It’s the most expensive fighter jet ever built. Yet the F22 Raptor has never seen a day of combat, and its future is clouded by a government safety investigation that grounded the jet. The fleet of 158 F22s has been sidelined since May 3, following more than a dozen incidents in which oxygen was cut off to pilots, making them woozy. The malfunction is suspected of contributing to at least one fatal accident. / This information could be read in www.freep.com.