2010-31375. Airworthiness Directives; The Boeing Company Model 747 Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) that applies to all Model 747 airplanes. The existing AD currently requires repetitive inspections to detect damage of the sleeving and wire bundles of the boost pumps of the numbers 1 and 4 main fuel tanks, and of the auxiliary tank jettison pumps (if installed); replacement of any damaged sleeving with new sleeving; and repair or replacement of any damaged wires with new wires. For airplanes on which any burned wires are found, the existing AD also requires an inspection to detect damage of the conduit, and replacement of any damaged conduit with a serviceable conduit. This proposed AD would reduce the initial compliance time and repetitive inspection interval in the existing AD. This proposed AD results from fleet information indicating that the repetitive inspection interval in the existing AD is too long because excessive chafing of the sleeving continues to occur much earlier than expected between scheduled inspections. We are proposing this AD to detect and correct abrasion of the Teflon sleeving and wires in the bundles of the fuel boost pumps for the numbers 1 and 4 main fuel tanks and of the auxiliary tank jettison pumps (if installed), which could result in electrical arcing between the wires and aluminum conduit and consequent fire or explosion of the fuel tank.

DATES:

We must receive comments on this proposed AD by January 28, 2011.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• 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: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, 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 [phone], extension 1; fax [phone]; e-mail [e-mail]; 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 (telephone [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Jon Regimbal, Aerospace Engineer, Propulsion Branch, ANM-140S, 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 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-2010-1158; Directorate Identifier 2010-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

On December 9, 1997, we issued AD 97-26-07, Amendment 39-10250 (62 FR 65352, December 12, 1997), for all Model 747 airplanes. That AD currently requires repetitive inspections to detect damage of the sleeving and wire bundles of the boost pumps of the numbers 1 and 4 main fuel tanks, and of the auxiliary tank jettison pumps (if installed); replacement of any damaged sleeving with new sleeving; and repair or replacement of any damaged wires with new wires. For airplanes on which any burned wires are found, that AD also requires an inspection to detect damage of the conduit, and replacement of any damaged conduit with a serviceable conduit. That AD resulted from reports of chafing of the sleeving. We issued that AD to detect and correct abrasion of the Teflon sleeving and wires in the bundles of the fuel boost pumps for the numbers 1 and 4 main fuel tanks and of the auxiliary tank jettison pumps (if installed), which could result in electrical arcing between the wires and the aluminum conduit and consequent fire or explosion of the fuel tank.

Actions Since Existing AD Was Issued

Since we issued AD 97-26-07, we received fleet information from the manufacturer indicating that excessive chafing of the sleeving continues to occur much earlier than expected between scheduled inspections. Due to that fact, the manufacturer has revised the service information to reduce the repetitive inspection intervals.

Relevant Service Information

We have reviewed Boeing Alert Service Bulletin 747-28A2204, Revision 3, dated March 11, 2010. The service information reduces the initial compliance time and repetitive inspection interval for detecting damage of the sleeving and wire bundles of the boost pumps of the numbers 1 and 4 main fuel tanks, and of the auxiliary tank jettison pumps (if installed) specified in Boeing Service Bulletin 747-28A2204, Revision 1, dated October 30, 1997. Revision 1 of this service bulletin was referred to in AD 97-26-07 as the appropriate source of service information for accomplishing the specified actions. The actions described in Revision 3 of this service bulletin are essentially the same as those described in Revision 1 of this service bulletin.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to develop on other airplanes of the same type design. For this reason, we are proposing this AD, which would supersede AD 97-26-07 and would retain the requirements of the existing AD at reduced compliance times.

Change to Existing AD

This proposed AD would retain all requirements of AD 97-26-07. Since AD 97-26-07 was issued, the AD format has been revised, and certain paragraphs have been rearranged. As a result, the corresponding paragraph identifiers have changed in this proposed AD, as listed in the following table:

Revised Paragraph Identifiers

Requirement in AD 97-26-07	Corresponding requirement in this proposed AD
paragraph (a)	paragraph (g).
paragraph (b)	paragraph (h).
paragraph (c)	paragraph (i).
paragraph (d)	paragraph (j).
paragraph (e)	paragraph (k).
paragraph (f)	paragraph (l).
paragraph (g)	paragraph (m).

