'Workhorse' becomes first F-35 to achieve 1,000 flight hours

Published June 17, 2014
By Kenji Thuloweit
412th Test Wing Public Affairs

EDWARDS AIR FORCE BASE, Calif. -- AF-2, the second production F-35 Lightning II for the U.S. Air Force, became the first F-35 to reach 1,000 flight hours.

Paul Hattendorf, Lockheed Martin test pilot, was flying an Airframe Loads Envelope Expansion mission June 11 when the fighter reached the milestone.

"AF-2's nickname is 'Workhorse,'" said Randy Thompson, F-35 Integrated Test Force, Government Air Vehicle lead. "It continues to carry the Flight Sciences testing load executing its primary mission of loads envelope expansion. Every AF-2 flight-test hour moves the JSF enterprise closer to providing our warriors with the Air Force Initial Operational Capability and final System Development and Demonstration maneuvering envelopes.

Thompson added that data collected from all Flight Sciences aircraft help refine the airframe usage spectrum, which in turn allows for a more accurate fleet life determination.

The 412th Test Wing is home to 15 Lightning IIs. The Edwards F-35 ITF has nine F-35s assigned for developmental testing -- representing all three variants of the fifth-generation fighter: six F-35As, two F-35Bs and one F-35C.

Additionally, Edwards AFB's Operational Test units have six F-35As assigned.

"AF-2 is the 'Pull G's jet.' It was the first aircraft to hit plus-nine-G and negative-three-G and to roll at design-load factor. In addition, AF-2 is the first F-35A to intentionally fly in significant airframe buffet at all angles of attack," said Thompson.

Both AF-2 and AF-1 ferried to Edwards from the Lockheed Martin plant in Fort Worth, Texas, May 17, 2010.

Thompson said AF-2 has specific instrumentation and was calibrated for in-flight loads measurements prior to ferrying to Edwards. In addition, it is instrumented to execute airframe buffet testing; landing, braking and arresting hook testing; and ground and in-flight gun testing.

The Lightning II software has 24 million lines of code, which is continually being updated and improved. The ITF team, AF-2 and the rest of the Edwards F-35 test fleet, continues to get closer in getting the world's most advanced fighter into the hands of the warfighter.

"The entire F-35 Edwards ITF team and the 412 TW are pressing hard to complete testing required for the 2B fleet release (Marine Corp IOC mission systems software release and AF IOC maneuvering envelope release). As aircraft complete their slated 2B testing, the team moves ahead with testing required for the final SDD clearances. Post 2B testing milestones include putting the final SDD talons on the Lightning II with the first flight of the Small Diameter Bomb, first gun fire and continued external GBU-12 envelope expansion, as well as beginning to test the final SDD mission systems suite," concluded Thompson.

The planned date for Air Force Initial Operational Capability of its F-35As is August 2016.