AD FAA-2010-0674

We are adopting a new airworthiness directive (AD) for the products listed above. This AD requires repetitive inspections for cracking in the body skin around the aft corners of the nose wheel well; for certain airplanes, repetitive inspections for cracking in the skin splice plate at the aft corners of the nose wheel well; and related investigative and corrective actions if necessary. This AD also requires repetitive post-modification inspections for cracking in the body skin and the skin splice plate; for certain airplanes, an inspection for steel cross-shaped doublers on the larger aluminum doublers; and corrective action if necessary. This AD also requires repetitive surface high frequency eddy current (HFEC) inspections of a certain bulkhead outer chord, skin splice plate, and outer chord radius filler for cracking; repetitive detailed inspections for cracking of the bulkhead frame web and body skin; and corrective actions if necessary. This AD provides for optional terminating action for certain repetitive inspections. This AD was prompted by reports of cracking of the fuselage skin and adjacent internal skin splice plate at the left and right nose wheel well aft corners, and the outer chord of the body station (BS) 400 bulkhead. We are issuing this AD to detect and correct cracking of the fuselage skin or splice plate, which, together with cracking of the bulkhead outer chord, could result in large skin cracks and subsequent in-flight rapid decompression of the airplane.