AD 92-14-06

92-14-06 BRITISH AEROSPACE: Amendment 39-8288. Docket No. 92-NM-24-AD. Applicability: Model Viscount 810 series airplanes, certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent loss of elevator structural integrity and reduced controllability of the airplane, accomplish the following:

(a) Within 60 days after the effective date of this AD, visually inspect the external surface of the left and right elevator lower skins for skin quilting, corrosion, and delamination, in accordance with British Aerospace Viscount Alert Preliminary Technical Leaflet (PTL) 196, dated March 1991.

(b) As a result of the inspection required by paragraph (a) of this AD, accomplish the procedures specified in either paragraph (b)(1) or (b)(2) of this AD, as applicable, in accordance with British Aerospace Viscount Alert PTL 196, dated March 1991:

(1) If no discrepancies are detected, apply water displacing fluid andanti-corrosion protective treatment to the inner surfaces of the elevator lower skins, and rebalance the elevators.

(2) If any discrepancies are detected, prior to further flight, replace quilted, corroded, or delaminated skins with a single thickness skin; apply water displacing fluid and anti-corrosion protective treatment to the inner surfaces of the elevator lower skins; and rebalance the elevators.

(c) Repeat the visual inspection of the elevator skins required by paragraph (a) of this AD, and inspect the condition of the corrosion protective treatment inside the elevators, at intervals not to exceed 850 hours time-in-service or 12 months, whichever occurs first. Replace any quilted, corroded, or delaminated skins, and renew any deteriorated corrosion protective treatment, prior to further flight, in accordance with British Aerospace Viscount Alert Preliminary Technical Leaflet (PTL) 196, dated March 1991.

(d) An alternative method of compliance or adjustmentof 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.

NOTE: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Standardization Branch.

(e) 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.

(f) The inspection and replacement shall be done in accordance with British Aerospace Viscount Alert Preliminary Technical Leaflet (PTL) 196, dated March 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 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.

(g) This amendment becomes effective on August 20, 1992.