[Federal Register: February 8, 2006 (Volume 71, Number 26)]
[Proposed Rules]
[Page 6417-6420]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr08fe06-30]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2006-23815; Directorate Identifier 2005-NM-222-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737 Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking.
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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for all Boeing Model 737 airplanes. This proposed AD would require
repetitive measurement of the freeplay of both
[[Page 6418]]
aileron balance tabs; repetitive lubrication of the aileron balance tab
hinge bearings and rod end bearings; and related investigative and
corrective actions if necessary. This proposed AD results from reports
of freeplay-induced vibration of the aileron balance tab. The potential
for vibration of the control surface should be avoided because the
point of transition from vibration to divergent flutter is unknown. We
are proposing this AD to prevent excessive vibration of the airframe
during flight, which could result in loss of control of the airplane.
DATES: We must receive comments on this proposed AD by March 27, 2006.
ADDRESSES: Use one of the following addresses to submit comments on
this proposed AD.
DOT Docket Web site: Go to http://dms.dot.gov and follow
the instructions for sending your comments electronically.
Government-wide rulemaking Web site: Go to http://www.regulations.gov
and follow the instructions for sending your
comments electronically.
Mail: Docket Management Facility, U.S. Department of
Transportation, 400 Seventh Street SW., Nassif Building, room PL-401,
Washington, DC 20590.
Fax: (202) 493-2251.
Hand Delivery: Room PL-401 on the plaza level of the
Nassif Building, 400 Seventh Street SW., Washington, DC, between 9 a.m.
and 5 p.m., Monday through Friday, except Federal holidays.
Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle,
Washington 98124-2207, for the service information identified in this
proposed AD.
FOR FURTHER INFORMATION CONTACT: Dennis Stremick, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425)
917-6450; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to submit any relevant written data, views, or
arguments regarding this proposed AD. Send your comments to an address
listed in the ADDRESSES section. Include the docket number ``FAA-2006-
23815; Directorate Identifier 2005-NM-222-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of the proposed AD. We will
consider all comments received by the closing date and may amend the
proposed AD in light of those comments.
We will post all comments we receive, without change, to http://dms.dot.gov
, including any personal information you provide. We will
also post a report summarizing each substantive verbal contact with FAA
personnel concerning this proposed AD. Using the search function of
that web site, anyone can find and read the comments in any of our
dockets, including the name of the individual who sent the comment (or
signed the comment on behalf of an association, business, labor union,
etc.). You may review DOT's complete Privacy Act Statement in the
Federal Register published on April 11, 2000 (65 FR 19477-78), or you
may visit http://dms.dot.gov.
Examining the Docket
You may examine the AD docket on the Internet at http://dms.dot.gov
, or in person at the Docket Management Facility office
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The Docket Management Facility office (telephone (800) 647-
5227) is located on the plaza level of the Nassif Building at the DOT
street address stated in the ADDRESSES section. Comments will be
available in the AD docket shortly after the Docket Management System
receives them.
Discussion
We have received three reports of freeplay-induced vibration of the
aileron balance tab on Boeing Model 737 airplanes. Excessive corrosion
and wear of components and/or interfaces allows excessive freeplay
movement of the control surfaces and can cause excessive vibration of
the airframe during flight. The potential for vibration of the control
surface should be avoided because the point of transition from
vibration to divergent flutter is unknown. When divergent flutter
occurs, the amplitude of each cycle or oscillation is larger than the
previous one and the surface can quickly reach its structural limits.
Excessive vibration of the airframe, if not corrected, could result in
loss of control of the airplane.
Relevant Service Information
We have reviewed the following Boeing service bulletins:
For Boeing Model 737-100, -200, -200C, -300, -400, -500
series airplanes: Boeing Special Attention Service Bulletin 737-27-
1272, dated September 29, 2005.
For Boeing Model 737-600, -700, -700C, -800 and -900
series airplanes: Boeing Special Attention Service Bulletin 737-27-
1273, dated September 29, 2005.
The service bulletins describe procedures for repetitive
measurement of the freeplay of both aileron balance tabs. If the
freeplay exceeds certain specified limits, the service bulletins
describe procedures for doing applicable related investigative and
corrective actions. These related investigative and corrective actions
include doing a visual inspection for wear of the affected components
such as bearings, bolts, and bushings; and repairing or replacing the
affected part if necessary. The corrective actions also include
repeating the freeplay measurement and applicable related investigative
and corrective actions until the freeplay is within acceptable limits.
