Washington (CNN) -- The problem-plagued F-22 Raptor took part in its first combat mission Monday night, hitting ISIS targets in Syria. The price tag for those jets, which were in development for decades, is a staggering $412 million each -- triple its expected cost, according to the Government Accountability Office (GAO). Originally designed and built to replace other fighter and ground attack aircraft in the U.S. military's arsenal, the radar-evading F-22 is an evolutionary dead end. The Air Force acquired only 188 of them from aerospace maker Lockheed and doesn't plan to have any more produced. Even though they formally came into service in 2005, the F-22 had been grounded repeatedly because of what were indeterminate causes that resulted in pilots losing consciousness in the air.
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The F-22 flew its first combat mission against ISIS
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The government estimates that each plane costs $412 million
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The fighter jet has been plagued by mechanical problems and cost overruns
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