Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Boeing Model 757-200, -200CB, and -300 series airplanes. This proposed AD would require repetitive inspections for cracks of the intercostal tee clips and attachment fasteners at the number 3 and number 4 doorstops of the passenger door cutouts, or repetitive inspections for cracks of the intercostal tee clips; and related investigative/ corrective actions if necessary. This proposed AD also provides an optional terminating action for the repetitive inspections. This proposed AD results from reports of cracked intercostal tee clips at the number 3 and number 4 doorstops of the passenger door cutouts. We are proposing this AD to detect and correct cracking of the tee clips, which could result in additional stress on the adjacent tee clips, surrounding intercostals, edge frame, door structure and doorstops. This additional stress could cause further cracking or breaking of the tee clips, which could resultin failure of the door to seal and consequent rapid decompression of the airplane.