88-11-02 SAAB-FAIRCHILD: Amendment 39-5921. Applies to Model SF-340 series airplanes, listed in SAAB-SCANIA Service Bulletin SF340-33-016, Revision 1, dated April 3, 1987, certificated in any category.
Compliance required as indicated, unless previously accomplished.
To prevent electromagnetic interference with navigation and other systems, and the loss of the wheel brake system, accomplish the following:
A. Within 5 days following the effective date of this AD, incorporate the following, as applicable, into the limitations section of the airplane flight manual. This may be accomplished by including a copy of this AD in the airplane flight manual:
1. For airplanes that do not have the fluorescent lighting inverters modified in accordance with SAAB Service Bulletin SF340-33-021, dated June 12, 1987:
a. During all flight operations and ground operations with the engines running, deactivate the circuits providing power to the cabin internal overhead and window lights by first switching off these lights, and then opening circuits breakers numbers F24 and F25.
b. During operation with the cabin overhead and window lights deactivated, one reading light in each row must be turned on; or for those airplanes so configured, Row B on the flight attendant's panel must be selected "on".
2. For airplanes that have the fluorescent lighting inverters modified in accordance with SAAB Service Bulletin SF340-33-021, dated June 12, 1987: Prior to the first flight of the day, a crew member must inspect the cabin internal overhead and window lights to ensure that all fluorescent lamps are lit. If a lamp is not lit, it must be replaced prior to further flight, or the circuits which power the lamp must be deactivated.
B. Modification of the fluorescent lighting inverter assembly, P/N 18- 994, S/N 650- 1992 without blue dot, and inverter assembly P/N 18-966, S/N 1100- 3420 without blue dot, in accordance with SAAB Service Bulletin SF340-33-021, dated June 12, 1987, constitutes terminating action for the requirements of paragraph A.1., above.
C. Installation of Modification 1422, as described in SAAB-SCANIA Service Bulletin SF340-33-016, Revision 1, dated April 3, 1987, constitutes terminating action for the requirements of paragraph A. of this AD.
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, 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 then send it 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 for the accomplishment of inspections and modifications required by this AD.
All persons affected by this directive who have not alreadyreceived the appropriate service documents from the manufacturer may obtain copies upon request to SAAB-Fairchild, Product Support, S-58188, Linkoping, Sweden. These documents 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 Amendment 39-5921 supersedes AD 85-25-54 R1, Amendment 39-5760 (52 FR 41975; November 2, 1987).
This amendment, 39-5921, becomes effective June 3, 1988.