Summary
The FAA proposes to supersede Airworthiness Directive (AD) 2021-09-06, which applies to all The Boeing Company Model 737-600, - 700, -700C, -800, -900, and -900ER series airplanes. AD 2021-09-06 requires repetitive inspections for cracking of the left- and right- hand side outboard chords of certain frame fittings and failsafe straps at a certain station around eight fasteners, and repair if any cracking is found. Since the FAA issued AD 2021-09-06, additional reports of cracking in the area were received and it was determined that additional inspections are needed to address the unsafe condition. This proposed AD would require repetitive detailed and ultrasonic inspections for cracking of the left-and right-hand sides of certain frame fittings and failsafe straps, and repair if any cracking is found. The FAA is proposing this AD to address the unsafe condition on these products.