AD 90-17-17

90-17-17 AIRBUS INDUSTRIE: Amendment 39-6704. Docket No. 90-NM-31-AD.

Applicability: Model A310 and A300-600 series airplanes, equipped with Litton LTN 90 or LTN 90-100 Inertial Reference Units, certificated in any category.

Compliance: Required within 45 days after the effective date of this AD, unless previously accomplished.

To prevent the loss of accurate attitude and heading information, accomplish the following:

A. Remove the three inertial reference units (IRU), modify the wiring in Zone 121, and install modified IRU's, in accordance with the following service bulletins:

AIRPLANE MODEL SERVICE BULLETIN A310 A310-34-2052, Revision 1, dated December 7, 1989 A300-600 A300-34-6029, Revision 1, dated December 7, 1989

NOTE: These service bulletins reference Litton Service Bulletins 34-90-102 and 34-90-98 for additional instructions.

B. 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, 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.

C. 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 Airbus Industrie, Airbus Support Division, Avenue Didier Daurat, 31700 Blagnac France. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or the Standardization Branch, Marginal Way South, Seattle, Washington.

This amendment (39-6704, AD 90-17-17) becomes effective on September 21, 1990.