Airworthiness Directives; The Boeing Company Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. This proposed AD was prompted by reports of chaffing, arcing, and burning damage to the control cabin overhead wiring and ducting with smoke and fire caused by metal clamps installed on certain hoses. This proposed AD would require inspecting for the presence of metal clamps, replacing metal clamps installed on the hoses to the air conditioning temperature sensor, gasper air outlet, and diffuser on the left side of the control cabin with plastic tie straps, and inspecting for and repairing damaged wire bundles. We are proposing this AD to prevent damage to wire bundles, which could cause electrical arcing that could result in a fire or smoke in the control cabin of the airplane.

DATES:

We must receive comments on this proposed AD by November 12, 2013.

ADDRESSES:

You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: 202-493-2251.
• 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.
• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-544-5000, extension 1; fax 206-766-5680; Internet https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov;; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (phone: 800-647-5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Marie Hogestad, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: (425) 917-6418; fax: (425) 917-6590; email: marie.hogestad@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2013-0831; Directorate Identifier 2013-NM-125-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those comments.

We will post all comments we receive, without change, to http://www.regulations.gov,, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

We have received numerous reports of incorrectly installed metal clamps on the hoses to the air conditioning temperature sensor, gasper air outlet, and diffuser on the left side of the control cabin at station (STA) 259.5, many of which have led to wire bundle chaffing and in several cases led to arcing and burning damage to the control cabin overhead wiring and ducting with smoke and fire. Incorrectly installed metal clamps, if not corrected, could cause wire bundle damage and electrical arcing that could result in a fire or smoke in the control cabin of the airplane.

Relevant Service Information

We reviewed Boeing Service Bulletin 737-21-1186, dated April 17, 2012. For information on the procedures, see this service information at http://www.regulations.gov by searching for Docket No. FAA-2013-0831.

FAA's Determination

We are proposing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.

Proposed AD Requirements

This proposed AD would require accomplishing the actions specified in the service information identified previously, except as discussed under “Differences Between the Proposed AD and the Service Information.”

Differences Between the Proposed AD and the Service Information

While Boeing Service Bulletin 737-21-1186, dated April 17, 2012 does not specify a compliance time, this proposed AD would require doing the inspection and replacement within 60 months after the effective date of this AD.

While Boeing Service Bulletin 737-21-1186, dated April 17, 2012, requires doing a general visual inspection for correct part number and correct installation of metal clamps, this proposed AD would require doing a general visual inspection to determine if any metal clamp is installed on the hoses to the air conditioning temperature sensor, gasper air outlet, and diffuser on the left side of the control cabin at STA 259.5.

While Boeing Service Bulletin 737-21-1186, dated April 17, 2012, allows the continued use of metal clamps, this proposed AD would require operators to replace each metal clamp with a plastic tie strap.

While Boeing Service Bulletin 737-21-1186, dated April 17, 2012, specifies to contact Boeing for instructions for certain airplanes, this proposed AD would require that those actions be done in one of the following ways:

• In accordance with a method that we approve; or
• Using data that meets the certification basis of the airplane, and that has been approved by the Boeing Commercial Airplanes Organization Designation Authorization (ODA) whom we have authorized to make those findings.

Costs of Compliance

We estimate that this proposed AD affects 426 airplanes of U.S. registry.

We estimate the following costs to comply with this proposed AD:

We have received no definitive data that would enable us to provide cost estimates for the on-condition actions specified in this proposed AD. We have no way of determining the number of products that may need these 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 Findings

We 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 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),

(3) Will not affect intrastate aviation in Alaska, and

(4) 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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• 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.

2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):

The Boeing Company: Docket No. FAA-2013-0831; Directorate Identifier 2013-NM-125-AD.

(a) Comments Due Date

We must receive comments by November 12, 2013.

(b) Affected ADs

None.

(c) Applicability

This AD applies to The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes, certificated in any category, as identified in Boeing Service Bulletin 737-21-1186, dated April 17, 2012.

(d) Subject

Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 21, Air conditioning.

(e) Unsafe Condition

This AD was prompted by reports of chaffing, arcing, and burning damage to the control cabin overhead wiring and ducting with smoke and fire caused by metal clamps installed on certain hoses. We are issuing this AD to prevent damage to wire bundles, which could cause electrical arcing that could result in a fire or smoke in the control cabin of the airplane.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done.

(g) Inspection, Replacement, and Repair

For airplanes identified in Groups 1 and 2 in Boeing Service Bulletin 737-21-1186, dated April 17, 2012: Within 60 months after the effective date of this AD, do the actions in (g)(1) and (g)(2) of this AD.

(1) Do a general visual inspection to determine if any metal clamp is installed on the hoses to the air conditioning temperature sensor, gasper air outlet, and diffuser on the left side of the control cabin at (station) STA 259.5, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-21-1186, dated April 17, 2012. If any metal clamp is found installed, before further flight, replace each metal clamp with a plastic tie strap, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-21-1186, dated April 17, 2012.

(2) Do a general visual inspection for damage to the adjacent wire bundles and repair any damaged wire bundles in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-21-1186, dated April 17, 2012. Do all applicable repairs before further flight.

(h) Inspection, Replacement, and Repair

For airplanes identified in Group 3 in Boeing Service Bulletin 737-21-1186, dated April 17, 2012: Within 60 months after the effective date of this AD, replace any metal clamp installed on the hoses to the air conditioning temperature sensor, gasper air outlet, and diffuser on the left side of the control cabin at STA 259.5, and inspect adjacent wire bundles and repair any damage, before further flight, using a method approved in accordance with the procedures specified in paragraph (j) of this AD.

(i) Parts Installation Prohibition

For all airplanes: As of the effective date of this AD, no person may install a metal clamp on the hoses to the air conditioning temperature sensor, gasper air outlet, and the diffuser on the left side of the control cabin at STA 259.5.

(j) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in the Related Information section of this AD. Information may be emailed to: 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.

(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.

(3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD if it is approved by the Boeing Commercial Airplanes Organization Designation Authorization (ODA) that has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD.

(k) Related Information

(1) For more information about this AD, contact Marie Hogestad, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: (425) 917-6418; fax: (425) 917-6590; email: marie.hogestad@faa.gov.

(2) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P. O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-544-5000, extension 1; fax 206-766-5680; Internet https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.