E7-17280. Airworthiness Directives; Boeing Model 757-200, -200CB, 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 757-200, -200CB, and -300 series airplanes. This proposed AD would require doing a detailed inspection for damage of the wire bundle of the right recirculation fan, and repair if necessary. This proposed AD would also require re-routing the wire bundle of the right recirculation fan. This proposed AD results from a report indicating that, during landing of a Model 757 airplane, an overheat warning and smoke occurred in the main cabin, and the right recirculation fan stopped operating. We are proposing this AD to prevent damage of the wiring bundle of the right recirculation fan. Such damage could result in a short circuit and possible fire in the mix bay or smoke in the main cabin.

DATES:

We must receive comments on this proposed AD by October 15, 2007.

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: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Fax: [phone].
• Hand Delivery: Room W12-140 on the ground floor of the West Building, 1200 New Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207, for the service information identified in this proposed AD.

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 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-2007-29067; Directorate Identifier 2007-NM-148-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 airworthiness directive (AD) docket on the Internet at http://dms.dot.gov or in person at the Docket Operations office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Operations office (telephone [phone]) is located on the ground floor of the West 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 indicating that, during landing of a Model 757 airplane, an overheat warning and smoke occurred in the main cabin, and the right recirculation fan stopped operating. Investigation revealed fire damage to the right recirculation fan, the fan wiring bundle and electrical connector, and the insulation blankets in the mix bay. A fire, which extinguished without aid, had ignited in the top layer of the insulation blanket. The fire might have resulted from lint or dust touching a short circuit in the fan wiring bundle caused by chafing of the wire bundle against adjacent structure. This condition, if not corrected, could result in fire in the mix bay or smoke in the main cabin.

Relevant Service Information

We have reviewed Boeing Service Bulletin 757-21-0109, dated December 15, 2006. The service bulletin describes procedures for doing a detailed inspection for damage of the wire bundle of the right recirculating fan and repair if necessary. The service bulletin also describes procedures, including re-orienting the electrical connector, for re-routing the wire bundle of the right recirculating fan. 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.

Costs of Compliance

There are about 920 airplanes of the affected design in the worldwide fleet. This proposed AD would affect about 560 airplanes of U.S. registry. The proposed actions would take about 2 work hours per airplane, at an average labor rate of $80 per work hour. Required parts would cost about $81 per airplane. Based on these figures, the estimated cost of the proposed AD for U.S. operators is $134,960, or $241 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-2007-29067; Directorate Identifier 2007-NM-148-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by October 15, 2007.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Boeing Model 757-200, -200CB, and -300 series airplanes; certificated in any category; as identified in Boeing Service Bulletin 757-21-0109, dated December 15, 2006.

Unsafe Condition

(d) This AD results from a report indicating that, during landing of a Model 757 airplane, an overheat warning and smoke occurred in the main cabin, and the right recirculation fan stopped operating. We are issuing this AD to prevent damage of the wiring bundle of the right recirculation fan. Such damage could result in a short circuit and possible fire in the mix bay or smoke in the main cabin.

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.

Inspection and Corrective Actions

(f) Within 24 months after the effective date of this AD, do all actions required by paragraphs (f)(1) and (f)(2) of this AD, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 757-21-0109, dated December 15, 2006.

(1) Do a detailed inspection for damage of the wire bundle of the right recirculation fan, and repair any damage before further flight.

(2) Re-route the wire bundle and re-orient the electrical connector of the right recirculation fan.

Alternative Methods of Compliance (AMOCs)

(g)(1) The Manager, Seattle 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) 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 August 17, 2007.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.