E6-3565. Airworthiness Directives; McDonnell Douglas Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), DC-9-87 (MD-87), and MD-88 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 McDonnell Douglas airplane models, that would have required a one-time inspection for chafing or signs of arcing of the wire bundle for the auxiliary hydraulic pump, and other specified and corrective actions, as applicable. This new action revises the proposed rule by proposing that certain airplanes be required to install additional protective sleeving on the upper portion of the auxiliary hydraulic pump wire assembly. The proposed AD results from reports of shorted wires and evidence of arcing on the power cables of the auxiliary hydraulic pump, as well as fuel system reviews conducted by the manufacturer. We are proposing this AD to prevent shorted wires or arcing at the auxiliary hydraulic pump, which could result in loss of auxiliary hydraulic power, or a fire in the wheel well of the airplane. The proposed actions are also intended to reduce the potential of an ignition source adjacent to the fuel tanks, which, in combination with flammable fuel vapors, could result in a fuel tank explosion and consequent loss of the airplane.

DATES:

Comments must be received by April 10, 2006.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-387-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. 2001-NM-387-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 or 2000 or ASCII text.

The service information referenced in the proposed rule may be obtained from Boeing Commercial Airplanes, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data and Service Management, Dept. C1-L5A (D800-0024). This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California.

FOR FURTHER INFORMATION CONTACT:

Elvin Wheeler, Aerospace Engineer, Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; 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 2001-NM-387-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. 2001-NM-387-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 McDonnell Douglas Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), DC-9-87 (MD-87), and MD-88 airplanes, was published as a supplemental notice of proposed rulemaking (NPRM) in the Federal Register on May 2, 2005 (70 FR 22613) (referred to after this as “the first supplemental NPRM”). The first supplemental NPRM would have required a one-time inspection for chafing or signs of arcing of the wire bundle for the auxiliary hydraulic pump, and other specified and corrective actions, as applicable. The first supplemental NPRM was prompted by reports of shorted wires and evidence of arcing on the power cables of the auxiliary hydraulic pump. That condition, if not corrected, could result in loss of auxiliary hydraulic power, or a fire in the wheel well of the airplane.

Explanation of New Relevant Service Information

Since the issuance of the first supplemental NPRM, Boeing has issued and we have reviewed Boeing Alert Service Bulletin MD80-29A070, Revision 1, dated July 28, 2005. (The first supplemental NPRM refers to Boeing Alert Service Bulletin MD80-29A070, dated August 3, 2004, as the appropriate source of service information for the proposed actions.) Among other things, Revision 1 adds an additional configuration, Configuration 4, which applies to airplanes in Configuration 3 (which are airplanes delivered with 90-degree backshell connector installed) on which the original issue of Boeing Alert Service Bulletin MD80-29A070 was accomplished. The new action for the airplanes in Configuration 4 is installing additional protective sleeving on the upper portion of the auxiliary hydraulic pump wire assembly. We have updated the service bulletin references throughout this second supplemental NPRM to specify Revision 1 of the service bulletin as the acceptable source of service information. We have also revised this second supplemental NPRM to give credit for actions accomplished before the effective date of the AD in accordance with the original issue of the service bulletin, and to require the additional actions specified in Revision 1 for affected airplanes.

Also, Section 2.A., Material Information, of Boeing Alert Service Bulletin MD80-29A070, Revision 1, specifies an increased cost for parts. (The first supplemental NPRM estimates that required parts would cost up to $339.) Thus, we have revised the Cost Impact section of this second supplemental NPRM to specify that required parts could cost up to $524.

Comments

Due consideration has been given to the comments received in response to the first supplemental NPRM.

Request To Address Special Federal Aviation Regulation (SFAR) 88 Findings

One commenter, Boeing, requests that we revise the statement of the unsafe condition in the Summary of the first supplemental NPRM. Boeing points out that the supplemental NPRM does not address the fact that Boeing Alert Service Bulletin MD80-29A070 resulted from the safety assessments conducted under SFAR 88. Boeing observes that the statement of the unsafe condition in the NPRM and first supplemental NPRM mentions only preventing shorted wires or arcing at the auxiliary hydraulic pump, which could result in loss of auxiliary hydraulic power, or a fire in the wheel well of the airplane. Boeing states that the determination that extra protection was needed for the wire bundle for the auxiliary hydraulic pump where the wire bundle was in close proximity to the center fuel tank was based on the findings of the safety assessments conducted under SFAR 88.

We partially agree with the request. We acknowledge that Boeing Alert Service Bulletin MD80-29A070 is the result of safety assessments conducted by Boeing under SFAR 88. Indeed, this is stated in paragraph 1.C., Reason, of that service bulletin. However, Boeing Alert Service Bulletin MD80-29A068, Revision 02 (which Boeing Alert Service Bulletin MD80-29A070 supersedes but does not cancel, as explained in the first supplemental NPRM) also addresses in-service incidents of arcing of the auxiliary hydraulic pump power cables and electrically shorted wires in the right wheel well. We find that it is appropriate to insert a statement in the Summary of this second supplemental NPRM that indicates that this second supplemental NPRM results from “reports of shorted wires and evidence of arcing on the power cables of the auxiliary hydraulic pump, as well as fuel system reviews conducted by the manufacturer.” We have also expanded the statement of the unsafe condition in the Summary and the body of this second supplemental NPRM to state that the proposed actions are also intended to “reduce the potential of an ignition source adjacent to the fuel tanks, which, in combination with flammable fuel vapors, could result in a fuel tank explosion and consequent loss of the airplane.”

