[Federal Register: January 2, 2008 (Volume 73, Number 1)]
[Proposed Rules]
[Page 73-75]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr02ja08-16]
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Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2007-28348; Directorate Identifier 2007-NM-060-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-600, -700, -700C, -800
and -900 Series Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Supplemental notice of proposed rulemaking (NPRM); reopening of
comment period.
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SUMMARY: The FAA is revising an earlier proposed airworthiness
directive (AD) for certain Boeing Model 737-600, -700, -700C, -800 and
-900 series airplanes. The original NPRM would have required sealing
the fasteners on the front and rear spars inside the main fuel tank and
on the lower panel of the center fuel tank, inspecting the wire bundle
support installation in the equipment cooling system bays to identify
the type of clamp installed and determine whether the Teflon sleeve is
installed, and doing related corrective actions if necessary. The
original NPRM resulted from a design review of the fuel tank systems.
This action revises the compliance time for the corrective actions
specified in the original NPRM. We are proposing this supplemental NPRM
to prevent arcing at certain fuel tank fasteners in the event of a
lightning strike or fault current event, which, in combination with
flammable fuel vapors, could result in a fuel tank explosion and
consequent loss of the airplane.
DATES: We must receive comments on this supplemental NPRM by January
28, 2008.
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: 202-493-2251.
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 AD, contact Boeing
Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.
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 800-647-5527) is in the
ADDRESSES section. Comments will be available in the AD docket shortly
after receipt.
FOR FURTHER INFORMATION CONTACT: Kathrine Rask, Aerospace Engineer,
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification
Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone
(425) 917-6505; fax (425) 917-6590.
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-2007-
28348; Directorate Identifier 2007-NM-060-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
We proposed to amend 14 CFR part 39 with a notice of proposed
rulemaking (NPRM) for an AD (the ``original NPRM'') for certain Boeing
Model 737-600, -700, -700C, -800 and -900 series airplanes. The
original NPRM was published in the Federal Registeron June 5, 2007 (72
FR 30996). The original NPRM proposed to require sealing the fasteners
on the front and rear spars inside the main fuel tank and on the lower
panel of the center fuel tank, inspecting the wire bundle support
installation in the equipment cooling system bays to identify the type
of clamp installed and determine whether the Teflon sleeve is
installed, and doing related corrective actions if necessary.
Actions Since Original NPRM Was Issued
Since we issued the original NPRM, we have become aware that the
compliance time for the corrective actions in the referenced service
bulletin, Boeing Alert Service Bulletin 737-57A1279, dated January 24,
2007, is specified incorrectly. Paragraph 1.E. of the service bulletin
specifies replacing incorrect clamps within 5 years of the release date
on the service bulletin. Paragraph (g) of this supplemental NPRM would
require this action before further flight after discovery of the
incorrect clamps.
Comments
We provided the public the opportunity to participate in the
development of this AD. We have considered the comments received.
Support for the NPRM
Boeing concurs with the contents of the NPRM.
Request To Revise Compliance Time
Air Transport Association (ATA), on behalf of its member American
Airlines (AAL), requests that we revise the proposed compliance time
for the sealant application and inspection from 60 months to 72 months.
AAL states that its current maintenance schedule might not allow for
accomplishment of the proposed actions on all of its
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affected airplanes within 60 months. AAL would therefore incur
significant costs associated with special maintenance visits to meet
the compliance time.
We disagree with the request. In developing an appropriate
compliance time for this action, we considered the safety implications,
the manufacturer's recommendations, and normal maintenance schedules
for most affected operators for the timely accomplishment of the
required actions. We have determined that the compliance time, as
proposed, represents the maximum interval of time allowable for the
affected airplanes to continue to safely operate before the required
actions are done. We have not changed the original NPRM regarding this
issue. However, according to the provisions of paragraph (h) of this
supplemental NPRM, we may approve requests to adjust the compliance
time if the request includes data that prove that a different
compliance time would provide an acceptable level of safety.
Request To Approve Alternative Part Numbers and Other Specifications
ATA and AAL request that we revise the original NPRM to allow
alternatives to parts and other specifications identified in Alert
Service Bulletin 737-57A1279. AAL states that including an option to
choose among multiple vendors or specifications should reduce any part
availability issues for the operator.
We disagree with the request. We understand that, when developing
service information, Boeing tries to identify alternative parts and
other specifications to give operators as many options as possible. We
review those options when we approve the service information. AAL did
not make any specific proposals for alternative specifications. We need
to approve the use of all such substitutions to ensure that the unsafe
condition is adequately addressed. We have not changed this
supplemental NPRM regarding this issue. However, paragraph (h) of this
supplemental NPRM provides operators the opportunity to request
alternative methods of compliance if data are presented that prove that
the proposed options will provide an acceptable level of safety.
