Airworthiness Directives; The Boeing Company Airplanes
We propose to adopt a new airworthiness directive (AD) for all The Boeing Company Model 767-200, -300, and -300F series airplanes. This proposed AD was prompted by a finding that certain barrel nuts installed at the vertical fin may be subject to stress corrosion and cracking. This proposed AD would require either repetitive inspections of vertical fin barrel nuts for corrosion or a magnetic check to identify certain barrel nuts, and corrective actions if necessary. We are proposing this AD to detect and correct corroded and loose barrel nuts that attach the vertical fin to body section 48, which could result in reduced structural integrity of the vertical fin attachment joint, loss of the vertical fin, and consequent loss of controllability of the airplane.
Interpretation of the Flight Time Limitations
This action proposes to interpret our regulations to not apply to flight segments that are flown by a flightcrew consisting of only two pilots and no other flight crewmembers.
Airworthiness Directives; GE Aviation Czech s.r.o. Turboprop Engines
We propose to adopt a new airworthiness directive (AD) for certain serial number GE Aviation Czech s.r.o. M601E-11, M601E-11A, and M601F turboprop engines. This proposed AD was prompted by the determination that wear or cracking, and subsequent misalignment of the quill shaft of the engine and the power turbine (PT) shaft, may lead to rupture of the quill shaft, overspeed of the PT, and uncontained engine failure. This proposed AD would require inspection of the reduction gearbox and supporting cone. We are proposing this AD to prevent misalignment and rupture of the quill shaft, which could lead to overspeed of the PT, uncontained engine failure, and damage to the airplane.
Airworthiness Directives; ATR-GIE Avions de Transport Régional Airplanes
We propose to adopt a new airworthiness directive (AD) for all ATRGIE Avions de Transport R[eacute]gional Model ATR42 and ATR72 airplanes. This proposed AD was prompted by new occurrences of certain cracked main landing gear (MLG) rear hinge pins. This proposed AD would require identifying the serial number and part number of the MLG rear hinge pins, and replacement of pins or the MLG if necessary. We are proposing this AD to detect and correct cracked rear hinge pins, which could lead to MLG structural failure, possibly resulting in collapse of the MLG and consequent injury to the occupants of the airplane.