No 92 or 93 IOT (1986) Graduation Parade had a Lightning flypast . It passed over the parade East to West then pulled a 270 and headed straight for CHOM. As the support sqn we were able to brace slightly by moving the left foot forward. Of course the gathered multitude had no idea what was going on behind them and the first they knew was went the aircraft went vertical right above their heads and disappeared out of sight. A number of seats needed to be dried out after the parade.