[Federal Register: January 31, 2006 (Volume 71, Number 20)]
[Proposed Rules]
[Page 5021-5023]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr31ja06-14]
=======================================================================
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2006-23734; Directorate Identifier 2005-NM-174-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 757 Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Notice of proposed rulemaking (NPRM).
-----------------------------------------------------------------------
SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for certain Boeing Model 757 airplanes. This proposed AD would require
installing a control wheel damper assembly at the first officer's drum
bracket assembly and aileron quadrant beneath the flight deck floor in
section 41; doing a functional test and adjustment of the new
installation; and doing related investigative/corrective actions if
necessary. For certain airplanes, this proposed AD would require doing
an additional adjustment test of the re-located control wheel position
sensor, and an operational test of the flight data recorder and the
digital flight data acquisition unit. This proposed AD also would
require installing vortex generators (vortilons) on the leading edge of
the outboard main flap on certain airplanes. This proposed AD results
from several reports that flightcrews experienced unintended roll
oscillations during final approach, just before landing. We are
proposing this AD to prevent unintended roll oscillations near
touchdown, which could result in loss of directional control of the
airplane, and consequent airplane damage and/or injury to flightcrew
and passengers.
DATES: We must receive comments on this proposed AD by March 17, 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: John Neff, Aerospace Engineer, Flight
Test Branch, ANM-160S, FAA, Seattle Aircraft Certification Office, 1601
Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 917-
6521; 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-
23734; Directorate Identifier 2005-NM-174-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 eleven confirmed reports that flightcrews on
Boeing Model 757 airplanes experienced unintended roll oscillations
during final approach, just before landing. One event resulted in a
nose gear collapse after a hard landing; another event resulted in a
tail strike during a landing that was aborted because of the
oscillations. Of the eleven events that have been confirmed, three
occurred with Flight Test personnel aboard, during flight-testing
activities.
These roll oscillations occur when the pilot makes large, rapid
movements of the control wheel, and the airplane does not respond as
expected. Boeing has developed a damper for the control wheel that
reduces the likelihood of these roll oscillations by providing
resistive force to large, rapid control wheel movements that exceed a
set value.
We have also received flight test data indicating that one
potential cause of these unintended roll oscillations occurs when
airflow over the outboard trailing edge flap separates due to the
movement of the spoilers resulting from large control wheel inputs.
Abrupt control wheel inputs to counteract the resulting roll can lead
to roll oscillations of increasing magnitude. Boeing has developed
vortex generators (vortilons) that create vortices over the flap
surface and help to mitigate a sudden and premature airflow separation
when the flaps are set in landing configuration and the spoilers
forward of the flaps are deployed.
Unintended roll oscillations near touchdown, if not corrected,
could result in loss of directional control of the airplane, and
consequent airplane
[[Page 5022]]
damage and/or injury to flightcrew and passengers.
Relevant Service Information
We have reviewed Boeing Alert Service Bulletin 757-27A0146, dated
October 14, 2004 (for Model 757-200, -200PF, and -200CB series
airplanes); and Boeing Alert Service Bulletin 757-27A0147, dated
October 14, 2004 (for Model 757-300 series airplanes). These service
bulletins describe procedures for installing a control wheel damper
assembly at the first officer's drum bracket assembly and aileron
quadrant beneath the flight deck floor in section 41. This installation
involves adding a new damper, bracket, crank arm, and control rod. The
new damper bracket is installed at four existing holes on the drum
bracket assembly. The service bulletins also describe procedures for
doing a functional test and adjustment of the new installation,
including doing any necessary related investigative and corrective
actions and repeating the test and adjustment until all discrepancies
are corrected. These service bulletins also describe procedures for
sending a report when the applicable service bulletin is complete for
each airplane.
We have also reviewed Boeing Alert Service Bulletin 757-57A0058,
Revision 1, dated January 10, 2002 (for Model 757-200, -200PF and -
200CB series airplanes). This service bulletin describes procedures for
installing vortex generators (vortilons) on the leading edge of the
outboard main flap. The service bulletin specifies that the vortex
generators should be installed on both the left and right flaps at the
same time. Installation of vortex generators on only one flap of an
airplane may adversely affect the airplane's flight characteristics.
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, except as discussed under
``Differences Between the Proposed AD and the Service Bulletins.''
Differences Between the Proposed AD and the Service Bulletins
Boeing Alert Service Bulletin 757-27A0146 and Boeing Alert Service
Bulletin 757-27A0147 specify a compliance time of 36 months for
installing a control wheel damper assembly. Boeing Alert Service
Bulletin 757-57A0058, Revision 1, recommends installing the vortex
generators at the next ``heavy maintenance check.'' This proposed AD
would require doing all the actions within 24 months after the
effective date of the proposed AD. In developing an appropriate
compliance time for this proposed AD, we considered the manufacturer's
recommendation, the degree of urgency associated with the subject
unsafe condition, the probability of future occurrences, and the
average utilization of the affected fleet. In light of all these
factors we find that a 24-month compliance time represents an
appropriate interval of time for affected airplanes to continue to
operate without compromising safety.
