88-14-04 BRITISH AEROSPACE: Amendment 39-6003. Final copy of priority letter AD issued July 8, 1988. Applies to Viscount Model 700 and 800 series airplanes, certificated in any category. Compliance is required as indicated, unless previously accomplished.
To prevent structural failure of the wing, accomplish the following:
A. Within 7 days after the effective date of this AD, and thereafter at intervals not to exceed 12 months, accomplish the following:
1. Visually inspect the right and left upper wing surface between Wing Stations 96 and 131 above the main (center) spar upper cap for evidence of corrosion, in accordance with British Aerospace Campaign Wire REF FSS/VIS/886135, dated June 30, 1986. Signs of corrosion include lifting of the skin, loose fasteners, and corrosion stains around the fasteners.
2. Visually inspect the underside of the upper wing skin surface between Stations 96 and 131 both front and aft sides of the main (center) spar upper cap, both right and left wings, for evidence of corrosion, in accordance with British Aerospace Campaign Wire REF FSS/VIS/886135, dated June 30, 1988. This area is accessed through the main landing gear (MLG) bay.
B. If corrosion is found or suspected as a result of the inspections required by paragraph A., above, prior to further flight, remove the wing upper skin between wing stations 96 and 131 for more thorough inspection for corrosion, and repair or replace corrosion-damaged structures, if necessary, in accordance with a method approved by the Manager, Standardization Branch, ANM-113, FAA, Northwest Mountain Region.
C. An alternate means 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, Northwest Mountain Region.
NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who may add any comments and thensend it to the Manager, Standardization Branch, ANM-113.
D. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of the modifications required by this AD.
All persons affected by this directive who have not already received the appropriate service document from the manufacturer may obtain copies upon request to British Aerospace, Inc., Librarian for Service Bulletins, P.O. Box 17414, Dulles International Airport, Washington, D.C. 20041. This document may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington.
This AD was effective earlier to all recipients of Priority Letter AD 88-14-04, issued July 8, 1988.
This amendment, 39-6003, becomes effective September 6, 1988.