F-35 Lightning II aircraft operating at 12 different locations worldwide surpassed the 50,000 flight hour mark this month.

The first flight hour was achieved by an F-35B aircraft, BF-01, June 1, 2008. The 25,000 flight hour milestone occurred in December 2014, six years and six months later. As a sign of program growth and maturity, the second 25,000 flight hours were reached only one year and two months later.

“The F-35 program continues to grow and accelerate as we complete additional flight testing and increase deliveries to our U.S. and partner warfighters,” said Lt. Gen. Christopher Bogdan, F-35 Joint Program Executive Officer. “The next 50,000 hours will be achieved much quicker as we double the size of the F-35 fleet worldwide in the next three years alone.”

Flight hours are divided into two main categories: Operational flying hours, flown by 155 jets delivered to six different nations, and System Development and Demonstration (SDD) flight test hours, flown by 18 aircraft assigned to the Integrated Test Forces at Edwards AFB, and NAS Pax River. Of the 50,000 hours, operational jets flew approximately 37,950 hours while SDD aircraft flew 12,050 hours. More than one third of the program’s flight hours were flown in 2015 alone. Among the three variants, approximately 26,000 hours were flown by the F-35A, 18,000 hours by the F-35B and 6,000 by the F-35C.

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