Airworthiness Directives; General Electric Company CF6-80C2 and CF6-80E1 Series Turbofan Engines, 8161-8166 [E9-3868]

Download as PDF Federal Register / Vol. 74, No. 35 / Tuesday, February 24, 2009 / Rules and Regulations Actions and Compliance (f) Unless already done, do the following actions. (1) Within the next 10 hours time-inservice (TIS) after March 2, 2009 (the effective date of this AD): (i) For all aircraft not incorporating computer numeric control (CNC) machined elevator hinges, inspect and repair the left and right horizontal stabilizer rear pivot attachment installation following instruction ‘‘3. Rear Pivot Attachment Inspection,’’ of Gippsland Aeronautics Mandatory Service Bulletin SB–GA8–2002–02, Issue 5, dated November 13, 2008; and, (ii) For all aircraft, inspect the left and right rear attach bolt mating surfaces for damage or an out of square condition and replace the left and right rear attach bolts following instruction ‘‘5. Rear Attach Bolt Replacement,’’ of Gippsland Aeronautics Mandatory Service Bulletin SB–GA8–2002– 02, Issue 5, dated November 13, 2008. Reworking the mating surfaces by spotfacing is no longer acceptable. If the mating surfaces are damaged, not square, or were previously reworked by spotfacing the surface, replace the parts as specified in Gippsland Aeronautics Mandatory Service Bulletin SB– GA8–2002–02, Issue 5, dated November 13, 2008. (2) Within the next 10 hours TIS after March 2, 2009 (the effective date of this AD) and repetitively thereafter at intervals not to exceed 100 hours TIS or 12 months, whichever occurs first, for all aircraft: (i) Inspect the horizontal stabilizer externally following instruction ‘‘2. External Inspection (Lower flange, Stabilizer rear spar),’’ of Gippsland Aeronautics Mandatory Service Bulletin SB–GA8–2002–02, Issue 5, dated November 13, 2008; and (ii) Inspect the horizontal stabilizer internally following instruction ‘‘4. Internal Inspection,’’ of Gippsland Aeronautics Mandatory Service Bulletin SB–GA8–2002– 02, Issue 5, dated November 13, 2008. (3) Before further flight, if during the inspection required by paragraph (f)(2) of this AD any excessive local deflection or movement of the lower skin surrounding the lower pivot attachment, cracking, or working (loose) rivet is found, obtain an FAAapproved repair scheme from the manufacturer and incorporate this repair scheme. Due to FAA policy, the repair scheme for crack damage must include an immediate repair of the crack, not a repetitive inspection. Continued operational flight with unrepaired crack damage is not permitted. mstockstill on PROD1PC66 with RULES FAA AD Differences Note: This AD differs from the MCAI and/ or service information as follows: (1) ‘‘Requirement: 1. Daily Inspection (Stabilizer attach bolt)’’ of the service information requires a daily inspection of the stabilizer attach bolt. The daily inspection is not a requirement of this AD. Instead of the daily inspection, we require you to perform, within 10 hours TIS, ‘‘Requirement 3. Rear Pivot Attachment Inspection’’ and ‘‘Requirement 5. Rear Attachment Bolt Replacement’’ of the service information. Compliance with requirement 3. and 5. is a terminating action for the daily inspection, VerDate Nov<24>2008 16:27 Feb 23, 2009 Jkt 217001 and we are requiring these within 10 hours TIS after the effective date of this AD. (2) ‘‘Requirement: 2. External Inspection (Lower flange, Stabilizer rear spar)’’ of the service information does not specify any action if excessive local deflection or movement of lower skin, cracking, or working (loose) rivet is found. We require obtaining and incorporating an FAAapproved repair scheme from the manufacturer before further flight. (3) The MCAI does not state if further flight with known cracks is allowed. FAA policy is to not allow further flight with known cracks in critical structure. We require that if any cracks are found when accomplishing the inspection required in paragraph (f)(2) of this AD, you must repair the cracks before further flight. (4) The service information does not state that parts with spotfaced nut and bolt mating surfaces require replacement. However, the service information no longer allows reworking of the mating surfaces by spotfacing. We require that if any nut and bolt surfaces were previously reworked by spotfacing, you must replace the parts. Other FAA AD Provisions (f) The following provisions also apply to this AD: (1) Alternative Methods of Compliance (AMOCs): The Manager, Standards Office, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Doug Rudolph, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: (816) 329–4059; fax: (816) 329– 4090. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO. (2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service. (3) Reporting Requirements: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120–0056. Related Information (g) Refer to MCAI Civil Aviation Safety Authority AD No. AD/GA8/5, Amdt 2, dated January 22, 2009; and Gippsland Aeronautics Mandatory Service Bulletin SB–GA8–2002– 02, Issue 5, dated November 13, 2008, for related information. Material Incorporated by Reference (h) You must use Gippsland Aeronautics Mandatory Service Bulletin SB–GA8–2002– 02, Issue 5, dated November 13, 2008, to do PO 00000 Frm 00021 Fmt 4700 Sfmt 4700 8161 the actions required by this AD, unless the AD specifies otherwise. (1) The Director of the Federal Register approved the incorporation by reference of this service information under 5 U.S.C. 552(a) and 1 CFR part 51. (2) For service information identified in this AD, contact Gippsland Aeronautics, Attn: Technical Services, P.O. Box 881, Morwell Victoria 3840, Australia; telephone: +61 03 5172 1200; fax: +61 03 5172 1201; Internet: https://www.gippsaero.com. (3) You may review copies of the service information incorporated by reference for this AD at the FAA, Central Region, Office of the Regional Counsel, 901 Locust, Kansas City, Missouri 64106. For information on the availability of this material at the Central Region, call (816) 329–3768. (4) You may also review copies of the service information incorporated by reference for this AD at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call (202) 741–6030, or go to: https://www.archives.gov/federal_register/ code_of_federal_regulations/ ibr_locations.html. Issued in Kansas City, Missouri on February 17, 2009. Kim Smith, Manager, Small Airplane Directorate, Aircraft Certification Service. [FR Doc. E9–3758 Filed 2–23–09; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2007–28413; Directorate Identifier 2007–NE–25–AD; Amendment 39– 15826; AD 2009–05–02] RIN 2120–AA64 Airworthiness Directives; General Electric Company CF6–80C2 and CF6– 80E1 Series Turbofan Engines AGENCY: Federal Aviation Administration (FAA), Department of Transportation (DOT). ACTION: Final rule. SUMMARY: The FAA is adopting a new airworthiness directive (AD) for General Electric Company (GE) CF6–80C2 and CF6–80E1 series turbofan engines with fuel manifolds part numbers (P/Ns) 1303M31G12 and 1303M32G12, installed in drainless fuel manifold assemblies (introduced by GE Aircraft Engines (GEAE) Service Bulletins (SB) CF6–80C2 S/B 73–0253 and CF6–80E1 S/B 73–0026). This AD requires removing the loop clamps that hold the fuel manifold to the compressor rear frame (CRF) damper brackets, inspecting the fuel manifold for wear at each clamp E:\FR\FM\24FER1.SGM 24FER1 8162 Federal Register / Vol. 74, No. 35 / Tuesday, February 24, 2009 / Rules and Regulations mstockstill on PROD1PC66 with RULES location, and replacing the clamps with new, zero-time parts. This AD also requires revising the Airworthiness Limitations Section (ALS) of the Instructions for Continued Airworthiness (ICA) and air carrier’s Continuous Airworthiness Maintenance Programs (CAMP) to require repetitive fuel manifold inspection and loop clamp replacement. This AD results from reports of fuel leaks during engine operation. We are issuing this AD to prevent fuel leaks that could result in an under-cowl fire and damage to the airplane. DATES: This AD becomes effective March 31, 2009. ADDRESSES: The Docket Operations office is located at Docket Management Facility, U.S. Department of Transportation, 1200 New Jersey Avenue, SE., West Building Ground Floor, Room W12–140, Washington, DC 20590–0001. FOR FURTHER INFORMATION CONTACT: Robert Green, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: Robert.green@faa.gov; telephone (781) 238–7754; fax (781) 238–7199. SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39 with a proposed AD. The proposed AD applies to GE CF6–80C2 and CF6–80E1 series turbofan engines with fuel manifolds P/Ns 1303M31G12 and 1303M32G12 installed in drainless fuel manifold assemblies. These drainless fuel manifold assemblies were introduced by GEAE SBs CF6–80C2 S/ B 73–0253 and CF6–80E1 S/B 73–0026. We published the proposed AD in the Federal Register on September 7, 2007 (72 FR 51388). That action proposed to require removing and discarding the loop clamps that assemble the fuel manifolds to the CRF damper brackets, inspecting the fuel manifolds for wear at each clamp location, and replacing the clamps. That action also proposed to require revising the ICA ALS and air carrier’s CAMP to require repetitive fuel manifold inspection and loop clamp replacement during each inspection. Examining the AD Docket You may examine the AD docket on the Internet at https:// www.regulations.gov; or in person at the Docket Operations office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone VerDate Nov<24>2008 16:27 Feb 23, 2009 Jkt 217001 (800) 647–5527) is provided in the section. Comments will be available in the AD docket shortly after receipt. ADDRESSES Comments We provided the