WASHINGTON (Sputnik) - The F-35 fleet, the most expensive aircraft and military program in history, has reached 200,000 flight hours across global operations, Lockheed Martin announced in a press release as it is delivering the 400th F-35 jet.

“The F-35 air system is a key enabler of our National Defense Strategy and delivers the combat proven, advanced capabilities our warfighters and partners need to meet mission requirements", F-35 Joint Program Executive Officer Vice Adm. Mat Winter said in the release on Monday.

The 400th production aircraft is a US Air Force F-35A, to be delivered to Hill Air Force Base, Utah. The production run totals 283 F-35A, 87 F-35B and 30 F-35C planes. The 200,000 flight hours includes all development test jets, training, operational, US and international aircraft, the release said.

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Along with its staggering $1.5 trillion price tag, the F-35 program has been criticized by everyone from defence analysts to the current US president for a plethora of glitches and perceived design flaws that continue to plague the jet years after it began to be deployed in various branches of the US military in 2015.

In May, the Government Accountability Office calculated that between May and November of last year, only 27 per cent of the F-35 aircraft in the US military's arsenal were fully mission capable during that period, while nearly 30 per cent of the planes were unable to fly entirely due to parts shortages.

Earlier, the Project on Government Oversight, another US watchdog, said that the F-35 variant for the US Navy was nowhere near operational status, unprepared "to face current or future threats" and potentially dangerous for personnel operating the jets.

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