NASA and SpaceX conducting a formal verification of SpaceX's emergency escape system. NASA astronauts Shannon Walker, in front, and Bob Behnken participated in the exercise to verify the crew can safely and quickly evacuate from the launch pad in the unlikely event of an emergency before liftoff of SpaceX's first crewed flight test, Demo-2. During the escape verification, Walker and Behnken pass through the water deluge system on the crew access tower. Photographed at Launch Complex 39A, Kennedy Space Center, Florida, USA, on 18th September 2019.