Boeing | ||||||||||||||||||||
B247 # |
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Photo: Robert Deering 1977 Smithsonian National Air and Space Museum Washington, DC |
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The Boeing Model 247 was an early United States airliner, considered the first such aircraft to fully incorporate advances such as all-metal (anodized aluminum) semi-monocoque construction, a fully cantilevered wing and retractable landing gear. Other advanced features included control surface trim tabs, an autopilot and deicing boots for the wings and tailplane. "Ordered off the drawing board", the 247 first flew on February 8, 1933, and entered service later that year. Subsequently, development in airliner design saw engines and airframes becoming larger, and four-engine designs emerged, but no significant changes to this basic formula appeared until cabin pressurization and high altitude flight were introduced in the early 1940s with the first pressurized airliner, the 307 Stratoliner. As the 247 emerged from its test and development phase, the company further showcased its capabilities by entering a long-distance air race in 1934, the MacRobertson Race from England to Australia. During the 1930s, aircraft designs were often proven in air races and other aerial contests. A modified 247D was entered, flown by Col.Roscoe Turner and Clyde Pangborn. The 247, race number "57," was essentially a production model but all airliner furnishings were deleted to accommodate additional fuselage fuel tanks (eight in total). The MacRobertson Race attracted aircraft entries from all over the globe including prototypes as well as established production types with the grueling course considered an excellent proving ground as well as an opportunity to gain worldwide attention. Turner and Pangborn came in second place in the transport section (and third overall), behind the Boeing 247's eventual rival, the new Douglas DC-2. Winner of the 1934 US Collier Trophy for excellence in aviation design, the first 247 production orders were earmarked for William Boeing's airline Boeing Air Transport. The 247 was capable of crossing the United States from east to west eight hours faster than its predecessors, such as the Ford Trimotor and Curtiss Condor. Entering service on May 22, 1933, a Boeing Air Transport 247 set a cross-country record pace of 19½ hours on its San Francisco to New York inaugural flight. For the first time airline passengers could fly across the country without changing planes or stopping overnight. Due to the initial demand from U.S. air carriers, Boeing sold the first 60 247s, an unprecedented $3.5 million order to its affiliated airline, Boeing Air Transport (part of the United Aircraft and Transport Corporation, UATC), at a unit price of $65,000. TWA (Transcontinental & Western Air) also ordered the 247 but UATC declined the order, which resulted in TWA President Jack Frye setting out the requirements for a new airliner and funding Don Douglas to design and build the Douglas DC-1 prototype. Douglas eventually developed the design into the historic and enormously successful DC-3 line. Although the Boeing design had been the first to enter series production, the 247 proved to have some serious design deficiencies. Air carriers considered its limited capacity a drawback since it only carried 10 passengers, in five rows with a seat on each side of the aisle, as well as a flight attendant. Compared to the more capacious DC-2 and later DC-3, the passenger count was too few to make it a commercially viable airliner. Another feature influencing passenger comfort was that the 247's main wing spar ran through the cabin, so persons moving through the cabin had to step over it. The Lockheed Model 10 Electra had a similar configuration and while it was a more compact design, the Electra managed to carry the same number of passengers at a slightly better overall performance, and more importantly, at a lower cost-per-mile. Seventy-five 247s were built; by contrast, Douglas collected 800 civil orders for DC-3s before the Pearl Harbor attack, and produced over 10,000 DC-3s, including wartime production of C-47; while the rival Lockheed Electra "family" was eventually to reach over 3,000 in its various civilian and military variants. Boeing Air Transport bought 60 examples, United Aircraft Corp. (10), four went to Deutsche Luft Hansa, and one a private owner in China. While the industry primarily standardized on Boeing's competitors, many of United's aircraft were later purchased by Western Air Express at "bargain basement prices". The 247 remained in airline service until World War II, when several were converted into C-73 transports and trainers. No. 121 Squadron, Royal Canadian Air Force (RCAF) operated seven Model 247Ds as medium transports during the early part of the war. Some 247s were still flying in the late 1960s, converted either into cargo transports or personal business aircraft. |
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