AD 92-17-10

92-17-10 BOEING: Amendment 39-8339. Docket No. 92-NM-30-AD. Supersedes AD 91-24-10, Amendment 39-8096.

Applicability: Model 757 series airplanes; line positions 001 through 408, inclusive; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent uncommanded spoiler deployments caused by failed spoiler Power Control Actuators (PCA), accomplish the following:

(a) Within 10 days after December 2, 1991 (the effective date of AD 91-24-10, amendment 39-8096), incorporate the following procedures into the Limitations Section of the FAA-approved Airplane Flight Manual (AFM). This may be accomplished by inserting a copy of this AD into the AFM.

"If, upon selection of flap 25 or 30, the SPOILERS EICAS message is observed, uncommanded airplane roll is encountered, or sustained control wheel displacement is required, immediately retract flaps to 20 and use flaps 20 and Vref 20 for landing. Select the ground proximity flap override switch to override."

(b) If, upon selection of flap 25 or 30, the SPOILERS EICAS message is observed, the SPOILERS caution light illuminates, or uncommanded airplane roll is encountered, prior to further flight, determine if a spoiler PCA fault ball is displayed on any of the spoiler control modules. If a spoiler fault ball is displayed, prior to further flight, identify the failed spoiler PCA pair and replace both spoiler PCA's, unless the direction of the roll upset is known, in which case only the spoiler PCA in the wing of the roll direction must be replaced. Any spoiler PCA that has been removed in accordance with this paragraph must not be installed on any airplane until the spoiler PCA is modified in accordance with Boeing Alert Service Bulletin 757-27A0105, dated December 5, 1991.

(c) Within 24 months after the effective date of this AD, replace the PCA's on all outboard spoilers (positions 1, 2, 3, 10, 11, and 12), in accordance with Boeing Alert Service Bulletin 757-27A0105, dated December 5, 1991.

(d) Within 48 months after the effective date of this AD, replace the PCA's on all inboard spoilers (positions 4, 5, 6, 7, 8, and 9), in accordance with Boeing Alert Service Bulletin 757-27A0105, dated December 5, 1991.

(e) Replacement of all spoiler PCA's, as required by paragraphs (c) and (d) of this AD, constitutes terminating action for the requirements of this AD for that airplane. Once replacement is accomplished, the operating limitations required by paragraphs (a) and (b) of this AD may be removed.

(f) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send itto the Manager, Seattle ACO.

NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.

(g) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished.

(h) The replacement shall be done in accordance with Boeing Alert Service Bulletin 757-27A0105, dated December 5, 1991. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street NW., 7th Floor, Suite 700, Washington, DC.

(i) This amendment becomes effective onSeptember 28, 1992.