AD 87-16-12

87-16-12 BRITISH AEROSPACE: Amendment 39-5706. Applies to Model BAe-146 airplanes, as listed in British Aerospace BAe-146 Service Bulletin 27-58, Revision 1, dated November 14, 1986, certificated in any category. Compliance is required as indicated, unless previously accomplished.

To prevent an unannunciated failure of the stall identification system, accomplish the following:

A. Within 14 days or prior to the accumulation of 125 landings, whichever occurs first after the effective date of this AD, inspect the electro/pneumatic solenoid valve to identify the serial number and modification state in accordance with BAe-146 Service Bulletin 27-58, Revision 1, November 14, 1986. If the valve is identified as suspect, accomplish either of the following:

1. Prior to further flight, replace the affected valve with a modified valve identified in accordance with the service bulletin; or

2. Prior to further flight, and thereafter at intervals not to exceed 14 daysor 125 landings, whichever occurs first, functionally test the suspect valve in accordance with the Accomplishment Instructions of the service bulletin.

a. Valves found defective must be removed prior to further flight and replaced with modified valves or a serviceable suspect valve.

b. The serviceability of suspect replacement valves must be determined by performing the above mentioned functional test upon installation.

B. Replacement of suspect valves with modified valves identified in accordance with BAe-146 Service Bulletin 27-58, Revision 1, dated November 14, 1986, constitutes terminating action for the requirements of this AD.

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.

D. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operateairplanes to a base for the accomplishment of the modification required by this AD.

All persons affected by this directive who have not already received the appropriate service information from the manufacturer, may obtain copies upon request to British Aerospace, Librarian for Service Bulletins, P.O. Box 17414, Dulles International Airport, Washington, D.C. 20041. This information may be examined at FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington.

This amendment, 39-5706, becomes effective August 31, 1987.