2002-10-07: High Pressure Turbine (HPT) Second Stage Airseals

2002-10-07 Pratt & Whitney: Amendment 39-12753. Docket No. 2001-NE-27-AD. Applicability: This airworthiness directive (AD) is applicable to Pratt & Whitney (PW) JT9D-59A, -70A, -7Q, and -7Q3 turbofan engines. These engines are installed on, but not limited to, Airbus Indusrie A300 series, Boeing 747 series, and McDonnell Douglas DC-10 series airplanes. Note 1: This AD applies to each engine 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 engines 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. Compliance: Compliance with this AD is required as indicated, unless already done. To prevent failure of high pressure turbine (HPT) second stage airseals due to cracks in the knife edges, which if not detected could result in uncontained engine failure and damage to the airplane, do the following: Inspections (a) Perform a fluorescent penetrant inspection of the HPT second stage airseal knife edges for cracks in accordance with procedures and return to service criteria contained in Accomplishment Instructions, Paragraphs 1 through 3, of PW Service Bulletin (SB) JT9D 6409, dated July 27, 2001, each time the HPT stage 1 and stage 2 rotors are separated. Remove from service those airseals that are determined to be unserviceable. 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, Engine Certification Office (ECO). Operators must submit their request through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, ECO. Note 2: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the ECO. Special Flight Permits (c) Special flight permits may be issued in accordance with 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 done. Documents That Have Been Incorporated By Reference (d) The inspection must be done in accordance with Pratt & Whitney Service Bulletin JT9D 6409, dated July 27, 2001. 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 Pratt & Whitney, 400 Main St., East Hartford, CT 06108; telephone (860) 565-8770; fax (860) 565-4503. Copies may be inspected, by appointment, at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; 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 June 27, 2002.