00-11952. Airworthiness Directives; Boeing Model 767 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 767 series airplanes. This proposal would require installation of sleeving on the 90-minute auxiliary power unit (APU) standby power feeder cable at body station 1351. This proposal is prompted by a report of damage to the 90-minute APU standby power feeder cable caused by shifting of unrestrained cargo containers during flight. The actions specified by the proposed AD are intended to prevent damage to the 90-minute APU standby power feeder cable, which could result in arcing between the standby power feeder cable and the shroud of the APU fuel line, penetration of the fuel line shroud, and a consequent fire in the main deck floor above the aft cargo compartment.

DATES:

Comments must be received by June 26, 2000.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2000-NM-91-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal holidays.

The service information referenced in the proposed rule may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT:

Holly Thorson, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Transport Airplane Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this notice may be changed in light of the comments received.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2000-NM-91-AD.” The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2000-NM-91-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The FAA has received a report indicating that unrestrained cargo containers shifted during flight and caused damage on a Boeing Model 767 series airplane that is equipped with an auxiliary power unit (APU) extended standby power system. The cargo containers damaged the 90-minute APU standby power feeder cable and the cabin floor support beam at body station (BS) 1351 on the right side of the airplane. Investigation revealed evidence of arcing between the cable and the beam. Though the reported damage occurred on the right side of the airplane, an unrestrained cargo container that shifts during flight could cause similar damage on the left side of the airplane. On the left side of the airplane, the 90-minute APU standby power feeder cable is routed close to the APU fuel line. Should damage to the 90-minute APU standby power feeder cable occur on the left side of the airplane, the damaged power feeder cable could arc against the shroud of the APU fuel line. This condition, if not corrected, could result in penetration of the fuel line shroud and a consequent fire in the main deck floor above the aft cargo compartment.

Explanation of Relevant Service Information

The FAA has reviewed and approved Boeing Alert Service Bulletin 767-24A0126, dated February 24, 2000. That alert service bulletin describes procedures for installation of sleeving on the 90-minute APU standby power feeder cable at BS 1351 on the left side of the airplane. Installation of this sleeving is intended to protect the cable from being damaged in the event that an unrestrained cargo container shifts during flight and impacts the cable. Accomplishment of the action specified in the service bulletin is intended to adequately address the identified unsafe condition.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require accomplishment of the actions specified in the service bulletin described previously.

Cost Impact

There are approximately 151 airplanes of the affected design in the worldwide fleet. The FAA estimates that 14 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 1 work hour per airplane to accomplish the proposed action, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $840, or $60 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

Regulatory Impact

The regulations proposed herein 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. Therefore, it is determined that this proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this 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) if promulgated, 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 copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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.

§ 39.13

[Amended]

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

Boeing: Docket 2000-NM-91-AD.

Applicability: Model 767 series airplanes; as listed in Boeing Alert Service Bulletin 767-24A0126, dated February 24, 2000; certificated in any category.

Note 1:

This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (b) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To prevent damage to the 90-minute auxiliary power unit (APU) standby power feeder cable, which could result in arcing between the standby power feeder cable and the shroud of the APU fuel line, penetration of the fuel line shroud, and a consequent fire in the main deck floor above the aft cargo compartment, accomplish the following:

Installation of Sleeving

(a) Within 6 months after the effective date of this AD, install sleeving on the 90-minute APU standby power feeder cable at body station 1351 on the left side of the airplane, in accordance with Boeing Alert Service Bulletin 767-24A0126, dated February 24, 2000.

Alternative Methods of Compliance

(b) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO.

Note 2:

Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.

Special Flight Permits

(c) Special flight permits may be issued in accordance with §§ 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

Issued in Renton, Washington, on May 8, 2000.

Vi L. Lipski,

Acting Manager,, Transport Airplane Directorate, Aircraft Certification Service.