Maneuver execution of Principia node results in additional ignition at completion

[Pablo49]

MechJeb Version

2.16.0.0-1644

KSP Version

1.12.5.3190

Description

Executing principia nodes in Realism Overhaul with mechjeb's maneuver planner results in an extra ignition at very end of the burn, using an additional engine ignition.

Replication Case

Video is an example of a basic Juno powered craft in LEO with a pure prograde principia burn. Video shows quick flash of engine exhaust at end of burn, and a decrement to remaining ignitions.

https://youtu.be/SWxn9HGkFlY

[lamont-granquist]

Offhand I can't see the bug in the code. The principia node disappears, then it cuts the throttle, and that can only happen because ShouldTerminatePrincipia() goes true because dVleft has burned down, and that means Abort() should have been called which disables the node executor itself, and that should be the end of it. And it looks like you correctly hit "execute next node" instead of "execute all nodes" (looks like there might be a race condition where if dvLeft burns down before principia removes the maneuver node AND "execute ALL nodes" was pressed it might grab the current maneuver node thinking it is the next one--that is a possible bug, but you didn't hit that button).