AD 2006-21-09
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 777-200 Series | Airworthiness Directives; Boeing Model 777-200 Series Airplanes Equipped with General Electric GE90-94B Engines |
Unsafe Condition
Thrust reversers (TRs) on GE90-94B engines have inner walls that could develop disbonding in the upper bifurcation radii, leading to TR failure and separation from the airplane during flight or a refused takeoff (RTO).
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the identification plate of the torque box on the thrust reversers to determine the part number. Investigate and take corrective actions if necessary, including replacing existing TRs with new or serviceable TRs and marking the service bulletin number on the identification plate.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 50 flight hours after the effective date of the AD.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Boeing Model 777-200 series airplanes equipped with General Electric GE90-94B engines.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 777-200 series airplanes equipped with General Electric GE90-94B engines. This AD requires inspecting to determine the part number of the identification plate of the torque box on the thrust reversers (TRs), and investigative and corrective actions if necessary. This AD results from engine certification testing which revealed that TRs on GE90-94B engines have inner walls that could develop disbonding in the upper bifurcation radii. Disbonding was found in an equivalent inner wall used during the testing. We are issuing this AD to prevent failure of a TR and adjacent components and their consequent separation from the airplane during flight or during a refused takeoff (RTO). These separated components could cause structural damage to the airplane or damage to other airplanes and possible injury to people on the ground. TR failure during a RTO could also cause the engine to produce forward thrust, resulting in asymmetric thrust and possible runway excursion.
Document Text
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[Federal Register Volume 71, Number 202 (Thursday, October 19, 2006)]
[Rules and Regulations]
[Pages 61644-61646]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: E6-17428]
[[Page 61644]]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2006-26085; Directorate Identifier 2006-NM-142-AD;
Amendment 39-14794; AD 2006-21-09]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 777-200 Series Airplanes
Equipped with General Electric GE90-94B Engines
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule; request for comments.
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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain Boeing Model 777-200 series airplanes equipped with General
Electric GE90-94B engines. This AD requires inspecting to determine the
part number of the identification plate of the torque box on the thrust
reversers (TRs), and investigative and corrective actions if necessary.
This AD results from engine certification testing which revealed that
TRs on GE90-94B engines have inner walls that could develop disbonding
in the upper bifurcation radii. Disbonding was found in an equivalent
inner wall used during the testing. We are issuing this AD to prevent
failure of a TR and adjacent components and their consequent separation
from the airplane during flight or during a refused takeoff (RTO).
These separated components could cause structural damage to the
airplane or damage to other airplanes and possible injury to people on
the ground. TR failure during a RTO could also cause the engine to
produce forward thrust, resulting in asymmetric thrust and possible
runway excursion.
DATES: This AD becomes effective November 3, 2006.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in the AD as of November 3,
2006.
We must receive comments on this AD by December 18, 2006.
ADDRESSES: Use one of the following addresses to submit comments on
this AD.
<bullet> DOT Docket Web site: Go to <a href="http://dms.dot.gov">http://dms.dot.gov</a> and follow
the instructions for sending your comments electronically.
<bullet> Government-wide rulemaking Web site: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a> and follow the instructions for sending your
comments electronically.
<bullet> Mail: Docket Management Facility; U.S. Department of
Transportation, 400 Seventh Street SW., Nassif Building, Room PL-401,
Washington, DC 20590.
<bullet> Fax: (202) 493-2251.
<bullet> 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
AD.
FOR FURTHER INFORMATION CONTACT: Gary Oltman, Aerospace Engineer,
Airframe Branch, ANM-120S, Seattle Aircraft Certification Office, FAA,
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425)
917-6443; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Discussion
We have received a report indicating that engine certification
testing on certain Boeing Model 777-200 series airplanes with General
Electric GE90 engines revealed that certain thrust reversers (TRs) have
inner walls that could develop disbonding in the upper bifurcation
radii. Disbonding and structural degradation was found in an equivalent
inner wall used during the testing. Investigation revealed that the
disbonding was caused by a flight maneuver that applied too much stress
in the upper bifurcation radii composite materials. This condition, if
not corrected, could result in failure of a TR and adjacent components
and their consequent separation from the airplane during flight or
during a refused takeoff (RTO). These separated components could cause
structural damage to the airplane or damage to other airplanes and
possible injury to people on the ground. TR failure during a RTO could
also cause the engine to produce forward thrust, resulting in
asymmetric thrust and possible runway excursion.
Relevant Service Information
We have reviewed Boeing Alert Service Bulletin 777-78A0056, dated
April 20, 2006. The service bulletin describes procedures for a general
visual inspection to determine the part number on the identification
plate of the torque box on the TRs, and investigative and corrective
actions if necessary. If the identification plate shows any part number
specified in paragraph 3.B.1.a. of the service bulletin, without the
service bulletin number as a modification number, the investigative and
corrective actions include, among other things, replacing the existing
TRs with new or serviceable TRs, and marking the service bulletin
number on the identification plate of the torque box. Accomplishing the
actions specified in the service information is intended to adequately
address the unsafe condition.
The Boeing service bulletin refers to Spirit AeroSystems Document
MAA7-70023-1, dated November 22, 2005, as an additional source of
service information for accomplishing the corrective actions.
FAA's Determination and Requirements of This AD
The unsafe condition described previously is likely to exist or
develop on other airplanes of the same type design that may be
registered in the U.S. at some time in the future. Therefore, we are
issuing this AD to prevent failure of a TR and adjacent components and
their consequent separation from the airplane during flight or during a
RTO. These separated components could cause structural damage to the
airplane or damage to other airplanes and possible injury to people on
the ground. TR failure during a RTO could also cause the engine to
produce forward thrust, resulting in asymmetric thrust and possible
runway excursion. This AD requires accomplishing the actions specified
in the Boeing service information described previously, except as
discussed under ``Difference Between the AD and the Service
Information.''
