Airworthiness Directive · Amendment 39-15426 · Boeing Model 757-200, -200PF, and -200CB Series Airplanes
Boeing Model 757-200, -200PF, and -200CB Series Airplanes
This AD applies to Boeing Model 757-200, -200PF, and -200CB series airplanes, certificated in any category; as identified in Boeing Special Attention Service Bulletin 757-53-0077, Revision 1, dated August 6, 2007.
We are adopting a new airworthiness directive (AD) for certain Boeing Model 757-200, -200PF, and -200CB series airplanes. This AD requires doing an ultrasound inspection for disbonded tear straps not mechanically fastened to the skin, and related investigative and corrective actions, if necessary. This AD results from reports indicating that bonded skin panels may not have been correctly anodized in phosphoric acid before the tear strap doubler was bonded to the skin. We are issuing this AD to detect and correct a weak bond between the skin and tear strap. Such disbonding could reduce the ability of the skin to resist cracks and could adversely affect the structural integrity of the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
At the applicable initial compliance time in paragraph (f)(1) or (f)(2) of this AD, do an external ultrasound inspection for disbonded tear straps not mechanically fastened to the skin between stations 439 to 900, and 1180 to 1621, and between stringers 10 left and 10 right, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-53-0077, Revision 1, dated August 6, 2007.
(1) For airplanes with less than or equal to 21,000 total flight cycles: Before the accumulation of 24,000 total flight cycles, but no earlier than 18,000 total flight cycles.
(2) For airplanes with more than 21,000 total flight cycles: Within 3,000 flight cycles after the effective date of this AD.
If no disbonding is found during the ultrasound inspection required by paragraph (f) of this AD, repeat the inspection once before 36,000 total flight cycles, but no earlier than 30,000 total flight cycles.
If any disbonding is found during the ultrasound inspection required by paragraph (f) or (g) of this AD, do the applicable related investigative and corrective actions by accomplishing all the actions specified in the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-53-0077, Revision 1, dated August 6, 2007, at the applicable compliance time specified in paragraph 1.E., “Compliance,” of the service bulletin; except as provided by paragraph (i) of this AD.
(i) If any crack and/or corrosion is found during any inspection required by this AD, and Boeing Special Attention Service Bulletin 757-53-0077, Revision 1, dated August 6, 2007, specifies to contact Boeing for appropriate action: Before further flight, repair the crack and/or corrosion using a method approved in accordance with the procedures specified in paragraph (j) of this AD.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Aircraft
