Airworthiness Directives; The Boeing Company Model 737-100 and -200 Series Airplanes

摘要

We propose to adopt a new airworthiness directive (AD) for certain Model 737-100 and -200 series airplanes. This proposed AD would require repetitive inspections for cracking and damaged fasteners of certain fuselage frames and stub beams, and corrective actions if necessary. For certain airplanes, this proposed AD would also require repetitive inspections for cracking of the inboard chord fastener hole of the frame at body station 639, stringer S-16, and corrective actions if necessary. For certain airplanes, this proposed AD would also require an inspection to determine the edge margin of the lower chord. For airplanes with a certain short edge margin, this proposed AD requires repetitive inspections for cracking, and corrective actions if necessary; replacing the lower chord terminates the repetitive inspections. This proposed AD requires an eventual preventive modification. For certain airplanes, doing the modification or a repair would terminate the repetitive inspections for the repaired or modified frame only. For airplanes on which the modification or repair is done at certain body stations, this proposed AD would require repetitive inspections for cracking of certain frame