Somatogravic Experience and Thoughts
The memories I have of military instrument training while sitting under the bag in the rear cockpit of my jet trainer all involve the sensation of sitting in a trash can while flying the aircraft. Success required conquering this illusion and allowing the information from the instruments to flow directly to the fingertips and stripping away the illusory body position information from my control inputs.
The first mention of the somatogravic illusion that I can recall was in an accident report from the late 1960s. An F-4 had cleaned up and accelerated to climb schedule below a low overcast while in afterburner and then pulled up into the overcast for the departure. The aircraft was then seen diving out of the overcast still in burner!
FWIW, With reference to the somatogravic illusion, night catapult shots were not unduly disorienting to me. After a bit of eye blurring 4+ g acceleration and shaking, the catapult letting go felt like a deceleration and the key tasks were setting the rotation attitude (not always trivial due to the variables involved) and verifying that you had flying speed.
There were other visual/body position illusions
encountered during my career as well that do not fall into the classic somatogravic illusion frame and will not be discussed here. If interested PM me.
The mental link that allows the mind to overpower one set of information with another will deteriorate with time. Simulators help reinforce the linkage, but perhaps we should not worry about perfect alignment of the calculated force direction applied by the simulator. Perhaps instead, the simulator should give a deliberate case of the “leans” or sitting in a bucket feeling so that the crews will reinforce their ability to override the somatogravic information they are bombarded with. Yes, it will make simulator sessions harder to do well, but I can about guarantee it will make you a better aviator.