AD 2001-17-20

Recurring final rule

Airworthiness Directives; Boeing Model 707 and 720 Series Airplanes

AD Number
2001-17-20
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 2000-NM-318-AD
FR Citation
66 FR 44954

Applicability

TypeManufacturerModelDetails
aircraft Boeing 707 720 Airworthiness Directives; Boeing Model 707 and 720 Series Airplanes

Unsafe Condition

Damaged wiring for the fuel boost pumps and override pumps could cause electrical arcing, puncturing the conduit and resulting in an explosion or fire adjacent to the fuel tank.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Replace the wiring for the fuel boost pumps and override pumps with new wiring, install Teflon sleeving on the wiring, and perform repetitive inspections to detect wiring damage or fuel leaks. Corrective actions, including finding and repairing fuel leaks, replacing wiring, conduit, or installing new Teflon sleeving, must be taken if electrical arcing, exposed copper wire, or fuel leaks are detected.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within the compliance time specified in the referenced service bulletin, unless accomplished previously.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Boeing Model 707 and 720 series airplanes, line numbers 1 through 941 inclusive, certificated in any category.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 707 and 720 series airplanes, that requires replacement of wiring for the fuel boost pumps and override pumps with new wiring, installation of Teflon sleeving on the wiring, and associated actions. This amendment also requires repetitive inspections to detect damage of the wiring or evidence of a fuel leak. This amendment is necessary to detect and correct damaged wiring for the fuel boost pumps and override pumps, which could cause electrical arcing that could puncture the conduit containing the wire, and result in an explosion or fire adjacent to the fuel tank. This action is intended to address the identified unsafe condition.

Document Text

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[Federal Register Volume 66, Number 166 (Monday, August 27, 2001)]
[Rules and Regulations]
[Pages 44954-44957]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 01-21395]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-318-AD; Amendment 39-12411; AD 2001-17-20]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 707 and 720 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Boeing Model 707 and 720 series airplanes, that 
requires replacement of wiring for the fuel boost pumps and override 
pumps with new

[[Page 44955]]

wiring, installation of Teflon sleeving on the wiring, and associated 
actions. This amendment also requires repetitive inspections to detect 
damage of the wiring or evidence of a fuel leak. This amendment is 
necessary to detect and correct damaged wiring for the fuel boost pumps 
and override pumps, which could cause electrical arcing that could 
puncture the conduit containing the wire, and result in an explosion or 
fire adjacent to the fuel tank. This action is intended to address the 
identified unsafe condition.

DATES: Effective October 1, 2001.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of October 1, 2001.

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: Sulmo Mariano, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone 
(425) 227-2686; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to certain Boeing Model 707 and 720 
series airplanes was published in the Federal Register on March 29, 
2001 (66 FR 17123). That action proposed to require replacement of 
wiring for the fuel boost pumps and override pumps with new wiring, 
installation of Teflon sleeving on the wiring, and associated actions. 
That action also proposed to require repetitive inspections to detect 
damage of the wiring or evidence of a fuel leak.

Comments Received

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. The FAA has duly considered several 
comments received from a single commenter.

Refer to Revised Service Information

    The commenter requests that we revise the proposed rule to 
reference Boeing Service Bulletin A3500, Revision 1, dated April 26, 
2001. (The proposed rule refers to the original issue of Boeing Alert 
Service Bulletin A3500, dated July 27, 2000, as the appropriate source 
of service information for doing the proposed actions.) The commenter 
notes Revision 1 of the service bulletin contains updated information, 
such as changes to part numbers, but necessitates no additional work on 
airplanes modified per the original issue of the service bulletin.
    We concur and have revised paragraphs (a) and (b) of this final 
rule to reference Revision 1 of the service bulletin. We have also 
added a new note, Note 4, which states that accomplishment of the 
actions required by this AD prior to the effective date of this AD 
according to the original issue of the service bulletin is acceptable 
for compliance with this AD.

Refer to Service Bulletin for Rework Instructions

    The commenter requests that we revise paragraph (b) of the proposed 
AD to remove the instructions in that paragraph and instead refer to 
the appropriate section of the Accomplishment Instructions of the 
referenced service bulletin. The commenter states that, as written, 
paragraph (b) would require an operator to replace the wiring, Teflon 
sleeving, and conduit with new parts if a small fuel leak is found, 
even if no evidence of electrical arcing or an exposed conductor is 
found. The commenter notes that the intent of the proposed AD is to 
require replacement of the wiring and sleeving only when there is 
evidence of arcing or an exposed conductor.
    We concur with the commenter's request and rationale. Therefore, we 
have revised paragraph (b) to require, if any electrical arcing or 
exposed copper wire or evidence of a fuel leak is detected during any 
inspection per paragraph (b), accomplishment of applicable corrective 
actions (including finding the source of any fuel leak and repairing 
the affected area, replacing the wiring, replacing the conduit, or 
installing new Teflon sleeving; as applicable) according to the 
Accomplishment Instructions of the service bulletin.

