93-16-07 BRITISH AEROSPACE: Amendment 39-8664. Docket 93-NM-31-AD.
Applicability: Model BAe 146 series airplanes; on which Fairey Hydraulics airbrake servo-valve assembly, part number 3799H1, has been installed; certificated in any category.
Compliance: Required as indicated, unless accomplished previously.
To prevent malfunction of the airbrake; this could result in uncommanded airbrake extension or retraction, which, subsequently, could adversely affect airplane performance, accomplish the following:
(a) Within 90 days after the effective date of this AD, perform a visual inspection to determine whether Abex servo-valve, part number 72189, has been installed and to identify the serial number on the Abex servo-valve, in accordance with British Aerospace BAe 146 Inspection Service Bulletin S.B. 27-133, dated January 31, 1992.
(1) If an Abex servo-valve, part number 72189, has been installed, having a serial number listed in Table I of the service bulletin: Prior to further flight, accomplish the requirements of paragraphs (a)(1)(i) and (a)(1)(ii) of this AD.
(i) Remove the existing servo-valve assembly in accordance with the service bulletin.
(ii) Perform a visual inspection to detect metallic debris in the filter mesh in the servo-valve in accordance with the service bulletin. If any debris is detected, replace the currently installed airbrake actuator with a new or serviceable airbrake actuator, and install a new or serviceable servo-valve assembly in accordance with the service bulletin.
(2) If an Abex servo-valve has been installed and has a serial number listed in Table 2 of the service bulletin: Prior to further flight, reidentify the servo-valve in accordance with the service bulletin.
(3) If an Abex servo-valve has been installed and has a serial number not listed in either Table 1 or 2 of the service bulletin: No further action is required by this AD.
(b) As of the effective date of this AD, no FaireyHydraulics airbrake servo-valve assembly, part number 3799H1, shall be installed on any airplane unless that airbrake servo-valve assembly is in compliance with the requirements of this AD.
(c) 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, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Standardization Branch, ANM-113.
NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Standardization Branch, ANM-113.
(d) 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.
(e) The inspection, removal, replacement, and reidentification shall be done in accordance with British Aerospace BAe 146 Inspection Service Bulletin S.B. 27-133, dated January 31, 1992, which includes Appendix A1 to Service Bulletin S.B. 27-133, dated January 31, 1992. 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 British Aerospace, Inc., Avro Division, 22070 Broderick Drive, Sterling, Virginia 20166. 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., suite 700, Washington, DC.
(f) This amendment becomes effective on October 4, 1993.