03-1828. Airworthiness Directives; Boeing Model 767-200, -300, and -300F Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Supplemental notice of proposed rulemaking; reopening of comment period.

SUMMARY:

This document revises an earlier proposed airworthiness directive (AD), applicable to certain Boeing Model 767-200, -300, and -300F series airplanes, that would have required a one-time inspection for discrepancies of certain wire bundles in the forward cargo compartment, and corrective actions, if necessary. This new action revises the proposed rule by extending the compliance time and expanding the inspection area. The actions specified by this new proposed AD are intended to prevent damage to wire bundles, particularly those of the fuel quantity indication system (FQIS), which are located in the subject area. Damage of FQIS wires could cause arcing between those wires and power wires in the damaged wire bundle, and may lead to transmission of electrical energy into the fuel tank, which would result in a potential source of ignition in the fuel tank. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by February 24, 2003.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2000-NM-409-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to [phone]. Comments may also be sent via the Internet using the following address: [e-mail]. Comments sent via fax or the Internet must contain “Docket No. 2000-NM-409-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 for Windows or ASCII text.

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:

Elias Natsiopoulos, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, 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 action may be changed in light of the comments received.

Submit comments using the following format:

• Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
• For each issue, state what specific change to the proposed AD is being requested.
• Include justification (e.g., reasons or data) for each request.

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 action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2000-NM-409-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-409-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to add an airworthiness directive (AD), applicable to certain Boeing Model 767-200, -300, and -300F series airplanes, was published as a notice of proposed rulemaking (NPRM) in the Federal Register on October 26, 2001 (66 FR 54171). That NPRM proposed to require a one-time inspection for discrepancies of certain wire bundles in the forward cargo compartment, and corrective actions, if necessary. That NPRM was prompted by a report indicating that, prior to engine start-up on a Boeing Model 767 series airplane, several circuit breakers tripped and the flight crew observed unusual messages on the engine indication and crew alerting system display. An investigation revealed that numerous wires in certain wire bundles had melted and burned. The affected wire bundles were located on the ceiling of the forward cargo compartment, and had chafed. Wires for the fuel quantity indication system (FQIS), which penetrate the fuel tank, are routed through one of the wire bundles that was damaged in the reported incident. Damage of FQIS wires could cause arcing between those wires and power wires in the damaged wire bundle, and may lead to transmission of electrical energy into the fuel tank, which would result in a potential source of ignition in the fuel tank.

Actions Since Issuance of Previous Proposal

Due consideration has been given to the comments received in response to the original NPRM. Some of the comments have resulted in changes to the original NPRM.

Support for the Original NPRM

One operator supports the original NPRM.

Request for Revised Service Information

One commenter, an operator, has identified three problems in Boeing Service Bulletin 767-24A0128, dated May 11, 2000, which was identified as the appropriate service information for the actions specified in the original NPRM. First, the Panduit strap does not fit into the cable spacer, as described in that service bulletin. Second, the specified 0.5-inch clearance between the wire bundles and the cargo liner is impossible to achieve. Third, the cargo liner panel is mislabeled in Figure 1, Sheet 2, of the service bulletin.

The FAA agrees. Boeing has revised the service bulletin, which the FAA has reviewed and approved. Boeing Service Bulletin 767-24A0128, Revision 2, dated May 23, 2002, addresses all of the commenter's concerns: The new Panduit straps will fit the cable spacers; the space requirements between the wire bundles and the cargo ceiling liner standoff have been revised to 0.25 inch for sleeving and 0.13 inch for sleeving and spacers; and Figure 1, Sheet 2, has been revised to identify the “floor beam” rather than the “ceiling liner.” The FAA has revised this supplemental NPRM to cite Revision 2 of the service bulletin as the appropriate service information for the proposed actions. Revision 2 of the service bulletin expands the inspection to include areas that were inadvertently omitted from the original service bulletin and Revision 1. Specifically, this supplemental NPRM would require inspection of wire bundles between right buttock line (RBL) 40 and RBL 70. (The original NPRM proposed to require inspection of bundles between RBL 40 and RBL 54.)

Request To Revise Cost Estimate

One commenter, an operator, recommends revising the Cost Impact section. Rather than 2 work hours to accomplish all the actions specified in the original NPRM, the commenter suggests that this figure be revised to 32 work hours per airplane, broken down as follows: 2 work hours to access the area, 2 work hours to inspect the wire bundles, 26 work hours to protect the wire bundles (the commenter reports finding inadequate clearance on the wire bundles on nearly all its airplanes and is adding protection to the bundles on each airplane), and 2 work hours for restoration.

The FAA partially agrees. Although moderating the clearance requirements (as described previously) would considerably reduce the time necessary to accomplish the corrective actions, only the inspection and clearance measurement of the wire bundles would actually be required by this supplemental NPRM. The economic analysis of an AD is limited to the cost of actions actually required by the rule. It does not consider the cost of conditional actions, which would be required to be accomplished—regardless of AD direction—to correct an unsafe condition identified on an airplane and to ensure operation of that airplane in an airworthy condition, as required by the Federal Aviation Regulations.

