AD 2001-16-03

[Federal Register Volume 66, Number 151 (Monday, August 6, 2001)]
[Rules and Regulations]
[Pages 40880-40883]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 01-19385]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-137-AD; Amendment 39-12371; AD 2001-16-03]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 767-200, -300, -300F, and 
-400ER Series Airplanes Equipped with General Electric Model CF6-80C2 
Series Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to certain Boeing Model 767-200, -300, -300F, and -400ER 
series airplanes equipped with General Electric Model CF6-80C2 series 
engines. This action requires various repetitive inspections and tests 
of certain fail-safe features of the thrust reverser control system; 
and corrective actions, if necessary. This action is necessary to 
ensure that the fail-safe features of the thrust reverser are fully 
functional and to protect against an in-flight thrust reverser 
deployment, which could result in loss of controllability of the 
airplane. This action is intended to address the identified unsafe 
condition.

DATES: Effective August 21, 2001.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of August 21, 2001.
    Comments for inclusion in the Rules Docket must be received on or 
before October 5, 2001.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport

[[Page 40881]]

Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-137-
AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may 
be inspected at this location between 9:00 a.m. and 3:00 p.m., Monday 
through Friday, except Federal holidays. Comments may be submitted via 
fax to (425) 227-1232. Comments may also be sent via the Internet using 
the following address: <a href="/cdn-cgi/l/email-protection#073e2a66696a2a6e667564686a6a6269734761666629606871"><span class="__cf_email__" data-cfemail="20190d414e4d0d494152434f4d4d454e54604641410e474f56">[email&#160;protected]</span></a>. Comments sent via fax 
or the Internet must contain ``Docket No. 2001-NM-137-AD'' in the 
subject line and need not be submitted in triplicate. Comments sent via 
the Internet as attached electronic files must be formatted in 
Microsoft Word 97 for Windows or ASCII text.
    The service information referenced in this AD may be obtained from 
Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 
98124-2207. This information may be examined at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at 
the Office of the Federal Register, 800 North Capitol Street, NW., 
suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Dennis Kammers, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone 
(425) 227-2956; fax (425) 227-5210.

SUPPLEMENTARY INFORMATION: The FAA has received numerous reports of 
failures of the flexshaft of the thrust reverser actuation system 
(TRAS) lock (also known as electro-mechanical brake) between the upper 
actuator and the TRAS lock on Boeing Model 767-200, -300, -300F, and -
400ER series airplanes equipped with General Electric Model CF6-80C2 
series engines. These failures were detected during operational checks 
required by paragraph (f) of AD 2000-09-04, amendment 39-11712 (65 FR 
25833, May 4, 2000) (described further below). The TRAS lock provides a 
fail-safe level of protection against in-flight deployment of the 
thrust reverser by retaining the thrust reverser drive shaft. 
Investigation revealed that when the flexshaft fails, the TRAS lock 
cannot retain the thrust reverser drive shaft and is effectively 
removed from the thrust reverser system. There is no airplane system to 
detect this failure and the cause is unknown at this time. This 
condition, if not corrected, could result in the loss of the fail-safe 
level of protection against an in-flight thrust reverser deployment. 
Such a loss increases the risk of an in-flight thrust reverser 
deployment, which could result in loss of controllability of the 
airplane.

