Question About Mechjeb2

[ZooNamedGames]

I have a question about Mechjeb2's ascent feature. The question being, if I were to launch a space shuttle replica, would MJ know to roll over onto the shuttle's back so that the thrust is correct? Or will it just pitch over and let the shuttle fall back because the thrust is towards the ground and not the sky (inverted launch(shuttle on top))?

[Technical Ben]

You can set a "force roll" option. You would have to set the correct roll (I think MJ2 supports this), else set a port/etc that has the correct orientation as the "control from here" part. Launch in the orientation you want, and then MJ2 will roll over to the other way (upright I think).

So I guess you may need an upsidedown docking port/probe core and set it as the control point. Mechjeb might roll early too, but it would be close to the desired effect.

[ZooNamedGames]

You can set a "force roll" option. You would have to set the correct roll (I think MJ2 supports this), else set a port/etc that has the correct orientation as the "control from here" part. Launch in the orientation you want, and then MJ2 will roll over to the other way (upright I think).

So I guess you may need an upsidedown docking port/probe core and set it as the control point. Mechjeb might roll early too, but it would be close to the desired effect.

Alright. I'll give it a shot.

[Axelord FTW]

Alright. I'll give it a shot.

In this case, the roll will be 180.

[Wolf Baginski]

MechJeb has a roll option in the Ascent Guidance window, and there's no need to do anything fancy with command pods and probe cores. They can matter if you want to land a vehicle with sideways-facing rockets, but something like a Shuttle is just like any other spaceplane for landing. The system doesn't care whether you assembled it in the SPH or the VAB.

On a manual flight, the navball starts with north at the top, and you could either adjust the gravity turn with the yaw control or manually roll and then use pitch. This MechJeb roll is independent of the turn to match orbital inclination.

[Randazzo]

Having a couple small shuttle designs under my belt, I'd advise against trying to use Mechjeb ascent guidance. It's possible to force it to work, but it's more hassle than just flying it up yourself (and I say this as a Mechjeb fanboy). If you absolutely must use Mechjeb to do it, use the Surf setting and manually enter your heading and adjust it little by little as you climb. Also, don't be shy about the Verniers.

Edited September 3, 2015 by Randazzo