E6-12948. Airworthiness Directives; Lockheed Model L-1011 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 Lockheed Model L-1011 series airplanes. This proposed AD would require a one-time detailed inspection of the C112 harness clamp assembly for proper installation, a one-time detailed inspection of the C112 and C162 harness assemblies for damage, and corrective actions if necessary. This proposed AD results from a report of electrical arcing of the essential bus feeder cables behind hinged circuit breaker panel CB3 P-K. We are proposing this AD to prevent arcing of essential bus feeder cables due to improper installation of the harness C112 clamp assembly, which could result in loss of electrical systems and smoke and/or fire behind the CB3 P-K hinged circuit breaker panel in the flight compartment.

DATES:

We must receive comments on this proposed AD by September 25, 2006.

ADDRESSES:

Use one of the following addresses to submit comments on this proposed AD.

• DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
• Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
• Mail: Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., Nassif Building, room PL-401, Washington, DC 20590.
• Fax: [phone].
• Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Contact Lockheed Martin Aircraft & Logistics Center, 120 Orion Street, Greenville, South Carolina 29605, for the service information identified in this proposed AD.

FOR FURTHER INFORMATION CONTACT:

Robert Chupka, Aerospace Engineer, Systems and Equipment Branch, ACE-119A, FAA, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, Suite 450, Atlanta, Georgia 30349; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any relevant written data, views, or arguments regarding this proposed AD. Send your comments to an address listed in the ADDRESSES section. Include the docket number “FAA-2006-25554; Directorate Identifier 2006-NM-123-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this proposed AD. Using the search function of that Web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you may visit http://dms.dot.gov.

Examining the Docket

You may examine the AD docket on the Internet at http://dms.dot.gov,, or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone [phone]) is located on the plaza level of the Nassif Building at the DOT street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after the Docket Management System receives them.

Discussion

We have received a report of electrical arcing of the essential bus feeder cables behind hinged circuit breaker panel CB3 P-K that occurred during maintenance, causing extensive damage to the surrounding area, on a Lockheed Model L-1011 series airplane. Investigation of the arcing revealed that the cushion clamp securing wire harness assembly C112 was installed incorrectly, with the clamp loop on the forward side instead of the aft side of the clamp screw. The improper installation of the cushion clamp allowed the clamp to chafe against the C162 wire harness. We have also received a report indicating that two additional airplanes have been found with improperly installed cushion clamps at this location. This condition, if not corrected, could result in loss of electrical systems and smoke and/or fire behind the CB3 P-K hinged circuit breaker panel in the flight compartment.

Relevant Service Information

We have reviewed Lockheed L-1011 Service Bulletin 093-24-142, dated November 16, 2005. The service bulletin describes procedures for a one-time detailed inspection of the circuit breaker panel clamp assembly for harness C112 just outboard of terminal block 2400 TB17 in the hinged circuit breaker panel CB3 P-K to verify the position of the clamp assembly. It also describes procedures for a one-time detailed inspection of the C112 and C162 harness assemblies for damage (e.g., evidence of chafing, arcing, or deterioration), and corrective actions if necessary. The corrective actions include repositioning the clamp assembly to the correct position and correcting damage found in the C112 and C162 harness assemblies. Accomplishing the actions specified in the service information 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 information described previously, except as discussed under “Difference Between the Proposed AD and the Service Bulletin.”

Difference Between the Proposed AD and the Service Bulletin

Although the service bulletin recommends accomplishing the inspection of the circuit breaker panel clamp assembly for harness C112 “at the next scheduled maintenance visit,” we have determined that this imprecise compliance time would not address the identified unsafe condition in a timely manner. In developing an appropriate compliance time for this proposed AD, we considered not only the manufacturer's recommendation, but also 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 inspection. In light of all of these factors, we find a compliance time of 90 days for completing the required actions 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 Lockheed.

Costs of Compliance

There are about 126 airplanes of the affected design in the worldwide fleet. The following table provides the estimated costs for U.S. operators to comply with this proposed AD.

Estimated Costs

Action	Work hours	Average labor rate per hour	Parts	Cost per airplane	Number of U.S.-registered airplanes	Fleet cost
Inspection of clamp assembly	2	$80	$0	$160	53	$8,480

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):

Lockheed: Docket No. FAA-2006-25554; Directorate Identifier 2006-NM-123-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by September 25, 2006.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Lockheed Model L-1011-385-1, L-1011-385-1-14, L-1011-385-1-15, and L-1011-385-3 series airplanes, certificated in any category; having serial numbers (S/N) 193A through 193Y inclusive and 293A through 293F inclusive: -1002 through -1250 inclusive.

Unsafe Condition

(d) This AD results from a report of electrical arcing of the essential bus feeder cables behind hinged circuit breaker panel CB3 P-K. We are issuing this AD to prevent arcing of essential bus feeder cables due to improper installation of the harness C112 clamp assembly, which could result in loss of electrical systems and smoke and/or fire behind the CB3 P-K hinged circuit breaker panel in the flight compartment.

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.

Detailed Inspection of the C112 Harness Clamp Assembly

(f) Within 90 days after the effective date of this AD: Do the actions in paragraphs (f)(1) and (f)(2) of this AD by accomplishing all the actions specified in the Accomplishment Instructions of Lockheed L-1011 Service Bulletin 093-24-142, dated November 16, 2005. Do all applicable corrective actions before further flight.

(1) Perform a one-time detailed inspection of the C112 harness clamp assembly to find incorrectly installed harness clamps, and do all applicable corrective actions.

(2) Perform a one-time detailed inspection of the C112 and C162 harness assemblies to find evidence of chafing, arcing, or deterioration, and do all applicable corrective actions.

Note 1:

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

Alternative Methods of Compliance (AMOCs)

(g)(1) The Manager, Atlanta Aircraft Certification Office, FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

(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 August 2, 2006.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.