AD 2002-19-11

[Federal Register Volume 67, Number 190 (Tuesday, October 1, 2002)]
[Rules and Regulations]
[Pages 61478-61481]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 02-24405]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-268-AD; Amendment 39-12891; AD 2002-19-11]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 767-200 and -300 Series 
Airplanes Powered by Pratt & Whitney JT9D Series Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Boeing Model 767-200 and -300 series airplanes 
powered by Pratt & Whitney JT9D series engines, that requires 
replacement of the existing deactivation pin, aft cascade pin bushing, 
and pin insert on each thrust reverser half, with new, improved 
components. This action is necessary to prevent failure of the thrust 
reverser deactivation pins, which could result in deployment of the 
thrust reverser in flight and consequent reduced controllability of the 
airplane. This action is intended to address the identified unsafe 
condition.

DATES: Effective November 5, 2002.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of November 5, 2002.

ADDRESSES: 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 Federal 
Aviation Administration (FAA), Transport Airplane Directorate, Rules 
Docket, 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: Technical Information: John Vann, 
Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-
4056; telephone (425) 227-1024; fax (425) 227-1181.
    Other Information: Judy Golder, Airworthiness Directive Technical 
Editor/Writer; telephone (425) 687-4241, fax (425) 227-1232. Questions 
or comments may also be sent via the Internet using the following 
address: <a href="/cdn-cgi/l/email-protection#254f50415c0b424a49414057654344440b424a53"><span class="__cf_email__" data-cfemail="d0baa5b4a9feb7bfbcb4b5a290b6b1b1feb7bfa6">[email&#160;protected]</span></a>. Questions or comments sent via the 
Internet as attached electronic files must be formatted in Microsoft 
Word 97 for Windows or ASCII text.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to certain Boeing Model 767-200 and -
300 series airplanes powered by Pratt & Whitney (P&W) JT9D series 
engines was published in the Federal Register on November 19, 2001 (66 
FR 57904). That action proposed to require replacement of the existing 
deactivation pin, aft cascade pin bushing, and pin insert on each 
thrust reverser half, with new, improved components.

[[Page 61479]]

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

Support for the Proposed AD

    One commenter supports the proposed AD, and notes that the design 
of the thrust reverser system on Model 767 series airplanes powered by 
P&W JT9D series engines is similar to that on Model 767 series 
airplanes equipped with P&W PW4000 series engines.

Disagreement With Proposed AD/Request for Withdrawal

    Two commenters disagree with the proposed AD, and one of these 
commenters requests that the FAA withdraw the proposal.
    Both commenters note that the proposed AD is prompted by partial 
deployment of the thrust reversers on airplanes equipped with P&W 
PW4000 series airplanes, and no similar incidents have occurred on 
airplanes equipped with P&W JT9D series engines. The commenters 
emphasize that there are significant differences in design and function 
between the thrust reverser systems on these two engine models. Both 
commenters point out that, while the thrust reverser system on Model 
767 P&W PW4000 series engines incorporates two hydraulic isolation 
valves--a motorized hydraulic isolation valve for deployment and a 
hydraulic stow valve for stowage, the thrust reverser system on Model 
767 P&W JT9D series engines has only a hydraulic isolation valve, and 
no motorized isolation valve. The commenters maintain that the 
differences between the thrust reverser systems on the two engine 
models make the identified unsafe condition unique to P&W PW4000 series 
engines.
    As further evidence of this, the commenters emphasize that the 
previous incidents occurred due to improper deactivation of the 
motorized isolation valve in the thrust reverser system by maintenance 
personnel who were not properly trained or did not follow procedures 
for proper deactivation of the thrust reverser system. Finally, both 
commenters point out that all previous incidents have occurred after 
landing during a commanded thrust reverser deployment, and they assert 
that this is not a safety-of-flight concern, but an economic concern 
(i.e., potential significant damage to the thrust reverser sleeves).
    We do not concur with the request to withdraw the proposed AD. 
Although we recognize that there are differences between the two thrust 
reverser systems, we find that the similarities between the two thrust 
reverser systems make airplanes powered by JT9D series engines 
potentially subject to the identified unsafe condition. We note that 
the airplane manufacturer also considers these similarities sufficient 
to create the risk of an in-flight deployment of a thrust reverser.
    Also, while we acknowledge that all previous incidents on Model 767 
series airplanes powered by P&W PW4000 series engines occurred after 
landing, the airplane manufacturer has reported an incident of a 
partial in-flight deployment on a Model 747-400 series airplane powered 
by P&W PW4000 series engines. That incident has been attributed to 
improper deactivation of the thrust reverser. When deactivated, the 
thrust reverser is restrained by locking the hydraulic valve, locking 
and deactivating the sync lock, and inserting the deactivation pin. 
However, maintenance crews occasionally will improperly deactivate the 
hydraulic valve or sync lock, leaving only the structural integrity of 
the deactivation pin as protection from in-flight deployment. 
Considering the criticality of a deployment of a thrust reverser in 
mid-flight, we consider this a safety-of-flight issue.
    Further, we acknowledge the commenters' remarks on training and 
supervision deficiencies. While increased training and proper 
supervision can alleviate the noted problems, current levels of 
training and supervision have not reduced the incidents of improper 
maintenance to an acceptable level.
    For the reasons stated previously, we find that no change to the 
final rule is necessary in this regard.

