The DoD and "the Congress made a decision that we would not see a near-peer threat within a number of years, and that decision, that judgment also proved to be optimistic," Lt. Gen. James Holmes, Air Force deputy chief of staff for strategic plans and requirements, told the US Senate Armed Services Committee.
"We've seen both Russia and China develop airplanes much faster than was anticipated," he added at a hearing held on March 8.
A total of 187 Raptors were produced between 1996 and 2011. The Pentagon is unlikely to order more F-22s, but the agency could well consider upgrading existing fifth-generation stealth tactical fighters.
Since the end of the Cold War, Russia has introduced the Yakovlev Yak-130 advanced jet trainer and light attack aircraft into service, as well as the Sukhoi Su-34 strike fighters and the Sukhoi Su-35S supermaneuverable multirole fighters.
Russian Aircraft Corporation MiG has also been reported as developing a fifth generation lightweight fighter jet.