Request To Extend the Compliance Time

Two commenters, both operators, request that the compliance time be extended from 15 months to 18 months. One operator states that an 18-month compliance time would correspond to available maintenance opportunities for the fleet, based on the work-hour estimates, without compromising safety. The other operator requests that the compliance time reflect ATA “Spec 111” recommended guidelines for such non-emergency-related safety issues, and suggests that an 18-month compliance time would coincide with regularly scheduled “C” check visits.

The FAA agrees. In light of the revised work-hour estimates provided in Revision 2 of the service bulletin, the FAA finds that the proposed 18-month compliance time is more appropriate for the majority of operators to accomplish the corrective action that would be mandated by this supplemental NPRM and still ensure the safety of the fleet. This supplemental NPRM has been revised accordingly.

Request To Clarify Identity of Airplanes Subject to Inspection Requirement

One commenter, an operator, requests that the proposed AD be revised to clarify that only the inspection is required and operators may choose to rework the wire bundles if “deemed necessary.” The commenter requests that the difference between the service bulletin instructions and the AD inspection requirements be clearly defined.

The FAA partially agrees. The rework instructions in Revision 2 of the service bulletin correspond to the proposed requirements in this supplemental NPRM. However, the FAA disagrees with the request to require only the inspection of the wire bundles and to permit operators to determine whether corrective action is needed. The FAA finds that the need to rework the wire bundles is not a discretionary option for operators. If conditions exist that require the rework (as specified in this supplemental NPRM and clarified in Revision 2 of the service bulletin), then operators are required to comply with the rework requirements. The rework conditions proposed in this supplemental NPRM are the same as those recommended in Revision 2 of the service bulletin. No further change to this supplemental NPRM is necessary.

Conclusion

Revision 2 of the service bulletin specifies additional areas to be inspected. Since this change expands the scope of the original NPRM, the FAA has determined that it is necessary to reopen the comment period to provide additional opportunity for public comment.

Difference Between Service Bulletin and Proposed AD

The service bulletin recommends accomplishing the inspection “at the earliest opportunity when manpower and facilities are available.” However, the FAA has determined that such a compliance time will not ensure that operators address the unsafe condition in a timely manner. In developing an appropriate compliance time for this supplemental NPRM, we considered not only the manufacturer's recommendation, but the degree of urgency associated with addressing the subject unsafe condition, and the time necessary to accomplish the actions. In light of all of these factors, the FAA finds that an 18-month compliance time represents an appropriate length of time to allow affected airplanes to continue to be operated without compromising safety.

Clarification of Inspection Type

While the service bulletin specifies that operators “inspect” (for chafing or damage of wire bundles), this supplemental NPRM would require a “detailed inspection.” The FAA has determined that the procedures as described in the service bulletin should be considered a detailed inspection. Note 2 has been revised in this supplemental NPRM to define this type of inspection.

Cost Impact

There are approximately 774 airplanes of the affected design in the worldwide fleet. The FAA estimates that 303 airplanes of U.S. registry would be affected by this supplemental NPRM, that it would take approximately 2 work hours per airplane to accomplish the proposed inspection, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of this supplemental NPRM on U.S. operators is estimated to be $36,360, or $120 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 supplemental NPRM 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.

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-409-AD.

Applicability: Model 767-200, -300, and -300F series airplanes; certificated in any category; as listed in Boeing Alert Service Bulletin 767-24A0128, Revision 2, dated May 23, 2002.

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 of wire bundles in the forward cargo compartment, particularly wires of the fuel quantity indication system (FQIS) installed in that area, which could cause arcing between the FQIS wires and power wires in the damaged wire bundle, lead to transmission of electrical energy into the fuel tank, and result in a potential source of ignition in the fuel tank, accomplish the following:

Inspection and Follow-on Actions

(a) Within 18 months after the effective date of this AD, do a one-time detailed inspection to detect discrepancies of all wire bundles routed along the ceiling of the forward cargo compartment from station 368 through 742 at right buttock lines 40 through 70, according to the Accomplishment Instructions of Boeing Alert Service Bulletin 767-24A0128, Revision 2, dated May 23, 2002. Discrepancies include chafing or damage of wire bundles near stand-offs that attach the cargo ceiling liner to the floor beams.

(1) Before further flight, repair any discrepancy, according to the Accomplishment Instructions of the service bulletin.

(2) Before further flight, examine the clearance between the wire bundles in the forward cargo compartment and the cargo liner standoffs, according to the service bulletin.

(i) If the clearance is greater than 0.25 inch: No further action is required by this AD.

(ii) If the clearance is 0.25 inch or less: Before further flight, install sleeving, cable spacers, and straps, as applicable, according to the Accomplishment Instructions of the service bulletin.

Note 2:

For the purposes of this AD, a detailed inspection is defined as: “An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.”

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. 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 3:

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 January 22, 2003.

Vi L. Lipski,

Manager, Transport Airplane Directorate, Aircraft Certification Service.