[Federal Register Volume 61, Number 232 (Monday, December 2, 1996)] [Rules and Regulations] [Pages 63706-63707] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 96-30096] ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION 14 CFR Part 39 [Docket No. 96-ANE-02; Amendment 39-9821; AD 96-23-15] RIN 2120-AA64 Airworthiness Directives; Pratt & Whitney JT8D-200 Series Turbofan Engines AGENCY: Federal Aviation Administration, DOT. ACTION: Final rule. ----------------------------------------------------------------------- SUMMARY: This amendment supersedes an existing airworthiness directive (AD), applicable to Pratt & Whitney JT8D-200 series turbofan engines, that currently requires periodic inspection of fan blades for locked rotors and foreign object damage (FOD), unlocking of shrouds if necessary, lubrication of fan blade shrouds, and dimensional restoration of the fan blade leading edge. This amendment adds a requirement to install improved design fan blades as terminating action for the inspections. This amendment is prompted by the introduction into service of improved design fan blades. The actions specified by this AD are intended to prevent fan blade failure, which can result in damage to the aircraft. DATES: Effective January 2, 1997. The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of January 2, 1997. ADDRESSES: The service information referenced in this AD may be obtained from Pratt & Whitney, Publication Department, Supervisor Technical Publications Distribution, M/S 132-30, 400 Main St., East Hartford, CT 06108; telephone (860) 565-7700, fax (860) 565-4503. This information may be examined at the Federal Aviation Administration (FAA), New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA 01803-5299; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. FOR FURTHER INFORMATION CONTACT: Diane Cook, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone (617) 238- 7134, fax (617) 238-7199. SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding airworthiness directive (AD) 95-12-19, Amendment 39-9270 (60 FR 31388, June 15, 1995), applicable to certain Pratt & Whitney (PW) JT8D-200 series turbofan engines, was published in the Federal Register on May 6, 1996 (61 FR 20194). That action proposed to add a requirement to install improved design fan blades as terminating action for the periodic inspection of fan blades for locked rotors and foreign object damage (FOD), unlocking of shrouds if necessary, lubrication of fan blade shrouds, and dimensional restoration of the fan blade leading edge. The action would be required to be accomplished in accordance with PW Alert Service Bulletin (ASB) No. A6241, dated January 25, 1996. Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received. One commenter supports the rule as proposed. One commenter concurs with the inspection and maintenance provisions of the proposed AD. However, the commenter questions the proposed compliance schedule for the terminating action to incorporate the new fan blades. The compliance schedule is based on fan blade cycles in service (CIS). The commenter states that since (1) the fan blade fractures are due to a high cycle fatigue (HCF) failure mode that is not linked to total part CIS on the fan blade, and (2) that individual fan blade CIS are currently not tracked, an alternative compliance requirement based on completing a specific yearly percentage rate of the operator's engine sets would be less burdensome to the operators. The FAA concurs in part. When the FAA assessed the risk, the FAA based the compliance schedule on total part CIS. It has been the FAA's practice to define intervals for corrective action in an AD by means of part CIS. Monitoring this program on a fleet-wide basis using the suggested percentage rate would not provide the FAA with an adequate means to ensure that blades were removed before becoming a safety problem. Individual operators, however, may request such a percentage-based program that includes those assurances as an alternative method of compliance to the AD. The FAA, therefore, does not concur that the proposed AD should be revised. After careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed. The FAA estimates that 1,100 engines installed on aircraft of U.S. registry will be affected by this AD, that it will take approximately 19 work hours per engine to accomplish the required actions, and [[Page 63707]] that the average labor rate is $60 per work hour. The FAA also estimates that the parts modification will cost $1,020 per engine, which includes a manufacturer's discount of $1,700 per engine. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $2,376,000. The regulations adopted herein will not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. For the reasons discussed above, I certify that this action (1) is not a ``significant regulatory action'' under Executive Order 12866; (2) is not a ``significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption ADDRESSES. List of Subjects in 14 CFR Part 39 Air Transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. Adoption of the Amendment Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows: PART 39--AIRWORTHINESS DIRECTIVES 1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. Sec. 39.13 [Amended] 2. Sec. 39.13 is amended by removing Amendment 39-9270 (60 FR 31388, June 15, 1995) and by adding a new airworthiness directive, Amendment 39-9821, to read as follows: 96-23-15 Pratt & Whitney: Amendment 39-9821. Docket 96-ANE-02. Supersedes AD 95-12-19, Amendment 39-9270. Applicability: Pratt & Whitney (PW) Models JT8D-209,-217, -217A, -217C, and -219 turbofan engines that have not incorporated PW Service Bulletin (SB) No. 6193, dated October 31, 1994, or with fan blade, Part Numbers (P/N's) 798821, 798821-001, 808121, 808121-001, 809221, 811821, 851121, 851121-001, 5000021-02, 5000021-022, and 5000021-032 installed. These engines are installed on but not limited to McDonnell Douglas MD-80 series aircraft. Note 1: This airworthiness directive (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 (f) 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: Required as indicated, unless accomplished previously. To prevent fan blade failure, which can result in damage to the aircraft, accomplish the following: (a) Inspect fan blades and shrouds, unlock fan blade shrouds, lubricate fan blade shrouds, restore leading edge dimensions, and modify or install improved design fan blades in accordance with the schedule and procedures described in Parts 1, 2, and 3 of the Accomplishment Instructions of PW Alert Service Bulletin (ASB) No. A6241, dated January 25, 1996. (b) Modification of fan blades to the improved design configuration or installation of improved design fan blades in accordance with Part 3 of the Accomplishment Instructions of PW ASB No. A6241, dated January 25, 1996, constitutes terminating action to the inspections and maintenance actions described in Parts 1 and 2 of that ASB. (c) For the purpose of this AD, the accomplishment effective date to be used for determination of compliance intervals, as required by Section 2 of PW ASB No. A6241, dated January 25, 1996, is defined as the effective date of this AD. (d) For the purpose of this AD, ``repair'' as specified in Part 3, Paragraph A.(1)(b) of the Accomplishment Instructions of PW ASB No. A6241, dated January 25, 1996, is defined as the refurbishment of fan blades in accordance with Part 3, Paragraph C of the Accomplishment Instructions of PW ASB No. A6241, dated January 25, 1996. (e) Alternative methods of compliance that have been approved for AD 95-12-19 are applicable for this AD and additional approval is not required. (f) 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. The request should be forwarded through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Engine Certification Office. Note 2: Information concerning the existence of approved alternative method of compliance with this AD, if any, may be obtained from the Engine Certification Office. (g) 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 aircraft to a location where the requirements of this AD can be accomplished. (h) The actions required by this AD shall be done in accordance with the following Pratt & Whitney ASB: ---------------------------------------------------------------------------------------------------------------- Document No. Pages Revision Date ---------------------------------------------------------------------------------------------------------------- A6241................................... 1-14 Original................... January 25, 1996. ---------------------------------------------------------------------------------------------------------------- Total pages: 14. 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, Publication Department, Supervisor Technical Publications Distribution, M/S 132- 30, 400 Main St., East Hartford, CT 06108; telephone (860) 565-7700, fax (860) 565- 4503. Copies may be inspected at the FAA, New England Region, Office of the Assistant Chief 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. (i) This amendment becomes effective on January 2, 1997. Issued in Burlington, Massachusetts, on November 7, 1996. James C. Jones, Acting Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. 96-30096 Filed 11-29-96; 8:45 am] BILLING CODE 4910-13-U