[Federal Register: November 19, 2007 (Volume 72, Number 222)]
[Proposed Rules]
[Page 64955-64957]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr19no07-14]
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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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[[Page 64955]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2007-0202; Directorate Identifier 2007-NM-185-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-600, 737-700, 737-
700C, 737-800, and 737-900 Series Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for certain Boeing Model 737-600, 737-700, 737-700C, 737-800, and 737-
900 series airplanes. This proposed AD would require an inspection of
the vertical fin lugs, skin, and skin edges for discrepancies, an
inspection of the flight control cables, fittings, and pulleys in
section 48 for signs of corrosion, an inspection of the horizontal
stabilizer jackscrew, ball nut, and gimbal pins for signs of corrosion,
and corrective actions if necessary. This proposed AD results from
reports indicating that moisture was found within the section 48
cavity. We are proposing this AD to ensure that the correct amount of
sealant was applied around the vertical fin lugs, skin and the skin
edges. Missing sealant could result in icing of the elevator cables,
which could cause a system jam and corrosion of structural and flight
control parts, resulting in reduced controllability of the airplane.
DATES: We must receive comments on this proposed AD by January 3, 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: Wayne Lockett, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425)
917-6447; 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-2007-0202;
Directorate Identifier 2007-NM-185-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 have received reports indicating that moisture was found within
the section 48 cavity on Boeing Model 737-600, 737-700, 737-700C, 737-
800, and 737-900 series airplanes. A root-cause investigation
determined that, due to a manufacturing process error, airplanes were
delivered with an incorrect amount of sealant around the station (STA)
1088 vertical fin lugs common to the section 48 skin. This condition,
if not corrected, could result in icing of the elevator cables, which
could cause a system jam and corrosion of structural and flight control
parts, resulting in reduced controllability of the airplane.
Relevant Service Information
We have reviewed Boeing Service Bulletin 737-53A1242, Revision 2,
dated April 23, 2007. The service bulletin describes the following
procedures:
Inspecting the vertical fin lugs, skin, and skin edges for
discrepancies (i.e. water ingress, corrosion damage, and missing,
insufficient, or cracked sealant).
Performing a detailed inspection of the flight control
cables, fittings, and pulleys in section 48 for signs of corrosion.
Performing a detailed inspection of the horizontal
stabilizer jackscrew, ball nut, and gimbal pins for signs of corrosion.
Performing applicable corrective actions. The corrective
actions include repairing cracks, filling the space between the
vertical fin lugs and skin, lubricating the horizontal stabilizer trim
actuator and actuator gimbal pins, replacing any cracked sealant with a
new sealant, and contacting Boeing for corrosion repair conditions, as
applicable.
Accomplishing the actions specified in the service information is
intended to adequately address the unsafe condition.
FAA's Determination and Requirements of the Proposed AD
We have evaluated all pertinent information and identified an
unsafe condition that is likely to exist or develop on other airplanes
of this same type design. For this reason, we are proposing this AD,
which would require accomplishing the actions specified in the service
information described
[[Page 64956]]
previously, except as discussed under ``Difference Between the Proposed
AD and Service Bulletin.''
Difference Between the Proposed AD and Service Bulletin
In this proposed AD, the ``inspection'' and ``visual inspection''
specified in the Boeing service bulletin is referred to as a ``detailed
inspection.'' We have included the definition for a detailed inspection
in a note in the proposed AD.
The service bulletin specifies to contact the manufacturer for
instructions on how to repair certain conditions, but this proposed AD
would require repairing those conditions in one of the following ways:
Using a method that we approve; or
Using data that meet the certification basis of the
airplane, and that have been approved by an Authorized Representative
for the Boeing Commercial Airplanes Delegation Option Authorization
Organization whom we have authorized to make those findings.
Costs of Compliance
There are about 829 airplanes of the affected design in the
worldwide fleet. This proposed AD would affect about 372 airplanes of
U.S. registry. The proposed actions would take about 1 work hour per
airplane, at an average labor rate of $80 per work hour. Based on these
figures, the estimated cost of the proposed AD for U.S. operators is
$29,760, or $80 per airplane.
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 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 proposed AD 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-2007-0202; Directorate Identifier 2007-NM-
185-AD.
Comments Due Date
(a) The FAA must receive comments on this AD action by January
3, 2008.
Affected ADs
(b) None.
Applicability
(c) This AD applies to certain Boeing Model 737-600, 737-700,
737-700C, 737-800, and 737-900 series airplanes, certificated in any
category; as identified in Boeing Service Bulletin 737-53A1242,
Revision 2, dated April 23, 2007.
Unsafe Condition
(d) This AD results from reports indicating that moisture was
found within the section 48 cavity. We are issuing this AD to ensure
that the correct amount of sealant was applied around the vertical
fin lugs, skin and the skin edges. Missing sealant could result in
icing of the elevator cables, which could cause a system jam and
corrosion of structural and flight control parts, resulting in
reduced controllability 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.
Inspections
(f) Within 2,500 flight cycles or 18 months after the effective
date of this AD, whichever occurs first, do the detailed inspections
specified in paragraphs (f)(1), (f)(2) and (f)(3) of this AD in
accordance with the Accomplishment Instructions of the Boeing
Service Bulletin 737-53A1242, Revision 2, dated April 23, 2007.
(1) Do a detailed inspection of the vertical fin lugs, skin, and
skin edges for discrepancies (i.e. water ingress, corrosion damage,
and missing, insufficient, or cracked sealant).
(2) Do a detailed inspection of the flight control cables,
fittings, and pulleys in section 48 for signs of corrosion.
(3) Do a detailed inspection of the horizontal stabilizer
jackscrew, ball nut, and gimbal pins for signs of corrosion.
Note 1: For the purposes of this AD, a detailed inspection is:
``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 (i.e., the person performing the inspection).
Inspection aids such as mirror, magnifying lenses, etc., may be
used. Surface cleaning and elaborate access procedures may be
required.''
Corrective Actions
(g) If any discrepancy or corrosion is found during any
inspection required by paragraph (f) of this AD, before further
flight, do the applicable corrective actions in accordance with the
Accomplishment Instructions of Boeing Service Bulletin 737-53A1242,
Revision 2, dated April 23, 2007; except where the service bulletin
specifies to contact Boeing, repair using a method approved in
accordance with the procedures specified in paragraph (i) of this
AD.
Credit for Actions Done Using the Previous Service Information
(h) Actions accomplished before the effective date of this AD in
accordance with Boeing Service Bulletin 737-53A1242, dated October
17, 2002; and Revision 1, dated April 28, 2005; are considered
acceptable for compliance with the corresponding actions specified
in paragraphs (f) and (g) of this AD.
Alternative Methods of Compliance (AMOCs)
(i)(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.
[[Page 64957]]
(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.
(3) An AMOC that provides an acceptable level of safety may be
used for any repair required by this AD, if it is approved by an
Authorized Representative for the Boeing Commercial Airplanes
Delegation Option Authorization Organization who has been authorized
by the Manager, Seattle ACO, to make those findings. For a repair
method to be approved, the repair must meet the certification basis
of the airplane, and the approval must specifically refer to this
AD.
Issued in Renton, Washington, on November 7, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E7-22548 Filed 11-16-07; 8:45 am]
BILLING CODE 4910-13-P