AD 2006-21-09

final rule

Airworthiness Directives; Boeing Model 777-200 Series Airplanes Equipped with General Electric GE90-94B Engines

AD Number
2006-21-09
Status
final_rule
Effective Date
Product Category
engine
Docket
Docket No. FAA-2006-26085
FR Citation
71 FR 61644

Applicability

TypeManufacturerModelDetails
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

Show stored source text (verify against official source)
[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.

-----------------------------------------------------------------------

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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