Okay, so we know what caused the jammed pedals. What caused the thing to fall out of the sky
Pilot sitting X feet in front of the axis of rotation yawing at 148° per second shoulder harness unlocked, perhaps the 'g' forces are such that he is doubled over. My back of the envelope calculation comes up with a little over four 'g' assuming the point of rotation is half way between the two rotors. Front rotor is at station 93, rear 560. Issue mentioned by F-14 crew if the aircraft is in a flat spin (which is irrecoverable in the aircraft), not a posture you want for the recovery which is via ejection.
Lesson might be, fly with a locked harness, some carrier pilots can tell stories about face planting the instrument panel on an arrested landing..