Just to clarify some points of confusion that may have crept in here, the critical formula in the transitional speed range with the metal wing involved sideslip, angle of attack and airspeed. If you could keep any one of these to zero, the other 2 would not bite; this was the key to John Farley's amazing flights along a line in the critical speed range while yawing continuously - he kept the AoA at zero. In normal use, it was more useful to keep sideslip, as betrayed by lateral G, to a low value. Hence the RPS, backed up by the HUD sideslip ball, and the vane if the electrical stuff didn't work. Many a student Harrier pilot will have heard the instructor's cries of "Vane, vane, VANE!" during a dodgy transition (or a low speed fight).
Intake momentum drag is another interesting subject covered at length here some time ago. It relates to high power settings and will indeed produce unwanted pitch or yaw, but not roll.
Operation of the RPS was very common, and not a matter for extreme reaction. On a gusty day, you could get both pedals going in turn so you just had to do your best to mean out the sideslip while reducing AoA and IAS.
By the way, while the aircraft vane was a very simple device, the only place it became complicated was in the simulator. With no real airflow to drive it, it had to be motorised to comply with the simulated flight conditions.
Last edited by noprobs; 17th Aug 2008 at 15:54.