88-24-13 FOKKER B.V.: Amendment 39-6070. Applies to Model F-28 series airplanes, Serial Numbers 11003 to 11241 inclusive, 11991, and 11992, certificated in any category. Compliance required as indicated, unless previously accomplished.
To prevent structural failure in the flap or rear spar web and fuel leakage, accomplish the following:
A. Prior to the accumulation of either 10,000 flight hours or 20,000 flight cycles (landings), or within 500 flight cycles (landings) after the effective date of this AD, whichever occurs later: Conduct an external visual inspection of the flap track beam support bracket for position in accordance with Part 1 of Fokker Service Bulletin F28/57-81, dated May 27, 1988.
B. If the flanges of the flap track beam support bracket are found during the inspection specified in A., above, to be parallel to the rear spar, no further action is required.
C. If the flanges of the flap track beam support bracket are found during the inspection specified in A., above, not to be parallel to the rear spar, inspect for cracks in the web of the rear spar, in accordance with Part 2 of service Bulletin F28/57-81, dated May 27, 1988, before further flight.
1. If no cracks are found, repeat the inspection every 1,000 flight cycles (landings) until an internal inspection is conducted in accordance with Part 3 of Service Bulletin F28/57-81, dated May 27, 1988.
2. If, during the inspections accomplished in accordance with Part 3 of Service Bulletin F28/57-81, dated May 27, 1988, it is determined that the bolts are installed properly, a spotface is not found, and cracking does not exist, reseal or reinstall the bolts in accordance with Part 3 of that service bulletin. No further action, other than restoration to normal, is required.
3. If cracks are found during the inspections required by paragraph C., C.1., or C.2., above, or if a spotface is found during the inspections required by paragraph C.1., or C.2., priorto further flight, repair in a manner approved by the Manager, FAA Brussels Aircraft Certification Office, AEU-100. Under conditions noted in the Service Bulletin F28/57-81, dated May 27, 1988, temporary repairs may be made in accordance with Part 4 and the associated table and figures of that service bulletin.
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/or modifications required by 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 Fokker Aircraft U.S.A., 1199 N. Fairfax Street, Alexandria, Virginia 22314. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or at the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington.
This amendment, 39-6070, becomes effective December 27, 1988.