AD 95-18-14

This amendment adopts a new airworthiness directive (AD) that is applicable to General Electric Company (GE) CF6 series turbofan engines. This action requires a more detailed fluorescent penetrant inspection process for GE CF6 series high pressure compressor rotor (HPCR) stage 3-9 spools. This amendment is prompted by an uncontained failure of the HPCR stage 3-9 spool attributed to a material defect located in the hub to web transition area of the stage 6 disk. The actions specified in this AD are intended to prevent an uncontained HPCR engine failure, which can result in damage to the aircraft.

Final rule; request for comments.

95-18-14 General Electric Company: Amendment 39-9361. Docket 95-ANE-51.
Applicability: General Electric Company (GE) CF6 series engines. These engines are installed on but not limited to Airbus Industries A300, A310, and A330 series; Boeing 747 and 767 series; and McDonnell Douglas DC10 and MD11 series aircraft. NOTE: 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 use the authority provided in paragraph (b) to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition, or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any engine from the applicability of this AD.
Compliance: Required as indicated, unless accomplished previously.
To prevent an uncontained high pressure compressor rotor (HPCR) engine failure, which can result in damage to the aircraft, accomplish the following:
(a) After the effective date of this AD all fluorescent penetrant inspections of HPCR stage 3-9 spools must be accomplished in accordance with the process described in GE All Operators' Wire, Subject: FPI of Deeps Disk Spools, Best Practices, dated August 10, 1995.
(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. 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: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Engine Certification Office.
(c) The actions required by this AD shall be accomplished in accordance with the following GE All Operators' Wire:

Document
Pages
Date
Subject: FPI of Deep Disk Spools, Best Practices
1-3
August 10, 1995
Total pages: 3.

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 General Electric Aircraft Engines, CF6 Distribution Clerk, Room 132, 111 Merchant Street, Cincinnati, OH 45246. 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.
(d) This amendment becomes effective on September 21, 1995.

The Federal Aviation Administration (FAA) has received a report of an uncontained failure of a General Electric Company (GE) CF6-50 high pressure compressor rotor (HPCR) stage 3-9 spool. The failure resulted from a low cycle fatigue crack originating from a material defect located in the hub to web transition area of the stage 6 disk. The FAA has determined that a more detailed fluorescent penetrant inspection process is required for these high pressure compressor rotor stage 3-9 spools. This condition, if not corrected, could result in an uncontained HPCR engine failure, which can result in damage to the aircraft.
The FAA has reviewed and approved the technical contents of GE All Operators' Wire, Subject: FPI of Deep Disk Spools, Best Practices, dated August 10, 1995, that describes a more detailed fluorescent penetrant inspection process for HPCR stage 3-9 spools.
Since an unsafe condition has been identified that is likely to exist or develop onother GE CF6 series engines of the same type design, this AD is being issued to prevent an uncontained HPCR engine failure, which can result in damage to the aircraft. This AD requires that a more detailed fluorescent penetrant inspection of the HPCR stage 3-9 spool be used whenever fluorescent penetrant inspection of these spools is accomplished. The actions are required to be accomplished in accordance with the All Operators' Wire described previously.
Since a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days. Comments Invited
Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to commenton this rule by submitting such written data, views, or arguments as they may desire. Communications should identify the Rules Docket number and be submitted in triplicate to the address specified under the caption "ADDRESSES." All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.
Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 95-ANE-51." The postcard will be date stamped and returned to the commenter.
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.
The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, 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 USC 106(g), 40101, 40113, 44701. 39.13 - [AMENDED]
2. Section 39.13 is amended by adding the following new airworthiness directive: