AD 2001-04-15 Airworthiness Directives; McDonnell Douglas Model DC-8-31, DC-8-32, DC-8-33, DC-8-41, DC-8-42, DC-8-43, DC-8-51, DC-8-52, DC-8-53, DC-8-55, DC-8-61, DC-8-61F, DC-8-62, DC-8-62F, DC-8-63, DC-8-63F, DC-8F-54, and DC-8F-55 Series Airplanes

Models named: DC-8 series. Read the applicability below — it usually turns on serial or part numbers too.

The following Model DC-8 series airplanes that have been modified in accordance with Supplemental Type Certificate (STC) ST466CH, certificated in any category:         DC-8-31 DC-8-32 DC-8-33 DC-8-41 DC-8-42 DC-8-43 DC-8-51 DC-8-52 DC-8-53 DC-8-55 DC-8-61 DC-8-61F DC-8-62 DC-8-62F DC-8-63 DC-8-63F DC-8F-54 DC-8F-55 Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise 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 the pitot lines from freezing, which could result in erroneous or total loss of airspeed indications to the flight crew, and consequent loss of control of the airplane, accomplish the following: Modification (a) Within 30 days after the effective date of this AD, modify the flow control system to reroute the bleed air ducts, in accordance with National Aircraft Service, Inc., Service Bulletin SB-98-01R1, dated January 26, 1999. Alternative Methods of Compliance (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, Chicago Aircraft Certification Office (ACO), FAA. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Chicago ACO. Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Chicago ACO. Special Flight Permits (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. Incorporation by Reference (d) The actions shall be done in accordance with National Aircraft Service, Inc., Service Bulletin SB-98-01R1, dated January 26, 1999. 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 National Aircraft Service, Inc., 9133 Tecumseh-Clinton Road, Tecumseh, Michigan 49286. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Chicago Aircraft Certification Office, 2330 East Devon Avenue, Room 323, Des Plaines, Illinois; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. Effective Date (e) This amendment becomes effective on March 21, 2001. Issued in Renton, Washington, on February 22, 2001. Donald L. Riggin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 01-4933 Filed 3-5-01; 8:45 am] BILLING CODE 4910-13-P