Federal Aviation Administration (FAA), Department of Transportation (DOT).
The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 777-200, -300, and -300ER series airplanes. This AD requires a one-time inspection of the first bonding jumper aft of the bulkhead fitting to detect damage or failure and to determine the mechanical integrity of its electrical bonding path, and repair if necessary; measuring the bonding resistance between the fitting for the fuel feed tube and the front spar in the left and right main fuel tanks, and repairing the bonding if necessary; and applying additional sealant to completely cover the bulkhead fittings inside the fuel tanks. This AD results from fuel system reviews conducted by the manufacturer. We are issuing this AD to prevent arcing or sparking during a lightning strike at the interface between the bulkhead fittings of the engine fuel feed tube and the front spar inside the fuel tank. This arcing or sparking could provide a potential ignition source inside the fuel tank, Start Printed Page 34809which, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of the airplane.
This AD becomes effective July 21, 2006.
The Director of the Federal Register approved the incorporation by reference of a certain publication listed in the AD as of July 21, 2006.
You may examine the AD docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC.
Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207, for service information identified in this AD.Start Further Info
FOR FURTHER INFORMATION CONTACT:
Margaret Langsted, Aerospace Engineer, Propulsion Branch, ANM-140S, Seattle Aircraft Certification Office, FAA, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 917-6500; fax (425) 917-6590.End Further Info End Preamble Start Supplemental Information
Examining the Docket
You may examine the airworthiness directive (AD) docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647-5227) is located on the plaza level of the Nassif Building at the street address stated in the ADDRESSES section.
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to certain Boeing Model 777 airplanes. That NPRM was published in the Federal Register on March 21, 2006 (71 FR 14126). That NPRM proposed to require a one-time inspection of the first bonding jumper aft of the bulkhead fitting to detect damage or failure and to determine the mechanical integrity of its electrical bonding path, and repair if necessary; measuring the bonding resistance between the fitting for the fuel feed tube and the front spar in the left and right main fuel tanks, and repairing the bonding if necessary; and applying additional sealant to completely cover the bulkhead fittings inside the fuel tanks.
We provided the public the opportunity to participate in the development of this AD. We have considered the comments received.
Support for the NPRM
Boeing concurs with the NPRM.
Request To Revise the Service Bulletin
Japan Airlines (JAL) suggests that Boeing should revise Boeing Special Attention Service Bulletin 777-28-0044, Revision 1, dated December 20, 2005, to incorporate the repair instructions for the bonding path rather than having them separate from the service bulletin. (This service bulletin was referenced as the appropriate source of service information for accomplishing the actions in the NPRM.) JAL states that it would be simpler if the AD referred to the service bulletin for the whole work instructions, including all repair procedures.
We partially agree. We agree with JAL that having all repair procedures in one place can be simpler for operators. We do not agree that Boeing should revise its service bulletin for this reason, nor can we request a manufacturer to revise a service bulletin to make addressing an unsafe condition more convenient. Waiting to include a revised service bulletin in this action would delay addressing an unsafe condition. In addition, manufacturers' service information often refers to procedures in various maintenance manuals for a number of reasons (e.g., to keep procedures in the service bulletin from becoming too cumbersome, or because the procedure is an industry best practice). In this case, the referenced service bulletin refers to Chapter 28-00-00 of the Boeing 777 Aircraft Maintenance Manual (AMM) for doing the general visual inspection of the first bonding jumper aft of the bulkhead fitting to detect damage or failure and to determine the mechanical integrity of its electrical bonding path. We assume some of JAL's issue stems from the statement in paragraph (f)(1) of the NPRM that these conditions must be repaired according to a method we approve, and that Chapter 28-00-00 of the Boeing 777 AMM is one approved method. We included that statement in paragraph (f)(1) because although the service bulletin implies repair for the bonding path in accordance with the AMM chapter, the statement in the service bulletin is not explicit and could be confusing. We have not changed the final rule in this regard.
Request To Revise Cost Estimate
Air Transport Association (ATA), on behalf of American Airlines, requests that we revise the cost estimate. American Airlines quotes an “AD memo” that reads “FAA estimates that 46 airplanes of U.S. registry would be affected by this rulemaking.” American Airlines points out that it has 45 affected airplanes, and that there are three other U.S. operators that also have affected airplanes. American Airlines also does not concur with the statement in the NPRM that the cost of the proposed actions would be $640 per airplane for eight hours of work. Although American Airlines understands that the FAA does not consider access time when calculating the cost to comply with an AD, American Airlines believes it is important to note that this inspection and sealant application requires complete draining and venting of the fuel tanks, which alone could take eight hours. In total, American Airlines estimates the inspection and sealant application will require approximately 48 work hours per airplane at a cost of $202,586.
