92-09-04 BRITISH AEROSPACE: Amendment 39-8229. Docket No. 91-NM-283-AD.
Applicability: All Viscount Model 744, 745D, and 810 series airplanes, certificated in any category.
Compliance: Required as indicated, unless accomplished previously.
To prevent failure of one or more of the landing gears, accomplish the following:
(a) Within 500 hours time in-service or within 6 months after the effective date of this AD, whichever occurs first, accomplish the following procedures in accordance with British Aerospace Viscount Alert Preliminary Technical Leaflet (PTL) 319 (for Model 744 and 745D series airplanes) or PTL 188 (for Model 810 series airplanes), both dated March 14, 1990, as applicable:
(1) Remove the nose and main landing gear retraction jacks. Remove the shuttle valve elbow connections, part numbers 70050-69 and 74450-117, and the shuttle, part number A5133-7, from the jacks, in accordance with the service bulletin.
(2) Ream the bore of each shuttle valve elbow connection, and chamfer the elbow bore aperture to 45 degrees. Remove the swarf and clean each shuttle valve elbow. If any residual obstructions or burrs are detected, prior to further flight, remove them in accordance with the service bulletin.
(3) Visually inspect the "hard chrome" plating of the shuttle for damage. If any damaged or binding shuttles are detected, prior to further flight, replace them with new parts, in accordance with the service bulletin.
(4) Visually inspect the bores in the retraction jack cylinder ends for obstructions. If any obstructions or damaged parts are detected, prior to further flight, remove or replace them in accordance with the service bulletin.
(5) Reassemble the shuttles and shuttle valve elbow connections to their respective retraction jacks. Immediately subsequent to installation and reassembly, perform bench checks on the retraction jack assemblies, in accordance with the Viscount Maintenance Manual, to ensure proper operation of the shuttle valves. If any malfunctioning parts are detected, prior to further flight, repair or replace them in accordance with the Maintenance Manual. Reinstall the retraction jacks on the airplane, bleed the hydraulic system and perform landing gear functioning checks in accordance with the Viscount Maintenance Manual. If any malfunctioning parts are detected, prior to further flight, replace or repair them in accordance with the Maintenance Manual.
(b) An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. The request shall be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Standardization Branch, ANM-113.
(c) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 tooperate the airplane to a location where the requirements of this AD can be accomplished.
(d) The inspection and repairs shall be done in accordance with British Aerospace Viscount Alert Preliminary Technical Leaflet (PTL) 319 (for Model 744 and 745D series airplanes), dated March 14, 1990; or PTL 188 (for Model 810 series airplanes), dated March 14, 1990. 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, PLC, Librarian for Service Bulletins, P.O Box 17414, Dulles International Airport, Washington, DC. 20041-0414. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington; or at the Office of the Federal Register, 1100 L Street NW., Room 8401, Washington, DC.
(e) This amendment becomes effective on June 2, 1992.