Costs of Compliance

There are about 772 airplanes of the affected design in the worldwide fleet. This proposed AD would affect about 215 airplanes of U.S. registry. The new requirements of this proposed AD add no additional economic burden. The current costs for this proposed AD are repeated below for the convenience of affected operators.

The actions that are required by AD 97-26-07 and retained in this proposed AD take about 4 work-hours per airplane, at an average labor rate of $85 per work-hour. Based on these figures, the estimated cost of the currently required actions is $73,100, or $340 per airplane, per inspection cycle.

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
• 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.

§ 39.13

[Amended]

2. The FAA amends § 39.13 by removing Amendment 39-10250 (62 FR 65352, December 12, 1997) and adding the following new AD:

The Boeing Company: Docket No. FAA-2010-1158; Directorate Identifier 2010-NM-125-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by January 28, 2011.

Affected ADs

(b) This AD supersedes AD 97-26-07, Amendment 39-10250.

Applicability

(c) This AD applies to all The Boeing Company Model 747-100, -100B, -100B SUD, -200B, -200C, -200F, -300, -400, -400D, -400F, 747SR, and 747SP series airplanes, certificated in any category.

Subject

(d) Air Transport Association (ATA) of America Code 28: Fuel.

Unsafe Condition

(e) This AD results from fleet information indicating that the repetitive inspection interval in the existing AD is too long because excessive chafing of the sleeving continues to occur much earlier than expected between scheduled inspections. The Federal Aviation Administration is issuing this AD to detect and correct abrasion of the Teflon sleeving and wires in the bundles of the fuel boost pumps for the numbers 1 and 4 main fuel tanks and of the auxiliary tank jettison pumps (if installed), which could result in electrical arcing between the wires and aluminum conduit and consequent fire or explosion of the fuel tank.

Compliance

(f) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Restatement of Requirements of AD 96-26-06, Amendment 39-9870

Inspections/Repair or Replace if Necessary

(g) Perform an initial inspection to detect damage of the sleeving and wire bundles of the forward and aft boost pumps of the numbers 1 and 4 main fuel tanks, and of the wire bundles of the auxiliary tank jettison pumps (if installed), in accordance with Boeing Service Bulletin 747-28A2204, dated December 19, 1996, or Revision 1, dated October 30, 1997; or Boeing Alert Service Bulletin 747-28A2204, Revision 3, dated March 11, 2010, at the time specified in paragraph (g)(1) or (g)(2) of this AD, as applicable. After the effective date of this AD, only Revision 3 of Boeing Alert Service Bulletin 747-28A2204 may be used.

(1) For airplanes having line numbers 001 through 432 inclusive: Inspect within 120 days after January 21, 1997 (the effective date of AD 96-26-06, amendment 39-9870, which was superseded by AD 97-26-07).

(2) For airplanes having line numbers 433 and subsequent: Inspect at the later of the times specified in paragraphs (g)(2)(i) or (g)(2)(ii) of this AD.

(i) Prior to the accumulation of 20,000 flight cycles or 60,000 flight hours, whichever occurs first; or

(ii) Within 120 days after December 29, 1997 (the effective date of AD 97-26-07).

(h) Repeat the inspection required by paragraph (g) of this AD at intervals not to exceed 20,000 flight cycles or 60,000 flight hours since the last inspection, whichever occurs first, until the first inspection required by paragraph (n) of this AD has been accomplished.

(i) If any damaged sleeving is found, prior to further flight, replace the sleeving with new sleeving, in accordance with Boeing Service Bulletin 747-28A2204, dated December 19, 1996, or Revision 1, dated October 30, 1997; or Boeing Alert Service Bulletin 747-28A2204, Revision 3, dated March 11, 2010. After the effective date of this AD, only Revision 3 of Boeing Alert Service Bulletin 747-28A2204 may be used.

(j) If any damaged wire is found, prior to further flight, repair or replace the wire with a new wire, in accordance with Boeing Service Bulletin 747-28A2204, dated December 19, 1996, or Revision 1, dated October 30, 1997; or Boeing Alert Service Bulletin 747-28A2204, Revision 3, dated March 11, 2010. After the effective date of this AD, only Revision 3 of Boeing Alert Service Bulletin 747-28A2204 may be used.