Acknowledge Errors in the Work Instructions in Service Bulletin

    The commenter that urges us to withdraw the proposed AD (as 
described in the previous section) states that the Work Instructions in 
Boeing Alert Service Bulletin 767-78A0089, dated July 19, 2001, cannot 
be accomplished on the thrust reverser system on Model 767 P&W JT9D 
series engines. The commenter points out that certain steps in the work 
instructions refer to components that do not exist on Model 767 P&W 
JT9D series engines. As noted previously, while the thrust reverser 
system on Model 767 P&W PW4000 series engines has two hydraulic 
isolation valves--a motorized hydraulic isolation valve for deployment 
and a hydraulic stow valve for stowage, the thrust reverser system on 
Model 767 P&W JT9D series engines has only a hydraulic isolation valve, 
no motorized isolation valve. Therefore, for example, the instruction 
in paragraph 3.B.4. of Boeing Alert Service Bulletin 767-78A0089 to 
``Deactivate the Motorized Isolation Valve and the Stow Valve * * *'' 
cannot be done because there are not two valves to deactivate on the 
thrust reverser system on Model 767 P&W JT9D series engines.
    These observations were part of the commenter's request for us to 
withdraw the proposed AD. We do not concur with this request. However, 
we acknowledge that the wording of the instructions in paragraphs 
3.B.4. and 3.L.1. of Boeing Alert Service Bulletin 767-78A0089 is 
somewhat confusing.
    Since we issued the notice of proposed rulemaking (NPRM), Boeing 
has issued Alert Service Bulletin 767-78A0089, Revision 1, dated May 
30, 2002. Among other changes, Revision 1 of the service bulletin 
corrects the errors in the work instructions of the original issue of 
the service bulletin to which the commenter refers. Therefore, for 
clarification, we find it appropriate to revise paragraph (a) of this 
final rule to refer to Revision 1 of the service bulletin as the 
appropriate source of service information for the actions required by 
that paragraph. Also, we have added a new paragraph (b) to this final 
rule to state that replacements accomplished before the effective date 
of this AD according to the original issue of the service bulletin are 
acceptable for compliance with this AD.

Allow Modification During In-Shop Maintenance

    One commenter requests that we revise the instructions of the 
referenced service bulletin to allow accomplishment of the replacement 
during maintenance, while the engine nacelle is off the wing, rather 
than with the engine nacelle mounted on the wing of the airplane. The 
commenter states that the service bulletin does not provide appropriate 
procedures for doing this. Specifically, the commenter requests that we 
revise the instructions in the service bulletin to provide for 
accomplishment of paragraphs 3.C. to 3.K. of the Work Instructions of 
the referenced service bulletin in the shop.
    We agree that the service bulletin instructions need to be revised. 
As stated previously, since the issuance of the NPRM, Boeing has issued 
Revision 1 of the service bulletin. In addition to the changes 
explained previously, Revision 1 of the service bulletin adds a new 
Work Package III, which provides the instructions for modification of a 
spare thrust reverser that the commenter

[[Page 61480]]

requests. We previously explained that we have revised paragraph (a) of 
this final rule to refer to Revision 1 of the service bulletin as the 
appropriate source of service information for the actions required by 
that paragraph, and we have added paragraph (b) to this final rule to 
give credit for replacements accomplished before the effective date of 
this AD according to the original issue of the service bulletin. 
Therefore, no further change to this final rule is necessary.

Limit Number of Tests

    The same commenter requests that we reduce the number of post-
replacement test cycles (extension and retraction of the thrust 
reverser to make sure it operates correctly), from three times, as 
specified in the service bulletin, to one time. The commenter states 
that, if the replacement is done with the engine nacelle in the shop 
rather than mounted on the wing, three test cycles are not necessary.
    We do not concur. The commenter provides no data to justify its 
request, and we see no advantage to reducing the number of test cycles 
from three to one. However, if an operator considers that such a 
reduction in the number of test cycles will provide an acceptable level 
of safety, the operator may request approval of an alternative method 
of compliance with this testing requirement, as provided by paragraph 
(c) of this AD. No change to the final rule is necessary in this 
regard.

