AD 2000-14-11

[Federal Register Volume 65, Number 139 (Wednesday, July 19, 2000)]
[Rules and Regulations]
[Pages 44663-44667]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 00-18037]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-64-AD; Amendment 39-11821; AD 2000-14-11]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747 Series Airplanes

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 747 series airplanes equipped with 
General Electric Model CF6-45 or -50 series engines, that requires 
repetitive inspections and tests of the thrust reverser control and 
indication system, and corrective actions, if necessary. This amendment 
also requires installation of a thrust reverser actuation system (TRAS) 
lock, repetitive functional tests of that installation, and repair, if 
necessary. Installation of the TRAS lock terminates the repetitive 
inspections and certain tests. This amendment is prompted by the 
results of a safety review, which revealed that in-flight deployment of 
a thrust reverser could result in a significant reduction in airplane 
controllability. The actions specified by this AD are intended to 
ensure the integrity of the fail-safe features of the thrust reverser 
system by preventing possible failure modes, which could result in 
inadvertent deployment of a thrust reverser during flight, and 
consequent reduced controllability of the airplane.

DATES: Effective August 23, 2000.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of August 23, 2000.

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: Larry Reising, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Transport Airplane Directorate, 
Seattle Aircraft Certification Office, 1601 Lind

[[Page 44664]]

Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2683; 
fax (425) 227-1181.

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 747 series 
airplanes equipped with General Electric Model CF6-45 or -50 series 
engines was published in the Federal Register on October 27, 1999 (64 
FR 57802). That action proposed to require repetitive inspections and 
tests of the thrust reverser control and indication system, and 
corrective actions, if necessary. That action also proposed to require 
installation of a thrust reverser actuation system (TRAS) lock, 
repetitive functional tests of that installation, and repair, if 
necessary. Installation of the TRAS lock would terminate the repetitive 
inspections and certain tests.

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 Rule

    One commenter supports the proposed rule.

Request To Revise Repetitive Interval in Paragraph (a)

    One commenter requests that the interval for the repetitive 
inspections and tests required by paragraph (a) of the proposed rule be 
extended from 1,300 flight hours to 1,500 flight hours. The commenter 
states that Work Package I of Boeing Alert Service Bulletin 747-
78A2160, dated May 4, 1995 [the service information referenced in 
paragraph (a) for accomplishment of the inspections and tests] has a 
repetitive interval of 1,500 flight hours, as specified in the service 
bulletin. The commenter adds that a 1,400-flight-hour-interval aligns 
with its ``2A'' check for the fleet, but the 1,300-flight-hour-interval 
will require additional downtime and place an undue burden on 
maintenance personnel. The commenter suggests, as another option, that 
the interval be changed to, ``1,500 flight hours or 450 flight cycles, 
whichever occurs later.'' Another commenter requests that the interval 
be changed to ``1,300 flight hours or 450 flight cycles, whichever 
occurs later.'' Both commenters state that the deterioration of the 
entire system is based on flight cycles, rather than flight hours.
    The FAA partially concurs. The FAA does not concur with the 
commenters' requests to revise the repetitive inspection interval to 
add the option of flight cycles. The FAA agrees that deterioration of 
certain thrust reverser components is related to flight cycles because 
the thrust reversers are typically operated once per flight, causing 
wear of the components of the actuation system and the thrust reverser 
brake. However, deterioration of the majority of thrust reverser 
components is related to flight hours. For example, deterioration of 
wiring, seals, and proximity sensors and switches is more commonly due 
to damage due to vibration, temperature extremes, and exposure to 
moisture. Such factors are flight-hour dependent. Based on this flight 
hour dependency, the FAA has determined that the inspection interval 
will not be revised to add the option of flight cycles.
    However, the FAA concurs with the commenters' request to extend the 
repetitive interval stated in the final rule to 1,500 flight hours. 
Based on discussions with the manufacturer, the FAA has determined that 
an extension of the interval for the repetitive inspections and tests 
required by paragraph (a) of the final rule will not have an adverse 
affect on fleet safety. Therefore, paragraph (a) of the final rule has 
been revised accordingly.

