Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Boeing Model 737-300, -400, and -500 series airplanes. This proposed AD would require repetitive inspections for cracking of the crown area of the fuselage skin, and corrective actions, if necessary. This proposed AD is prompted by a 737 fuselage structure test and fatigue analysis that indicate fuselage skin cracking could occur between 21,000 and 42,000 total flight cycles. We are proposing this AD to detect and correct fatigue cracking of the fuselage skin, which could cause the fuselage skin to fracture and fail, and could result in rapid decompression of the airplane.