NAVAL AIR STATION WHIDBEY ISLAND, Wash. — The pilot sat strapped to a chair, held in place as if he were in the backseat of a helicopter. Beside him, on a mock wall, was a window. The window was closed.

The pilot wore opaque goggles. He could not see the window or anything else. The chair was attached to a rotating stand in the chest-deep water of a swimming pool. A petty officer spun a large wheel, flipping the chair backward with a gentle whoosh. The pilot was now underwater, upside down.

Another exercise in the test had begun.

The pilot — feet near the surface, head near the bottom, sightless — was to disconnect himself from the buckled straps, wiggle free, open the window and pull himself through and out, a series of movements intended to simulate what he might need to do in an aircraft that had struck the sea at night.

Every four years, the Navy requires its pilots and those who fly with them to renew their skills in escaping from downed aircraft or surviving an ejection and parachute descent into water. The refresher class, depending on where each student is based, is held in one of several schools like this one, the Aviation Survival Training Center on this Navy base in coastal Washington State.