Request To Revise Cost Estimate
ATA and AAL request that we revise the proposed cost estimate to
reflect additional work that might be necessary to comply with the
proposed AD. First, AAL states that the original NPRM provides no costs
for open/close actions, although the proposed actions might not always
be accomplished at the same time as other maintenance work that
involves similar open/close actions (removing A/C packs, opening wing
fuel tanks, and deploying Krueger Flaps). To ensure timely compliance,
AAL suggests that an additional 42.5 hours per airplane might be
necessary for open/close actions. Second, AAL states that the NPRM
provides no costs for clamp/sleeve replacement, although an additional
58 hours per airplane might be necessary for this action (depending on
the inspection results).
We disagree with the request to revise the cost estimate. 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, or the costs of ``on-
condition'' actions such as repairs (that is, actions needed to correct
an unsafe condition). We have not changed the supplemental NPRM
regarding this issue.
FAA's Determination and Proposed Requirements of the Supplemental NPRM
The compliance time for one of the corrective actions discussed
above expands the scope of the original NPRM; therefore, we have
determined that it is necessary to reopen the comment period to provide
additional opportunity for public comment on this supplemental NPRM.
Differences Between the Supplemental NPRM and the Service Bulletin
As stated previously, where the service bulletin specifies a
compliance time for replacing incorrect clamps within 5 years after the
date on the service bulletin, this supplemental NPRM would require this
action before further flight after discovery of the incorrect clamps.
Costs of Compliance
There are about 1,754 airplanes of the affected design in the
worldwide fleet; of these, 645 airplanes are U.S. registered. The
following table provides the estimated costs for U.S. operators to
comply with this supplemental NPRM, at an average hourly labor rate of
$80.
Estimated Costs
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Average Number of U.S.-
Action Group Work hours hourly labor Cost per registered Fleet cost
rate airplane airplanes
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Sealant application..................................... 1 62 $80 $4,960 586 $2,906,560
2 28 80 2,240 44 98,560
3 28 80 2,240 15 33,600
Inspection.............................................. 1 3 80 240 586 140,640
2 3 80 240 44 10,560
3 2 80 160 15 2,400
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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
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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 supplemental NPRM 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, 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.
Sec. 39.13 [Amended]
2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by
adding the following new airworthiness directive (AD):
Boeing: Docket No. FAA-2007-28348; Directorate Identifier 2007-NM-
060-AD.
Comments Due Date
(a) The FAA must receive comments on this AD action by January
28, 2008.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Model 737-600, -700, -700C, -800 and -900
series airplanes, certificated in any category; as identified in
Boeing Alert Service Bulletin 737-57A1279, dated January 24, 2007.
Unsafe Condition
(d) This AD results from a design review of the fuel tank
systems. We are issuing this AD to prevent arcing at certain fuel
tank fasteners in the event of a lightning strike or fault current
event, which, in combination with flammable fuel vapors, could
result in a fuel tank explosion and consequent loss of the airplane.
Compliance
(e) You are responsible for having the actions required by this
AD performed within the compliance times specified, unless the
actions have already been done.
Fastener Sealant
(f) Within 60 months after the effective date of this AD: Seal
the fasteners on the front and rear spars inside the main fuel tank
and on the lower panel of the center fuel tank, as applicable, in
accordance with the Accomplishment Instructions of Boeing Alert
Service Bulletin 737-57A1279, dated January 24, 2007.
Inspection
(g) Within 60 months after the effective date of this AD:
Perform a general visual inspection of the wire bundle support
installation in the equipment cooling system bays to identify the
type of clamp installed, and determine whether the Teflon sleeve is
installed. Do these actions in accordance with the Accomplishment
Instructions of Boeing Alert Service Bulletin 737-57A1279, dated
January 24, 2007. Do all applicable corrective actions before
further flight in accordance with the service bulletin.
Alternative Methods of Compliance (AMOCs)
(h)(1) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, has the authority to approve AMOCs for this AD, if requested in
accordance with the procedures found in 14 CFR 39.19.
(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 appropriate principal inspector (PI) in the FAA
Flight Standards District Office (FSDO), or lacking a PI, your local
FSDO.
Issued in Renton, Washington, on December 20, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E7-25477 Filed 12-31-07; 8:45 am]
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