Lockheed Martin has demonstrated the maturity of its F-35 Lightning II joint strike fighter (JSF) programme through a series of flight tests in the US.
Designated AF-1, the conventional takeoff and landing (CTOL) F-35A fighter successfully accomplished its 400th flight during a successful GBU-31 joint direct attack munition (JDAM) aircraft separation test at Edwards Air Force Base, California.
The test represented the GBU-31 Mark-84 separation demonstration from the F-35, whose previous GBU-31 separations were with the Bomb Live Unit (BLU)-109 bomb body.
Earlier this month, the F-35B short take-off and vertical landing (STOVL) aircraft, designated BF-1 and BF-4, completed 'Mode 4' formation testing, as required for Block 2B software capability.
Lockheed Martin F-35 Test and Verification vice-president JD McFarlan said: "In Mode 4 operations, the STOVL Propulsion System is engaged, the lift fan, roll post nozzle and three-bearing-swivel nozzle are operating, and all propulsion system doors and inlets are open.
"Flight testing validated the F-35B STOVL variant's ability to operate well in this configuration during formation flight, which supports operations around the ship; a key milestone for the F-35B path to IOC."
Another F-35B aircraft, BF-3, completed the 2B software fleet release weapon separation requirements for the variant with two successful AIM-120 advanced medium range air-to-air missile separation flights over the Atlantic Test Range.
McFarlan added: "2B software fleet release is critical to the warfighter because it delivers the first combat capability to our most dominant fifth generation platform. Weapons employment is one the most critical combat capabilities.
"This culminates years of dedicated work that proves safe separation in 2B configurations and provides this capability and confidence to our customers."
In addition to testing milestones, the overall F-35 fleet surpassed 19,500 flight hours, with more than 8,000 hours in system development and demonstration (SDD) aircraft.
Under development by Lockheed, the F-35 JSF is a fifth-generation multirole fighter designed to conduct ground attack, reconnaissance and air defence missions with stealth capability.
Image: Two F-35B aircraft fly together in Mode 4 formation near NAS Patuxent River, Maryland, US. Photo: Lockheed Martin photo courtesy of Andy Wolfe.