The Martin Mars prototype in take-off at an unknown location, possibly the Pacific off San Francisco. This photo was taken circa 1944, about two years after it had been converted from patrol bomber to transport aircraft, by the removal of its gun turrets, bomb bays, armored plating and other combat provisions. Instead, this transport version received additional cargo hatches and cargo loading equipment, as well as reinforced decking. Photo from: US Navy - National Naval Aviation Museum