AD FAA-2013-0694

We are superseding Airworthiness Directive (AD) 2002-10-11, which applied to certain The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. AD 2002-10-11 required repetitive inspections for cracking and corrosion of the aft pressure bulkhead, and corrective actions if necessary; and, for certain airplanes, enlargement of frame chord drain holes, and repetitive inspections of the frame chord drain path for debris, and corrective actions if necessary. This new AD specifies a drain path inspection for all airplanes. For certain airplanes, this new AD reduces the repetitive inspection interval; and adds repetitive inspections of the frame chord drain path for obstructions and debris, and corrective actions if necessary. This AD was prompted by three reports of severe corrosion in the area affected by AD 2002-10-11. We are issuing this AD to detect and correct corrosion or cracking of the aft pressure bulkhead, which could result in loss of the aft pressure bulkhead web and stiffeners, and consequent rapid decompression of the airplane.