Summary
The FAA proposes to adopt a new airworthiness directive (AD) for all Boeing Model 777-200, -200ER, and -300 series airplanes. This proposed AD would require inspection of the outer cylinder of the main landing gear (MLG) to determine the serial number; an ultrasonic inspection of the outer cylinder of the MLG for cracks if necessary; and applicable specified and corrective actions if necessary. This proposed AD is prompted by reports indicating that two outer cylinders were found fractured in the weld area. We are proposing this AD to detect and correct cracks or defects that could result in a fracture of the outer cylinder of the MLG, which could lead to collapse of the MLG during landing.