[Federal Register Volume 63, Number 182 (Monday, September 21, 1998)]
[Rules and Regulations]
[Pages 50130-50132]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-24902]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-NM-28-AD; Amendment 39-10769; AD 98-20-03]
RIN 2120-AA64
Airworthiness Directives; Fokker Model F.28 Mark 1000, 2000,
3000, and 4000 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 all Fokker Model F.28 Mark 1000, 2000, 3000, and 4000
series airplanes, that requires repetitive inspections of the center
joint of the main landing gear (MLG) torque link and the MLG assembly
for excessive free-play; and correction, if necessary. This AD also
requires installation of new MLG torque link dampers, which constitutes
terminating action for the repetitive inspections; and revision of the
FAA-approved maintenance program to incorporate inspections and
overhaul of the new torque link dampers. This amendment is prompted by
issuance of mandatory continuing airworthiness information by a foreign
civil airworthiness authority. The actions specified by this AD are
intended to prevent the failure of MLG torque links, which could result
in reduced controllability of the airplane on the ground during takeoff
or landing.
DATES: Effective October 26, 1998.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of October 26, 1998.
ADDRESSES: The service information referenced in this AD may be
obtained from Fokker Services B.V., Technical Support Department, P.O.
Box 75047, 1117 ZN Schiphol Airport, the Netherlands. 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: Norman B. Martenson, Manager,
International Branch, ANM-116, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425)
227-2110; fax (425) 227-1149.
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 all Fokker Model F.28 Mark 1000,
2000, 3000, and 4000 series airplanes was published in the Federal
Register on April 2, 1998 (63 FR 16177). That action proposed to
require repetitive inspections of the center joint of the main landing
gear (MLG) torque link and the MLG assembly for excessive free-play;
and correction, if necessary. That action also proposed to require
installation of new MLG torque link dampers, which would constitute
terminating action for the repetitive inspections; and revision of the
FAA-approved maintenance program to incorporate inspections and
overhaul of the new torque link dampers.
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 That Final Rule Not Be Issued
The single commenter, an operator, states that the requirements of
the proposed rule are unnecessary. The commenter states that the
incident that initiated the Dutch airworthiness directive was caused by
certain operators' failure to adequately maintain their landing gear,
wheels, brakes, and tires. The commenter further notes that
accomplishment of the proposed installation of a shimmy damper could
allow airlines to lengthen the time between replacement and repair of
those worn parts, which would exacerbate the
[[Page 50131]]
condition. The commenter concludes that the requirements of the
proposed rule would unfairly penalize operators who have adequately
maintained their airplanes and have no problems with vibration.
The FAA does not concur that the requirements of this AD are
unnecessary. As explained in the preamble of the proposed rule, the
Dutch airworthiness authority [Rijksluchtvaartdienst (RLD)] advised the
FAA that it received numerous reports of MLG torque link failure on in-
service airplanes. The cause of these failures has been attributed to
one or more deficiencies, such as excessive play in hinges and
bearings, worn or non-approved tires, or nitrogen or tire pressure that
is too high. Such deficiencies caused reduced natural stability of the
MLG in a lateral and torsional mode during landing, resulting in
vibration and consequent failure of the MLG torque links.
Although the deficiencies are maintenance-related, the FAA
considers that the large number of deficiencies reported is sufficient
evidence that an unsafe condition exists. Therefore, this AD action
addresses certain identified deficiencies that may result in an unsafe
condition (reduced controllability of the airplane on the ground during
takeoff or landing), and requires corrective action, if necessary.
Request for Approval of Alternative Method of Compliance
The commenter also requests approval of an alternative method of
compliance that consists of an enhanced maintenance program for landing
gear components. The commenter provided correspondence indicating that
Transport Canada Aviation (the airworthiness authority for Canada) has
approved the commenter's request for an alternative method of
compliance based on the enhanced maintenance program.
The FAA does not concur that this final rule should be revised to
reflect approval of an alternative method of compliance. The
information submitted by the commenter is insufficient for the FAA to
evaluate the commenter's suggestion. However, under the provisions of
paragraph (d) of this final rule, the FAA may consider requests for
approval of an alternative method of compliance if sufficient data are
submitted to substantiate that such a design change would provide an
acceptable level of safety.
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 as proposed.
Cost Impact
The FAA estimates that 27 airplanes of U.S. registry will be
affected by this AD. It will take approximately 3 work hours per
airplane to accomplish the required inspections, at an average labor
rate of $60 per work hour. Based on these figures, the cost impact of
the inspections required by this AD on U.S. operators is estimated to
be $4,860, or $180 per airplane, per inspection cycle.