Reduce Compliance Time

    One commenter is concerned that the compliance time of 24 months 
allowed by the proposed AD may be too long. The commenter states, 
however, that it assumes that the FAA has carried out an appropriate 
risk assessment to justify the proposed compliance time.
    We infer that the commenter is requesting that we reduce the 
proposed compliance time for the actions required by this AD. We do not 
concur. The commenter provides no data to justify its statement that 
the proposed compliance time may be too long. As stated in the proposed 
AD, in developing an appropriate compliance time for this AD, we 
considered not only the manufacturer's recommendation, but the degree 
of urgency associated with addressing the subject unsafe condition, the 
average utilization of the affected fleet, and the time necessary to 
perform the replacement. In light of these factors, we find that 24 
months is an appropriate interval to allow affected airplanes to 
continue to operate without compromising safety. No change to the final 
rule is necessary in this regard.

Extend Compliance Time

    One commenter requests that we extend the compliance time for the 
proposed requirements from 24 months to 30 months. The commenter states 
that it would like to do the proposed replacement during a scheduled 
maintenance visit, but sufficient parts may not be available to allow 
for this.
    We do not concur with the request to extend the compliance time for 
the actions required by this AD. Based on the latest information 
provided to us by the airplane manufacturer, an ample supply of 
required parts will be available within the 24-month compliance period. 
As stated previously, we find that 24 months is an appropriate interval 
for affected airplanes to continue to operate without compromising 
safety. No change to the final rule is necessary in this regard.

Explanation of Additional Change to Proposed AD

    For clarification, we have made minor revisions to the wording of 
Note 2 of this final rule.

Conclusion

    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes previously 
described. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.

Cost Impact

    There are approximately 90 Model 767-200 and -300 series airplanes 
of the affected design in the worldwide fleet. The FAA estimates that 
26 airplanes of U.S. registry will be affected by this AD, that it will 
take approximately 12 work hours (6 work hours per engine) per airplane 
to accomplish the required actions, and that the average labor rate is 
$60 per work hour. Required parts will cost approximately $12,108 per 
airplane. Based on these figures, the cost impact of this AD on U.S. 
operators is estimated to be $333,528, or $12,828 per airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the requirements of this AD 
action, and that no operator would accomplish those actions in the 
future if this AD were not adopted. The cost impact figures discussed 
in AD rulemaking actions represent only the time necessary to perform 
the specific actions actually required by the AD. These figures 
typically do not include incidental costs, such as the time required to 
gain access and close up, planning time, or time necessitated by other 
administrative actions.

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.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under 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. A final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it 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:

2002-19-11 Boeing: Amendment 39-12891. Docket 2001-NM-268-AD.

    Applicability: Model 767-200 and -300 series airplanes powered 
by Pratt & Whitney JT9D series engines, certificated in any 
category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability

[[Page 61481]]

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 (c) 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 prevent failure of the thrust reverser deactivation pins, 
which could result in deployment of the thrust reverser in flight 
and consequent reduced controllability of the airplane, accomplish 
the following:

Replacement

    (a) Within 24 months after the effective date of this AD, 
replace the existing deactivation pin, pin bushing in the aft 
cascade mounting ring, and pin insert on each thrust reverser half, 
with new, improved components, according to Boeing Alert Service 
Bulletin 767-78A0089, Revision 1, dated May 30, 2002.

    Note 2: The new, improved insert flange and pin bushing does not 
physically preclude use of a deactivation pin having P/N 315T1604-2 
or -5. However, use of deactivation pins having P/N 315T1604-2 or -5 
may not prevent the thrust reversers from deploying in the event of 
a full powered deployment. Therefore, thrust reversers modified per 
this AD are required to be installed with the new, longer 
deactivation pins having P/N 315T1604-6, as specified in the service 
bulletin.

Credit for Actions Accomplished According to Previous Service Bulletin 
Issue

    (b) Replacements accomplished before the effective date of this 
AD according to Boeing Alert Service Bulletin 767-78A0089, dated 
July 19, 2001, are acceptable for compliance with the corresponding 
action required by this AD.

Alternative Methods of Compliance

    (c) 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 3: 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

    (d) Special flight permits may be issued in accordance with 
Sec. Sec.  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

    (e) Unless otherwise specified in this AD, the actions shall be 
done in accordance with Boeing Alert Service Bulletin 767-78A0089, 
Revision 1, dated May 30, 2002. 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

    (f) This amendment becomes effective on November 5, 2002.

    Issued in Renton, Washington, on September 19, 2002.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 02-24405 Filed 9-30-02; 8:45 am]
BILLING CODE 4910-13-P