Action
Final rule; request for comments.
Summary
We are adopting a new airworthiness directive (AD) for all The Boeing Company Model MD-90-30 airplanes. This AD requires a detailed inspection of the forward and aft surfaces on the left and right sides at the cant station 1520 bulkhead for any crack in the upper cap and (cap) doubler, webs and doublers, stiffeners, and the lower tee cap between longerons 3 through 11, and repairs if necessary. This AD was prompted by a report of cracking in various structures in the fuselage cant station 1520 bulkhead. We are issuing this AD to detect and correct cracking in the bulkhead, which could result in reduced structural integrity of the airplane.