public the opportunity to participate in the development of this AD. We have considered the comments received. Request To Clarify Inspection Requirements GE and two air carriers request that we clarify that the AD inspection requirements are specific to the drainless fuel manifold configuration, which was introduced by GEAE SB CF6–80C2 S/B 73–0253 (–80C2) and SB CF6–80E1 S/B 73–0026 (–80E1). We agree. We changed the AD to clarify the applicability and inspection requirements. Request for a Phase-in Period FedEx Express requests that we add a phase-in period for engines that might not have been part of a repetitive inspection program before the effective date of the AD. The commenter states that these engines would immediately fall out of compliance with the AD if they exceed the 7,500 flight-hour timesince-new (TSN) threshold for new, zero-time loop clamps, assuming the loop clamps were installed at the last shop visit. The commenter states that their fleet is almost entirely configured with drained manifold assemblies. They have not experienced any significant wear, and likely will have several engines exceeding the specified flighthour life limit in the AD. We partially agree. As we stated in the first comment response, this AD applies only to drainless manifold assemblies, so that portion of FedEx’s comment is not relevant to this AD. The need for a phase-in period is valid. We received another comment on that point and we changed the AD to accommodate the concerns. That discussion follows below. Incorrect Service Bulletin Reference GE, the Air Transport Association, Boeing Commercial Airplanes, and seven carriers point out that the proposed AD incorrectly referenced SB GEAE CF6–80C2 S/B 73–0226, for the manifold inspection. The appropriate SB is CF6–80C2 S/B 73–0326. We agree. We changed the reference in the AD. PO 00000 Frm 00022 Fmt 4700 Sfmt 4700 Comment That Clamp Wear Is Also Applicable to Drained Fuel Manifold Assemblies Air New Zealand Ltd and KLM Royal Dutch Airlines comment that the clamp wear problem is also applicable to fuel manifolds P/N 1303M31G10 and P/N 1303M32G10 installed in the drained fuel manifold assembly, pre-SB CF6– 80C2 S/B 73–0253 configuration. We do not agree. We are aware of only one leak found from loop clamp wear on a drained fuel manifold assembly, which was on a CF6–80C2 series turbofan engine. Considering the service history of the drained fuel manifold assembly, a mandatory inspection is not warranted at this time. We did not change the AD. Request To Apply the Re-Inspection Interval to Engines That Have Had New, Zero-Time Loop Clamps Installed On-Wing Air New Zealand Ltd and KLM Royal Dutch Airlines note that the proposed AD requires a 7,500 flight-hour reinspection interval for first-run engines and engines that have new, zero-time loop clamps installed at last shop visit. The commenters request that we apply the same re-inspection interval to engines that have had new, zero-time loop clamps installed on-wing. Air New Zealand states that they have been replacing loop clamps with new, zerotime loop clamps when they perform on-wing inspections of the fuel manifolds. We agree. We changed the AD to include on-wing replacement of loop clamps. Request for Credit for Installing Loop Clamps On-Wing All Nippon Airways requests that the AD initial inspection state that the 7,500 re-inspection interval for first-run engines or engines that have had new, zero-time loop clamps previously installed, apply regardless of previous inspection per GEAE SB CF6–80C2 S/B 73–0326 or SB CF6–80E1 S/B 73–0061. The commenter points out that the proposed AD does not recognize that operators were replacing the loop clamps on-wing. We agree. We changed the AD to clarify that the re-inspection requirement is not preempted by compliance with existing SB inspection recommendations. Request To Consider Using Room Temperature Vulcanizing (RTV) Rubber Compound Air India requests that we consider allowing the use of red, roomtemperature vulcanizing (RTV) rubber E:\FR\FM\24FER1.SGM 24FER1 Federal Register / Vol. 74, No. 35 / Tuesday, February 24, 2009 / Rules and Regulations compound (Specification A15F6B6; RTV 106; MIL–846106), between the loop clamps and fuel manifold when the loop clamps are replaced with new, zero-time parts at inspection. Air India states that they have applied RTV rubber compound on the inner diameter of loop clamps where they have observed wear on other engine tubing. GE previously recommended using RTV rubber compound on the low-pressure turbine cooling manifolds, and Air India now uses it at other locations. We do not agree. We have no data or experience to justify use of RTV rubber compound in this application. We did not change the AD. Recommendation To Use Fiberglass Tape The Air Transport Association and American Airlines recommend that we revise the proposed AD to allow the optional use of fiberglass tape on the fuel manifolds under the loop clamps. The commenters state that using the tape will eliminate the wear and reduce the effects of vibration by improving the fit of the clamps on the fuel manifolds. American Airlines states that they have been installing the fiberglass tape on their fuel manifolds at the time of inspection and loop clamp replacement since the beginning of their program. They believe the tape is essential to preventing fuel manifold wear. We do not agree. We reviewed the data GE provided and concluded that using fiberglass tape may contribute to the fuel manifold wear. GE has also stated that they no longer recommend fiberglass tape for this application. We did not change the AD. mstockstill on PROD1PC66 with RULES Request for a Unique Compliance Recommendation and Re-Inspection Interval Lufthansa Technik AG and a private citizen request a unique compliance recommendation and re-inspection interval for engines that had been previously inspected and or reassembled with new, zero-time loop clamps, with fiberglass tape between the loop clamps and fuel manifolds. Lufthansa Technik AG states that they have observed less wear when using the fiberglass tape. We do not agree. As previously noted, GE has stated that they no longer recommend fiberglass tape for this application. We did not change the AD. Request To Not Remove Fiberglass Tape Lufthansa Technik AG and GE Aviation request that we revise the fuel manifold inspection to not require removal of tape between the loop clamp VerDate Nov<24>2008 16:27 Feb 23, 2009 Jkt 217001 and fuel manifold, unless wear is observed on the tape. GEAE SB CF6– 80C2 S/B 73–0326, dated March 5, 2003, introduced the option of installing fiberglass tape on CF6–80C2 series engines. Lufthansa Technik AG states that if there is no wear found on the tape, then there will be no wear on the fuel manifold. Removing and replacing all tape at the time of inspection will add additional unnecessary work-hours to the inspection. We do not agree. As noted earlier, the tape may contribute to the wear, and GE no longer recommends fiberglass tape for this application. GE’s comment was in anticipation of a future design change with Teflon tape between the loop clamps and fuel manifolds. We did not change the AD. Request That the AD Recognize the Use of Teflon Tape GE Aviation and five air carriers request that the AD recognize the use of Teflon tape between new, zero-time loop clamps and fuel manifolds. The commenters request that we allow these engines to continue in service until the next inspection, without limit or penalty. The air carriers state that they have already been installing Teflon tape between new, zero-time loop clamps and fuel manifolds. We do not agree. We have no data or experience to make a determination for reducing or extending the inspection and loop clamp replacement intervals because of installing Teflon tape between the loop clamps and fuel manifolds. GE has certified new fuel manifolds with PTFE tape installed at the loop clamp locations. These parts have the same inspection and loop clamp replacement requirements as the original parts. We did not change this AD. Request for Clarification of Compliance Inspection Schedule Lufthansa Technik AG and Virgin Atlantic Airways request that we clarify whether a poorly fitting loop clamp, with or without tape, would compromise the compliance inspection schedule in the AD. We respond that it would not compromise the compliance inspection schedule in the AD. We concluded that replacing the loop clamps every 7,500 flight-hours (FH) was appropriate based on a GE Weibull analysis of the engine fleet, the first five fuel leak failures, and the accrued operation of 1,289 engines that had no leaks. The data was from first-run engines, which encompasses typical production loop clamp stack-up variations without tape. None of the subsequent leaks and failures occurred PO 00000 Frm 00023 Fmt 4700 Sfmt 4700 8163 with less time than the proposed AD inspection compliance interval of 7,500 FH. We did not change the AD. Request To Specify Flight Hours TimeSince-Last-Inspection or Flight Hours Time-Since-Last-Shop Visit Japan Airlines International requests that for clarification, the initial inspection schedule should specify FH time-since-last-inspection or FH timesince-last-shop visit as of the issue date of the AD. We partially agree. The initial inspection schedule is defined relative to the last inspection or replacement of the loop clamps with new clamps. However, for those engines that exceed the 1,750 and 4,500 FH thresholds, the determination is made as of the effective date of the AD. We changed the AD to clarify this. Request To Offset the Initial Inspection Schedule Japan Airlines International requests that we offset the initial inspection schedule to accommodate the scheduling of maintenance. We