Revise Cost Impact

    The commenter asks that we revise the Cost Impact section of the 
proposed AD to reduce the number of affected U.S.-registered airplanes 
from 65 to 22 airplanes. The commenter states that the airplane 
manufacturer's records show that there are only 22 U.S.-registered 
Boeing Model 707 and 720 series airplanes in service.
    We do not concur. The figure of 22 U.S.-registered airplanes cited 
by the commenter does not include all of the Model 707 series airplanes 
operated by the U.S. military. When these airplanes are included in the 
total, there are 65 U.S. airplanes affected by this AD. No change is 
necessary in this regard.
    The commenter also asks us to revise the Cost Impact section of the 
proposed AD to increase the number of work hours necessary to do the 
required actions from 27 to 38 work hours. The commenter states that 
the referenced service bulletin provides a figure of 38 work hours.
    We partially concur. The figure of 38 work hours in the service 
bulletin includes time for gaining access and closing up. The cost 
impact analysis in AD rulemaking actions typically includes only the 
``direct'' costs of the specific actions required by the AD, and does 
not include incidental costs, such as the time required to gain access 
and close up, planning time, or time necessitated by other 
administrative actions. Because incidental costs may vary significantly 
from operator to operator, they are almost impossible to calculate. 
However, we find that the time needed for testing may be included in 
the cost estimate of this AD. Therefore, the estimate for the number of 
work hours for the required actions stated in the Cost Impact section 
of this final rule has been revised from 27 to 31 work hours.

Conclusion

    After careful review of the available data, including the comments 
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 261 Model 707 and 720 series airplanes of 
the affected design in the worldwide fleet. The FAA estimates that 65 
airplanes of U.S. registry will be affected by this AD.
    The replacement and initial associated actions will take 
approximately 31 work hours per airplane, at the average labor rate of 
$60 per work hour. Based on these figures, the FAA estimates the cost 
impact of these required actions on U.S. operators to be $120,900, or 
$1,860 per airplane.
    The inspection for damage of the wiring or evidence of a fuel leak 
will take approximately 3 work hours per airplane, at the average labor 
rate of $60

[[Page 44956]]

per work hour. Based on these figures, the FAA estimates the cost 
impact of this required inspection on U.S. operators to be $11,700, or 
$180 per airplane, per inspection cycle.
    The cost impact figures discussed above are 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:

2001-17-20  Boeing: Amendment 39-12411. Docket 2000-NM-318-AD.

    Applicability: Model 707 and 720 series airplanes, line numbers 
1 through 941 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.

    Compliance: Required as indicated, unless accomplished 
previously.
    To detect and correct damaged wiring for the fuel boost pumps 
and override pumps, which could cause electrical arcing that could 
puncture the conduit containing the wire and result in an explosion 
or fire adjacent to the fuel tank, accomplish the following:

Replacement of Wiring, Installation of Sleeving, and Associated Actions

    (a) Within 1 year or 4,000 flight hours after the effective date 
of this AD, whichever occurs first, replace the wiring for the fuel 
boost pumps and override pumps, install Teflon sleeving over the 
wiring, and do all associated actions, per the Accomplishment 
Instructions of Boeing Service Bulletin A3500, Revision 1, dated 
April 26, 2001. The associated actions include performing a general 
visual inspection of the area around each fuel boost pump and 
override pump for evidence of a fuel leak; finding the source of any 
fuel leak and repairing the affected area; replacing the conduit, if 
required; and performing a detailed visual inspection of the wiring 
installed in the conduit for evidence of electrical arcing or a fuel 
leak, or exposed copper wire. If replacement of the conduit is 
deferred per the service bulletin, repeat the inspection for fuel 
leaks every 500 flight hours until the conduit is replaced, and 
replace the conduit within 6,000 flight hours or 18 months, 
whichever occurs first.

    Note 2: For the purposes of this AD, a general visual inspection 
is defined as: ``A visual examination of an interior or exterior 
area, installation, or assembly to detect obvious damage, failure, 
or irregularity. This level of inspection is made under normally 
available lighting conditions such as daylight, hangar lighting, 
flashlight, or drop-light, and may require removal or opening of 
access panels or doors. Stands, ladders, or platforms may be 
required to gain proximity to the area being checked.''


    Note 3: 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 4: Use of Boeing Alert Service Bulletin A3500, dated July 
27, 2000, to accomplish the actions required by this AD prior to the 
effective date of this AD is considered acceptable for compliance 
with this AD.

Repetitive Inspections

    (b) After replacement of the wiring per paragraph (a) of this 
AD, repeat the detailed visual inspection of the wiring for the fuel 
boost pumps and override pumps for damage, such as evidence of 
electrical arcing or exposed copper wire, or evidence of a fuel 
leak. Repeat the inspection at least every 30,000 flight hours, per 
the Accomplishment Instructions of Boeing Service Bulletin A3500, 
Revision 1, dated April 26, 2001. If any electrical arcing or 
exposed copper wire or evidence of a fuel leak is detected during 
any inspection per this paragraph, before further flight, do the 
applicable corrective actions (including finding the source of any 
fuel leak and repairing the affected area, replacing the wiring, 
replacing the conduit, or installing new Teflon sleeving; as 
applicable) according to the Accomplishment Instructions of 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 5: 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 actions shall be done in accordance with Boeing Service 
Bulletin A3500, Revision 1, dated April 26, 2001. 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,

[[Page 44957]]

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 October 1, 2001.

    Issued in Renton, Washington, on August 17, 2001.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-21395 Filed 8-24-01; 8:45 am]
BILLING CODE 4910-13-P

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