Airworthiness Directives; Boeing Model 777 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Final rule.

SUMMARY:

This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 777 series airplanes, that requires replacing four socket contacts on the four boost pumps of the main fuel tanks with new, high-quality gold-plated contacts, and sealing the backshell of the connector with potting compound. This action is necessary to prevent a possible source of ignition in a flammable leakage zone, which could result in an undetected and uncontrollable fire in the wheel well or wing trailing edge, and a possible fuel tank explosion. This action is intended to address the identified unsafe condition.

DATES:

Effective October 19, 2004.

The incorporation by reference of a certain publication listed in the regulations is approved by the Director of the Federal Register as of October 19, 2004.

ADDRESSES:

The service information referenced in this AD may be obtained from Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207. This information may be examined at the Federal Aviation Administration (FAA), Transport Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or 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: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

FOR FURTHER INFORMATION CONTACT:

Margaret Langsted, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington; telephone (425) 917-6500; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain Boeing Model 777 series airplanes was published in the Federal Register on December 8, 2003 (68 FR 68311). That action proposed to require replacing four socket contacts on the four boost pumps of the main fuel tanks with new, high-quality gold-plated contacts, and sealing the backshell of the connector with potting compound.

Comments

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

Support for Notice of Proposed Rulemaking (NPRM)

Two commenters generally support the intent of the NPRM.

Request To Reference Latest Service Bulletin

One of the two commenters requests that the NPRM be revised to refer to Boeing Special Attention Service Bulletin 777-28-0028, Revision 1 or latest revision. The commenter notes that the NPRM refers to Boeing Special Attention Service Bulletin 777-28-0028, dated October 24, 2002, as the appropriate source of service information for the proposed actions. Based on Boeing Service Bulletin Information Notice 777-28-0028 IN 01, dated February 13, 2003, the commenter states that the airplane manufacturer is planning to revise the subject service bulletin.

The FAA agrees with the commenter to refer to Revision 1 of Boeing Service Bulletin 777-28-0028, dated July 15, 2004. Since the issuance of the NPRM, we have reviewed Revision 1. Revision 1 is essentially identical to the original issue of the service bulletin, which is referred to as the appropriate source of service information in the NPRM. No more work is necessary on airplanes changed as shown in the original issue. The only relevant changes are a revised listing of current operators of affected airplanes. Revision 1 incorrectly refers to June 06, 2002, as the date of issuance of the original issue of the service bulletin; the correct date is October 24, 2002. We have revised the final rule to refer to Revision 1 as the appropriate source of service information for the required actions and to include a new paragraph that gives operators credit for accomplishing the required actions before the effective date of this AD in accordance with original issue.

Request To Revise Work Hour Estimate

One commenter states that the labor estimate of 4 work hours in the Cost Impact section of the NPRM is unrealistic. The commenter states that there are four main tank boost pump positions, and that four work hours per airplane equates to one work hour per pump position. The commenter also states that the proposed replacement is comprised of the following tasks: preparing the airplane for rework, gaining access to each pump connector, re-terminating four sockets per connector, potting in connector sealant, etc. Excluding the sealant cure time, the commenter estimates that labor work hours are approximately three hours per pump position or 12 work hours per airplane.

From this comment, we infer that the commenter is requesting that the work hour estimate in the Cost Impact section of the NPRM be revised. We partially agree. We do agree that the work hour estimate can be increased, but only somewhat. The cost impact information, below, describes only the “direct” costs of the specific actions required by this AD. The number of work hours necessary to accomplish the required actions represents the time necessary to perform the replacement required by this AD. We recognize that, in accomplishing the requirements of any AD, operators may incur “incidental” costs in addition to the “direct” costs. The cost analysis in AD rulemaking actions, however, typically does not include incidental costs, such as the time required to gain access and close up; planning time; or time necessitated by other administrative actions. Because incidental costs may vary significantly from operator to operator, they are almost impossible to calculate. Therefore, based on the information supplied by the commenter, we now recognize that it will take approximately 6 work hours per airplane to accomplish the required actions. We have revised the Cost Impact section of the final rule accordingly.

Conclusion

After careful review of the available data, including the comments noted above, we have determined that air safety and the public interest require the adoption of the rule with the changes previously described. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

Cost Impact

There are approximately 400 airplanes of the affected design in the worldwide fleet. We estimate that 133 airplanes of U.S. registry will be affected by this AD, that it will take approximately 6 work hours per airplane to accomplish the required actions, and that the average labor rate is $65 per work hour. Required parts will cost approximately $19 per airplane. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $54,397, or $409 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions. The manufacturer may cover the cost of replacement parts associated with this AD, subject to warranty conditions. Manufacturer warranty remedies may also be available for labor costs associated with this AD. As a result, the costs attributable to the AD may be less than stated above.

Regulatory Impact

The regulations adopted herein 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. Therefore, it is determined that this final rule does not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this action (1) is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.

Adoption of the Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

2. Section 39.13 is amended by adding the following new airworthiness directive:

2004-18-09 Boeing: Amendment 39-13787. Docket 2002-NM-305-AD.

Applicability: Model 777-200 and 777-300 series airplanes, line numbers 001 through 400 inclusive, certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent a possible source of ignition in a flammable leakage zone, which could result in an undetected and uncontrollable fire in the wheel well or wing trailing edge, and a possible fuel tank explosion, accomplish the following:

Replace and Seal

(a) Within 18 months after the effective date of this AD, for all four boost pumps of the main fuel tanks, replace the socket contacts in positions 2, 4, 6, and 7 with new, high-quality gold-plated contacts; and seal the backshell of the connector with potting compound; in accordance with the Accomplishment Instructions of Boeing Service Bulletin 777-28-0028, Revision 1, dated July 15, 2004.

Note 1:

Revision 1 of Boeing Service Bulletin 777-28-0028 incorrectly refers to June 06, 2002, as the date of issuance of the original issue of the service bulletin; the correct date is October 24, 2002.

(b) Replacements done before the effective date of this AD in accordance with Boeing Special Attention Service Bulletin 777-28-0028, dated October 24, 2002, as revised by Boeing Service Bulletin Information Notice 777-28-0028 IN 01, dated February 13, 2003; are acceptable for compliance with the requirements of paragraph (a) of this AD.

Alternative Methods of Compliance

(c) In accordance with 14 CFR 39.19, the Manager, Seattle Aircraft Certification Office, FAA, is authorized to approve alternative methods of compliance (AMOCs) for this AD.

Incorporation by Reference

(d) The actions shall be done in accordance with Boeing Service Bulletin 777-28-0028, Revision 1, dated July 15, 2004. 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 Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or 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: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

Effective Date

(e) This amendment becomes effective on October 19, 2004.