Other Relevant Rulemaking

    The FAA has previously issued AD 2000-09-04, which requires tests, 
inspections, and adjustments of the thrust reverser on Boeing Model 767 
series airplanes equipped with General Electric Model CF6-80C2 series 
engines. That AD also requires installation of a terminating 
modification, and repetitive follow-on actions. The tests and 
inspections of the TRAS lock (electro-mechanical brake) required by 
paragraph (f) of that AD were intended to detect and correct latent 
failures of the TRAS lock. Because of the numerous reports above, we 
find that further rulemaking action is necessary to address the 
identified unsafe condition. However, this AD will not affect the 
current requirements of AD 2000-09-04.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
767-78A0090, Revision 1, dated July 5, 2001 (for Model 767-200, -300, 
and -300F series airplanes), and Boeing Alert Service Bulletin 767-
78A0091, Revision 1, dated July 5, 2001 (for Model 767-400ER series 
airplanes). The service bulletins describe the following procedures:
    1. Repetitive general visual inspections of the bullnose seal to 
detect discrepancies (i.e., wear, tears, cracks, missing segments, and 
improper folds, as applicable) and assess damage; and replacement of 
the bullnose seal with a new bullnose seal, if necessary.
    2. Repetitive tests of the electrical connector P3/P4 of the left 
and right position switch modules of the center drive unit (CDU) of the 
thrust reverser for electrical continuity (0.50 ohms or less) between 
pins 3 and 4 and between pins 5 and 6; and replacement of the left and 
right position switch modules with new modules, if necessary.
    3. Repetitive ``hot short'' protection tests to verify that the 
resistance between pins 1 and 2 of each connector of the TRAS lock on 
the left and right engines is 4.0 ohms or less; and corrective actions 
(i.e., additional testing, replacement of the relay, and troubleshoot 
the connecting wires; as applicable), if necessary.
    4. Repetitive ``hot short'' protection tests to verify that the 
resistance between pins 1 and 2 of connection P5 of the directional 
pilot valve (DPV) is 4.0 ohms or less, and corrective actions, if 
necessary.
    In addition, the FAA has reviewed and approved Boeing Alert Service 
Bulletin 767-78A0081, Revision 2, dated April 19, 2001 (for Model 767-
200, -300, and -300F series airplanes), and Boeing Alert Service 
Bulletin 767-78A0088, dated April 19, 2001 (for Model 767-400ER series 
airplanes). These service bulletins describe procedures for a 
functional test on both thrust reversers for the electro-mechanical 
brakes (i.e., TRAS locks) and CDU cone brakes of both engines to verify 
proper holding torque; and corrective actions, if necessary. The 
corrective actions involve ensuring proper torque, installing or 
replacing components with new components, and performing additional 
inspections; as applicable.

Explanation of the Requirements of the Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other Boeing Model 767-200, -300, -300F, and -400ER 
series airplanes equipped with General Electric Model CF6-80C2 series 
engines of the same type design, this AD is being issued to ensure that 
the fail-safe features of the thrust reverser are fully functional and 
to protect against an in-flight thrust reverser deployment, which could 
result in loss of controllability of the airplane. This AD requires 
accomplishment of the actions specified in the applicable service 
bulletins described previously, except as discussed below.

Differences Between the Service Bulletins and AD

    The 767 Master Minimum Equipment List (MMEL) allows the thrust 
reverser under certain conditions, to be deactivated for up to 10 days; 
however, it does not describe procedures for accomplishment of such a 
task. The deactivation procedures are described in Section 2-78-31-1 of 
Boeing Document D630T002, ``Boeing 767 Dispatch Deviation Guide,'' 
Revision 20, dated August 18, 2000. Therefore, the FAA finds that, in 
lieu of certain corrective actions described in Boeing Alert Service 
Bulletin 767-78A0090, Revision 1, dated July 5, 2001 (for Model 767-
200, -300, and -300F series airplanes), and Boeing Alert Service 
Bulletin 767-78A0091, Revision 1, dated July 5, 2001 (for Model 767-
400ER series airplanes), the thrust reverser may be deactivated per the 
MMEL for up to 10 days provided that the following actions are done:
    1. Before further flight, the deactivation is done per Section 2-
78-31-1 of Boeing Document D630T002,

[[Page 40882]]

``Boeing 767 Dispatch Deviation Guide,'' Revision 20, dated August 18, 
2000;
    2. Within 10 days following accomplishment of the deactivation, the 
applicable corrective action(s) specified in paragraph (b) of this AD 
are done; and
    3. Before further flight following accomplishment of the applicable 
corrective action(s), the thrust reverser is reactivated.
    We find that accomplishment of the optional deactivation procedures 
above for up to 10 days is acceptable for affected airplanes to 
continue to operate without compromising safety.
    Operators should note that, although Boeing Alert Service Bulletin 
767-78A0081, Revision 2, dated April 19, 2001 (for Model 767-200, -300, 
and -300F series airplanes), and Boeing Alert Service Bulletin 767-
78A0088, dated April 19, 2001 (for Model 767-400ER series airplanes), 
recommend accomplishing the functional test on both thrust reversers 
for the electro-mechanical brakes (i.e., TRAS lock) and CDU cone brakes 
of both engines within 650 flight hours (after the receipt of the 
service bulletin), the FAA has determined that an interval of 650 
flight hours would not address the identified unsafe condition in a 
timely manner. In developing an appropriate compliance time for this 
proposed AD, the FAA considered not only the manufacturer's 
recommendation, but the degree of urgency associated with addressing 
the subject unsafe condition, as well as the numerous reports of 
failures of the flexshaft of the TRAS lock (described above). In light 
of all of these factors, we find that accomplishing the functional test 
prior to installation of a General Electric Model CF6-80C2 engine to be 
warranted, in that it represents an appropriate interval of time 
allowable for affected airplanes to continue to operate without 
compromising safety.

