The RN Wasp operated without doors because in the event of a ditching the flotation gear left the body of the aircraft below the surface and it made egress through the roof panel rather tricky I believe. Deflector panels were fitted to the forward hinges of the front doors to avoid a ninety knot gale in the cockpit in flight. It did make operating in the northern climes pretty chilly until they came up with heated gloves and socks which were particularly nice during the "Cod War".