[Federal Register Volume 62, Number 239 (Friday, December 12, 1997)]
[Rules and Regulations]
[Pages 65352-65355]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-32611]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-295-AD; Amendment 39-10250; AD 97-26-07]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD), applicable to certain Boeing Model 747 series airplanes, that 
currently requires a one-time inspection 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

[[Page 65353]]

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. This amendment requires repetitive inspections in 
lieu of the one-time inspection. This amendment also expands the 
applicability of the existing AD. This amendment is prompted by reports 
of chafing of the sleeving. The actions specified in this AD are 
intended 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.

DATES: Effective December 29, 1997.

    The incorporation by reference of Boeing Service Bulletin 747-
28A2204, Revision 1, dated October 30, 1997, as listed in the 
regulations, is approved by the Director of the Federal Register as of 
December 29, 1997.
    The incorporation by reference of Boeing Alert Service Bulletin 
747-28A2204, dated December 19, 1996, as listed in the regulations, was 
approved previously by the Director of the Federal Register as of 
January 21, 1997 (62 FR 304, January 3, 1997).
    Comments for inclusion in the Rules Docket must be received on or 
before February 10, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 97-NM-295-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056.
    The service information referenced in this AD may be obtained from 
Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 
98124-2207. This information may be examined at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at 
the Office of the Federal Register, 800 North Capitol Street, NW., 
suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Ed Hormel, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Transport Airplane Directorate, 
Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (425) 227-2681; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION: On December 23, 1996, the FAA issued AD 96-
26-06, amendment 39-9870 (62 FR 304, January 3, 1997), applicable to 
certain Boeing Model 747 series airplanes, to require a one-time 
inspection 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 action was prompted by an FAA determination that an 
environment conducive to vibration exists in the conduit and wire 
bundles of the boost pumps and of the auxiliary tank jettison pumps, 
which can cause abrasion of the Teflon sleeving and consequent abrasion 
of the wires in the bundles. The actions required by that AD are 
intended to detect and correct such abrasion, which could result in 
electrical arcing between the wires and the aluminum conduit and 
consequent fire or explosion of the fuel tank.

Actions Since Issuance of Previous Rule

    Since the issuance of AD 96-26-06, the FAA has received numerous 
reports of chafing through the outer Teflon sleeve of the wire bundles 
of the boost pumps of the numbers 1 and 4 main fuel tanks. Several of 
the sleeves had large holes. No cases of wire chafing through the 
insulation to the conductor were reported. Investigation revealed that 
two of the affected operators had varying levels of chafing with damage 
on 48 percent of their airplanes. Both of these operators had replaced 
the aluminum conduits with stainless steel conduits. Other affected 
operators' airplanes (with flight hour totals similar to those of the 
airplanes discussed previously) that were equipped with aluminum 
conduits had a much lower incidence of reported damage.
    At the time of issuance of AD 96-26-06, the FAA considered the 
aluminum conduit to be more susceptible to chafing and burning as a 
result of electrical arcing between the wires and the aluminum conduit 
than the stainless steel conduit. Therefore, the FAA limited the 
inspection required by AD 96-26-06 to Boeing Model 747 series airplanes 
equipped with aluminum conduits (line numbers 001 through 432 
inclusive).
    In light of these new findings, the FAA has determined that Boeing 
Model 747 series airplanes equipped with stainless steel conduits are 
subject to the same unsafe condition addressed in AD 96-26-06. In 
addition, the FAA finds that, regardless of the conduit material, 
repetitive inspections are necessary to determine if the sleeving of 
the wire bundles continues to provide a protective barrier after 
extended time in service.

Explanation of Relevant Service Information

    Additionally, since the issuance of AD 96-26-06, the FAA has 
reviewed and approved Revision 1 of Boeing Service Bulletin 747-
28A2204, dated October 30, 1997. Revision 1 of the service bulletin 
revises the effectivity listing of the original version of the service 
bulletin (which was referenced in AD 96-26-06 as the appropriate source 
of service information) by adding Boeing Model 747 series airplanes 
having line numbers 433 through 1120 inclusive. The inspection and 
corrective procedures described in Revision 1 are essentially identical 
to those described in the original version of the alert service 
bulletin.

Explanation of Requirements of Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of this same type design, this AD 
supersedes AD 96-26-06 to require repetitive inspections, in lieu of 
the previously required one-time inspection, 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, this AD also continues 
to require an inspection to detect damage of the conduit, and 
replacement of any damaged conduit with a serviceable conduit. This AD 
also expands the applicability of the existing AD to include additional 
airplanes. This AD requires that operators submit a report to the FAA 
of any damage found as a result of the initial inspection.

Differences Between the AD and the Relevant Service Information

    Operators should note that the applicability of the AD differs from 
the effectivity listing of Revision 1 of the referenced service 
bulletin. The FAA has determined that all Boeing Model 747 series 
airplanes are subject to the addressed unsafe condition.

Interim Action

    This is considered to be interim action until final action is 
identified, at which time the FAA may consider further rulemaking.

