National Geographic : 1940 Dec
Photograph from North American Aviation Coming Head-on, This Medium Bomber Shows How Highly Streamlined Are Modern Planes With wheels retracted and every possible protuberance removed, it offers minimum air resistance and also forms asmall target. Photograph courtesy ofthe Glenn L.Martin Co. Long-range Navy Patrol Bombers Like These Guard the Sea Approaches toNorth America The Martin flying boat is taxiing on the "step," a break in the hull bottom which reduces water resistance and makesthe take-off easier. Wing floats areretractable.