The tailslide was unintentional. The goal for that maneuver had been to demonstrate the minimum entry speed for a loop and included a build-up to that maneuver (13:41 in the video). When the airplane stalled on the upline I knew I was in trouble, the plan had been to use a hammerhead to recover...it sort of worked. Important note: a T-18 has no uplock on the flaps, so if the airplane goes to negative G there is the risk that the flaps will deploy uncommanded and damage the airplane. This the las