[Federal Register: October 8, 2008 (Volume 73, Number 196)]
[Proposed Rules]
[Page 58906-58908]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr08oc08-27]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2008-1070; Directorate Identifier 2008-NM-087-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-100, -200, -200C, -
300, -400, and -500 Series Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: We propose to adopt a new airworthiness directive (AD) for all
Boeing Model 737-100, -200, -200C, -300, -400, and -500 series
airplanes. For all airplanes, this proposed AD would require repetitive
overhaul of the retract actuator beam of the main landing gear (MLG).
For certain airplanes, this proposed AD would require repetitive
inspections for damage of the retract actuator beam, and related
investigative and corrective actions if necessary. This proposed AD
results from reports of broken retract actuator beams of the MLG and
the subsequent failure of the MLG to fully retract. We are proposing
this AD to detect and correct broken retract actuator beams of the MLG,
which could cause damage to the beam arm, hydraulic tubing, and flight
control cables. Damage to the flight control cables could result in
loss of control of the airplane.
DATES: We must receive comments on this proposed AD by November 24,
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: Nancy Marsh, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425)
917-6440; 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-2008-1070;
Directorate Identifier 2008-NM-087-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 of broken retract actuator beams of the
main landing gear (MLG) and the subsequent failure of the MLG to fully
retract. In one incident, hydraulic system A became unserviceable. In
another incident, the flightcrew declared an emergency and made an air
turn-back. For all the reports of MLG retract actuator beams that broke
in service, the MLG fell to the down-and-locked position, and landings
were normal. Investigation revealed that proper procedures were not
followed during overhaul, resulting in stress corrosion cracking
initiating from small corrosion pits that were not entirely removed. In
one incident, cracking initiated in an area of heat damage/burning
caused by incorrect stylus cadmium plating. Broken retract actuator
beams of the MLG, if not corrected, could cause damage to the beam arm,
hydraulic tubing, and flight control cables. Damage to the flight
control cables could result in loss of control of the airplane.
Relevant Service Information
We have reviewed Boeing Service Bulletin 737-32A1355, Revision 2,
dated March 5, 2008. The service bulletin describes the procedures and
compliance times specified in the following service information table.
[[Page 58907]]
Service Information
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Applicability description Actions Compliance time
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All airplanes.................... An overhaul of the beam is performed Within 180 days after the date of
and improved finishes are applied. this service bulletin, or within 10
New fittings, bushings and bearings years from the date of the most
are installed. The lubrication recent overhaul of the beam,
passages must be cleared. The related whichever occurs later. Repeat
investigative and corrective actions, interval is not to exceed 10 years
if necessary, include a special after the last overhaul.
detailed inspection for corrosion
pits or damage of the beam, and
repair before further flight.
Group 1, Configuration 3 A general visual inspection (GVI) of Within 2 years after the date of this
airplanes with a MLG retract the beam is performed for damage, service bulletin. Repeat interval is
actuator beam having part number finish degradation, and corrosion. not to exceed 2 years after the last
(P/N) 65-46108-14 and previous The related investigative and inspection.
dash numbers that have not corrective actions, if necessary,
incorporated the original issue, include a special detailed inspection
Revision 1, or Revision 2 of the for corrosion pits or damage of the
service bulletin. beam, and repair before further
flight.
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FAA's Determination and Requirements of This Proposed AD
We are proposing this AD because we evaluated all relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other products of the same type design.
This proposed AD would require accomplishing the actions specified in
the service information described previously, except as discussed under
``Differences Between the Proposed AD and Service Information.''
Differences Between the Proposed AD and Service Information
Boeing Service Bulletin 737-32A1355, Revision 2, dated March 5,
2008, does not specify a compliance time for repairing the retract
actuator beam if damage, finish degradation, or corrosion is found.
This proposed AD would require that those repairs be done before
further flight after accomplishing the applicable inspections.
