[Federal Register Volume 68, Number 3 (Monday, January 6, 2003)]
[Rules and Regulations]
[Pages 481-483]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-17]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NM-44-AD; Amendment 39-13006; AD 2002-26-18]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-600, -700, -700C, -
800, and -900 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 737-600, -700, -700C, -800, and -900 
series airplanes, that requires replacement of the existing fueling 
float switch and conduit assemblies in the main and center fuel tanks 
with new, improved assemblies. The actions specified by this AD are 
intended to prevent fluid contamination inside the fueling float switch 
or chafing of the wiring to the in-tank conduit, which could generate 
an ignition source and consequent fire and explosion in the fuel tank. 
This action is intended to address the identified unsafe condition.

DATES: Effective February 10, 2003.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of February 10, 2003.

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: Doug Pegors, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone 
(425) 227-1446; 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 737-600, -
700, -700C, -800, and -900 series airplanes was published in the 
Federal Register on August 20, 2002 (67 FR 53893). That action proposed 
to require replacement of the existing fueling float switch and conduit 
assemblies in the main and center fuel tanks with new, improved 
assemblies.

Comments

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

Request To Add Revised Service Information

    One commenter, the manufacturer, asks that Boeing Alert Service 
Bulletin 737-28A1142, Revision 2, dated November 26, 2002, be added to 
the proposed AD as another source of service information for 
accomplishment of the specified actions. Boeing Alert Service Bulletin 
737-28A1142, dated February 7, 2002, was referenced in the proposed AD 
as the appropriate source of service information for accomplishment of 
the actions.
    The FAA agrees with the commenter. We have reviewed and approved 
Boeing Alert Service Bulletin 737-28A1142, Revision 2, dated November 
26, 2002.

[[Page 482]]

We find that the changes incorporated in Revision 2 of the service 
bulletin are not substantive, meaning that airplanes modified per the 
original issue of the service bulletin are not subject to any 
additional work under Revision 2 of the service bulletin. Therefore, we 
have revised paragraph (a) of this final rule to refer to Revision 2 of 
the service bulletin as the appropriate source of service information 
for the actions in that paragraph. In addition, we have added a new 
paragraph (b) to this final rule (and reordered subsequent paragraphs 
accordingly) to give credit for replacements accomplished before the 
effective date of this AD according to the original issue of the 
service bulletin.

Request To Change Number of Airplanes Affected

    The same commenter asks that the number of affected airplanes that 
is specified in the Cost Impact section of the proposed AD be changed. 
The commenter provided supporting data which confirms that the number 
of airplanes in the worldwide fleet is 927, and the number of U.S.-
registered airplanes is 421.
    We agree with the commenter, as we inadvertently specified the 
incorrect numbers of affected airplanes in the proposed AD. We have 
changed the Cost Impact section in this final rule to reflect the 
correct numbers of airplanes.

Request To Change Work Hours

    One commenter states that the man hours specified in the Cost 
Impact section of the proposed AD are conservative, and notes that the 
actual man hours will be higher and will increase the out-of-service 
time for its airplanes.
    Although the commenter does not request a change, we infer that the 
commenter would like the number of work hours specified in the Cost 
Impact section to be increased.
    We do not agree to change the work hours for the replacements. The 
number of work hours necessary to accomplish the replacements, as 
specified in the Cost Impact section, is consistent with the service 
bulletin. The number represents the time necessary to perform only the 
replacements actually required by this AD. We recognize that, in 
accomplishing the requirements of any AD, operators may incur 
``incidental'' costs in addition to the ``direct'' costs. The cost 
analysis in AD rulemaking actions, however, typically 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. Therefore, no 
change is made to the final rule in this regard.

Explanation of Change to Final Rule

    We have changed the compliance time terminology specified in 
paragraphs (a)(1), (a)(2), and (a)(3) of the proposed AD from flight 
cycles to flight hours in the final rule. We inadvertently used the 
term ``flight cycles,'' in the proposed AD; however, the referenced 
service bulletin specifies ``flight hours,'' and the proposed AD also 
should have specified ``flight hours.''

Conclusion

    After careful review of the available data, we have determined that 
air safety and the public interest require the adoption of the rule 
with the changes previously described. We have 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 927 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 421 airplane of U.S. registry 
will be affected by this AD.
    It will take approximately 56 work hours per airplane to accomplish 
the replacement in the two main fuel tanks, as specified in Work Page 
I, at an average labor rate of $60 per work hour. Based on these 
figures, the cost impact of the work hours for this required 
replacement on U.S. operators is estimated to be $1,414,560, or $3,360 
per airplane.
    It will take approximately 23 work hours per airplane to accomplish 
the replacement in the center fuel tank, as specified in Work Package 
II, at an average labor rate of $60 per work hour. Based on these 
figures, the cost impact of the work hours per this required 
replacement on U.S. operators is estimated to be $580,980, or $1,380 
per airplane.
    The kit required to accomplish the replacement in all three fuel 
tanks will cost approximately $5,116 per airplane.
    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:

2002-26-18 Boeing: Amendment 39-13006. Docket 2002-NM-44-AD.

    Applicability: Model 737-600, -700, -700C, -800, and -900 series 
airplanes; certificated in any category; as listed in Boeing Alert 
Service Bulletin 737-28A1142, Revision 2, dated November 26, 2002.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability

[[Page 483]]

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 prevent fluid contamination inside the fueling float switch 
or changing of the wiring to the in-tank conduit, which could 
generate an ignition source and consequent fire and explosion in the 
fuel tank, accomplish the following:

Replacement

    (a) Replace the existing fueling float switch and conduit 
assemblies in the main and center fuel tanks with new, improved 
assemblies (includes a new float switch and a new conduit assembly 
with a liner system inside the conduit), at the applicable time 
specified in paragraph (a)(1), (a)(2), or (a)(3) of this AD, per 
Work Packages I and II of the Accomplishment Instructions of Boeing 
Alert Service Bulletin 737-28A1142, Revision 2, dated November 26, 
2002.

    Note 2: Due to the lack of sleeving on the existing electrical 
wire installations of the center fuel tank, it is recommended that 
Work Package II be completed before Work Package I.

    (1) For airplanes that have accumulated fewer than 5,000 total 
flight hours as of the effective date of this AD: Within 2 years 
after the effective date of this AD.
    (2) For airplanes that have accumulated 5,000 total flight hours 
or more, but fewer than 10,000 total flight hours as of the 
effective date of this AD: Within 1 year after the effective date of 
this AD.
    (3) For airplanes that have accumulated 10,000 total flight 
hours or more as of the effective date of this AD: Within 180 days 
after the effective date of this AD.
    (b) Replacements done before the effective date of this AD per 
Boeing Alert Service Bulletin 737-28A1142, dated February 7, 2002, 
are considered acceptable for compliance with paragraph (a) of this 
AD.

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, Transport Airport Directorate. 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 3: 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 requests of this AD can be accomplished.

Incorporation by Reference

    (e) Unless otherwise specified in this AD, the replacement shall 
be done in accordance with Boeing Alert Service Bulletin 737-
28A1142, Revision 2, dated November 26, 2002. 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 February 10, 2003.

    Issued in Renton, Washington, on December 26, 2002.
Charles D. Huber,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 03-17 Filed 1-3-03; 8:45 am]
BILLING CODE 4910-13-P