Interim Action

    This is considered to be interim action until final action is 
identified, at which time the FAA may consider further rulemaking.

Determination of Rule's Effective Date

    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this rule by 
submitting such written data, views, or arguments as they may desire. 
Communications shall identify the Rules Docket number and be submitted 
in triplicate to the address specified under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Submit comments using the following format:
    <bullet> Organize comments issue-by-issue. For example, discuss a 
request to change the compliance time and a request to change the 
service bulletin reference as two separate issues.
    <bullet> For each issue, state what specific change to the AD is 
being requested.
    <bullet> Include justification (e.g., reasons or data) for each 
request.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the rule. All comments submitted will be 
available, both before and after the closing date for comments, in the 
Rules Docket for examination by interested persons. A report that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2001-NM-137-AD.'' The postcard will be date stamped 
and returned to the commenter.

Regulatory Impact

    The regulations adopted herein 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. Therefore, it 
is determined that this final rule does not have federalism 
implications under Executive Order 13132.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and that it is not a ``significant regulatory 
action'' under Executive Order 12866. It has been determined further 
that this action involves an emergency regulation under DOT Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
determined that this emergency regulation otherwise would be 
significant under DOT Regulatory Policies and Procedures, a final 
regulatory evaluation will be prepared and placed in the Rules Docket. 
A copy of it, if filed, may be obtained from the Rules Docket at the 
location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (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. Section 39.13 is amended by adding the following new 
airworthiness directive:

2001-16-03  Boeing: Amendment 39-12371. Docket 2001-NM-137-AD.

    Applicability: Model 767-200, -300, -300F, and -400ER series 
airplanes, equipped with General Electric Model CF6-80C2 series 
engines; certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (e) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To ensure that the fail-safe features of the thrust reverser are 
fully functional and to protect against an in-flight thrust reverser 
deployment, which could result in loss of

[[Page 40883]]

controllability of the airplane, accomplish the following:

    Note 2: Where there are differences between this AD and the 
referenced service bulletins or the 767 Master Minimum Equipment 
List (MMEL), the AD prevails.

Repetitive Inspections and Tests of Thrust Reverser Control System

    (a) Within 1,000 flight hours after the effective date of this 
AD, do a general visual inspection to detect discrepancies (i.e., 
wear, tears, cracks, missing segments, and improper folds, as 
applicable) and assess damage of the certain fail-safe features of 
the thrust reverser control system, and test for electrical 
continuity and resistance of those fail-safe features; per Section 
3., ``Accomplishment Instructions,'' of Boeing Alert Service 
Bulletin 767-78A0090, Revision 1, dated July 5, 2001 (for Model 767-
200, -300, and ``300F series airplanes), or Boeing Alert Service 
Bulletin 767-78A0091, Revision 1, dated July 5, 2001 (for Model 767-
400ER series airplanes); as applicable. Repeat the inspection and 
tests thereafter every 1,000 flight hours.

    Note 3: For the purposes of this AD, a general visual inspection 
is defined as ``A visual examination of an interior or exterior 
area, installation, or assembly to detect obvious damage, failure, 
or irregularity. This level of inspection is made under normally 
available lighting conditions such as daylight, hangar lighting, 
flashlight, or drop-light, and may require removal or opening of 
access panels or doors. Stands, ladders, or platforms may be 
required to gain proximity to the area being checked.''

Corrective Actions, If Necessary

    (b) Except as provided by paragraph (c) of this AD, do the 
applicable corrective actions specified in paragraph (b)(1), (b)(2), 
(b)(3), and (b)(4) of this AD per Boeing Alert Service Bulletin 767-
78A0090, Revision 1, dated July 5, 2001 (for Model 767-200, -300, 
and ``300F series airplanes), or Boeing Alert Service Bulletin 767-
78A0091, Revision 1, dated July 5, 2001 (for Model 767-400ER series 
airplanes); as applicable; at the time indicated in those 
paragraphs.
    (1) If any discrepancy is detected as indicated in Figure 1 of 
the applicable service bulletin, replace the bullnose seal with a 
new bullnose seal, per Figure 1 of the applicable service bulletin, 
at the applicable time indicated in paragraph (b)(1)(i) or 
(b)(1)(ii) of this AD.
    (i) For assessed cumulative damage between one and ten inches: 
Replace within 650 flight hours after the inspection.
    (ii) For assessed cumulative damage ten inches or more: Replace 
before further flight.
    (2) If the electrical continuity on the position switch module 
of the center drive unit (CDU) of the thrust reverser is found to be 
outside the limits (greater than 0.50 ohms) during any applicable 
test required by paragraph (a) of this AD, before further flight, do 
the corrective actions (i.e., replace discrepant position switch 
module with a new module, or replace the CDU with a new CDU), per 
Part 2 of Section 3., ``Accomplishment Instructions,'' of the 
applicable service bulletin.
    (3) If the resistance between pins 1 and 2 of either connector 
in the thrust reverser actuation system (TRAS) lock for ``hot 
short'' protection is greater than 4.0 ohms, before further flight, 
do the corrective actions (i.e., additional testing, replacement of 
the relay, and troubleshoot the connecting wires; as applicable) per 
Part 3 of Section 3., ``Accomplishment Instructions,'' of the 
applicable service bulletin.
    (4) If the resistance between pins 1 and 2 of the connector in 
the directional pilot valve (DPV) for ``hot short'' protection is 
greater than 4.0 ohms, before further flight, do the corrective 
actions (i.e., additional testing, replacement of the microswitch 
pack, and troubleshoot the connecting wires; as applicable) per Part 
4 of Section 3., ``Accomplishment Instructions,'' of the applicable 
service bulletin.