do not agree. The time for scheduling maintenance varies among operators. Defining a generic inspection threshold to accommodate this variation would introduce risk that the inspection schedule would be ambiguous. We did not change the AD. Propose an Additional Inspection Category Japan Airlines International proposes an additional inspection category for operators inspecting the manifolds at intervals longer than the GErecommended 4,500 FH interval. The commenter proposes that in these cases, operators would initially replace the loop clamps and inspect the fuel manifolds using their existing inspection schedule or within 4 months, whichever occurs first. The commenter states that they currently inspect affected fuel manifolds at 6,000 FH intervals, and based on the wording in the proposed AD, engines would be immediately in violation of the inspection requirements once the AD is effective. We partially agree. The commenter points out the need to include a transitional period for operators who are inspecting the fuel manifolds at intervals longer than the earlier GE inspection SB recommendation, which is engines operating with more than 4,500 FH time-since-last-inspection or time-since-last-shop visit. We changed the AD to include a four-month transition period, to bring these engines into compliance. E:\FR\FM\24FER1.SGM 24FER1 8164 Federal Register / Vol. 74, No. 35 / Tuesday, February 24, 2009 / Rules and Regulations Request To Permit Alternate Methods of Measuring Japan Airlines International and GE Aviation request that we permit alternate methods of measuring the depth of wear in fuel manifolds, such as ultrasonic wall thickness measurement. The commenters note that the proposed AD requires using a pinpoint micrometer to measure depth of wear. Because of limited access at the top of the installed engine, the commenter states it is not possible to use a pinpoint micrometer. We partially agree. GE does not have a procedure for ultrasonic inspections of the fuel manifolds for depth of wear. However, we agree that equivalent measuring techniques are acceptable. We eliminated the requirement to use a pinpoint micrometer. Request for Clarification of the Use of Part Manufacturer Approval (PMA) Loop Clamps Japan Airlines International requests clarification on the use of PMA loop clamps. The commenter asks if the proposed AD also applies to PMA loop clamps, part number VL1039GE2–10. Yes, the AD applies to PMA loop clamps. They are also susceptible to deteriorating and causing fuel leaks. We changed the AD to include a reference to PMA loop clamps. mstockstill on PROD1PC66 with RULES Question on Compliance Time Selection KLM Royal Dutch Airlines questions the selection of the proposed AD compliance time of 1,750 FH time-sincelast-inspection (TSLI). The commenter asks why we did not base the compliance recommendation on the low-time TSLI fuel manifold leak event for an engine with used loop clamps, which is 350 FH. The commenter also asks why we did not use the next lowest-time fuel manifold leak event, which is 2,000 FH TSLI. The commenter cites data presented by GE at the CF6 Technical Symposium on May 9 through May 10, 2007. We do not agree. Since 2005, the fuel manifold leak failure rate has increased. There were four leak events in 2006, six in 2007, and six to date in 2008. Thirteen of the events are known to have occurred before the GErecommended 4,500 FH re-inspection interval. The average TSLI for the thirteen failures is 2,250 FH. The 350 FH leak is a low-time event relative to the other failures and is believed to be unique. The 1,750 FH TSLI compliance requirement was based on the nextlowest TSLI leak event at the time, which was after the GE CF6 Technical Symposium. We did not change the AD. VerDate Nov<24>2008 17:14 Feb 23, 2009 Jkt 217001 Question on Why the Compliance Time Is Extended KLM Royal Dutch Airlines questions why the proposed AD extends the 1,750 FH TSLI compliance time to 4,500 FH TSLI or 4 months after the effective date of the AD, for engines with used clamps or clamps of unknown heritage that have already accumulated more than 1,750 FH. The commenter is concerned that this 4-month compliance period will increase the probability of a fuel manifold leak event. We do not agree. The proposed inspection and loop clamp replacement schedule for engines that already exceed the 1,750 FH threshold is an effort to transition the engine fleet to new loop clamps within a reasonable period of time. This will be achieved either through the original GE-recommended 4,500 FH schedule or within 4 months, whichever comes first. We did not change the AD. Question on GE’s Risk Assessment KLM Royal Dutch Airlines questions why we disregarded GE’s risk assessment that justified the 4,500 FH inspection interval. We did because GE’s risk assessment predicted fuel manifold leak events within the 4,500 FH inspection intervals. As previously noted, the leaking fuel could ignite resulting in an under-cowl fire and damage to the airplane, which is unacceptable. Recommendation That We Eliminate Revising the Air Carrier’s Approved CAMP and ALS of Chapter 5 The Air Transport Association and U.S. Airways recommend that we eliminate the requirement to revise the air carrier’s approved CAMP and ALS of Chapter 5 in the CF6–80C2 and CF6– 80E1 Instructions for Continued Airworthiness (ICA) from the proposed AD. The commenters state that GE has indicated it is developing new-design fuel manifolds to eliminate the repetitive maintenance required by this AD. We do not agree. The AD requires GE to revise the ALS of the ICAs, and air carriers to revise their CAMP, to specify the repetitive inspections and loop clamp replacements for the drainless fuel manifold assemblies with fuel manifold P/N 1303M31G12 and P/N 1303M32G12. The AD would not be applicable to a new design. We did not change the AD. Request To Change the Proposed AD Discussion GE Aviation requests that we change the proposed AD Discussion to state that abrasive dirt and debris collecting PO 00000 Frm 00024 Fmt 4700 Sfmt 4700 between the worn loop clamps and fuel manifolds can result in fuel manifold wear with loop clamps that appear serviceable. We partially agree. The deterioration of the loop clamp and possible accumulation of dirt and debris between the loop clamp cushion and fuel manifold might contribute to fuel manifold wear, but if so, it is a secondary factor. The root cause of the fuel manifold wear is fuel manifold vibration during engine operation. We did not change the AD. Request To Consider the Probability of an Under-Cowl Fire GE Aviation requests that we consider a longer inspection/replacement interval, and requests that we consider the probability of an under-cowl engine fire if we use 4,500 flight-hours instead. GE Aviation requests that we consider an intermediate compliance time that is supportable by industry if the 4,500 FH does not sufficiently reduce the risk of an under-cowl fire. GE states that our proposed 1,750 FH TSLI interval will reduce the average time between inspections from 15 months to less than 6 months, and increase the number of engines that will need to be inspected per week during the transition by a factor of 2.5. This will severely burden industry’s maintenance capacity. GE also states that the additional work required to bring engines that already exceed the 1,750 FH into compliance, during the 4-month grace period, will make the burden worse. We partially agree. The commenter did not consider first-run engines or engines that have already had new, zero-time loop clamps installed during either last shop visit or an earlier inservice inspection. We also note that despite the GE 4,500 FH TSLI SB recommendation, one fuel leak event occurred in 2005, four occurred in 2006, and six fuel leak events occurred in 2007. Nine of these 11 events occurred within the recommended 4,500 FH interval. We agree that the lack of a calendar compliance period with the 1,750 FH threshold could result in an immediate maintenance scheduling problem and we changed the AD to include the 4-month compliance period with the 1,750 FH threshold to facilitate the transition. Request To Revise Costs of Compliance Japan Airlines International and GE Aviation request that we revise the Costs of Compliance. GE Aviation estimates that 2 work-hours are required to inspect the loop clamps and fuel manifolds. Japan Airlines estimates that E:\FR\FM\24FER1.SGM 24FER1 Federal Register / Vol. 74, No. 35 / Tuesday, February 24, 2009 / Rules and Regulations based on their experience, 8 work-hours are required for the inspections. We do not agree. In recognizing the possible work-hour variations from operator to operator, we believe that 4 work-hours is a valid average. We did not change the AD. Conclusion We have carefully reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD. Costs of Compliance We estimate that this AD will affect 350 CF6–80C2 series turbofan engines installed on airplanes of U.S. registry. We also estimate that it will take about 4 work-hours per engine to perform the actions, and that the average labor rate is $80 per work-hour. Required parts will cost about $162 per engine. Based on these figures, we estimate the total cost of the AD to U.S. operators for a once-through-the-fleet manifold visual inspection and loop clamp replacement to be $168,700. Authority for This Rulemaking Title 49 of the United States Code specifies the FAA’s authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency’s authority. We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, ‘‘General requirements.’’ Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. Regulatory Findings We have determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect 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. For the reasons discussed above, I certify that this AD: (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. We prepared a summary of the costs to comply with this AD and placed it in the AD Docket. You may get a copy of this summary at the address listed under ADDRESSES. List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Safety. Adoption of the Amendment Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration amends 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. § 39.13 [Amended] 2. The FAA amends § 39.13 by adding the following new airworthiness directive: ■ 2009–05–02 General Electric Company: Amendment 39–15826. Docket No. FAA–2007–28413; Directorate Identifier 2007–NE–25–AD. 8165 Effective Date (a) This airworthiness directive (AD) becomes effective March 31, 2009. Affected ADs (b) None. Applicability (c) This AD applies to: (1) General Electric (GE) CF6–80C2A1, –80C2A2, –80C2A3, –80C2A5, –80C2A8, –80C2A5F, –80C2B1, –80C2B2, –80C2B4, –80C2B6, –80C2B1F, –80C2B1F1, –80C2B1F2, –80C2B2F, –80C2B3F, –80C2B4F, –80C2B5F, –80C2B6F, –80C2B6FA, –80C2B7F, –80C2B8F, –80C2D1F, –80C2L1F, –80C2K1F turbofan engine models with fuel manifold part numbers (P/Ns) 1303M31G12 and 1303M32G12, installed in drainless fuel manifold assemblies (introduced by GE Aircraft Engines (GEAE) Service Bulletin (SB) CF6–80C2 S/B 73–0253). These engines are installed on, but not limited to, Boeing 747, 767, MD11, and Airbus A300–600 and A310 airplanes. (2) This AD also applies to GE CF6– 80E1A1, –80E1A2, –80E1A3, –80E1A4, –80E1A4/B turbofan engine models with fuel manifold P/Ns 1303M31G12 and 1303M32G12, installed in drainless fuel manifold assemblies (introduced by GEAE SB CF6–80E1 S/B 73–0026). These engines are installed on Airbus A330 airplanes. Unsafe Condition (d) This AD results from reports of fuel leaks during engine operation. We are issuing this AD to prevent fuel leaks that could result in an under-cowl fire and damage to the airplane. Compliance (e) You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done. Removal and Replacement of Loop Clamps and Fuel Manifold Inspection Compliance Times (f) Using Table 1 of this AD, Schedule for Inspections and Replacements, accomplish the following actions in the intervals indicated in the table: remove and discard all loop clamps, P/N J1220G10, or part manufacturer approval (PMA) equivalent, that hold the fuel manifold to the compressor rear frame (CRF) friction damper brackets. Inspect the fuel manifold for wear at each clamp location as specified in paragraphs (g) and (h) of this AD. Replace the discarded loop clamps with new, zero-time clamps. TABLE 1—SCHEDULE FOR INSPECTIONS AND REPLACEMENTS mstockstill on PROD1PC66 with RULES If: Then replace clamps and inspect within: (1) The engine was previously inspected using GEAE SB CF6–80C2 S/ B 73–0326, dated March 5, 2003, for CF6–80C2 engines; or GEAE SB CF6–80E1 S/B 73–0061, dated April 14, 2003, for CF6–80E1 engines. (2) Used loop clamps or clamps of unknown heritage were installed at last shop visit. 1,750 flight hours (FH) time-since-last-inspection (TSLI) or within 4 months after the effective date of this AD. VerDate Nov<24>2008 16:27 Feb 23, 2009 Jkt 217001 PO 00000 Frm 00025 Fmt 4700 1,750 FH time-since-last-shop-visit or within 4 months after the effective date of this AD. Sfmt 4700 E:\FR\FM\24FER1.SGM 24FER1 8166 Federal Register / Vol. 74, No. 35 / Tuesday, February 24, 2009 / Rules and Regulations TABLE 1—SCHEDULE FOR INSPECTIONS AND REPLACEMENTS—Continued If: Then replace clamps and inspect within: (3) The engine is a first-run engine or is an engine with zero-time, new loop clamps previously installed on-wing or at shop visit. 7,500 FH time-since-new or since zero-time, new loop clamps were installed (regardless if previously inspected per GEAE SB CF6–80C2 S/B 73–0326 or GEAE SB CF6–80E1 S/B 73–0061). 4,500 FH TSLI, or 4 months after the effective date of this AD, whichever occurs first. (4) The engine has already exceeded the 1,750 FH initial inspection threshold on the effective date of this AD, but has fewer than 4,500 flight hours TSLI. (5) The engine has already exceeded the 4,500 FH initial inspection threshold on the effective date of this AD. Inspection of Fuel Manifold P/Ns 1303M31G12 and 1303M32G12 (g) Remove any tape at any clamp location. Visually inspect the full circumference of the manifold for wear at each clamp location. If any wear is found, follow paragraph (h) of this AD. (h) When the fuel manifold shows any signs of wear, determine the depth of the wear as follows: (1) Measure the outside diameter of the tube adjacent to the worn area. (2) Measure the worn area at the smallest diameter. (3) Subtract the measurement of the worn tube diameter from the unworn diameter measurement. Allowable wear is 0.0035 inch. (4) Replace fuel manifolds with wear greater than 0.010 inch before further flight. (5) Replace fuel manifolds with wear greater than 0.0035 inch but less than 0.010 inch, within 50 flight cycles. Revise Air Carrier’s Continuous Airworthiness Maintenance Program (CAMP) and Airworthiness Limitation Section (ALS) (i) Within 30 days of the effective date of this AD, revise the air carrier’s approved CAMP and Instructions for Continued Airworthiness (ICA) Chapter 5, Airworthiness Limitation Section for the CF6–80C2 and CF6–80E1 series engines to require: (1) Repetitive inspections of fuel manifolds, P/Ns 1303M31G12 and 1303M32G12, installed in drainless fuel manifold assemblies introduced by CF6– 80C2 S/B 73–0253 and CF6–80E1 S/B 73– 0026, as detailed in paragraphs (g) and (h) of this AD, at 7,500 FH intervals. (2) Mandatory removal of all loop clamps that hold the fuel manifold, P/Ns 1303M31G12 and 1303M32G12, to the CRF damper brackets, at each inspection. (3) Replacement of all loop clamps with new, zero-time loop clamps, at each inspection. mstockstill on PROD1PC66 with RULES Alternative Methods of Compliance (j) The Manager, Engine Certification Office, has the authority to approve alternative methods of compliance for this AD if requested using the procedures found in 14 CFR 39.19. Related Information (k) GEAE SB CF6–80C2 S/B 73–0326, dated March 5, 2003, and GEAE SB CF6–80E1 S/ B 73–0061, dated April 14, 2003; and the following GE engine manuals pertain to the subject of this AD: VerDate Nov<24>2008 16:27 Feb 23, 2009 Jkt 217001 4 months after the effective date of this AD. (1) CF6–80C2 Engine Manual GEK 92451. (2) CF6–80C2L1F Engine Manual GEK 112213. (3) CF6–80C2K1F Engine Manual GEK 112721. (4) CF6–80E1 Engine Manual GEK 99376. (l) Contact General Electric Company via Lockheed Martin Technology Services, 10525 Chester Road, Suite C, Cincinnati, Ohio 45215; telephone (513) 672–8400; fax (513) 672–8422, for the service information identified in this AD. (m) Contact Robert Green, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: Robert.green@faa.gov; telephone (781) 238–7754; fax (781) 238– 7199, for more information about this AD. DATES: Effective Date: 0901 UTC, May 7, 2009. The Director of the Federal Register approves this incorporation by reference action under 1 CFR Part 51, subject to the annual revision of FAA Order 7400.9 and publication of conforming amendments. FOR FURTHER INFORMATION CONTACT: Scott Enander, Central Service Center, Operations Support Group, Federal Aviation Administration, Southwest Region, 2601 Meacham Blvd., Fort Worth, TX 76193–0530; telephone (817) 321–7716. SUPPLEMENTARY INFORMATION: AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. History On December 18, 2008, the FAA published in the Federal Register a notice of proposed rulemaking to amend Class E airspace at Columbus, OH, adding additional controlled airspace at Rickenbacker International Airport, Columbus, OH. (73 FR 76985, Docket No. FAA–2008–1185). Interested parties were invited to participate in this rulemaking effort by submitting written comments on the proposal to the FAA. No comments were received. Class E airspace designations are published in paragraph 6005 of FAA Order 7400.9S signed October 3, 2008, and effective October 31, 2008, which is incorporated by reference in 14 CFR Part 71.1. The Class E airspace designations listed in this document will be published subsequently in that Order. With the exception of editorial changes, and the changes described above, this rule is the same as that proposed in the NPRM. SUMMARY: This action amends Class E airspace at Columbus, OH. Additional controlled airspace is necessary to accommodate Area Navigation (RNAV) Standard Instrument Approach Procedures (SIAP) at Rickenbacker International Airport, Columbus, OH. This action also makes a minor change to the geographical coordinates of Bolton Field Airport, Columbus, OH. The FAA is taking this action to enhance the safety and management of Instrument Flight Rule (IFR) operations at Rickenbacker International Airport. The Rule This action amends Title 14 Code of Federal Regulations (14 CFR) Part 71 by amending Class E airspace at Columbus, OH, adding additional controlled airspace at Rickenbacker International Airport, Columbus, OH., and makes a minor change to the geographical coordinates of Bolton Field Airport, Columbus, OH. The FAA has determined that this regulation only involves an established body of technical regulations for which frequent and routine amendments are Issued in Burlington, Massachusetts, on February 17, 2009. Thomas A. Boudreau, Acting Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. E9–3868 Filed 2–23–09; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 71 [Docket No. FAA–2008–1185; Airspace Docket No. 08–AGL–11] Amendment of Class E Airspace; Columbus, OH PO 00000 Frm 00026 Fmt 4700 Sfmt 4700 E:\FR\FM\24FER1.SGM 24FER1

