Airworthiness Directives; The Boeing Company Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to supersede an existing airworthiness directive (AD) that applies to all The Boeing Company Model 727 airplanes. The existing AD currently requires repetitive inspections of the in-tank fuel boost pump wiring to detect chafing of the wire insulation, evidence of electrical arcing, or arc-through of the conduit wall, and applicable corrective action; and installation of sleeving over the in-tank fuel boost pump wires. The existing AD also requires repetitive inspections for damage of a certain electrical wire and sleeve, and arcing damage of the conduit and signs of fuel leakage into the conduit; applicable investigative and corrective actions; and repetitive engine fuel suction feed operational tests. Since we issued that AD, we received a report of damage found to the sleeve, jacket, and insulation on an electrical wire during a repetitive inspection. This proposed AD would require replacement of the wire bundles for the wing and center fuel boost pumps with new, improved wire bundles, installation of convoluted liners, and related investigative and corrective actions if necessary. This proposed AD would also require replacement of the fuel quantity indicating system (FQIS) wires with new, improved wires; a low-frequency eddy current inspection for cracking; and repair if necessary. This proposed AD would also require revising the maintenance program to incorporate changes to the airworthiness limitations section. We are proposing this AD to detect and correct chafing of the fuel boost pump electrical wiring and leakage of fuel into the conduit, and to prevent electrical arcing between the wiring and the surrounding conduit, which could result in arc-through of the conduit, and consequent fire or explosion of the fuel tank.

DATES:

We must receive comments on this proposed AD by November 26, 2012.

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, WA 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, WA. 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:

Rebel Nichols, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6509; fax: 425-917-6590; email: rebel.nichols@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2012-1069; Directorate Identifier 2012-NM-044-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

On May 1, 2007, we issued AD 2007-11-08, Amendment 39-15065 (72 FR 28594, May 22, 2007), for all The Boeing Company Model 727, 727C, 727-100, 727-100C, 727-200, and 727-200F series airplanes. That AD requires repetitive inspections of the in-tank fuel boost pump wiring to detect chafing of the wire insulation, evidence of electrical arcing, or arc-through of the conduit wall, and applicable corrective action; and installation of sleeving over the in-tank fuel boost pump wires as a method to protect the wiring from chafing. That AD also requires repetitive inspections for damage of the electrical wire and sleeve that run to the fuel boost pump through a conduit in the fuel tank, and arcing damage of the conduit and signs of fuel leakage into the conduit; applicable investigative and corrective actions; repetitive engine fuel suction feed operational tests; an engine fuel suction feed operational test; related investigative and corrective actions, as applicable; and sending inspection results and damaged parts to the manufacturer.

Actions Since Existing AD (72 FR 28594, May 22, 2007) Was Issued

In the preamble to AD 2007-11-08, Amendment 39-15065 (72 FR 28594, May 22, 2007), the FAA indicated that the actions required by that AD were considered “interim action” and that further rulemaking action was being considered. The FAA now has determined that further rulemaking action is indeed necessary, and this proposed AD follows from that determination.

Further, since we issued AD 2007-11-08, Amendment 39-15065 (72 FR 28594, May 22, 2007), we received a report of damage found to the sleeve, jacket, and insulation on an electrical wire during a repetitive inspection approximately 21,000 flight hours after installation of the sleeve. (The inspection interval in AD 2007-11-08 is 30,000 flight hours.) The sleeve and jacket were worn through, exposing the insulation on the electrical wire inside the jacket. The actions developed by the manufacturer eliminate the possibility of wiring damage during reinstallation following the repetitive inspections.

Relevant Service Information

We reviewed Boeing Alert Service Bulletin 727-28A0133, dated October 5, 2011. This service bulletin describes procedures for replacing wire bundles for the wing and center fuel boost pumps, installing convoluted liners, and related investigative and corrective actions. This service bulletin specifies that doing these actions eliminates the need for the inspections specified in Boeing Alert Service Bulletin 727-28A0132, dated February 22, 2007 (which is referenced as the appropriate source of service information for inspections specified in AD 2007-11-08, Amendment 39-15065 (72 FR 28594, May 22, 2007)). Replacing the wire bundles and installing the convoluted liners includes:

• Installing new ground brackets, removing fuel boost pumps from the fuel boost pump housing, and removing wire bundles and sleeves.
• Removing or stowing fuel boost pump wire bundles, installing new convoluted liners and new wire bundles in the fuel boost pump conduits.
• Routing new wire bundles.
• Installing fuel boost pumps and making changes to the wire bundles.
• Installing the ground stud assembly for wire bundles.

Related investigative actions include testing the fuel tank conduits for leaks and testing the fuel boost pumps. Corrective actions include repairing or replacing the fuel tank conduit.

Boeing Alert Service Bulletin 727-28A0133, dated October 5, 2011, specifies prior or concurrent accomplishment of the actions specified in Boeing Service Bulletin 727-28-0131, dated August 18, 2010, for the following actions:

• Replacing the FQIS wires with new wires, which includes: Installing new ground brackets in the left and right wing, a new disconnect bracket in the cargo compartment, and a new tie plate in the cargo compartment; making and installing new doublers in the left and right wing; installing new standoffs in the left and right wing; drilling new holes or ground holes in left and right wing; changing the wire bundles; making changes to wire bundle routes; and making changes to wire bundles and assembling wire bundle overbraids.
• Doing a low-frequency eddy current (LFEC) inspection for cracks in certain locations of the fuselage skin, and repair if necessary, in accordance with Boeing Service Bulletin 727-28-0131, dated August 18, 2010.

Airworthiness Limitation Instruction (ALI) Task 28-AWL-20, “Fuel Boost Pump Wires in Conduit Installation—In Fuel Tank;” and Critical Design Configuration Control Limitation (CDCCL) Task 28-AWL-21, “Fuel Boost Pump Wires in Conduit Installation—In Fuel Tank;” of Section 9 of Boeing 727-100/200 Airworthiness Limitations (AWLs), D6-8766-AWL, Revision August 2010, provide maintenance instructions for the wiring changes and replace the requirements of CDCCL Task 28-AWL-14 of Section 9 of Boeing 727-100/200 Airworthiness Limitations (AWLs), D6-8766-AWL.

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 retain certain requirements of AD 2007-11-08, Amendment 39-15065 (72 FR 28594, May 22, 2007). This proposed AD would also require accomplishing the actions specified in the service information described previously, except as provided under “Differences Between the AD and the Service Information.”

Differences Between the Proposed AD and the Service Information

Although Boeing Alert Service Bulletin 727-28A0133, dated October 5, 2011, specifies that operators may contact the manufacturer for disposition of certain repair conditions, this proposed AD would require operators to repair those conditions using a method approved by the FAA.

Change to Existing AD

This proposed AD would remove the reporting requirements of paragraph (m) of AD 2007-11-08, Amendment 39-15065 (72 FR 28594, May 22, 2007). The inspection report requirement gathered sufficient information for the manufacturer to develop corrective actions.

This proposed AD would retain certain requirements of AD 2007-11-08, Amendment 39-15065 (72 FR 28594, May 22, 2007). Since AD 2007-11-08 was issued, the AD format has been revised, and certain paragraphs have been rearranged. Also, certain notes have been re-designated as paragraphs. As a result, the corresponding paragraph identifiers have changed in this proposed AD, as listed in the following table:

Costs of Compliance

We estimate that this proposed AD affects 569 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 a cost estimate for the on-condition actions specified in this proposed AD.

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),

(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.