Exception to Corrective Action(s)

    (c) For those conditions identified in paragraph (b)(1) of this 
AD: The thrust reverser may be deactivated per the Master Minimum 
Equipment List (MMEL) for up to 10 days provided that, before 
further flight, the deactivation is done per Section 2-78-31-1 of 
Boeing Document D630T002, ``Boeing 767 Dispatch Deviation Guide,'' 
Revision 20, dated August 18, 2000. Within 10 days following 
accomplishment of the deactivation, do the applicable corrective 
action(s) specified in paragraph (b)(1), (b)(2), or (b)(4) of this 
AD. Before further flight following accomplishment of the applicable 
corrective action(s), reactivate the thrust reverser. No more than 
one thrust reverser on any airplane may be deactivated under the 
provisions of this paragraph.

Engine Replacement

    (d) Prior to installation of a General Electric Model CF6-80C2 
engine on any airplane, do the actions specified in paragraphs 
(d)(1) and (d)(2) of this AD, per Boeing Alert Service Bulletin 767-
78A0081, Revision 2, dated April 19, 2001 (for Model 767-200, -300, 
and ``300F series airplanes), or Boeing Alert Service Bulletin 767-
78A0088, dated April 19, 2001 (for Model 767-400ER series 
airplanes), as applicable.
    (1) Do a functional test on both thrust reversers for the 
electro-mechanical brakes (i.e., TRAS locks) and CDU cone brakes of 
both engines to verify proper holding torque per the Accomplishment 
Instructions of the applicable service bulletin. If any improper 
holding torque is detected, before further flight, accomplish 
corrective actions (e.g., ensure proper torque, replacement or 
installation of components, and additional inspections), as 
applicable, per the Accomplishment Instructions of the applicable 
service bulletin.
    (2) Do a test for electrical continuity of the position switch 
module of the CDU of the thrust reverser, per Part 2 of Section 3., 
``Accomplishment Instructions,'' of the applicable service bulletin, 
and before further flight, do corrective actions, if necessary, as 
specified in paragraph (b)(2) of this AD.

Alternative Methods of Compliance

    (e) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Seattle Aircraft Certification 
Office (ACO), FAA. Operators shall submit their requests through an 
appropriate FAA Principal Maintenance Inspector, who may add 
comments and then send it to the Manager, Seattle ACO.

    Note 4: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

Special Flight Permits

    (f) Special flight permits may be issued in accordance with 
Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 
21.197 and 21.199) to operate the airplane to a location where the 
requirements of this AD can be accomplished.

Incorporation by Reference

    (g) Except as provided by paragraph (c) of this AD, the actions 
shall be done in accordance with Boeing Alert Service Bulletin 767-
78A0090, Revision 1, dated July 5, 2001; Boeing Alert Service 
Bulletin 767-78A0091, Revision 1, dated July 5, 2001; Boeing Alert 
Service Bulletin 767-78A0081, Revision 2, dated April 19, 2001; and 
Boeing Alert Service Bulletin 767-78A0088, dated April 19, 2001; as 
applicable. This incorporation by reference was approved by the 
Director of the Federal Register in accordance with 5 U.S.C. 552(a) 
and 1 CFR part 51. Copies may be obtained from Boeing Commercial 
Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. 
Copies may be inspected at the FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington; or at the Office of the 
Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.

Effective Date

    (h) This amendment becomes effective on August 21, 2001.

    Issued in Renton, Washington, on July 27, 2001.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-19385 Filed 8-3-01; 8:45 am]
BILLING CODE 4910-13-U