Although the Accomplishment Instructions of Boeing Alert Service
Bulletin 757-27A0146 and Boeing Alert Service Bulletin 757-27A0147
describe procedures for submitting a sheet recording accomplishment of
the service bulletin, this proposed AD would not require that action.
Although Boeing Alert Service Bulletin 757-27A0146 and Boeing Alert
Service Bulletin 757-27A0147 specify that operators may contact the
manufacturer if a just-installed (new) wheel damper does not function
properly, this proposed AD would require operators to correct that
condition according to a method approved by the FAA.
These differences have been coordinated with Boeing.
Interim Action
We consider this proposed AD interim action. The manufacturer is
currently investigating an additional modification that may further
reduce or eliminate the unsafe condition identified in this AD. Once
this modification is developed, approved, and available, we may
consider additional rulemaking.
Costs of Compliance
There are about 1,036 airplanes of the affected design in the
worldwide fleet and about 629 U.S.-registered airplanes. The following
table provides the estimated costs for U.S. operators to comply with
this proposed AD. Not all of the required actions must be done on all
U.S.-registered airplanes.
Estimated Costs
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Number of
Average U.S.-
Action Work hours labor rate Parts Cost per airplane registered Fleet cost
per hour airplanes
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Install control wheel damper 9 to 11.............. $65 $7,650 to $10,550................. $8,235 to $11,265................. 578 $4,759,830 to $6,511,170.
assembly, and do functional test
(Model 757-200, -200PF, and -200CB
series airplanes).
Install control wheel damper 15................... 65 $10,550........................... $11,525........................... 51 $587,775.
assembly, and do functional test
(Model 757-300 series airplanes).
Install vortex generators (Model 757- 10................... 65 $3,336............................ $3,986............................ 527 $2,100,622.
200, -200PF, and -200CB series
airplanes).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
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.
[[Page 5023]]
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-2006-23734; Directorate Identifier 2005-NM-
174-AD.
Comments Due Date
(a) The FAA must receive comments on this AD action by March 17,
2006.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Model 757-200, -200PF, -200CB, and -300
series airplanes, certificated in any category; as identified in the
applicable service bulletin or bulletins in Table 1 of this AD.
Table 1.--Boeing Service Bulletins
----------------------------------------------------------------------------------------------------------------
Boeing Alert Service Bulletin Revision Date Model
----------------------------------------------------------------------------------------------------------------
757-27A0146.......................... Original.............. October 14, 2004........ 757-200, -200PF, and -
200CB.
757-27A0147.......................... Original.............. October 14, 2004........ 757-300 series
airplanes.
757-57A0058.......................... 1..................... January 10, 2002........ 757-200, -200PF, and -
200CB.
----------------------------------------------------------------------------------------------------------------
Unsafe Condition
(d) This AD results from several reports that flightcrews
experienced unintended roll oscillations during final approach, just
before landing. We are issuing this AD to prevent unintended roll
oscillations near touchdown, which could result in loss of
directional control of the airplane, and consequent airplane damage
and/or injury to flightcrew and passengers.
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.
Installations
(f) Within 24 months after the effective date of this AD, do the
actions in paragraphs (f)(1) and (f)(2) of this AD, as applicable.
(1) For all airplanes: Install a control wheel damper assembly
at the first officer's drum bracket assembly and aileron quadrant
beneath the flight deck floor in section 41; and do all applicable
functional and operational tests and adjustments of the new
installation, and all applicable related investigative/corrective
actions before further flight after the installation. Do all actions
in accordance with the Accomplishment Instructions of Boeing Alert
Service Bulletin 757-27A0146, dated October 14, 2004 (for Model 757-
200, -200PF, and -200CB series airplanes); and Boeing Alert Service
Bulletin 757-27A0147, dated October 14, 2004 (for Model 757-300
series airplanes).
(2) For Model 757-200, -200PF, and -200CB series airplanes:
Install vortex generators (vortilons) on the leading edge of the
outboard main flap in accordance with the Accomplishment
Instructions of Boeing Alert Service Bulletin 757-57A0058, Revision
1, dated January 10, 2002.
Parts Installation
(g) As of the effective date of this AD, no person may install a
damper bracket assembly part number (P/N) 251N1432-2, a bracket-
sensor P/N 251N1430-2, or a crank arm P/N 251N1431-2, on any
airplane.
Actions Accomplished in Accordance With Previous Revision of Service
Bulletin
(h) Actions done before the effective date of this AD in
accordance with Boeing Special Attention Service Bulletin 757-57-
0058, dated March 9, 2000, are acceptable for compliance with the
actions in paragraph (f)(2) of this AD.
No Reporting Required
(i) Although the Accomplishment Instructions of Boeing Alert
Service Bulletin 757-27A0146 and Boeing Alert Service Bulletin 757-
27A0147 describe procedures for submitting a sheet recording
accomplishment of the service bulletin, this AD does not require
that action.
Alternative Methods of Compliance (AMOCs)
(j)(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.
Issued in Renton, Washington, on January 11, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E6-1188 Filed 1-30-06; 8:45 am]
BILLING CODE 4910-13-P