know mechjeb will run when switched and most rockets dont go into flat spins with ASAS on, you could be in the jet, decouple the rocket, switch briefly to the rocket, tell mechjeb to get to orbit, the rocket will thrust, switch back to the jet (not sure if this will work) andmechjeb should keep thrust on, try to keep up in the jet to get the rocket as fast as possible before you go over 2km then hope the rocket is still out of the atmosphere by the time you land the plane.

[Kegereneku]

The problem is that KSP only calculate physic for the focused ship, meaning that you can't have any sort of maneuver outside the 2.2km radius around your ship.

As stated earlier the only solution seem to be to circularize FAST before the airplane hit back atmosphere, disappear as a debris or lose control.

This is also what make impossible (for now), reusable rocket for which the first stage are expected to para-land automatically.

A shame because I want to try the SpaceX crazy concept.