Mechjeb Landing. Flips at 10k feet

[xlilcasper]

So just getting back into KSP. Haven't played since 0.22. Installed MechJeb and built my first rocket. The mission. Get into orbit and then land on the launch pad.

So launch has no issues. Get into orbit and then I bring up the landing guidance. Set target and go. Everything works well until at about 10,000 feet in which instead of going burner first, my craft flips and starts going nose first into the ground. It get close, deploys the landing gear then smashes face first into the ground at around 200 m/s. :/

I have tried lowering my center of gravity of the landing portion but no luck. I still get the flip at about 10k feet. Here is a pic of my craft.

Anything I am missing? Any reason that this would be happening. I recall from 0.22 that landing with mechjeb was normally spot on and without issues.

[Randazzo]

This is due to the aerodynamic changes in 1.0.x, it's not mechjebs fault. Looking at your ship, I'm guessing that as the fuel burns down, the capsule end becomes heavier than the engine and as a double-threat, is more aerodynamic. Weight and drag are combining to flip the vehicle over.

Try flying it yourself to get a feel for it.

And I'm saying that last part as a mechjeb user myself. If it feels pretty much impossible to do manually, chances are mechjeb can't do it either.

Edited June 2, 2015 by Randazzo

[WOODY01]

MechJeb has had some problems with some of my designs that I can fly manually just fine. With those designs I take over when MJ is having trouble then switch back to MJ.

With landing on Kerbin most times I let MJ do the intial burns and the corrections at high altitudes then I take over.

[xlilcasper]

This is due to the aerodynamic changes in 1.0.x, it's not mechjebs fault. Looking at your ship, I'm guessing that as the fuel burns down, the capsule end becomes heavier than the engine and as a double-threat, is more aerodynamic. Weight and drag are combining to flip the vehicle over.

Try flying it yourself to get a feel for it.

And I'm saying that last part as a mechjeb user myself. If it feels pretty much impossible to do manually, chances are mechjeb can't do it either.

I think you'r right on, I feel it is a weight issue and it being top heavy. May have to expand out to the sides with me fuel instead of in a column design? I definitely think it is a design flaw rather than a mechjeb flaw.

[Tex_NL]

Move the RCS tank and battery down to below your fuel tank. It won't interrupt fuel flow but might keep the CoG low enough once your fuel is drained.

[*Aqua*]

You can also add fins, stabilizers and airbrakes to the top of the rocket. On ascent you shield them with the new fairings. On descent you use them (or let MechJeb do it) to keep your craft under control.