Wright Model C The Wright Model C " Speed Scout " was an early military aircraft produced in the United States and which first flew in 1912 . It was a development of the Model B but was specifically designed to offer the Aeronautical Division , U . S . Signal Corps a long - range scouting aircraft . It featured a more powerful engine over the Wright B , and an endurance of around four hours . Still a two - seater , it added a complete second set of controls , meaning that either crew member could operate the aircraft . On some , the lever controls were replaced with two wheels mounted on a single yoke . Aerodynamically , the small finlets ( " blinkers " in the Wrights ' terminology ) that had been used on the Model B ' s undercarriage were replaced by two vertical vanes attached to the forward end of the skids . The aircraft had a short service life , from 1912 to 1914 , because of a series of fatal crashes that destroyed six of the eight aircraft manufactured for the Army . Development . The increase in power was to meet Army specifications that the aircraft have a rate of climb of 200 feet per minute ( 1 m / s ) , a fuel capacity for a four - hour flight , and carry a weight of 450 pounds including crew . Its simplified twin - lever control system was confusing to operate and proved difficult for novice pilots to master , while the plane itself was tail heavy and unstable . Seven Model Cs were used by the Aeronautical Division : S . C . 10 - 14 , S . C . 16 , and S . C . 5 , a Burgess Model F rebuilt to Wright C standards . Five new Wright Scouts were delivered to the Aviation School at College Park , Maryland ; one to the provisional 1st Aero Squadron at Texas City , Texas ; and the last shipped to the Philippines . An eighth Aircraft ( S . C . 18 ) , a Burgess Model J delivered in January 1913 , was a Wright C built under license by the Burgess Company and Curtis . The aircraft were delivered between May 1912 and January 1913 and were subject to approval of ten flight tests by the Army before acceptance . The first delivered , to have been S . C . 10 , crashed during its climbing test on June 11 , 1912 , killing Wright Company pilot Arthur L . Welsh and Lt . Leighton W . Hazlehurst , and was replaced in October by another Wright C , itself destroyed in the last fatal crash on February 8 , 1914 . The crash involving Welsh was found by the Army ' s board of inquiry to have been pilot error by Welsh , who had intentionally placed the aircraft 45 degrees nose down prior to the test to build momentum . Deliveries of the plane continued , although the statement of one eyewitness led to speculation that the elevator had not responded to inputs to pull out of the dive . Operational history . The Model Cs quickly earned an unenviable reputation when six of the eight passing their acceptance flights crashed between July 8 , 1913 , and February 9 , 1914 , with all but one of the crashes involving fatalities . The fifth crash on November 24 , 1913 killed the Army ' s chief instructor and a new pilot . As a result , the Wright Company factory manager , Grover Loening , concluded that the Wright C was flawed by a design defect . Orville Wright disagreed , maintaining that pilot error was to blame , specifically unfamiliarity with the more powerful engine . He theorized that pilots stalled the aircraft by applying full power that in level flight made angle of attack critical . He proposed that full power be used only to climb and invented an angle - of - incidence indicator sensitive enough to warn a pilot that his climb or dive was too steep . He also completed work on an autopilot which he patented in October 1913 , and successfully demonstrated in December , but a gyroscope - operated autopilot patented by Lawrence Sperry proved more immediately practical and became standard . The final crash resulted in grounding of the two surviving Model C ' s on February 16 , 1914 . An Army board of investigation concluded that the elevator was " too weak " and that the Model C itself was " dynamically unsuited for flying , " despite testimony from Wright ' s chief instructor that poor maintenance played a key role in the fatalities . The Aeronautical Division hired Loening as an engineer to review the airworthiness of its airplanes , and use of S . C . s No . 16 ( which had a less powerful Model B engine ) and No . 5 ( a Burgess F rebuilt to Model C configuration ) , permanently discontinued on February 24 , 1914 , when on Loening ' s recommendation the Army de - commissioned all seven of its remaining " pusher " airplanes as a matter of policy .