(k) If any burned wire is found, prior to further flight, perform an inspection to detect damage of the conduit, in accordance with Boeing Service Bulletin 747-28A2204, dated December 19, 1996, or Revision 1, dated October 30, 1997; or Boeing Alert Service Bulletin 747-28A2204, Revision 3, dated March 11, 2010. If any damage is found, prior to further flight, replace the conduit with a serviceable conduit, in accordance with Boeing Service Bulletin 747-28A2204, dated December 19, 1996, or Revision 1, dated October 30, 1997; or Boeing Alert Service Bulletin 747-28A2204, Revision 3, dated March 11, 2010. After the effective date of this AD, only Revision 3 of Boeing Alert Service Bulletin 747-28A2204 may be used.

(l) For airplanes having line numbers 433 and subsequent: Within 14 days after accomplishing the initial inspection required by paragraph (g) of this AD, submit a report of any damaged sleeving (i.e., holes, breaks, cuts, splits), damaged wire (i.e., worn or cracked insulation, exposed conductor, indication of arcing/burning), or damaged conduit to the Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, WA 98057-3356; fax [phone]. The report shall include the information specified in paragraphs (l)(1), (l)(2), (l)(3), (l)(4), and (l)(5) of this AD. Information collection requirements contained in this regulation have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-0056.

(1) The airplane serial number.

(2) The total hours' time-in-service accumulated on the airplane.

(3) The total number of flight cycles accumulated on the airplane.

(4) A description of any damage found.

(5) The location of where the damaged part was installed.

(m) For airplanes having line numbers 433 and subsequent: Within 14 days after accomplishing the initial inspection required by paragraph (g) of this AD, submit any damaged part to the Manager, Seattle ACO. The damaged part shall be tagged to include the information specified in paragraphs (l)(1), (l)(2), (l)(3), (l)(4), and (l)(5) of this AD. Additionally, operators shall align the inner sleeving, outer sleeving, and wire as installed in the airplane, and secure the sleeving and wiring in place by taping or other means when submitting the damaged part to the Manager, Seattle ACO. Information collection requirements contained in this regulation have been approved by the OMB under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq .) and have been assigned OMB Control Number 2120-0056.

New Reduced Inspection Intervals

Repetitive Inspections

(n) Do the next inspection required by paragraph (h) of this AD at the time specified in paragraph (n)(1) or (n)(2) of this AD, as applicable, in accordance with Boeing Alert Service Bulletin 747-28A2204, Revision 3, dated March 11, 2010. Repeat the inspection thereafter at intervals not to exceed 15,000 flight hours. Accomplishing the initial inspection in this paragraph ends the repetitive inspection requirements of paragraph (h) of this AD.

(1) For airplanes on which the inspection required by paragraph (g) of this AD has been done as of the effective date of this AD: Do the inspection at the earlier of the times specified in paragraph (n)(1)(i) and (n)(1)(ii) of this AD.

(i) Within 15,000 flight hours after the most recent inspection, or within 6,000 flight hours after the effective date of this AD, whichever occurs later.

(ii) Within 20,000 flight cycles or 60,000 flight hours after the most recent inspection required by paragraph (g) or (h) of this AD, whichever occurs first.

(2) For airplanes on which the inspection required by paragraph (g) of this AD has not been done as of the effective date of this AD: Do the inspection before the accumulation of 15,000 total flight hours, or within 6,000 flight hours after the effective date of this AD, whichever occurs later.

Paperwork Reduction Act Burden Statement

(o) A federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to a penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a current valid OMB Control Number. The OMB Control Number for this information collection is 2120-0056. Public reporting for this collection of information is estimated to be approximately 5 minutes per response, including the time for reviewing instructions, completing and reviewing the collection of information. All responses to this collection of information are mandatory. Comments concerning the accuracy of this burden and suggestions for reducing the burden should be directed to the FAA at: 800 Independence Ave., SW., Washington, DC 20591, Attn: Information Collection Clearance Officer, AES-200.

Alternative Methods of Compliance (AMOCs)

(p)(1) The Manager, Seattle ACO, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Jon Regimbal, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone]. Information may be e-mailed to: [e-mail].

(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 principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office. The AMOC approval letter must specifically reference this AD.

(3) AMOCs approved previously in accordance with AD 97-26-07, Amendment 39-10250, are approved as alternative methods of compliance with the corresponding requirements of this AD. Compliance time extensions approved previously in accordance with AD 97-26-07, are not approved as alternative methods of compliance for the compliance times required by paragraph (n) of this AD.

Issued in Renton, Washington, on November 15, 2010.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.