Agencies

[Federal Register Volume 74, Number 35 (Tuesday, February 24, 2009)]
[Rules and Regulations]
[Pages 8161-8166]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E9-3868]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-28413; Directorate Identifier 2007-NE-25-AD; 
Amendment 39-15826; AD 2009-05-02]
RIN 2120-AA64


Airworthiness Directives; General Electric Company CF6-80C2 and 
CF6-80E1 Series Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
General Electric Company (GE) CF6-80C2 and CF6-80E1 series turbofan 
engines with fuel manifolds part numbers (P/Ns) 1303M31G12 and 
1303M32G12, installed in drainless fuel manifold assemblies (introduced 
by GE Aircraft Engines (GEAE) Service Bulletins (SB) CF6-80C2 S/B 73-
0253 and CF6-80E1 S/B 73-0026). This AD requires removing the loop 
clamps that hold the fuel manifold to the compressor rear frame (CRF) 
damper brackets, inspecting the fuel manifold for wear at each clamp

[[Page 8162]]

location, and replacing the clamps with new, zero-time parts. This AD 
also requires revising the Airworthiness Limitations Section (ALS) of 
the Instructions for Continued Airworthiness (ICA) and air carrier's 
Continuous Airworthiness Maintenance Programs (CAMP) to require 
repetitive fuel manifold inspection and loop clamp replacement. This AD 
results from reports of fuel leaks during engine operation. We are 
issuing this AD to prevent fuel leaks that could result in an under-
cowl fire and damage to the airplane.

DATES: This AD becomes effective March 31, 2009.

ADDRESSES: The Docket Operations office is located at Docket Management 
Facility, U.S. Department of Transportation, 1200 New Jersey Avenue, 
SE., West Building Ground Floor, Room W12-140, Washington, DC 20590-
0001.

FOR FURTHER INFORMATION CONTACT: Robert Green, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; e-mail: 
Robert.green@faa.gov; telephone (781) 238-7754; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39 
with a proposed AD. The proposed AD applies to GE CF6-80C2 and CF6-80E1 
series turbofan engines with fuel manifolds P/Ns 1303M31G12 and 
1303M32G12 installed in drainless fuel manifold assemblies. These 
drainless fuel manifold assemblies were introduced by GEAE SBs CF6-80C2 
S/B 73-0253 and CF6-80E1 S/B 73-0026. We published the proposed AD in 
the Federal Register on September 7, 2007 (72 FR 51388). That action 
proposed to require removing and discarding the loop clamps that 
assemble the fuel manifolds to the CRF damper brackets, inspecting the 
fuel manifolds for wear at each clamp location, and replacing the 
clamps. That action also proposed to require revising the ICA ALS and 
air carrier's CAMP to require repetitive fuel manifold inspection and 
loop clamp replacement during each inspection.

Examining the AD Docket

    You may examine the AD docket on the Internet at https://
www.regulations.gov; or in person at the Docket Operations office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this AD, the regulatory evaluation, 
any comments received, and other information. The street address for 
the Docket Operations office (telephone (800) 647-5527) is provided in 
the ADDRESSES section. Comments will be available in the AD docket 
shortly after receipt.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments received.

Request To Clarify Inspection Requirements

    GE and two air carriers request that we clarify that the AD 
inspection requirements are specific to the drainless fuel manifold 
configuration, which was introduced by GEAE SB CF6-80C2 S/B 73-0253 (-
80C2) and SB CF6-80E1 S/B 73-0026 (-80E1).
    We agree. We changed the AD to clarify the applicability and 
inspection requirements.

