AD FAA-2012-0637

We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes. This AD was prompted by a report of an inboard main landing gear (MLG) door assembly departure due to premature fatigue cracking in the inboard MLG door hinge fittings. This AD requires repetitive inspections for cracking of the inboard MLG door hinge fittings; and replacement or modification of cracked fittings. This AD also provides an option to remove the affected MLG door. We are issuing this AD to detect and correct fatigue cracking in the inboard MLG door hinge fittings, which could result in loss of the MLG door assembly from the airplane, and the MLG door assembly could impact the flight control surfaces and result in reduced controllability of the airplane.