Request To Extend Compliance Time in Paragraph (d)

    One commenter requests that the compliance time for accomplishment 
of the modification required by paragraph (d) of the proposed rule be 
extended from 36 months to 60 months in order to allow the modification 
to be accomplished during the time of its regularly scheduled ``D'' 
check. The commenter states that the major portion of the modification 
involves installation of wiring provisions, and this installation 
requires a downtime of 250 hours. Another commenter requests the 
compliance time be extended to 84 months in order to allow the 
modification to be accomplished during the time of its regularly 
scheduled ``D'' check. The commenter states that the proposed 
requirement to accomplish the complete modification within 36 months, 
including all service bulletins, would create added problems instead of 
solutions. The commenter notes that the complete modification would 
require approximately 1,850 man hours to accomplish, and requests the 
extension to 84 months so airplanes will not be removed from service.
    The FAA partially concurs with the commenters' requests. The FAA 
concurs that the compliance time for accomplishment of the modification 
required by paragraph (d) of the final rule may be extended beyond 36 
months. Based on information supplied by the commenters and the 
manufacturer, the FAA acknowledges that a compliance time of 48 months 
corresponds more closely to the operators' normal maintenance 
schedules. The FAA has determined that this extension will not 
adversely affect safety. However, the FAA has concluded that a 
compliance time of 48 months represents the maximum interval in which 
the affected airplanes could continue to operate without compromising 
safety. Paragraph (d) of the final rule has been revised to require 
accomplishment of the modification within 48 months after the effective 
date of this AD.

Request To Remove Mandatory Terminating Action in Paragraph (d)

    One commenter disagrees with the mandatory requirement to 
incorporate a TRAS lock as specified in paragraph (d) of the proposed 
rule. The commenter states that an equivalent level of safety is 
achieved by accomplishing the thrust reverser health checks at the 
intervals specified in Boeing Alert Service Bulletin 747-78A2160, dated 
May 4, 1995, including Notice of Status Change 747-78A2160 NSC 1, dated 
June 8, 1995. The commenter cites fleet statistics that Model 747 
series airplanes have flown over 47,212,499 hours to date without any 
corresponding thrust reverser deployments that have impacted the safety 
of flight. The commenter further states that the events which triggered 
regulatory action happened due to thrust reverser deployment of a Model 
767 series airplane having two engines and subsequent controllability 
problems. The commenter also states that there is insufficient 
documentation from the manufacturer for troubleshooting and correcting 
operational problems with the TRAS lock. Additionally, there were no 
adverse operational trends indicated that would impact safety of flight 
of the Model 747 series airplane; therefore, incorporation of the 
additional TRAS lock is not justified.
    The FAA does not concur with the commenter's request. The FAA 
recognizes that in-flight thrust reverser deployments have occurred on 
Model 747 series airplanes in certain flight conditions with no 
significant airplane controllability problems being reported. However, 
the manufacturer has been unable to establish that acceptable airplane 
controllability would be achieved following such a deployment.

[[Page 44665]]

The manufacturer acknowledges that, in the event of thrust reverser 
deployment during high-speed climb using high engine power, or during 
cruise, these airplanes may not be controllable.
    Although the commenter states that there were no adverse 
operational trends that would impact safety of flight, the safety 
analyses performed by the manufacturer and reviewed by the FAA has not 
established that the risks for uncommanded thrust reverser deployment 
during critical flight conditions are low enough to prevent a thrust-
reverser-related incident during the fleet operation of the Model 747 
series airplane. This AD addresses an unsafe condition identified as 
deployment of a thrust reverser during flight, and requires the 
installation of an additional thrust reverser system locking feature to 
correct that unsafe condition. The periodic inspections and tests 
(thrust reverser health checks) contained in paragraphs (a) and (b) of 
this AD are a means of verifying proper operation of the thrust 
reverser components. The FAA has determined that the terminating action 
required by paragraph (d) of this AD is necessary because the 
repetitive inspections and tests do not provide an adequate level of 
safety for the remainder of the life of the fleet of Model 747 series 
airplanes. Regarding the insufficiency of documentation from the 
manufacturer, the FAA has been advised by the manufacturer that 
additional documentation is being developed. No change to the final 
rule is necessary in this regard.

