Summary
The FAA proposes to supersede an existing airworthiness directive (AD) that applies to all Boeing Model 737-200C series airplanes. The existing AD currently requires a one-time external detailed inspection for cracking of the fuselage skin in the lower lobe cargo compartment; repetitive internal detailed inspections for cracking of the frames in the lower lobe cargo compartment; repair of cracked parts; and terminating action for the repetitive internal detailed inspections. This proposed AD restates the requirements of the existing AD and adds a requirement to perform repetitive detailed inspections of the body station (BS) 360 and BS 500 fuselage frames, after accomplishing the terminating action, and repair if necessary. This proposed AD results from multiple reports that the existing AD is not fully effective in preventing cracks in the BS 360 and BS 500 fuselage frames. We are proposing this AD to detect and correct cracking of the fuselage frames from BS 360 to BS 500B,which, if not detected, could lead to loss of the cargo door during flight and consequent rapid decompression of the airplane.