We partially agree with the commenters. We agree that there are more than 45 airplanes of U.S. registry affected by the actions in the NPRM. We are not familiar with an “AD memo,” which could have been a summary of the NPRM initiated by another source. The number of affected airplanes listed in the NPRM is 131 rather than 45. We have revised the “Costs of Compliance” paragraph to reflect this information.
We do not agree with revising the number of work hours in the cost estimate. As American Airlines points out, we do not consider access time when calculating the cost of an AD. The cost information below describes only the direct costs of the specific actions required by this AD. Based on the best data available, the manufacturer provided the number of work hours (8) necessary to do the required actions. This number represents the time necessary to perform only the actions actually required by this AD. We recognize that, in doing the actions required by an AD, operators may incur incidental costs in addition to the direct costs. The cost analysis in AD rulemaking actions excludes the costs of the time required to gain access and close up, as American points out, but it also excludes other incidental costs such as the time necessary for planning, or time for other administrative actions. All of these costs may vary significantly among operators and are almost impossible to calculate. We have not changed the final rule in this regard.
Explanation of Change in Applicability
We have revised the applicability of this final rule to match the most current Start Printed Page 34810type certificate data sheet for the affected airplanes.
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 change described previously. We have determined that this change will neither increase the economic burden on any operator nor increase the scope of the AD.
Costs of Compliance
There are about 497 airplanes of the affected design in the worldwide fleet. This AD affects about 131 airplanes of U.S. registry. The actions take about 8 work hours per airplane, at an average labor rate of $80 per work hour. Based on these figures, the estimated cost of the AD for U.S. operators is $83,840, or $640 per airplane.
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.
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 regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.Start List of Subjects
List of Subjects in 14 CFR Part 39End List of Subjects
Adoption of the AmendmentStart Amendment Part
Accordingly, under the authority delegated to me by the Administrator, the FAA amendsEnd Amendment Part Start Part
PART 39—AIRWORTHINESS DIRECTIVESEnd Part Start Amendment Part
1. The authority citation for part 39 continues to read as follows:End Amendment Part
2. The Federal Aviation Administration (FAA) amends § 39.13 by adding the following new airworthiness directive (AD):End Amendment Part
2006-12-26 Boeing: Amendment 39-14652. Docket No. FAA-2006-24173; Directorate Identifier 2005-NM-262-AD.
(a) This AD becomes effective July 21, 2006.
(c) This AD applies to Boeing Model 777-200, -300, and -300ER series airplanes, certificated in any category; as identified in Boeing Special Attention Service Bulletin 777-28-0044, Revision 1, dated December 20, 2005.
(d) This AD results from fuel system reviews conducted by the manufacturer. We are issuing this AD to prevent arcing or sparking during a lightning strike at the interface between the bulkhead fittings of the engine fuel feed tube and the front spar inside the fuel tank. This arcing or sparking could provide a potential ignition source inside the fuel tank, which, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of the airplane.
(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.
Inspection and Corrective Actions
(f) Within 60 months after the effective date of this AD, do the actions specified in paragraphs (f)(1), (f)(2), and (f)(3) of this AD for the bulkhead fittings of the engine fuel feed tube for the left and right main fuel tanks. Do all actions in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-28-0044, Revision 1, dated December 20, 2005.
(1) Do a general visual inspection of the first bonding jumper aft of the bulkhead fitting to detect damage or failure and to determine the mechanical integrity of its electrical bonding path. If any damage or failure is found during this inspection or if the mechanical integrity of the bonding path is compromised: Before further flight, repair according to a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA. Chapter 28-00-00 of the Boeing 777 Aircraft Maintenance Manual is one approved method.
(2) Measure the bonding resistance between the fitting for the fuel feed tube and the front spar in the left main fuel tank. If the bonding resistance exceeds 0.001 ohm: Before further flight, repair the bonding in accordance with the service bulletin.
(3) Apply additional sealant to completely cover the bulkhead fitting inside the fuel tank.
Actions Accomplished in Accordance With Previous Revision of Service Bulletin
(g) Actions done before the effective date of this AD in accordance with Boeing Special Attention Service bulletin 777-28-0044, dated February 3, 2005, are acceptable for compliance with the requirements of paragraph (f) of this AD.
Alternative Methods of Compliance (AMOCs)
(h)(1) The Manager, Seattle ACO, FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.
(2) Before using any AMOC approved in accordance with § 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.
Material Incorporated by Reference
(i) You must use Boeing Special Attention Service Bulletin 777-28-0044, Revision 1, dated December 20, 2005, to perform the actions that are required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference of this document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207, for a copy of this service information. You may review copies at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street, SW., Room PL-401, Nassif Building, Washington, DC; on the Internet at http://dms.dot.gov; or at the National Archives and Records Administration (NARA). For information on the availability of this material at the NARA, call (202) 741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.Start Signature
Issued in Renton, Washington, on June 8, 2006.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 06-5428 Filed 6-15-06; 8:45 am]
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