AVIATOR HUGHES XF-11
Completing the Hughes XF-11 airplane in 3 months proved to be one of the biggest challenges for the Aero Telemetry team. Joe Bok and his team had to design a custom set of landing gear, fabricate an ultra-strong airframe, coordinate a complex flight control system, test counter-rotating engines, and integrate all of these systems seamlessly to overcome the aerodynamic stresses of high speed and heavy payload.
Photo courtesy of Miramax Films
HISTORY OF THE HUGHES XF-11
Howard Hughes XF-11 was a prototype reconnaissance aircraft made for the US military. On July 7,1946 Hughes himself piloted the plane on its maiden flight. After being airborne for over two hours, the starboard propellor began to fail and made the XF-11 pull violently to the right. Hughes did all he could to save the crippled plane but, unfortunately ended up crashing and taking out three homes in the process. The plane was destroyed and the crash nearly killed Howard Hughes.
THE HUGHES XF-11 DESIGN & BUILD
The Aviator XF-11 replica designed and built by Aero Telemetry had a wingspan of 25 ft. Because of its size and weight the model performed exactly as a full-size aircraft would and provided the cameras with spectacular, stunning, and realistic flight sequences.
To counteract any unexpected flight behavior or tendency for The Aviator XF-11 to yaw (move right or left) because of gyroscopic precession, Joe Bok designed the airplane to have each of the engines and propellers turn opposite each other to cancel out the energy created by the rotating propellers.
The original XF-11, designed by Howard Hughes and his talented engineering staff, incorporated several ingenious designs to allow the airplane to exceed it's original mission profile. Like Howard Hughes and his team, Joe and his engineering staff incorporated several ingenious designs into their version of the XF-11.
The aerodynamic profile of the wing, engine thrust-lines, CG location, main airfoil angle of attack, incidence angles (between wing and horizontal stabilizer), counter-rotating propellers, and vertical stabilizer offset angles were just a few of the critical design criteria addressed and implemented correctly by the Aero Telemetry engineering design team. All these specific details contributed directly to the success and margin of safety exemplified in all the flights of the Aero Telemetry XF-11.
XF-11 LANDING GEAR
Custom hydraulic landing gear were designed and fabricated for the 1/4 scale XF-11. Due to the compressed schedule, the gear had to designed, tested, and installed during an incredibly short time-frame. There was no room for errors.
XF-11 ENGINE TESTING
The XF-11 was powered by two twin cylinder air-cooled 2-stroke engines modified to 273cc. The starboard engine was additionally modified to turn in the opposite direction than the port engine. This gave the model additional stability about the Yaw axis. Hours of testing each engine by the Aero Telemetry team helped make sure the engines would be operating at maximum power output during the flights. The engines used fixed-pitch, counter-rotating propellers provided by the Tennessee Propeller Company.