Request To Clarify Meaning of “Corrective and Other Specified Actions”

American Airlines (referred to hereafter in this AD as “AAL”), in a comment submitted through the Air Transport Association of America (ATA), requests that we revise paragraph (a) of the first supplemental NPRM to specifically state the requirements to inspect, repair or replace wires, and modify. AAL declares “vague” the statement, “* * * do all applicable corrective and other specified actions * * *.” AAL assumes that “applicable corrective (actions)” refers to repairing or replacing chafed or damaged wiring, and that “other specified actions” refers to installing protective sleeving on the wire bundle, changing the routing of the wiring, and replacing the straight connector backshell with a 90-degree backshell.”

We do not agree that any clarification is needed. The terms “correction actions” and “other specified actions,” as well as “related investigative actions,” are used in many of the ADs we write as a means of clarifying and simplifying the AD requirements. When we use these terms in an AD, the details of these actions are always explained in full in the preamble of the NPRM (or supplemental NPRM), as they were in the first supplemental NPRM, under the heading “Explanation of New Relevant Service Information.” We have not changed this second supplemental NPRM in this regard. However, for the convenience of affected operators, we will reiterate the explanation of “corrective and other specified actions” that appears in the preamble of the first supplemental NPRM:

“The service bulletin also describes procedures for the following corrective and other specified actions:

• Repairing chafed or damaged wiring, or replacing it with new wiring, as applicable.
• Installing protective sleeving on the wire bundle.
• Changing the routing of the wire bundle for the auxiliary hydraulic pump and adding additional clamps.
• Adding snap tubing on a portion of the wire bundle.
• Replacing the existing connector backshell with a 90-degree backshell, if necessary.”

Clarification of Alternative Method of Compliance (AMOC) Paragraph

We have revised this action to clarify the appropriate procedure for notifying the principal inspector before using any approved AMOC on any airplane to which the AMOC applies.

Conclusion

Since these changes expand the scope of the originally proposed rule, the FAA has determined that it is necessary to reopen the comment period to provide additional opportunity for public comment.

Cost Impact

There are approximately 1,063 airplanes of the affected design in the worldwide fleet. We estimate that 732 airplanes of U.S. registry would be affected by this proposed AD, that it would take up to 12 work hours per airplane to accomplish the proposed actions, and that the average labor rate is $65 per work hour. Required parts would cost up to $524 per airplane. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be up to $954,528, or up to $1,304 per airplane.

For airplanes in Configuration 4, as defined in Boeing Alert Service Bulletin MD80-29A070, Revision 1, it would take approximately 2 work hours to accomplish the proposed additional action, at an average labor rate of $65 per work hour. Required parts would cost approximately $40 per airplane. Based on these figures, the cost impact of this action on an affected airplane is estimated to be $170 per airplane. (We do not know how many airplanes will be in Configuration 4.)

The cost impact figures discussed above are 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. 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.

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 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:

McDonnell Douglas: Docket 2001-NM-387-AD.

Applicability

Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), DC-9-87 (MD-87), and MD-88 airplanes; certificated in any category; as identified in Boeing Alert Service Bulletin MD80-29A070, Revision 1, dated July 28, 2005.

Compliance

Required as indicated, unless accomplished previously. To prevent shorted wires or arcing at the auxiliary hydraulic pump, which could result in loss of auxiliary hydraulic power, or a fire in the wheel well of the airplane; and to reduce the potential of an ignition source adjacent to the fuel tanks, which, in combination with flammable fuel vapors, could result in a fuel tank explosion and consequent loss of the airplane; accomplish the following:

One-Time Inspection

(a) For airplanes in Configurations 1 through 3, as defined in Boeing Alert Service Bulletin MD80-29A070, Revision 1, dated July 28, 2005: Within 18 months after the effective date of this AD, do a one-time general visual inspection for chafing or signs of arcing of the wire bundle for the auxiliary hydraulic pump, and do all applicable corrective and other specified actions, in accordance with the Accomplishment Instructions of the service bulletin. Accomplish all applicable corrective actions before further flight after the inspection.

Note 1:

For the purposes of this AD, a general visual inspection is: “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to ensure visual access to all surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.”

Installation of Additional Wiring Protection

(b) For airplanes in Configuration 4, as defined in Boeing Alert Service Bulletin MD80-29A070, Revision 1, dated July 28, 2005: Within 18 months after the effective date of this AD, install additional protective sleeving on the upper portion of the auxiliary hydraulic pump wire assembly in accordance with the procedures under Configuration 4 in the Accomplishment Instructions of the service bulletin.

Actions Accomplished Previously

(c) Actions accomplished before the effective date of this AD in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD80-29A070, dated August 3, 2004, are acceptable for compliance with paragraph (a) of this AD, except that the additional requirements of paragraph (b) of this AD must be done on airplanes in Configuration 4, as defined in Boeing Alert Service Bulletin MD80-29A070, Revision 1, dated July 28, 2005.

Alternative Methods of Compliance

(d)(1) In accordance with 14 CFR 39.19, the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, is authorized to approve alternative methods of compliance for this AD.

(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.

Issued in Renton, Washington, on March 7, 2006.

Kalene C. Yanamura,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.