Airworthiness Directive · Amendment 39-11601 · Boeing Model 757 Series Airplanes
Boeing Model 757 Series Airplanes
Model 757 series airplanes, as listed in Boeing Service Bulletin 757-27A0127, Revision 1, dated September 2, 1999; certificated in any category.
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 757 series airplanes, that requires replacement of transmission assemblies for the trailing edge flaps with modified transmission assemblies. This amendment is prompted by reports of broken bolts that attach the transmission assemblies for the trailing edge flaps. The actions specified by this AD are intended to prevent damage to the flap system, adjacent system, or structural components; and excessive skew of the trailing edge flap; which could result in reduced controllability of the airplane.
To prevent damage to the flap system, adjacent system, or structural components; and excessive skew of the trailing edge flap; which could result in reduced controllability of the airplane; accomplish the following:
(a) Within 36 months after the effective date of this AD, replace the transmission assemblies for the trailing edge flaps with transmission assemblies modified in accordance with Boeing Service Bulletin 757-27A0127, Revision 1, dated September 2, 1999; or with new transmission assemblies that incorporate newly designed torque limiters; in accordance with the service bulletin.
Note 2: Replacements accomplished in accordance with Boeing Alert Service Bulletin 757-27A0127, dated September 10, 1998, are considered acceptable for compliance with paragraph (a) of this AD.
(b) As of the effective date of this AD, no person shall install on any airplane, a trailing edge flap transmission assembly, unless it has been modified in accordance with this AD, or, in the case of a new transmission assembly, unless it incorporates a newly designed torque limiter.
