Director Bill Wellman hired the newly-licensed Mary to double for Sally Eilers in Central Airport in a chute jump from a wing. One trick thought up by aerial stunter J. P. Pate almost ended Mary’s life. Pate planned a parachute jump in which he and Mary would exchange parachutes after leaving the plane at 10,000 feet. They were joined by a heavy rope hooked to leather belts around their waists and they had another rope arrangement which would pull the rings and open their chutes simultaneously. Since each chute was 30 feet in diameter, there was that much distance between them. The two pulled until their arms were sore and the rope had cut through their leather gloves. No matter how hard they tried to reach each other, Mary realized it was impossible. She released the hook on her belt and landed safely. Pate received a broken shoulder.
Mary was one of the first Women Air Force Service Pilots (WAPs) to report for duty at Hondo Army Airfield in 1943.