Boeing Service Bulletin 737-32A1355, Revision 2, dated March 5,
2008, specifies that the actions are for airplanes with new MLG retract
actuator beams having P/N 65-46108-15 and subsequent dash numbers that
have not been overhauled, and new or overhauled MLG retract actuator
beams having P/N 65-46108-14 and previous dash numbers. However, MLG
retract actuator beams which are not new or overhauled may also exhibit
the identified unsafe condition. For this reason, this proposed AD is
not limited to new or overhauled beams; the proposed AD would require
that the actions be done on airplanes having any MLG retract actuator
beam having one of those P/Ns. This correction will be included in the
next revision of the service bulletin.
We have coordinated these differences with the manufacturer.
Costs of Compliance
We estimate that this proposed AD would affect 652 airplanes of
U.S. registry. The following table provides the estimated costs for
U.S. operators to comply with this proposed AD.
Estimated Costs
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Number of U.S.-
Action/airplane group Work hours Average labor Parts cost Cost per product registered Fleet cost
rate per hour airplanes
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Overhaul for Group 1; Configurations 64 $80 None.................... $5,120, per overhaul 652 $3,338,240
1, 2, and 3. cycle.
Inspection for Group 1, Configuration 1 80 None.................... $80, per inspection 525 42,000
3. cycle.
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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 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 this 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.
You can find our regulatory evaluation and the estimated costs of
compliance in the AD Docket.
[[Page 58908]]
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 FAA amends Sec. 39.13 by adding the following new AD:
Boeing: Docket No. FAA-2008-1070; Directorate Identifier 2008-NM-
087-AD.
Comments Due Date
(a) We must receive comments by November 24, 2008.
Affected ADs
(b) None.
Applicability
(c) This AD applies to all Boeing Model 737-100, -200, -200C, -
300, -400, and -500 series airplanes, certificated in any category.
Unsafe Condition
(d) This AD results from reports of broken retract actuator
beams of the main landing gear (MLG) and the subsequent failure of
the MLG to fully retract. We are issuing this AD to detect and
correct broken retract actuator beams of the MLG, which could result
in damage to the beam arm, hydraulic tubing, and flight control
cables. Damage to the flight control cables could result in loss of
control of the airplane.
Compliance
(e) Comply with this AD within the compliance times specified,
unless already done.
Inspection and Related Investigative and Corrective Actions/Overhaul
(f) Except as provided by paragraphs (g) and (h) of this AD: At
the applicable times specified in paragraph 1.E. of Boeing Service
Bulletin 737-32A1355, Revision 2, dated March 5, 2008; inspect for
damage of the retract actuator beam of the MLG and overhaul the
retract actuator beam, as applicable, by doing all the applicable
actions specified in the Accomplishment Instructions of the service
bulletin. Do all applicable related investigative and corrective
actions before further flight. Repeat the applicable inspection or
overhaul thereafter at the applicable time specified in paragraph
1.E. of the service bulletin.
Exceptions to Service Information
(g) Where Boeing Service Bulletin 737-32A1355, Revision 2, dated
March 5, 2008, specifies a compliance time after ``* * * the date on
this service bulletin,'' this AD requires compliance within the
specified compliance time after the effective date of this AD.
(h) Boeing Service Bulletin 737-32A1355, Revision 2, dated March
5, 2008, specifies that the actions are for airplanes with new MLG
retract actuator beams that have not been overhauled having P/N 65-
46108-15 and subsequent dash numbers, and new or overhauled MLG
retract actuator beams having P/N 65-46108-14 and previous dash
numbers; however, this AD is not limited to new or overhauled beams.
This AD requires that the actions required by paragraph (f) of this
AD be done on airplanes with any MLG retract actuator beam having
those P/Ns.
Alternative Methods of Compliance (AMOCs)
(i)(1) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, ATTN: Nancy Marsh, Aerospace Engineer, Airframe Branch, ANM-
120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue,
SW., Renton, Washington 98057-3356; telephone (425) 917-6440; fax
(425) 917-6590; has the authority to approve AMOCs for this AD, if
requested using 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.
(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 September 26, 2008.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E8-23828 Filed 10-7-08; 8:45 am]
BILLING CODE 4910-13-P