[Federal Register Volume 63, Number 227 (Wednesday, November 25, 1998)]
[Rules and Regulations]
[Pages 65054-65055]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-31324]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-NM-13-AD; Amendment 39-10913; AD 98-24-26]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 747-400 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 747-400 series airplanes, that
requires replacing the cam assembly, cam bellcrank assembly, and thrust
reverser control switch actuator on all four thrust levers with new
components. This amendment is prompted by a report of an uncommanded
automatic retraction of the leading edge flaps during takeoff. The
actions specified by this AD are intended to prevent such uncommanded
automatic retraction, which would seriously degrade liftoff and climb
capabilities, and could result in near-stall conditions at a critical
phase of the flight.
DATES: Effective December 30, 1998.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of December 30, 1998.
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: Frank van Leynseele, Aerospace
Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft
Certification Office, 1601 Lind Avenue, SW., Renton, Washington;
telephone (206) 227-2671; fax (206) 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 747-400
series airplanes was published in the Federal Register on April 14,
1997 (62 FR 18063). That action proposed to require replacing the cam
assembly, cam bellcrank assembly, and thrust reverser control switch
actuator on all four thrust levers with new components.
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the comments received.
Request To Cite the Latest Service Information
Three commenters request that the proposed rule be revised to
reflect the latest revision of Boeing Alert Service Bulletin 747-
27A2356; the original issue of that service bulletin was referenced in
the proposal as the appropriate source of service information.
The FAA concurs with the commenters' request to reference the
latest revision of the service bulletin. The FAA has reviewed and
approved Boeing Service Bulletin 747-27A2356, Revision 1, dated August
13, 1998. That
[[Page 65055]]
revision of the service bulletin provides a correction to certain part
numbers of the cam bellcrank assemblies and clarifies certain part-
marking instructions. In addition, Revision 1 of the service bulletin
describes a revision of the operating position of the reverse thrust
isolation valve switches in the thrust levers. The FAA has revised the
final rule to reference Boeing Service Bulletin 747-27A2356, Revision
1, dated August 13, 1998, as the appropriate source of service
information. The FAA has determined that requiring the replacements to
be performed in accordance with Revision 1 of the service bulletin will
not pose an additional burden on any operator.
Request To Revise the Cost Impact Information
One commenter, the manufacturer, requests that the cost impact
information be corrected to reflect that 46 airplanes of U.S. registry
will be affected by this AD, rather than the 35 airplanes estimated in
the proposal. The FAA concurs and has revised the cost impact
information accordingly.
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 described
previously. 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 394 Boeing Model 747-400 series airplanes
of the affected design in the worldwide fleet. The FAA estimates that
46 airplanes of U.S. registry will be affected by this AD, that it will
take approximately 8 work hours per airplane to accomplish the required
actions, and that the average labor rate is $60 per work hour. Required
parts would cost between $3,412 and $4,740 per airplane. Based on these
figures, the cost impact of the AD is estimated to be between $179,032
and $240,120, or between $3,892 and $5,220 per airplane.
The cost impact figures discussed above are 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.
Regulatory Impact
The regulations adopted herein will not have substantial direct
effects 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, in
accordance with Executive Order 12612, it is determined that this final
rule does not have sufficient federalism implications to warrant the
preparation of a Federalism Assessment.
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:
98-24-26 Boeing: Amendment 39-10913. Docket 97-NM-13-AD.
Applicability: Model 747-400 series airplanes, line positions
696 through 1090 inclusive; 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 (b) 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 uncommanded automatic retraction of the leading edge
flaps during takeoff, which would seriously degrade liftoff and
climb capabilities, and could result in near-stall conditions,
accomplish the following:
(a) Within 18 months after the effective date of this AD,
accomplish the requirements of paragraph (a)(1) or (a)(2) of this
AD, as applicable, in accordance with Boeing Service Bulletin 747-
27A2356, Revision 1, dated August 13, 1998.
(1) For Groups 1 and 2 airplanes, as listed in the service
bulletin: Replace the cam assembly, cam bellcrank assembly, and
thrust reverser control switch actuator on all four thrust levers
with new components.
(2) For Groups 3 and 4 airplanes, as listed in the service
bulletin: Replace the cam bellcrank assembly and thrust reverser
control switch actuator on all four thrust levers with new
components.
(b) 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 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Seattle ACO.
(c) 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.
(d) The actions shall be done in accordance with Boeing Service
Bulletin 747-27A2356, Revision 1, dated August 13, 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.
(e) This amendment becomes effective on December 30, 1998.
Issued in Renton, Washington on November 18, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 98-31324 Filed 11-24-98; 8:45 am]
BILLING CODE 4910-13-U
