Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Boeing Model 757 series airplanes. This proposed AD would require repetitive inspections for corrosion and cracking of the midspar fittings in the nacelle struts, and corrective actions if necessary. This action also provides an optional terminating action for the repetitive inspections. This proposed AD is prompted by reports of corrosion and cracking on midspar fittings on the nacelle struts of several Boeing Model 757 series airplanes. We are proposing this AD to detect and correct cracking in the midspar fittings of the nacelle struts, consequent reduced structural integrity of the struts, and possible separation of an engine and strut from the airplane.