WASHINGTON, Jan 18 (Reuters) - The Federal Aviation Administration (FAA) said on Tuesday it was withdrawing proposed conditions that could have allowed delivery company FedEx Corp (FDX.N) to install a laser-based missile-defense on Airbus A321-200 airplanes. The FAA said Tuesday it "has determined that further internal study is necessary." The FAA said to avoid confusion "a comment period on a proposal that the agency is not moving forward at this time, the FAA is withdrawing the notice." FedEx did not comment Tuesday and the FAA declined comment beyond the withdrawal. The FAA had said on Friday it was proposing conditions and opening the proposal for public comment. In October, 2019, FedEx applied for approval to use a feature that emits infrared laser energy outside the aircraft as a countermeasure against heat-seeking missiles, the FAA disclosed Friday. For decades, the airline industry and several governments have been grappling with the threat to airliners from shoulder-fired missiles known as Man-Portable Air Defense Systems, or MANPADs. Some use infrared systems to target an aircraft"s engines. "The FedEx missile-defense system directs infrared laser energy toward an incoming missile, in an effort to interrupt the missile’s tracking of the aircraft’s heat," the FAA document said. According to the U.S. State Department, more than 40 civil airplanes have been hit by MANPADs since the 1970s. In November 2002, two missiles narrowly missed an Arkia Israeli Airlines Boeing 757 passenger jet on take-off from Mombasa airport, and efforts to combat the threat accelerated. In 2003, an Airbus A300 freighter flown by DHL was damaged by MANPADs and forced to make an emergency landing in Baghdad. In 2007 and 2008, FedEx took part in a U.S. government trial of anti-missile technology for civil planes by installing Northrop Grumman"s (NOC.N) Guardian countermeasures system on some commercial cargo flights while BAE Systems (BAES.L) said it had installed its JetEye system on an American Airlines airplane.