Request for a Phase-in Period

    FedEx Express requests that we add a phase-in period for engines 
that might not have been part of a repetitive inspection program before 
the effective date of the AD. The commenter states that these engines 
would immediately fall out of compliance with the AD if they exceed the 
7,500 flight-hour time-since-new (TSN) threshold for new, zero-time 
loop clamps, assuming the loop clamps were installed at the last shop 
visit. The commenter states that their fleet is almost entirely 
configured with drained manifold assemblies. They have not experienced 
any significant wear, and likely will have several engines exceeding 
the specified flight-hour life limit in the AD.
    We partially agree. As we stated in the first comment response, 
this AD applies only to drainless manifold assemblies, so that portion 
of FedEx's comment is not relevant to this AD. The need for a phase-in 
period is valid. We received another comment on that point and we 
changed the AD to accommodate the concerns. That discussion follows 
below.

Incorrect Service Bulletin Reference

    GE, the Air Transport Association, Boeing Commercial Airplanes, and 
seven carriers point out that the proposed AD incorrectly referenced SB 
GEAE CF6-80C2 S/B 73-0226, for the manifold inspection. The appropriate 
SB is CF6-80C2 S/B 73-0326.
    We agree. We changed the reference in the AD.

Comment That Clamp Wear Is Also Applicable to Drained Fuel Manifold 
Assemblies

    Air New Zealand Ltd and KLM Royal Dutch Airlines comment that the 
clamp wear problem is also applicable to fuel manifolds P/N 1303M31G10 
and P/N 1303M32G10 installed in the drained fuel manifold assembly, 
pre-SB CF6-80C2 S/B 73-0253 configuration.
    We do not agree. We are aware of only one leak found from loop 
clamp wear on a drained fuel manifold assembly, which was on a CF6-80C2 
series turbofan engine. Considering the service history of the drained 
fuel manifold assembly, a mandatory inspection is not warranted at this 
time. We did not change the AD.

Request To Apply the Re-Inspection Interval to Engines That Have Had 
New, Zero-Time Loop Clamps Installed On-Wing

    Air New Zealand Ltd and KLM Royal Dutch Airlines note that the 
proposed AD requires a 7,500 flight-hour re-inspection interval for 
first-run engines and engines that have new, zero-time loop clamps 
installed at last shop visit. The commenters request that we apply the 
same re-inspection interval to engines that have had new, zero-time 
loop clamps installed on-wing. Air New Zealand states that they have 
been replacing loop clamps with new, zero-time loop clamps when they 
perform on-wing inspections of the fuel manifolds.
    We agree. We changed the AD to include on-wing replacement of loop 
clamps.

Request for Credit for Installing Loop Clamps On-Wing

    All Nippon Airways requests that the AD initial inspection state 
that the 7,500 re-inspection interval for first-run engines or engines 
that have had new, zero-time loop clamps previously installed, apply 
regardless of previous inspection per GEAE SB CF6-80C2 S/B 73-0326 or 
SB CF6-80E1 S/B 73-0061. The commenter points out that the proposed AD 
does not recognize that operators were replacing the loop clamps on-
wing.
    We agree. We changed the AD to clarify that the re-inspection 
requirement is not preempted by compliance with existing SB inspection 
recommendations.

Request To Consider Using Room Temperature Vulcanizing (RTV) Rubber 
Compound

    Air India requests that we consider allowing the use of red, room-
temperature vulcanizing (RTV) rubber

[[Page 8163]]

compound (Specification A15F6B6; RTV 106; MIL-846106), between the loop 
clamps and fuel manifold when the loop clamps are replaced with new, 
zero-time parts at inspection. Air India states that they have applied 
RTV rubber compound on the inner diameter of loop clamps where they 
have observed wear on other engine tubing. GE previously recommended 
using RTV rubber compound on the low-pressure turbine cooling 
manifolds, and Air India now uses it at other locations.
    We do not agree. We have no data or experience to justify use of 
RTV rubber compound in this application. We did not change the AD.

Recommendation To Use Fiberglass Tape

    The Air Transport Association and American Airlines recommend that 
we revise the proposed AD to allow the optional use of fiberglass tape 
on the fuel manifolds under the loop clamps. The commenters state that 
using the tape will eliminate the wear and reduce the effects of 
vibration by improving the fit of the clamps on the fuel manifolds. 
American Airlines states that they have been installing the fiberglass 
tape on their fuel manifolds at the time of inspection and loop clamp 
replacement since the beginning of their program. They believe the tape 
is essential to preventing fuel manifold wear.
    We do not agree. We reviewed the data GE provided and concluded 
that using fiberglass tape may contribute to the fuel manifold wear. GE 
has also stated that they no longer recommend fiberglass tape for this 
application. We did not change the AD.

Request for a Unique Compliance Recommendation and Re-Inspection 
Interval

    Lufthansa Technik AG and a private citizen request a unique 
compliance recommendation and re-inspection interval for engines that 
had been previously inspected and or reassembled with new, zero-time 
loop clamps, with fiberglass tape between the loop clamps and fuel 
manifolds. Lufthansa Technik AG states that they have observed less 
wear when using the fiberglass tape.
    We do not agree. As previously noted, GE has stated that they no 
longer recommend fiberglass tape for this application. We did not 
change the AD.

Request To Not Remove Fiberglass Tape

    Lufthansa Technik AG and GE Aviation request that we revise the 
fuel manifold inspection to not require removal of tape between the 
loop clamp and fuel manifold, unless wear is observed on the tape. GEAE 
SB CF6-80C2 S/B 73-0326, dated March 5, 2003, introduced the option of 
installing fiberglass tape on CF6-80C2 series engines. Lufthansa 
Technik AG states that if there is no wear found on the tape, then 
there will be no wear on the fuel manifold. Removing and replacing all 
tape at the time of inspection will add additional unnecessary work-
hours to the inspection.
    We do not agree. As noted earlier, the tape may contribute to the 
wear, and GE no longer recommends fiberglass tape for this application. 
GE's comment was in anticipation of a future design change with Teflon 
tape between the loop clamps and fuel manifolds. We did not change the 
AD.

Request That the AD Recognize the Use of Teflon Tape

    GE Aviation and five air carriers request that the AD recognize the 
use of Teflon tape between new, zero-time loop clamps and fuel 
manifolds. The commenters request that we allow these engines to 
continue in service until the next inspection, without limit or 
penalty. The air carriers state that they have already been installing 
Teflon tape between new, zero-time loop clamps and fuel manifolds.
    We do not agree. We have no data or experience to make a 
determination for reducing or extending the inspection and loop clamp 
replacement intervals because of installing Teflon tape between the 
loop clamps and fuel manifolds. GE has certified new fuel manifolds 
with PTFE tape installed at the loop clamp locations. These parts have 
the same inspection and loop clamp replacement requirements as the 
original parts. We did not change this AD.

Request for Clarification of Compliance Inspection Schedule

    Lufthansa Technik AG and Virgin Atlantic Airways request that we 
clarify whether a poorly fitting loop clamp, with or without tape, 
would compromise the compliance inspection schedule in the AD.
    We respond that it would not compromise the compliance inspection 
schedule in the AD. We concluded that replacing the loop clamps every 
7,500 flight-hours (FH) was appropriate based on a GE Weibull analysis 
of the engine fleet, the first five fuel leak failures, and the accrued 
operation of 1,289 engines that had no leaks. The data was from first-
run engines, which encompasses typical production loop clamp stack-up 
variations without tape. None of the subsequent leaks and failures 
occurred with less time than the proposed AD inspection compliance 
interval of 7,500 FH. We did not change the AD.

Request To Specify Flight Hours Time-Since-Last-Inspection or Flight 
Hours Time-Since-Last-Shop Visit

    Japan Airlines International requests that for clarification, the 
initial inspection schedule should specify FH time-since-last-
inspection or FH time-since-last-shop visit as of the issue date of the 
AD.
    We partially agree. The initial inspection schedule is defined 
relative to the last inspection or replacement of the loop clamps with 
new clamps. However, for those engines that exceed the 1,750 and 4,500 
FH thresholds, the determination is made as of the effective date of 
the AD. We changed the AD to clarify this.

