E7-24531. Airworthiness Directives; Boeing Model 767-200 and -300 Series Airplanes

AGENCY:

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

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for certain Boeing Model 767-200 and -300 series airplanes. This proposed AD would require replacing the wire segments of the four Fuel Quantity Indicating System (FQIS) wire bundles with new, improved wire segments. This proposed AD results from operator inspections of the FQIS wire bundles that revealed corrosion at the connections between the ground wire and shield of each of the four FQIS wire bundles. We are proposing this AD to prevent this corrosion, which could reduce system protection of the lightning shield and result in loss of the electrical grounding between the lightning shield and the airplane structure. This condition, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of the airplane.

DATES:

We must receive comments on this proposed AD by February 4, 2008.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Hand Delivery: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this AD, contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (telephone [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Philip Sheridan, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2007-0344; Directorate Identifier 2007-NM-149-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those comments.

We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

Operator inspections of four Fuel Quantity Indicating System (FQIS) wire bundles revealed corrosion at the connections between the ground wire and shield of each of the four wire bundles, on certain Boeing Model 767-200 and -300 series airplanes. Corrosion occurred at the ferrules, which were used for connection of the ground wire. The wire bundle shielding is part of the system protection against a lightning strike. The corrosion reduces system protection against a lightning strike. This condition, if not corrected, could result in loss of the electrical grounding between the lightning shield and the airplane structure. Loss of the electrical grounding between the lightning shield and the airplane structure, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of the airplane.

Relevant Service Information

We have reviewed Boeing Alert Service Bulletin 767-28A0064, Revision 2, dated October 27, 2005. The service bulletin describes procedures for replacing the wire segments of the four FQIS wire bundles with new, improved wire segments. The service bulletin also describes procedures for an operational test of the FQIS following the replacement. Accomplishing the actions specified in the service bulletin is intended to adequately address the unsafe condition.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to exist or develop on other airplanes of this same type design. For this reason, we are proposing this AD, which would require accomplishing the actions specified in the service bulletin described previously, except as discussed under “Difference Between the Proposed AD and Service Bulletin.”

Difference Between the Proposed AD and Service Bulletin

The service bulletin recommends accomplishing the replacement of the wire segments of the four FQIS wire bundles within 48 months after the release date of the service bulletin, but we have determined that this compliance time would not address the identified unsafe condition in a timely manner. In developing an appropriate compliance time for this AD, we considered not only the manufacturer's recommendation, but the degree of urgency associated with addressing the subject unsafe condition, the average utilization of the affected fleet, and the time necessary to perform the replacement. In light of all of these factors, we find a compliance time of 36 months after the effective date of the AD for completing the required replacement to be warranted, in that it represents an appropriate interval of time for affected airplanes to continue to operate without compromising safety. This difference has been coordinated with Boeing.

Costs of Compliance

There are about 608 airplanes of the affected design in the worldwide fleet. This proposed AD would affect about 169 airplanes of U.S. registry. The proposed replacement would take about 42 work hours per airplane, at an average labor rate of $80 per work hour. Required parts would cost about $1,756 per airplane. Based on these figures, the estimated cost of the proposed AD for U.S. operators is $864,604, or $5,116 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.

Regulatory Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 the proposed regulation:

1. Is not a “significant regulatory action” under Executive Order 12866;

2. Is not a “significant rule” under the 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 proposed AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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 Federal Aviation Administration (FAA) amends § 39.13 by adding the following new airworthiness directive (AD):

Boeing: Docket No. FAA-2007-0344; Directorate Identifier 2007-NM-149-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by February 4, 2008.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Boeing Model 767-200 and -300 series airplanes, certificated in any category; as identified in Boeing Alert Service Bulletin 767-28A0064, Revision 2, dated October 27, 2005.

Unsafe Condition

(d) This AD results from operator inspections of the Fuel Quantity Indicating System (FQIS) wire bundles that revealed corrosion at the connections between the ground wire and shield of each of the four FQIS wire bundles. We are issuing this AD to prevent this corrosion, which could reduce system protection of the lightning shield and result in loss of the electrical grounding between the lightning shield and the airplane structure. This condition, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of 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.

Replacement

(f) Within 36 months after the effective date of this AD: Replace the wire segments of the four FQIS wire bundles with new, improved wire segments, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 767-28A0064, Revision 2, dated October 27, 2005.

Credit for Actions Done Using Previous Service Information

(g) Actions accomplished before the effective date of this AD in accordance with Boeing Alert Service Bulletin 767-28A0064, Revision 1, dated February 21, 2002, are considered acceptable for compliance with the corresponding actions specified in this AD.

Alternative Methods of Compliance (AMOCs)

(h)(1) The Manager, Seattle Aircraft Certification Office (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) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. 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.

Issued in Renton, Washington, on December 10, 2007.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.