Comment on Repetitive Inspection Interval in Paragraph (e)

    One commenter does not fully agree with the repetitive inspection 
interval required by paragraph (e) of the proposed rule, ``since 
limited data is available.'' The commenter makes no specific request 
for a change to the proposed rule.
    The FAA infers that the commenter is requesting an extension of the 
repetitive inspection interval for the functional test required by 
paragraph (e) of the final rule. The FAA does not concur with the 
commenter's request. In developing an appropriate repetitive interval 
for this action, the FAA considered not only the degree of urgency 
associated with addressing the subject unsafe condition, but 
accomplishment of the required repetitive functional test within an 
interval of time that parallels normal scheduled maintenance for the 
majority of affected operators. However, under the provisions of 
paragraph (h) of the final rule, the FAA may approve requests for 
adjustments to the compliance time if data are submitted to 
substantiate that such an adjustment would provide an acceptable level 
of safety. No change to the final rule is necessary in this regard.

Request To Revise Cost Impact Estimate

    One commenter asserts that the proposed rule underestimates the 
work hours required to accomplish the proposed installation of the TRAS 
lock. The commenter states that, based upon feedback from operators 
that have installed the TRAS lock, approximately 1,850 work hours per 
airplane is needed for accomplishment of the installation; these hours 
include all pre-requisite service bulletins. The commenter also notes 
that it uses third party labor and does not agree that $60 per work 
hour is the industry average labor rate. The commenter estimates that 
$100 per work hour is more realistic. Using these figures, the 
commenter estimates its costs for the proposed installation as $185,000 
per airplane, or $4,070,000 for its entire fleet. The commenter adds 
that it would take an additional 40 work hours per airplane to 
accomplish the proposed repetitive inspections and tests of the 
overpressure shutoff valve electrical connectors, the flexible shafts, 
the directional pilot valves, and the microswitch packs, which equates 
to $4,000 per airplane. The proposed rule estimates 11 work hours for 
accomplishment of these repetitive inspections and tests.
    The FAA infers that the commenter is requesting that the cost 
impact information in the final rule be revised to reflect the estimate 
derived from operator feedback. The FAA does not concur with the 
commenter's request. The cost impact information in AD rulemaking 
actions describes only the ``direct'' costs of the specific actions 
required by this AD. The number of work hours necessary to accomplish 
the required actions was provided to the FAA by the manufacturer based 
on the best data available to date. This number represents the time 
necessary to perform only the actions actually required by this AD. The 
FAA recognizes that, in accomplishing the requirements of any AD, 
operators may incur ``incidental'' costs in addition to the ``direct'' 
costs. The cost analysis in AD rulemaking actions, however, typically 
does not include incidental costs, such as the time required to gain 
access and close up, planning time, or time necessitated by other 
administrative actions. Because incidental costs may vary significantly 
from operator to operator, they are almost impossible to calculate. 
Therefore, no change to the final rule is necessary.

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 138 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 27 airplanes of U.S. registry 
will be affected by this AD.
    It will take approximately 12 work hours per airplane to accomplish 
the inspections and tests of the thrust reverser stow/deploy switches, 
the bullnose seals, and the airmotor brakes, at an average labor rate 
of $60 per work hour. Based on these figures, the cost impact of these 
repetitive inspections and tests required by this AD on U.S. operators 
is estimated to be $19,440, or $720 per airplane, per inspection and 
test cycle.
    It will take approximately 11 work hours per airplane to accomplish 
the inspections and tests of the overpressure shutoff valve electrical 
connectors, the flexible shafts, the directional pilot valves, and the 
microswitch packs, at an average labor rate of $60 per work hour. Based 
on these figures, the cost impact of these repetitive inspections and 
tests required by this AD on U.S. operators is estimated to be $17,820, 
or $660 per airplane, per inspection and test cycle.
    It will take approximately 791 work hours per airplane to 
accomplish the installation of TRAS locks, at an average labor rate of 
$60 per work hour. Required parts will be provided at no cost by the 
airplane manufacturer. Based on these figures, the cost impact of the 
installation required by this AD on U.S. operators is estimated to be 
$1,281,420, or $47,460 per airplane.
    This cost impact figure does not reflect the cost of the 
modifications described in the service bulletins listed in paragraph 
I.K.1.h. of Boeing Service Bulletin 747-78-2150, Revision 1, that are 
required to be accomplished prior to, or concurrently with, the 
installation of the TRAS lock. (The cost impact figure does reflect the 
cost of the modifications described in the service bulletins listed in 
paragraph I.K.1.j. of the service bulletin that are also required to be 
accomplished prior to, or concurrently with, the installation of the

[[Page 44666]]

TRAS lock.) Since some operators may have accomplished certain 
modifications on some or all of the airplanes in its fleet, while other 
operators may not have accomplished any of the modifications on any of 
the airplanes in its fleet, the FAA is unable to provide a reasonable 
estimate of the cost of accomplishing the terminating actions described 
in the service bulletins listed in paragraph I.K.1.h. of Boeing Service 
Bulletin 747-78-2150.
    It will take approximately 4 work hours per airplane to accomplish 
the functional test of the TRAS lock, at an average labor rate of $60 
per work hour. Based on these figures, the cost impact of the 
repetitive functional tests required by this AD on U.S. operators is 
estimated to be $6,480, or $240 per airplane, per test cycle.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the proposed requirements 
of this AD action, and that no operator would accomplish those actions 
in the future if this AD were not adopted.

