91-06-20 BRITISH AEROSPACE: Amendment 39-6937. Docket No. 90-NM-241-AD.
Applicability: Model ATP series airplanes; Serial Numbers 2001 through 2020, inclusive; certificated in any category.
Compliance: Required as indicated, unless previously accomplished.
To prevent the malfunction of electrical equipment, overheat damage or fire, and the loss of electrical power, accomplish the following:
A. Within 90 days after the effective date of this AD, inspect the electrical cable ring tongue terminal tags listed in Tables 1 to 21 of British Aerospace Service Bulletin ATP-24-21, Revision 2, dated April 24, 1990, for security and discoloration, in accordance with the service bulletin.
NOTE: The service bulletin and this AD refer to "ring tongue terminal tags." That terminology is used to describe crimp-on wire terminals that have a loop on one end to fit over a terminal stud.
B. If any terminal tag shows signs of being insecurely crimped or is discolored, replace it prior to further flight, in accordance with British Aerospace Service Bulletin ATP-24-21, Revision 2, dated April 24, 1990.
C. Within 2,500 hours time-in-service, but not sooner than 2,000 hours time-in-service, following the inspection required by paragraph A. of this AD, perform a one-time repeat visual inspection on all listed terminal tags that have not been replaced or recrimped, in accordance with British Aerospace Service Bulletin ATP-24-21, Revision 2, dated April 24, 1990.
1. If any terminal tag shows signs of being insecurely crimped or is found discolored, replace it prior to further flight, in accordance with the service bulletin.
2. For those terminal tags which do not show signs of being insecurely crimped or discolored, no further action is required.
D. 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, StandardizationBranch, ANM-113, FAA, Transport Airplane Directorate.
NOTE: The request should be submitted directly to the Manager, Standardization Branch, ANM-113, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Manager, Standardization Branch, ANM-113.
E. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD.
All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to British Aerospace, PLC, Librarian for Service Bulletins, P.O. Box 17414, Dulles International Airport, Washington, D.C. 20041-0414. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington.
This amendment (39-6937, AD 91-06-20) becomes effective onApril 18, 1991.