91-02-02 BOEING: Amendment 39-6851. Docket No. 90-NM-125-AD. \n\n\tApplicability: Model 757 series airplanes, certificated in any category. \n\n\tCompliance: Required within the next 48 months after the effective date of this AD, unless previously accomplished. \n\n\tTo preclude cross connection of engine and cargo compartment fire extinguishing wiring and plumbing during maintenance, accomplish the following: \n\n\tA.\tModify the engine and cargo compartment fire extinguishing system wiring and plumbing in accordance with Boeing Service Bulletin 757-26-0020, dated March 22, 1990. Accomplishment of this modification constitutes terminating action for the repetitive inspections and functional tests required by Airworthiness Directive 89-03-51, Amendment 39-6213, on Boeing Model 757-200 airplanes following maintenance on the engine and cargo compartment fire extinguishing wiring and plumbing. \n\n\tNOTE: The modification required by this paragraph was incorporated in production on airplanes, line numbers 256 and subsequent. Accordingly, this paragraph terminates the repetitive inspection and functional test requirements of AD 89-03-51 for those airplanes. \n\n\tB.\tAn 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, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. \n\n\tNOTE: The request should be submitted directly to the Manager, Seattle ACO, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Seattle ACO. \n\n\tC.\tSpecial 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.\n \n\tAll persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Boeing Commercial AirplaneGroup, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. \n\n\tThis amendment (39-6851, AD 91-02-02) becomes effective on February 4, 1991.