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:

2000-14-11  Boeing: Amendment 39-11821. Docket 99-NM-64-AD.

    Applicability: Model 747 series airplanes; certificated in any 
category; equipped with General Electric Model CF6-45 or -50 series 
engines.

    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 (h) 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 the integrity of the fail-safe features of the thrust 
reverser system by preventing possible failure modes, which could 
result in inadvertent deployment of a thrust reverser during flight, 
and consequent reduced controllability of the airplane, accomplish 
the following:

Repetitive Inspections and Tests

    Note 2: For the purposes of this AD, a detailed visual 
inspection is defined as: ``An intensive visual examination of a 
specific structural area, system, installation, or assembly to 
detect damage, failure, or irregularity. Available lighting is 
normally supplemented with a direct source of good lighting at 
intensity deemed appropriate by the inspector. Inspection aids such 
as mirror, magnifying lenses, etc., may be used. Surface cleaning 
and elaborate access procedures may be required.''

    (a) Within 90 days after the effective date of this AD, perform 
the applicable detailed visual inspections and tests to verify 
proper operation of the thrust reverser stow/deploy switches, the 
bullnose seals, and the airmotor brake on each engine, in accordance 
with Work Package I of the Accomplishment Instructions of Boeing 
Alert Service Bulletin 747-78A2160, dated May 4, 1995, including 
Notice of Status Change 747-78A2160 NSC 1, dated June 8, 1995. 
Repeat the applicable inspections and tests thereafter at intervals 
not to exceed 1,500 flight hours, until accomplishment of paragraph 
(d) of this AD.
    (b) Within 6 months after the effective date of this AD, perform 
the applicable detailed visual inspections and tests to verify 
proper operation of the overpressure shutoff valve electrical 
connectors, the flexible shafts, the directional pilot valve, and 
the microswitch pack for each engine, in accordance with Work 
Package II of the Accomplishment Instructions of Boeing Alert 
Service Bulletin 747-78A2160, dated May 4, 1995, including Notice of 
Status Change 747-78A2160 NSC 1, dated June 8, 1995. Repeat the 
applicable inspections and tests thereafter at intervals not to 
exceed 18 months, until accomplishment of paragraph (d) of this AD.

Corrective Actions

    (c) If any of the inspections and tests required by paragraphs 
(a) and (b) of this AD cannot be successfully performed, or if any 
discrepancy is detected during the inspections and tests, accomplish 
paragraphs (c)(1) or (c)(2) of this AD, as applicable.
    (1) Prior to further flight, repair in accordance with Boeing 
Alert Service Bulletin 747-78A2160, dated May 4, 1995. Additionally, 
prior to further flight, any failed inspection or test required by 
paragraph (a) or (b) of this AD must be repeated and successfully 
accomplished.
    (2) Accomplish both paragraphs (c)(2)(i) and (c)(2)(ii) of this 
AD.
    (i) Prior to further flight, deactivate the associated thrust 
reverser in accordance with Section 78-1 of Boeing Document D6-
33391, ``Boeing 747-100/-200/-300/SPDispatch Deviations Procedures 
Guide,'' Revision 22, dated January 30, 1998. No more than one 
thrust reverser on any airplane may be deactivated under the 
provisions of this paragraph.

    Note 3: The airplane may be operated in accordance with the 
provisions and limitations specified in the operator's FAA-approved 
Minimum Equipment List (MEL), provided that no more than one thrust 
reverser on the airplane is inoperative.

    (ii) Within 10 days after deactivation of any thrust reverser in 
accordance with paragraph (c)(2)(i) of this AD, the affected thrust 
reverser must be repaired in accordance with Boeing Alert Service 
Bulletin 747-78A2160, dated May 4, 1995. Additionally, prior to 
further flight, any failed inspection or test required by paragraph 
(a) or (b) of this AD must be repeated and successfully 
accomplished; once such inspections and tests have been successfully 
accomplished, the thrust reverser may then be reactivated.

