Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Boeing Model 777-200, -200ER, and -300 series airplanes. This proposed AD would require modification of the splice plate assemblies installed under the floor panels at the forward and aft edges of the cabin aisle. This proposed AD is prompted by reports of cracking of the aluminum splice plates under the floor panels in the cabin aisle. We are proposing this AD to prevent loss of the capability of the cabin floor and seat track structure to support the airplane interior inertia loads under emergency landing conditions. Loss of this support could lead to galley or seat separation from attached restraints, which could result in blocking of the emergency exits and consequent injury to passengers and crew.