WASHINGTON—The Federal Aviation Administration (FAA) said on Friday it was requiring U.S. operators of 143 Boeing Co 737 Classic series airplanes to check for possible wire failures stemming from an investigation into an Indonesia crash in January. The 737 Classic is an older generation of planes more than two decades old. The FAA said the issue affected 1,041 737–300,–400 and–500 Classic series airplanes worldwide, but many are currently out of service, because of COVID-19 or other issues. The FAA is issuing an airworthiness directive for operators to verify that the flap synchro wire, which plays a role in the operation of the aircraft’s auto-throttle system, is securely connected to a safety sensor. The wire failure could go undetected by the auto-throttle computer on affected airplanes and pose a safety risk. The FAA is requiring some speedier checks than had been suggested by Boeing, which said late on Friday that it …