Pardon me for asking so many questions. I am not doubting your assertions, I just don't fully understand them. I can be rather dense when it comes to orbital mechanics.
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Originally Posted by Lieste
Well, for any given orbit there are prescribed combinations of velocity and altitude.
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Got it, I'm with you so far. I was under the impression most shuttle ascent profiles were pretty similar. I do get the feeling SSM more or less "rides the rails" and just tries its best to match historical ascent profiles for the given mission selected.
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SSM2007 will often not acheive the nominal values during ascent, which is fine, as there should be plenty of delta_v remaining for an OMS-1 burn to recover all but a very bad insertion.However, the 'game' assumes a nominal orbit, and only adds the nominal delta_v. The OPS 105/OPS 202 pages show the supposed 'nominal' profile and performs burns using these nominal values, but the shuttle itself can follow completely different profiles throughout the mission (including orbiting at < 75% the correct energy). An example would be an insertion with an apogee of <60nm, while OPS 105 is indicating perigee of 75nm and apogee of 107nm.
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On any particular mission, or does it happen on every ascent? How do you know the OPS 105/202 values are erroneous? I'm assuming by looking at the MCC screen?
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The ADI error can be seen simply by rotating to 0,0,0 then setting the reference attitude using the panel switch. Return to the nominal attitude, and then set the ADI mode to 'Ref'. You *should* see a yaw angle of 90 degrees, and level 'ball'. (which incidently is the correct attitude for INRTL mode, the white-bar forwards should be obtained by programming the reference attitude, not by altering the inertial frame of reference.) As far as I am aware, you will still see a value of '60' on the ball.
If you are currently upside down, and facing the opposite direction to that required (as for example after the deorbit burn) then it should be possible to re-orient by either yawing 180 degrees then rolling, or by pitching 180. However attempting to yaw will result in wild meanderings. (Yaw pitch and roll do work correctly when facing 'forwards' to the reset INRTL ball though).
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I'll try the ADI stuff another time on just focus on understanding the orbital glitches now.
PD