F-35B test pilot applauds AEDC effort leading to successful first vertical flight

  • Published
  • By Philip Lorenz III
  • AEDC/PA
ARNOLD AIR FORCE BASE, Tenn. --  The recent first vertical landing of the Short Takeoff/Vertical Landing (STOVL) F-35B Lightning II Joint Strike Fighter at the Naval Air Station Patuxent River, Md., resonated with engineers at the U.S. Air Force's Arnold Engineering Development Center.

"This is a real exciting time for the F-35 program," said John Kelly, project manager with AEDC's 717th Test Squadron. "Pax River has completed the first vertical landing of the F-35 in-flight test and Edwards AFB will be ramping up their flight test operations soon."

Kelly pointed out that AEDC has had a direct effect on that flight and one that will provide confidence for upcoming flight tests.

"The AEDC community should view these events as personal achievements," he continued. "'Test Before Flight' is a pretty strong statement and not many people realize how much testing is involved prior to a flight. Recently, while testing an F135 Conventional Take Off and Landing (CTOL) variant, AEDC surpassed the 3,000 hour test mark during the early hours of the morning on March 24 while everyone else was probably still asleep."

The F135, which is the primary propulsion system for the F-35 Lightning II aircraft, has been tested in AEDC's C-1, J-2 and SL-3 test cells. More than 10,000 hours have been logged on models of the F-35 airframe and the F135 engine in AEDC's wind tunnels and engine test facilities.

"Aerodynamics, thrust and control are key components for the unique takeoff and landing capabilities of the F-35B," said Graham Tomlinson, BAE Systems test pilot for the first vertical landing flight. "At conventional speeds the lift comes from the wings. In the hover, the aircraft sits on engine thrust (core engine & lift fan combined), and vectored engine and lift fan thrusts are used to control the aircraft in all axes.

"Between the hover and conventional flight is a seamless blend of lift and thrust as the aircraft accelerates or decelerates."

Tomlinson emphasized the importance of ground testing conducted prior to his flight.

"The work at AEDC has helped to quantify basic airframe aerodynamics and engine responses so that our control models are updated using best possible data," he said. "That in itself is of critical importance to F-35B. But as any fighter pilot will tell you: 'Lift is a gift but thrust is a must.' This is especially true for the F-35B which is totally dependent for takeoff and landing on the thrust and reliability of the propulsive system."

Referring to the recent flight, Tomlinson said, "On March 18, we had the proof of the pudding, with a faultless STOVL mission at NAS Patuxent River starting with a short takeoff at 80 knots (which will be a typical launch speed from a USN L-Class ship) and ending with a vertical landing. The aircraft was as solid as a rock and the cockpit workload was refreshingly low, a generational leap better than legacy STOVL aircraft."

Looking toward the future, he added, "Generations of U.S. Marine Corps and partner nation pilots will thank AEDC for assuring us the engine reliability we need to come home safely to small ships and austere operating bases."

The F-35B will provide a combination of capabilities never before available: stealth, supersonic speed and STOVL basing flexibility.

F-35 Lightning IIs will replace a wide range of existing aircraft, including A-10s, F-16s, F/A-18s and AV-8B Harriers. The STOVL version of the F-35 will be used by the U.S. Marines and the British Royal Navy.

The F-35 program is the world's largest military project, involving 11 countries and employing about 20,000 people worldwide.