If he had had his head upright, when the roof was crushed it would've crushed his skull. He'd always worn a lap belt but never wore a shoulder harness until he heard this presentation at Embry Riddle, Daytona where he was a flight instructor.

He cut the switch like a pilot, which prevented the ignition of the Volkswagen front-end fuel tank (Hitler's revenge). Inverted, he did not release his seatbelt until he put his hand on the roof. If you are inverted, particularly at night, plan your egress before releasing the belt locating the proper handles.