Difference Between the AD and the Service Information
You should note that, although Boeing Alert Service Bulletin 777-
78A0056 specifies that you may contact the manufacturer for repair
instructions, this AD requires you to repair in one of the following
ways:
<bullet> Using a method that we approve; or
<bullet> Using data that meet the certification basis of the
airplane that have been approved by an Authorized Representative for
the Boeing Delegation Option Authorization Organization who has been
authorized by the FAA to make those findings.
Costs of Compliance
None of the airplanes affected by this action are on the U.S.
Register. All airplanes affected by this AD are currently operated by
non-U.S. operators under foreign registry; therefore, they are not
directly affected by this AD action. However, we consider this AD
necessary to ensure that the unsafe condition is addressed if any
affected airplane is imported and placed on the U.S. Register in the
future.
[[Page 61645]]
If an affected airplane is imported and placed on the U.S. Register
in the future, the required inspection 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 AD would be $80 per airplane.
FAA's Determination of the Effective Date
No airplane affected by this AD is currently on the U.S. Register.
Therefore, providing notice and opportunity for public comment is
unnecessary before this AD is issued, and this AD may be made effective
in less than 30 days after it is published in the Federal Register.
Comments Invited
This AD is a final rule that involves requirements that affect
flight safety and was not preceded by notice and an opportunity for
public comment; however, we invite you to submit any relevant written
data, views, or arguments regarding this AD. Send your comments to an
address listed under the ADDRESSES section. Include ``Docket No. FAA-
2006-26085; Directorate Identifier 2006-NM-142-AD'' at the beginning of
your comments. We specifically invite comments on the overall
regulatory, economic, environmental, and energy aspects of the AD that
might suggest a need to modify it.
We will post all comments we receive, without change, to <a href="http://dms.dot.gov">http://dms.dot.gov</a>, including any personal information you provide. We will
also post a report summarizing each substantive verbal contact with FAA
personnel concerning this 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 the DOT's complete Privacy Act Statement in the Federal
Register published on April 11, 2000 (65 FR 19477-78), or you may visit
<a href="http://dms.dot.gov">http://dms.dot.gov</a>.
Examining the Docket
You may examine the AD docket on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a>, 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.
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 AD will not have federalism
implications under Executive Order 13132. This AD will 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 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 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, Incorporation by
reference, Safety.
Adoption of the Amendment
0
Accordingly, under the authority delegated to me by the Administrator,
the FAA amends 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
0
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]
0
2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by
adding the following new airworthiness directive (AD):
2006-21-09 Boeing: Amendment 39-14794. Docket No. FAA-2006-26085;
Directorate Identifier 2006-NM-142-AD.
Effective Date
(a) This AD becomes effective November 3, 2006.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Boeing Model 777-200 series airplanes
equipped with General Electric GE90-94B engines; certificated in any
category; as identified in Boeing Alert Service Bulletin 777-
78A0056, dated April 20, 2006.
Unsafe Condition
(d) This AD results from engine certification testing which
revealed that thrust reversers (TRs) on GE90-94B engines have inner
walls that could develop disbonding in the upper bifurcation radii.
Disbonding was found in an equivalent inner wall used during the
testing. We are issuing this AD to prevent failure of a TR and
adjacent components and their consequent separation from the
airplane during flight or during a refused takeoff (RTO). These
separated components could cause structural damage to the airplane
or damage to other airplanes and possible injury to people on the
ground. TR failure during a RTO could also cause the engine to
produce forward thrust, resulting in asymmetric thrust and possible
runway excursion.
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.
General Visual Inspection/Investigative and Corrective Actions
(f) Within 24 months after the effective date of this AD: Do a
general visual inspection to determine the part number of the
identification plate of the torque box on the TRs, and do all
applicable investigative and corrective actions before further
flight, in accordance with the Accomplishment Instructions of Boeing
Alert Service Bulletin 777-78A0056, dated April 20, 2006. If any
discrepancy is found and the service bulletin specifies to contact
Boeing for appropriate action: Before further flight, repair the TR
using a method approved in accordance with the procedures specified
in paragraph (g) of this AD.
[[Page 61646]]
Note 1: The Boeing service bulletin refers to Spirit AeroSystems
Document MAA7-70023-1, dated November 22, 2005, as an additional
source of service information for accomplishing the corrective
actions.
Alternative Methods of Compliance (AMOCs)
(g)(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.
Material Incorporated by Reference
(h) You must use Boeing Alert Service Bulletin 777-78A0056,
dated April 20, 2006, to perform the actions that are required by
this AD, unless the AD specifies otherwise. The Director of the
Federal Register approved the incorporation by reference of this
document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51.
Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle,
Washington 98124-2207, for a copy of this service information. You
may review copies at the Docket Management Facility, U.S. Department
of Transportation, 400 Seventh Street, SW., Room PL-401, Nassif
Building, Washington, DC; on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a>; or
at the National Archives and Records Administration (NARA). For
information on the availability of this material at the NARA, call
(202) 741-6030, or go to <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
Issued in Renton, Washington, on October 10, 2006.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate; Aircraft Certification
Service.
[FR Doc. E6-17428 Filed 10-18-06; 8:45 am]
BILLING CODE 4910-13-P
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Retrieved: Apr 4, 2026
Rights: U.S. Government Public Domain
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