Summary
We propose to adopt a new airworthiness directive (AD) for all The Boeing Company Model 737-600, -700, -700C, -800, and -900 series airplanes. This proposed AD was prompted by reports of paint deterioration on the surface of the main landing gear (MLG) and the early onset of corrosion in the trunnion bore of the MLG outer cylinder. This proposed AD would require identifying affected parts, repetitive external surface detailed inspection for damage of affected parts, and related investigative and corrective actions if necessary. For certain airplanes, this AD also would require a detailed inspection and bushing replacement of the trunnion bore, and related investigative and corrective action if necessary. We are proposing this AD to prevent stress corrosion cracking of the external surfaces of the MLG, which could result in a fracture of the MLG and consequent MLG collapse.