The first Lockheed Martin [LMT] F-35 Lightning II fighter has finished all initial tests at Edwards AFB, Calif., and is now ready to begin its flight test program, the company said last week.

During the three-week deployment at Edwards, most of the F-35’s activity centered on a set of tests that validated the aircraft’s ability to shut down and restart its engine in flight. During the tests–conducted to ensure that the aircraft can regain power and be flown safely in the event of an unanticipated engine flameout–the Pratt & Whitney [UTX] F135 turbofan repeatedly restarted on command, according to an Oct. 23 Lockheed Martin press statement.

The initial data and pilot-reported results have been “very favorable,” the company reported.

The F-35 involved in the testing is a conventional takeoff and landing variant that has completed 63 flights. Three F-35 variants derived from a common design will replace at least 13 types of aircraft for 11 nations initially.

By the end of next year, all 19 F-35 test aircraft will be complete, and initial Operational Test & Evaluation is expected to begin in the 2013-2014 time frame.

Lockheed Martin is developing the F-35 with subcontractors Northrop Grumman [NOC] and BAE Systems. Two interchangeable engines are under development: the Pratt & Whitney F135 and the General Electric [GE]-Rolls-Royce Fighter Engine Team F136.