The second short takeoff/vertical landing (STOVL) variant of the F-35B Lightning II accomplished its first flight Feb. 25 at Lockheed Martin’s Fort Worth, Texas, facility.

The aircraft, designated BF-2, joins a conventional takeoff and landing (CTOL) F-35A and the first flying STOVL F-35B, which have logged 84 total flights, Lockheed Martin said.

BF-2 is scheduled to deploy to Naval Air Station Patuxent River, Md., later this year. It will remain in Fort Worth for the next several months to conduct a series of ground-test events, instrumentation calibration, powered hover-pit testing and airworthiness flights, including STOVL-mode operation. Initial flights will be in conventional mode.