[[Page 65354]]

Determination of Rule's Effective Date

    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this rule by 
submitting such written data, views, or arguments as they may desire. 
Communications shall identify the Rules Docket number and be submitted 
in triplicate to the address specified under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the rule. All comments submitted will be 
available, both before and after the closing date for comments, in the 
Rules Docket for examination by interested persons. A report that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 97-NM-295-AD.'' The postcard will be date stamped and 
returned to the commenter.

Regulatory Impact

    The regulations adopted herein will not have substantial direct 
effects 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. Therefore, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and that it is not a ``significant regulatory 
action'' under Executive Order 12866. It has been determined further 
that this action involves an emergency regulation under DOT Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
determined that this emergency regulation otherwise would be 
significant under DOT Regulatory Policies and Procedures, a final 
regulatory evaluation will be prepared and placed in the Rules Docket. 
A copy of it, if filed, may be obtained from the Rules Docket at the 
location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (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.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-9870 (62 FR 
304, January 3, 1997), and by adding a new airworthiness directive 
(AD), amendment 39-10250, to read as follows:

97-26-07  Boeing: Amendment 39-10250. Docket 97-NM-295-AD. 
Supersedes AD 96-26-06, Amendment 39-9870.

    Applicability: All Model 747 series airplanes, certificated in 
any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (h) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    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, 
accomplish the following:
    (a) 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 Alert Service Bulletin 747-28A2204, dated December 19, 1996, 
or Boeing Service Bulletin 747-28A2204, Revision 1, dated October 
30, 1997, at the time specified in paragraph (a)(1) or (a)(2) of 
this AD, as applicable.
    (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).
    (2) For airplanes having line numbers 433 and subsequent: 
Inspect at the later of the times specified in paragraphs (a)(2)(i) 
and (a)(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 the effective date of this AD.
    (b) Repeat the inspection required by paragraph (a) of this AD 
at intervals not to exceed 20,000 flight cycles or 60,000 flight 
hours since the last inspection, whichever occurs first.
    (c) If any damaged sleeving is found, prior to further flight, 
replace the sleeving with new sleeving in accordance with Boeing 
Alert Service Bulletin 747-28A2204, dated December 19, 1996, or 
Boeing Service Bulletin 747-28A2204, Revision 1, dated October 30, 
1997.
    (d) If any damaged wire is found, prior to further flight, 
repair or replace the wire with a new wire in accordance with Boeing 
Alert Service Bulletin 747-28A2204, dated December 19, 1996, or 
Boeing Service Bulletin 747-28A2204, Revision 1, dated October 30, 
1997.
    (e) If any burned wire is found, prior to further flight, 
perform an inspection to detect damage of the conduit, in accordance 
with Boeing Alert Service Bulletin 747-28A2204, dated December 19, 
1996, or Boeing Service Bulletin 747-28A2204, Revision 1, dated 
October 30, 1997. If any damage is found, prior to further flight, 
replace the conduit with a serviceable conduit in accordance with 
either of the service bulletins. After the effective date of this 
AD, only Revision 1 of this service bulletin shall be used.
    (f) For airplanes having line numbers 433 and subsequent: Within 
14 days after accomplishing the initial inspection required by 
paragraph (a) 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

[[Page 65355]]

Certification Office (ACO), FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, WA 98055-4056; fax (425) 227-1181. 
The report shall include the information specified in paragraphs 
(f)(1), (f)(2), (f)(3), (f)(4), and (f)(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.
    (g) For airplanes having line numbers 433 and subsequent: Within 
14 days after accomplishing the initial inspection required by 
paragraph (a) 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 (f)(1), (f)(2), (f)(3), (f)(4), 
and (f)(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.
    (h) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Seattle ACO. Operators shall submit 
their requests through an appropriate FAA Principal Maintenance 
Inspector, who may add comments and then send it to the Manager, 
Seattle ACO.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

    (i) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the airplane to a location where 
the requirements of this AD can be accomplished.
    (j) The actions shall be done in accordance with Boeing Alert 
Service Bulletin 747-28A2204, dated December 19, 1996, or Boeing 
Service Bulletin 747-28A2204, Revision 1, dated October 30, 1997.
    (1) The incorporation by reference of Boeing Service Bulletin 
747-28A2204, Revision 1, dated October 30, 1997, is approved by the 
Director of the Federal Register in accordance with 5 U.S.C. 552(a) 
and 1 CFR part 51.
    (2) The incorporation by reference of Boeing Alert Service 
Bulletin 747-28A2204, dated December 19, 1996, was approved 
previously by the Director of the Federal Register as of January 21, 
1997 (62 FR 304, January 3, 1997).
    (3) Copies may be obtained from Boeing Commercial Airplane 
Group, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be 
inspected at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
    (k) This amendment becomes effective on December 29, 1997.

    Issued in Renton, Washington, on December 9, 1997.
John J. Hickey,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-32611 Filed 12-11-97; 8:45 am]
BILLING CODE 4910-13-P