In 1933, Wiley Post flew around the world alone, but the Gyropilot piloted the _Winnie Mae_ over most of the route. This relieved the fatigue of constant flying and allowed Wiley to keep a continual check on his maps. His successful use of the automatic pilot soon caused its adoption by most of the major airlines of the country. Thus, with the aid of the radio beam, better flight instruments, special octane gasoline, two-way radio, sound-proofing, wheel brakes, and adjustable pitch propellers, the airlines of America were fast emerging into a safe and comfortable means of travel. While the DC-2 was coming into prominence in the air transport field, Boeing engineers had gone on with their idea of a two-engined plane and had built an all-metal bomber for the Army. In building the two-engined, all-metal B-9, Boeing engineers learned how to build another plane with a more peaceful purpose. This ship was the famous Boeing 247-D commercial transport plane. The 247-D was an all-metal, low-wing monoplane, powered with two 550-horsepower Pratt & Whitney Wasp radial engines. It had a top speed of 200 miles per hour and a cruising speed of 180 miles per hour. It was America’s first three-mile-a-minute air transport plane. In designing the speedy 247-D, the Boeing did not forget the comfort of the passengers. The plane was fully heated and ventilated. Its seats were deeply upholstered and had reclining backs. There were broad windows at each chair. There were dome lights and individual reading lamps; and the plane was equipped with a tiny galley and a complete lavatory. Insulation kept the 247-D quiet and comfortable in any sort of weather. The 247-D carried ten passengers, a pilot, co-pilot, and stewardess, plus baggage and mail. It was first put into service by the United Air Lines in 1933, on their coast-to-coast route. Incidentally, it was United who had introduced to the airlines the third member of the air transport’s crew, the stewardess. The pretty young stewardesses were all trained nurses. They looked after air-sick passengers, served food en route, and looked after the comfort of the air travelers. [Illustration: BOEING 247 TRANSPORT POWERED WITH TWO 550-HP. PRATT & WHITNEY RADIAL ENGINES, THE 247 CRUISED AT 180 MILES PER HOUR. ITS TEN PASSENGERS RODE IN DEEPLY CUSHIONED SEATS WITH RECLINING BACKS. ITS WELL-VENTILATED, HEATED CABIN WAS SOUND-PROOFED TO DEADEN THE ROAR OF THE ENGINES, AND THE PASSENGERS RODE IN QUIET COMFORT.] LUXURY AIRLINERS AND SKYSLEEPERS MAKE AIR TRAVEL AN ACCEPTED FACT With the Boeing 247’s, United Air Lines in 1933 cut the coast-to-coast air trip to twenty-two hours. As DC-2’s and the fast two-engined Lockheed _Electras_ were speeding up air transport schedules on the airlines throughout the country, differences arose between the government and some air transport firms over mail contracts. The result was the cancellation in February, 1934, of all air mail contracts.