Federal safety officials have mandated inspections of cockpit seats on Boeing 787 Dreamliners following an alarming incident where one of the jets suddenly dove when the captain's seat unexpectedly lurched forward, disengaging the autopilot. The Federal Aviation Administration (FAA) will require operators of 787s to inspect both pilot seats for missing or cracked caps that cover a crucial switch controlling seat movement. The inspection order, set to be published on Wednesday, affects 158 planes registered in the United States.