PSG inappropriately cuts throttle during guidance #2034
Description
MechJeb Version
MechJeb2-2.15.1.0-1493
KSP Version
1.12.5.3190 LinuxPlayer
Description
PSG momentarily cuts throttle during ascent under some conditions.
Replication Case
Here is an example that consistently replicates this issue in KCT simulation. Proper Ascent Guidance settings can be seen in the second picture, but for ease of use:
Set last stage to 0, fixed burn stages to 0,1, no unguided stage, coast before stage 0 for min 0 max 450. Booster pitch start 50m/s, rate 0.5 deg/s, Q-alpha limit 2000 Pa-rad. FPA 0, Burnout alt 300km, orbit due east from a roughly equatorial launchpad.
First picture is from using PVG in MechJeb2-2.15.1.0-1485 as proof that it works. All the rest are from MechJeb2-2.15.1.0-1493
Second picture is before ignition but after autopilot engage. Third picture is beginning of coast; hasn't staged yet because of fairings but so far nominal performance. Fourth picture is at final stage ignition. Fifth shows everything apparently going fine, seconds before disaster. Sixth picture is caught in the act; you can actually see the throttle UI element drop to zero momentarily before returning, but my fingers weren't quick enough for that to be in the picture. However, note PSG still thinks it's burning as if everything is fine.
KSP.log
Other files
Craft
persistent.sfs
My custom launch.cfg that will allow you to choose Zanzibar as a launch site (used in the pictures above)
Other mods
RP-1 Express Install
Principia (Laplace release)
Janitor's Closet
Waypoint Manager
Docking Port Alignment Indicator