Request To Offset the Initial Inspection Schedule

    Japan Airlines International requests that we offset the initial 
inspection schedule to accommodate the scheduling of maintenance.
    We do not agree. The time for scheduling maintenance varies among 
operators. Defining a generic inspection threshold to accommodate this 
variation would introduce risk that the inspection schedule would be 
ambiguous. We did not change the AD.

Propose an Additional Inspection Category

    Japan Airlines International proposes an additional inspection 
category for operators inspecting the manifolds at intervals longer 
than the GE-recommended 4,500 FH interval. The commenter proposes that 
in these cases, operators would initially replace the loop clamps and 
inspect the fuel manifolds using their existing inspection schedule or 
within 4 months, whichever occurs first. The commenter states that they 
currently inspect affected fuel manifolds at 6,000 FH intervals, and 
based on the wording in the proposed AD, engines would be immediately 
in violation of the inspection requirements once the AD is effective.
    We partially agree. The commenter points out the need to include a 
transitional period for operators who are inspecting the fuel manifolds 
at intervals longer than the earlier GE inspection SB recommendation, 
which is engines operating with more than 4,500 FH time-since-last-
inspection or time-since-last-shop visit. We changed the AD to include 
a four-month transition period, to bring these engines into compliance.

[[Page 8164]]

Request To Permit Alternate Methods of Measuring

    Japan Airlines International and GE Aviation request that we permit 
alternate methods of measuring the depth of wear in fuel manifolds, 
such as ultrasonic wall thickness measurement. The commenters note that 
the proposed AD requires using a pinpoint micrometer to measure depth 
of wear. Because of limited access at the top of the installed engine, 
the commenter states it is not possible to use a pinpoint micrometer.
    We partially agree. GE does not have a procedure for ultrasonic 
inspections of the fuel manifolds for depth of wear. However, we agree 
that equivalent measuring techniques are acceptable. We eliminated the 
requirement to use a pinpoint micrometer.

Request for Clarification of the Use of Part Manufacturer Approval 
(PMA) Loop Clamps

    Japan Airlines International requests clarification on the use of 
PMA loop clamps. The commenter asks if the proposed AD also applies to 
PMA loop clamps, part number VL1039GE2-10.
    Yes, the AD applies to PMA loop clamps. They are also susceptible 
to deteriorating and causing fuel leaks. We changed the AD to include a 
reference to PMA loop clamps.

Question on Compliance Time Selection

    KLM Royal Dutch Airlines questions the selection of the proposed AD 
compliance time of 1,750 FH time-since-last-inspection (TSLI). The 
commenter asks why we did not base the compliance recommendation on the 
low-time TSLI fuel manifold leak event for an engine with used loop 
clamps, which is 350 FH. The commenter also asks why we did not use the 
next lowest-time fuel manifold leak event, which is 2,000 FH TSLI. The 
commenter cites data presented by GE at the CF6 Technical Symposium on 
May 9 through May 10, 2007.
    We do not agree. Since 2005, the fuel manifold leak failure rate 
has increased. There were four leak events in 2006, six in 2007, and 
six to date in 2008. Thirteen of the events are known to have occurred 
before the GE-recommended 4,500 FH re-inspection interval. The average 
TSLI for the thirteen failures is 2,250 FH. The 350 FH leak is a low-
time event relative to the other failures and is believed to be unique. 
The 1,750 FH TSLI compliance requirement was based on the next-lowest 
TSLI leak event at the time, which was after the GE CF6 Technical 
Symposium. We did not change the AD.

Question on Why the Compliance Time Is Extended

    KLM Royal Dutch Airlines questions why the proposed AD extends the 
1,750 FH TSLI compliance time to 4,500 FH TSLI or 4 months after the 
effective date of the AD, for engines with used clamps or clamps of 
unknown heritage that have already accumulated more than 1,750 FH. The 
commenter is concerned that this 4-month compliance period will 
increase the probability of a fuel manifold leak event.
    We do not agree. The proposed inspection and loop clamp replacement 
schedule for engines that already exceed the 1,750 FH threshold is an 
effort to transition the engine fleet to new loop clamps within a 
reasonable period of time. This will be achieved either through the 
original GE-recommended 4,500 FH schedule or within 4 months, whichever 
comes first. We did not change the AD.

Question on GE's Risk Assessment

    KLM Royal Dutch Airlines questions why we disregarded GE's risk 
assessment that justified the 4,500 FH inspection interval.
    We did because GE's risk assessment predicted fuel manifold leak 
events within the 4,500 FH inspection intervals. As previously noted, 
the leaking fuel could ignite resulting in an under-cowl fire and 
damage to the airplane, which is unacceptable.

Recommendation That We Eliminate Revising the Air Carrier's Approved 
CAMP and ALS of Chapter 5

    The Air Transport Association and U.S. Airways recommend that we 
eliminate the requirement to revise the air carrier's approved CAMP and 
ALS of Chapter 5 in the CF6-80C2 and CF6-80E1 Instructions for 
Continued Airworthiness (ICA) from the proposed AD. The commenters 
state that GE has indicated it is developing new-design fuel manifolds 
to eliminate the repetitive maintenance required by this AD.
    We do not agree. The AD requires GE to revise the ALS of the ICAs, 
and air carriers to revise their CAMP, to specify the repetitive 
inspections and loop clamp replacements for the drainless fuel manifold 
assemblies with fuel manifold P/N 1303M31G12 and P/N 1303M32G12. The AD 
would not be applicable to a new design. We did not change the AD.

Request To Change the Proposed AD Discussion

    GE Aviation requests that we change the proposed AD Discussion to 
state that abrasive dirt and debris collecting between the worn loop 
clamps and fuel manifolds can result in fuel manifold wear with loop 
clamps that appear serviceable.
    We partially agree. The deterioration of the loop clamp and 
possible accumulation of dirt and debris between the loop clamp cushion 
and fuel manifold might contribute to fuel manifold wear, but if so, it 
is a secondary factor. The root cause of the fuel manifold wear is fuel 
manifold vibration during engine operation. We did not change the AD.

Request To Consider the Probability of an Under-Cowl Fire

    GE Aviation requests that we consider a longer inspection/
replacement interval, and requests that we consider the probability of 
an under-cowl engine fire if we use 4,500 flight-hours instead. GE 
Aviation requests that we consider an intermediate compliance time that 
is supportable by industry if the 4,500 FH does not sufficiently reduce 
the risk of an under-cowl fire. GE states that our proposed 1,750 FH 
TSLI interval will reduce the average time between inspections from 15 
months to less than 6 months, and increase the number of engines that 
will need to be inspected per week during the transition by a factor of 
2.5. This will severely burden industry's maintenance capacity. GE also 
states that the additional work required to bring engines that already 
exceed the 1,750 FH into compliance, during the 4-month grace period, 
will make the burden worse.
    We partially agree. The commenter did not consider first-run 
engines or engines that have already had new, zero-time loop clamps 
installed during either last shop visit or an earlier in-service 
inspection. We also note that despite the GE 4,500 FH TSLI SB 
recommendation, one fuel leak event occurred in 2005, four occurred in 
2006, and six fuel leak events occurred in 2007. Nine of these 11 
events occurred within the recommended 4,500 FH interval. We agree that 
the lack of a calendar compliance period with the 1,750 FH threshold 
could result in an immediate maintenance scheduling problem and we 
changed the AD to include the 4-month compliance period with the 1,750 
FH threshold to facilitate the transition.

Request To Revise Costs of Compliance

    Japan Airlines International and GE Aviation request that we revise 
the Costs of Compliance. GE Aviation estimates that 2 work-hours are 
required to inspect the loop clamps and fuel manifolds. Japan Airlines 
estimates that

[[Page 8165]]

based on their experience, 8 work-hours are required for the 
inspections.
    We do not agree. In recognizing the possible work-hour variations 
from operator to operator, we believe that 4 work-hours is a valid 
average. We did not change the AD.

