AD 2001-24-32

[Federal Register Volume 66, Number 239 (Wednesday, December 12, 2001)]
[Rules and Regulations]
[Pages 64100-64102]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 01-30208]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-220-AD; Amendment 39-12549; AD 2001-24-32]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-100, 747-200B, 747-
200C, 747-200F, 747SP, and 747SR Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Boeing Model 747-100, 747-200B, 747-200C, 747-
200F, 747SP, and 747SR series airplanes. This AD requires a one-time 
inspection for chafing of certain wire bundles behind the flight 
engineer's panel; repairs, if necessary; and a modification to reroute 
a certain electrical wire bundle to ensure sufficient clearance between 
that wire bundle and an adjacent flood light support bracket. This 
action is necessary to prevent chafing of certain electrical wire 
bundles, which could result in smoke in the cockpit, and uncommanded 
discharge of fire extinguishing bottles for the No. 4 engine and 
consequent reduction of the ability to fight a fire in the No. 4 
engine. This action is intended to address the identified unsafe 
condition.

DATES: Effective January 16, 2002.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of January 16, 2002.

ADDRESSES: 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 Federal 
Aviation Administration (FAA), Transport Airplane Directorate, Rules 
Docket, 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: Stephen Oshiro, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-
4056; telephone (425) 227-2793; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to

[[Page 64101]]

include an airworthiness directive (AD) that is applicable to certain 
Boeing Model 747-100, 747-200B, 747-200C, 747-200F, 747SP, and 747SR 
series airplanes was published in the Federal Register on July 23, 2001 
(66 FR 38214). That action proposed to require a one-time inspection 
for chafing of certain wire bundles behind the flight engineer's panel; 
repairs, if necessary; and a modification to reroute a certain 
electrical wire bundle to ensure sufficient clearance between that wire 
bundle and an adjacent flood light support bracket.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the single comment received.

Request To Exclude Modified Airplanes

    The commenter requests that the FAA revise the proposed rule to 
state that airplanes modified according to the original issue of Boeing 
Service Bulletin 747-25-2407, dated November 18, 1977, are not subject 
to the inspection specified in paragraph (a) of this AD. The commenter 
notes that it performed the modification in that service bulletin on 
its fleet of Model 747 series airplanes more than 20 years ago.
    The FAA does not concur with the commenter's request. The original 
issue of the referenced service bulletin does not contain procedures 
for an inspection for chafing of affected wire bundles, or repair of 
chafed wire bundles. We find these actions are necessary to ensure that 
any chafed wire bundles are found and fixed. Therefore, airplanes 
modified according to the original issue of the service bulletin are 
still subject to the inspection and any necessary corrective actions 
described in Revision 1 of the service bulletin, dated September 23, 
1999, as required by paragraphs (a) and (a)(1) of this AD.
    Since the issuance of the proposed AD, however, the FAA has 
reviewed the modification procedures in the original issue of the 
service bulletin and determined that those procedures are acceptable 
for accomplishing the modification required by paragraph (a)(2) of this 
AD. Therefore, a new Note 3 has been added to this AD (and subsequent 
notes reordered accordingly) to specify that modifications accomplished 
prior to the effective date of this AD according to the original issue 
of the service bulletin are considered acceptable for compliance with 
paragraph (a)(2) of this AD, but the inspection required by paragraph 
(a) and any applicable corrective actions required by paragraph (a)(1) 
of this AD must still be accomplished.

Explanation of Change to Applicability Statement

    The applicability statement of the proposed AD specified that the 
proposed AD would apply to certain airplane models as listed in Boeing 
Alert Service Bulletin 747-25A2407, Revision 1, dated September 23, 
1999. For the convenience of affected operators, we have revised the 
applicability statement of this AD to specify the line numbers of 
airplanes subject to this AD.

Conclusion

    After careful review of the available data, including the comment 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes previously 
described. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.