Modification

    (d) Within 48 months after the effective date of this AD, 
install a thrust reverser actuation system (TRAS) lock on each 
thrust reverser half of each engine, in accordance with Boeing 
Service Bulletin 747-78-2150, Revision 1, dated July 2, 1998. All of 
the modifications described in the service bulletins listed in 
paragraphs I.K.1.h. and I.K.1.j. of Boeing Service Bulletin 747-78-
2150, Revision 1, must be accomplished, as applicable, in accordance 
with those service bulletins, prior to, or concurrently with, the 
accomplishment of the installation of the TRAS lock. Accomplishment 
of these actions constitutes terminating action for the

[[Page 44667]]

repetitive inspections required by paragraphs (a) and (b) of this 
AD.

    Note 4: Accomplishment of the installation specified in Boeing 
Service Bulletin 747-78-2150, dated March 20, 1997, is acceptable 
for compliance with the installation required by paragraph (d) of 
this AD.

Functional Tests

    (e) Within 3,000 flight hours after accomplishing the 
modification required by paragraph (d) of this AD, or within 1,000 
flight hours after the effective date of this AD, whichever occurs 
later, perform a functional test of the TRAS lock on each reverser 
half, in accordance with Chapter 78-34-00 of the Boeing 747 
Maintenance Manual, dated April 25, 1998.

Corrective Actions

    (1) If no discrepancy is detected, repeat the functional test 
thereafter at intervals not to exceed 3,000 flight hours.
    (2) If any discrepancy is detected, prior to further flight, 
repair in accordance with the procedures specified in the Boeing 747 
Maintenance Manual. Additionally, prior to further flight, the 
functional test must be successfully accomplished. Repeat the 
functional test thereafter at intervals not to exceed 3,000 flight 
hours.

Spares

    (f) If, after incorporation of the modification required by 
paragraph (d) of this AD on any airplane, it becomes necessary to 
install a thrust reverser assembly that does not have the TRAS locks 
installed, dispatch of the airplane is allowed in accordance with 
the provisions and limitations specified in the operator's FAA-
approved MEL, provided that the thrust reverser assembly that does 
not have the TRAS locks installed is deactivated in accordance with 
Section 78-1 of Boeing Document D6-33391, ``Boeing 747-100/-200/-
300/SP Dispatch Deviations Procedures Guide,'' Revision 22, dated 
January 30, 1998. No more than one thrust reverser on any airplane 
may be deactivated under the provisions of this paragraph. Within 10 
days after deactivation of the thrust reverser, install a thrust 
reverser assembly that has the TRAS locks installed and reactivate 
the thrust reverser.
    (g) If, prior to incorporation of the modification required by 
paragraph (d) of this AD on any airplane, it becomes necessary to 
install a thrust reverser assembly that has the TRAS locks 
installed, dispatch of the airplane is allowed in accordance with 
the provisions and limitations specified in the operator's FAA-
approved MEL, provided that the thrust reverser assembly that has 
the TRAS locks installed is deactivated in accordance with Section 
78-1 of Boeing Document D6-33391, ``Boeing 747-100/-200/-300/SP 
Dispatch Deviations Procedures Guide,'' Revision 22, dated January 
30, 1998. No more than one thrust reverser on any airplane may be 
deactivated under the provisions of this paragraph. Within 10 days 
after deactivation of the thrust reverser, install a thrust reverser 
assembly that does not have the TRAS locks installed and reactivate 
the thrust reverser.

Alternative Methods of Compliance

    (h) 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, Transport Airplane Directorate. 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 5: 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

    (i) Special flight permits may be issued in accordance with 
sections 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

    (j) Except as provided by paragraphs (c)(2)(i), (e), (e)(2), 
(f), and (g) of this AD, the actions shall be done in accordance 
with Boeing Alert Service Bulletin 747-78A2160, dated May 4, 1995, 
including Notice of Status Change 747-78A2160 NSC 1, dated June 8, 
1995; and Boeing Service Bulletin 747-78-2150, Revision 1, dated 
July 2, 1998. 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.
    (k) This amendment becomes effective on August 23, 2000.

    Issued in Renton, Washington, on July 11, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-18037 Filed 7-18-00; 8:45 am]
BILLING CODE 4910-13-P