Conclusion

    We have carefully reviewed the available data, including the 
comments received, and determined that air safety and the public 
interest require adopting the AD with the changes described previously. 
We have determined that these changes will neither increase the 
economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

    We estimate that this AD will affect 350 CF6-80C2 series turbofan 
engines installed on airplanes of U.S. registry. We also estimate that 
it will take about 4 work-hours per engine to perform the actions, and 
that the average labor rate is $80 per work-hour. Required parts will 
cost about $162 per engine. Based on these figures, we estimate the 
total cost of the AD to U.S. operators for a once-through-the-fleet 
manifold visual inspection and loop clamp replacement to be $168,700.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, Section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We have determined that this AD will not have federalism 
implications under Executive Order 13132. This AD will not have a 
substantial direct effect 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.
    For the reasons discussed above, I certify that this AD:
    (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.
    We prepared a summary of the costs to comply with this AD and 
placed it in the AD Docket. You may get a copy of this summary at the 
address listed under ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the Federal Aviation Administration amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

2009-05-02 General Electric Company: Amendment 39-15826. Docket No. 
FAA-2007-28413; Directorate Identifier 2007-NE-25-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective March 
31, 2009.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to:
    (1) General Electric (GE) CF6-80C2A1, -80C2A2, -80C2A3, -80C2A5, 
-80C2A8, -80C2A5F, -80C2B1, -80C2B2, -80C2B4, -80C2B6, -80C2B1F, -
80C2B1F1, -80C2B1F2, -80C2B2F, -80C2B3F, -80C2B4F, -80C2B5F, -
80C2B6F, -80C2B6FA, -80C2B7F, -80C2B8F, -80C2D1F, -80C2L1F, -80C2K1F 
turbofan engine models with fuel manifold part numbers (P/Ns) 
1303M31G12 and 1303M32G12, installed in drainless fuel manifold 
assemblies (introduced by GE Aircraft Engines (GEAE) Service 
Bulletin (SB) CF6-80C2 S/B 73-0253). These engines are installed on, 
but not limited to, Boeing 747, 767, MD11, and Airbus A300-600 and 
A310 airplanes.
    (2) This AD also applies to GE CF6-80E1A1, -80E1A2, -80E1A3, -
80E1A4, -80E1A4/B turbofan engine models with fuel manifold P/Ns 
1303M31G12 and 1303M32G12, installed in drainless fuel manifold 
assemblies (introduced by GEAE SB CF6-80E1 S/B 73-0026). These 
engines are installed on Airbus A330 airplanes.

Unsafe Condition

    (d) This AD results from reports of fuel leaks during engine 
operation. We are issuing this AD to prevent fuel leaks that could 
result in an under-cowl fire and damage to the airplane.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified unless the 
actions have already been done.

Removal and Replacement of Loop Clamps and Fuel Manifold Inspection 
Compliance Times

    (f) Using Table 1 of this AD, Schedule for Inspections and 
Replacements, accomplish the following actions in the intervals 
indicated in the table: remove and discard all loop clamps, P/N 
J1220G10, or part manufacturer approval (PMA) equivalent, that hold 
the fuel manifold to the compressor rear frame (CRF) friction damper 
brackets. Inspect the fuel manifold for wear at each clamp location 
as specified in paragraphs (g) and (h) of this AD. Replace the 
discarded loop clamps with new, zero-time clamps.

           Table 1--Schedule for Inspections and Replacements
------------------------------------------------------------------------
                                       Then replace clamps and inspect
                If:                                within:
------------------------------------------------------------------------
(1) The engine was previously        1,750 flight hours (FH) time-since-
 inspected using GEAE SB CF6-80C2 S/  last-inspection (TSLI) or within 4
 B 73-0326, dated March 5, 2003,      months after the effective date of
 for CF6-80C2 engines; or GEAE SB     this AD.
 CF6-80E1 S/B 73-0061, dated April
 14, 2003, for CF6-80E1 engines.
(2) Used loop clamps or clamps of    1,750 FH time-since-last-shop-visit
 unknown heritage were installed at   or within 4 months after the
 last shop visit.                     effective date of this AD.

[[Page 8166]]

 
(3) The engine is a first-run        7,500 FH time-since-new or since
 engine or is an engine with zero-    zero-time, new loop clamps were
 time, new loop clamps previously     installed (regardless if
 installed on-wing or at shop visit.  previously inspected per GEAE SB
                                      CF6-80C2 S/B 73-0326 or GEAE SB
                                      CF6-80E1 S/B 73-0061).
(4) The engine has already exceeded  4,500 FH TSLI, or 4 months after
 the 1,750 FH initial inspection      the effective date of this AD,
 threshold on the effective date of   whichever occurs first.
 this AD, but has fewer than 4,500
 flight hours TSLI.
(5) The engine has already exceeded  4 months after the effective date
 the 4,500 FH initial inspection      of this AD.
 threshold on the effective date of
 this AD.
------------------------------------------------------------------------

Inspection of Fuel Manifold P/Ns 1303M31G12 and 1303M32G12

    (g) Remove any tape at any clamp location. Visually inspect the 
full circumference of the manifold for wear at each clamp location. 
If any wear is found, follow paragraph (h) of this AD.
    (h) When the fuel manifold shows any signs of wear, determine 
the depth of the wear as follows:
    (1) Measure the outside diameter of the tube adjacent to the 
worn area.
    (2) Measure the worn area at the smallest diameter.
    (3) Subtract the measurement of the worn tube diameter from the 
unworn diameter measurement. Allowable wear is 0.0035 inch.
    (4) Replace fuel manifolds with wear greater than 0.010 inch 
before further flight.
    (5) Replace fuel manifolds with wear greater than 0.0035 inch 
but less than 0.010 inch, within 50 flight cycles.

Revise Air Carrier's Continuous Airworthiness Maintenance Program 
(CAMP) and Airworthiness Limitation Section (ALS)

    (i) Within 30 days of the effective date of this AD, revise the 
air carrier's approved CAMP and Instructions for Continued 
Airworthiness (ICA) Chapter 5, Airworthiness Limitation Section for 
the CF6-80C2 and CF6-80E1 series engines to require:
    (1) Repetitive inspections of fuel manifolds, P/Ns 1303M31G12 
and 1303M32G12, installed in drainless fuel manifold assemblies 
introduced by CF6-80C2 S/B 73-0253 and CF6-80E1 S/B 73-0026, as 
detailed in paragraphs (g) and (h) of this AD, at 7,500 FH 
intervals.
    (2) Mandatory removal of all loop clamps that hold the fuel 
manifold, P/Ns 1303M31G12 and 1303M32G12, to the CRF damper 
brackets, at each inspection.
    (3) Replacement of all loop clamps with new, zero-time loop 
clamps, at each inspection.

Alternative Methods of Compliance

    (j) The Manager, Engine Certification Office, has the authority 
to approve alternative methods of compliance for this AD if 
requested using the procedures found in 14 CFR 39.19.

Related Information

    (k) GEAE SB CF6-80C2 S/B 73-0326, dated March 5, 2003, and GEAE 
SB CF6-80E1 S/B 73-0061, dated April 14, 2003; and the following GE 
engine manuals pertain to the subject of this AD:
    (1) CF6-80C2 Engine Manual GEK 92451.
    (2) CF6-80C2L1F Engine Manual GEK 112213.
    (3) CF6-80C2K1F Engine Manual GEK 112721.
    (4) CF6-80E1 Engine Manual GEK 99376.
    (l) Contact General Electric Company via Lockheed Martin 
Technology Services, 10525 Chester Road, Suite C, Cincinnati, Ohio 
45215; telephone (513) 672-8400; fax (513) 672-8422, for the service 
information identified in this AD.
    (m) Contact Robert Green, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
Robert.green@faa.gov; telephone (781) 238-7754; fax (781) 238-7199, 
for more information about this AD.

    Issued in Burlington, Massachusetts, on February 17, 2009.
Thomas A. Boudreau,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
 [FR Doc. E9-3868 Filed 2-23-09; 8:45 am]
BILLING CODE 4910-13-P

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.