AD 98-01-03 Airworthiness Directives; Fokker Model F27 Mark 050 Series Airplanes

Models named: F27 Mark 050 series. Read the applicability below — it usually turns on serial or part numbers too.

Model F27 Mark 050 series airplanes, serial numbers 20103 through 20296 inclusive, 20304, 20305, 20308, and 20311; certificated in any category. Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (b) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Required as indicated, unless accomplished previously. To prevent accumulation of ice in the engine air intake duct and subsequent ingestion of ice into the engine, which could result in engine power fluctuations and reduced controllability of the airplane, accomplish the following: (a) Within 3 months after the effective date of this AD, modify the air outlet opening of the engine air bypass duct in the left and right bottom engine cowling in accordance with Fokker Service Bulletin SBF50-71-041, dated November 10, 1993. (b) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, International Branch, ANM-116. Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116. (c) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. (d) The modification shall be done in accordance with Fokker Service Bulletin SBF50-71-041, dated November 10, 1993. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Fokker Services B.V., Technical Support Department, P. O. Box 75047, 1117 ZN Schiphol Airport, the Netherlands. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. Note 3: The subject of this AD is addressed in Dutch airworthiness directive BLA 1995-065 (A), dated June 30, 1995. (e) This amendment becomes effective on January 15, 1998. Issued in Renton, Washington, on December 23, 1997. Darrell M. Pederson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 97-34040 Filed 12-30-97; 8:45 am] BILLING CODE 4910-13-U