Cost Impact

    There are approximately 217 Model 747-100, 747-200B, 747-200C, 747-
200F, 747SP, and 747SR series airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 108 airplanes of U.S. registry 
will be affected by this AD, that it will take approximately 12 work 
hours per airplane to accomplish the required actions, and that the 
average labor rate is $60 per work hour. The cost of required parts per 
airplane will be negligible. Based on these figures, the cost impact of 
this AD on U.S. operators is estimated to be $77,760, or $720 per 
airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the requirements of this AD 
action, and that no operator would accomplish those actions in the 
future if this AD were not adopted. The cost impact figures discussed 
in AD rulemaking actions represent only the time necessary to perform 
the specific actions actually required by the AD. These figures 
typically do not include incidental costs, such as the time required to 
gain access and close up, planning time, or time necessitated by other 
administrative actions.

Regulatory Impact

    The regulations adopted herein will 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. Therefore, it 
is determined that this final rule does not have federalism 
implications under Executive Order 13132.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under 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. A final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it 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 adding the following new 
airworthiness directive:

2001-24-32  Boeing: Amendment 39-12549. Docket 2001-NM-220-AD.

    Applicability: Model 747-100, 747-200B, 747-200C, 747-200F, 
747SP, and 747SR series airplanes; line numbers 001 through 310 
inclusive; 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 (c) 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.


[[Page 64102]]


    Compliance: Required as indicated, unless accomplished previously.
    To prevent chafing of certain electrical wire bundles located 
behind the flight engineer's panel, which could result in smoke in the 
cockpit, and uncommanded discharge of fire extinguishing bottles for 
the No. 4 engine and consequent reduction of the ability to fight a 
fire in the No. 4 engine, accomplish the following:

One-Time Inspection and Modification

    (a) Within 12 months after the effective date of this AD, perform a 
one-time detailed visual inspection for chafing of wire bundles in the 
area of the forward upper corner of the P4 flight engineer's panel, 
outboard of the drip shield. Pay particular attention to wire bundles 
W528 and W530.
    (1) If any chafing is found, before further flight, repair the 
chafed wire bundles according to Section 20-10-13 of the Boeing 
Standard Wiring Practices Manual, and do paragraph (a)(2) of this AD.
    (2) If no chafing is found, or after chafing has been repaired, 
before further flight, modify the airplane by rerouting electrical wire 
bundle W530 to ensure sufficient clearance between that wire bundle and 
an adjacent flood light support bracket and installing a caterpillar 
grommet on the flood light supports, according to Boeing Alert Service 
Bulletin 747-25A2407, Revision 1, dated September 23, 1999.

    Note 2: For the purposes of this AD, a detailed visual 
inspection is defined as: ``An intensive visual examination of a 
specific structural area, system, installation, or assembly to 
detect damage, failure, or irregularity. Available lighting is 
normally supplemented with a direct source of good lighting at 
intensity deemed appropriate by the inspector. Inspection aids such 
as mirror, magnifying lenses, etc., may be used. Surface cleaning 
and elaborate access procedures may be required.''


    Note 3: Modifications accomplished prior to the effective date 
of this AD according to Boeing Service Bulletin 747-25-2407, dated 
November 18, 1977, are considered acceptable for compliance with 
paragraph (a)(2) of this AD. However, the detailed visual inspection 
required by paragraph (a) and any applicable corrective actions 
required by paragraph (a)(1) of this AD must still be accomplished.

Operator's Equivalent Procedure

    (b) Where Boeing Alert Service Bulletin 747-25A2407, Revision 1, 
dated September 23, 1999, specifies that installation of a 
caterpillar grommet may be accomplished per ``your equivalent 
procedure,'' the procedures must be accomplished per the applicable 
chapter of the Boeing 747 Overhaul Manual specified in the service 
bulletin.

Alternative Methods of Compliance

    (c) 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 Aircraft Certification 
Office (ACO), FAA. 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 4: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

Special Flight Permits

    (d) 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.

Incorporation by Reference

    (e) The modification required in paragraph (a)(2) of this AD 
shall be done in accordance with Boeing Alert Service Bulletin 747-
25A2407, Revision 1, dated September 23, 1999. This incorporation by 
reference was approved by the Director of the Federal Register in 
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. 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.

Effective Date

    (f) This amendment becomes effective on January 16, 2002.

    Issued in Renton, Washington, on November 28, 2001.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-30208 Filed 12-11-01; 8:45 am]
BILLING CODE 4910-13-P