It will take approximately 18 work hours per airplane to accomplish
the required installation/modification, at an average labor rate of $60
per work hour. Required parts will cost approximately $90,000 per
airplane. Based on these figures, the cost impact of the installation/
modification required by this AD on U.S. operators is estimated to be
$2,459,160, or $91,080 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:
98-20-03 Fokker Services B.V.: Amendment 39-10769. Docket 98-NM-28-
AD.
Applicability: All Model F.28 Mark 1000, 2000, 3000, and 4000
series airplanes, 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 (d) 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 the failure of main landing gear (MLG) torque links,
which could result in reduced controllability of the airplane on the
ground during takeoff or landing, accomplish the following:
(a) Within 1,000 flight cycles after the effective date of this
AD, perform a visual inspection of the center joint of the MLG
torque link for excessive free play, in accordance with Part 1.D. of
the Accomplishment Instructions of Fokker Service Bulletin F28/32-
151, Revision 1, dated March 12, 1997.
(1) If no discrepancy is detected, repeat the visual inspection
thereafter at intervals not to exceed 1,000 flight cycles.
(2) If any discrepancy is detected, prior to further flight,
correct the discrepant condition in accordance with Part 1.D. of the
Accomplishment Instructions of the service bulletin. Repeat the
visual inspection thereafter at intervals not to exceed 1,000 flight
cycles.
Note 2: Part 1.D. of the Accomplishment Instructions of Fokker
Service Bulletin F28/32-151, Revision 1, dated March 12, 1997,
references Fokker F.28 Airplane Maintenance Manual (AMM), Chapter
32-10-04, as an additional source of service information to
accomplish the actions required by this AD.
[[Page 50132]]
(b) Within 3,000 flight cycles after the effective date of this
AD, perform a visual inspection of the MLG assembly for excessive
free play, in accordance with Parts 1.A., 1.B., and 1.C. of the
Accomplishment Instructions of Fokker Service Bulletin F28/32-151,
Revision 1, dated March 12, 1997.
(1) If no discrepancy is detected, repeat the visual inspection
thereafter at intervals not to exceed 3,000 flight cycles.
(2) If any discrepancy is detected, prior to further flight,
correct the discrepant condition in accordance with Parts 1.A.,
1.B., and/or 1.C. of the Accomplishment Instructions of the service
bulletin, as applicable. Repeat the visual inspection thereafter at
intervals not to exceed 3,000 flight cycles.
Note 3: Parts 1.A., 1.B., and 1.C. of the Accomplishment
Instructions of Fokker Service Bulletin F28/32-151, Revision 1,
dated March 12, 1997, reference Fokker F.28 AMM, Chapters 32-10-01,
32-10-00, and 32-10-04, as additional sources of service information
to accomplish the actions required by this AD.
(c) Within 30 months after the effective date of this AD,
accomplish paragraphs (c)(1) and (c)(2) of this AD.
(1) Install torque link dampers and associated sub-assemblies in
accordance with Part 2 of the Accomplishment Instructions of Fokker
Service Bulletin F28/32-151, Revision 1, dated March 12, 1997.
Accomplishment of the installation constitutes terminating action
for the repetitive inspection requirements of this AD.
(2) Revise the FAA-approved maintenance program to incorporate a
visual inspection of the oil level of the torque-link dampers
thereafter at intervals not to exceed 250 flight hours, and
incorporate a scheduled overhaul of each damper concurrent with the
overhaul of the MLG on which it is installed, in accordance with
Part 2 of the Accomplishment Instructions of Fokker Service Bulletin
F28/32-151, Revision 1, dated March 12, 1997.
Note 4: After the maintenance program is revised to include the
required inspection and overhaul actions in accordance with
paragraph (c)(2) of this AD, operators do not need to make a
maintenance log entry to show compliance with this AD each time
those actions are accomplished thereafter.
(d) 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, International Branch, ANM-116, 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, International
Branch, ANM-116.
Note 5: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the International Branch, ANM-116.
(e) 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.
(f) The actions shall be done in accordance with Fokker Service
Bulletin F28/32-151, Revision 1, dated March 12, 1997, which
includes the following list of effective pages:
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Revision level
Page No. shown on page Date shown on page
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1-6, 10........................ 1.................. March 12, 1997.
7-9, 11-13..................... Original........... August 9, 1996.
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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 Fokker Services B.V., Technical Support
Department, P.O. Box 75047, 1117 ZN Schiphol Airport, the Netherlands.
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.
Note 6: The subject of this AD is addressed in Dutch
airworthiness directive BLA 1996-103(A), dated August 30, 1996.
(g) This amendment becomes effective on October 26, 1998.
Issued in Renton, Washington, on September 11, 1998.
Dorenda D. Baker,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 98-24902 Filed 9-18-98; 8:45 am]
BILLING CODE 4910-13-U