The service bulletins also describe procedures for repetitive
lubrication of the aileron balance tab hinge bearings and rod end
bearings. The service bulletins note that if the freeplay measurement
and a lubrication cycle are due at the same time, the freeplay
measurement must be satisfactory before the lubrication is done.
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 previously.
Costs of Compliance
There are about 5,651 airplanes of the affected design in the
worldwide fleet. The following table provides the estimated costs for
U.S. operators to comply with this proposed AD. No parts are necessary
to accomplish either action.
[[Page 6419]]
Estimated Costs
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Number of
Average Cost per airplane U.S.-
Action Work hours labor rate $ registered Fleet cost $
per hour $ airplanes
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Freeplay measurement............ 8 65 520, per 2,280 1,185,600, per
measurement cycle. measurement
cycle.
Lubrication..................... 4 65 260, per 2,280 592,800, per
lubrication cycle. lubrication
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 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-2006-23815; Directorate Identifier 2005-NM-
222-AD.
Comments Due Date
(a) The FAA must receive comments on this AD action by March 27,
2006.
Affected ADs
(b) None.
Applicability
(c) This AD applies to all Boeing Model 737-100, -200, -200C, -
300, -400, -500, -600, -700, -700C, -800, and -900 series airplanes;
certificated in any category.
Unsafe Condition
(d) This AD results from three reports of freeplay-induced
vibration of the aileron balance tab. The potential for vibration of
the control surface should be avoided because the point of
transition from vibration to divergent flutter is unknown. We are
issuing this AD to prevent excessive vibration of the airframe
during flight, which could result in loss of control 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.
Service Bulletin References
(f) The term ``service bulletin,'' as used in this AD, means the
Accomplishment Instructions of the following service bulletins, as
applicable:
(1) For Boeing Model 737-100, -200, -200C, -300, -400, -500
series airplanes: Boeing Special Attention Service Bulletin 737-27-
1272, dated September 29, 2005.
(2) For Boeing Model 737-600, -700, -700C, -800 and -900 series
airplanes: Boeing Special Attention Service Bulletin 737-27-1273,
dated September 29, 2005.
Repetitive Measurements
(g) Within 18 months after the effective date of this AD:
Measure the freeplay of both aileron control balance tabs. Repeat
the measurement thereafter at the applicable interval in paragraph
(g)(1) or (g)(2) of this AD. Do all actions required by this
paragraph in accordance with the applicable service bulletin.
(1) For Boeing Model 737-100, -200, and -200C series airplanes:
At intervals not to exceed 6,000 flight hours or 24 months,
whichever occurs first.
(2) For Boeing Model 737-300, -400, -500, -600, -700, -700C, -
800 and -900 series airplanes: At intervals not to exceed 8,000
flight hours or 24 months, whichever occurs first.
Related Investigative and Corrective Actions
(h) If any measurement found in paragraph (g) of this AD is
outside the acceptable limits specified in the service bulletin:
Before further flight, do the applicable related investigative and
corrective actions in accordance with the applicable service
bulletin.
Repetitive Lubrication
(i) Within 9 months after the effective date of this AD:
Lubricate the aileron balance tab components specified in the
applicable service bulletin. Repeat the lubrication thereafter at
the applicable interval in paragraph (i)(1), (i)(2), or (i)(3) of
this AD. Do all actions required by this paragraph in accordance
with the applicable service bulletin.
(1) For Boeing Model 737-100, -200, and -200C series airplanes:
At intervals not to exceed 3,000 flight hours or 9 months, whichever
occurs first.
(2) For Boeing Model 737-300, -400, -500, -600, -700, -700C, -
800, and -900 series airplanes, on which BMS 3-33 grease is not
used: At intervals not to exceed 3,000 flight hours or 9 months,
whichever occurs first.
(3) For Boeing Model 737-300, -400, -500, -600, -700, -700C, -
800, and -900 series airplanes, on which BMS 3-33 grease is used: At
intervals not to exceed 4,000 flight hours or 12 months, whichever
occurs first.
Concurrent Repetitive Cycles
(j) If a freeplay measurement required by paragraph (g) of this
AD and a lubrication cycle required by paragraph (i) of this AD are
[[Page 6420]]
due at the same time or will be accomplished during the same
maintenance visit, the freeplay measurement and applicable related
investigative and corrective actions must be done before the
lubrication is accomplished.
Alternative Methods of Compliance (AMOCs)
(k)(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) Before using any AMOC approved in accordance with Sec.
39.19 on any airplane to which the AMOC applies, notify the
appropriate principal inspector in the FAA Flight Standards
Certificate Holding District Office.
(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 January 30, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E6-1687 Filed 2-7-06; 8:45 am]
BILLING CODE 4910-13-P