[Federal Register Volume 63, Number 50 (Monday, March 16, 1998)]
[Rules and Regulations]
[Pages 12611-12613]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-6502]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 95-NM-38-AD; Amendment 39-10393; AD 98-06-15]
RIN 2120-AA64
Airworthiness Directives; Fokker Model F28 Mark 0100 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 Fokker Model F28 Mark 0100 series airplanes, that
requires replacement of the return filter diaphragm assemblies on
hydraulic systems 1 and 2 with modified filter units having new
diaphragms. This amendment is prompted by a report of insufficient
running clearance of the brake units due to overpressure in the
hydraulic return system; this condition could lead to brake
overheating. The actions specified by this AD are intended to prevent
too high pressure in the hydraulic return system during the selection
of subsystem(s), which could result in inadvertent braking and/or blown
tires.
DATES: Effective April 20, 1998.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of April 20, 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 certain Fokker Model F28 Mark 0100
series airplanes was published in the Federal Register on May 25, 1995
(60 FR 27704). That action proposed to require replacement of the
return filter diaphragm assemblies on hydraulic systems 1 and 2 with
modified filter units having new diaphragms.
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 Withdraw Proposed AD
The Air Transport Association (ATA) of America, on behalf of one
member, requests that the proposed AD be withdrawn because the
corrective action specified in the referenced Fokker Service Bulletin
SBF100-29-025, dated December 31, 1993, is ineffectual in preventing
overpressure of the subject hydraulic return system.
The FAA does not concur with the commenter's request to withdraw
the proposal. The Rijksluchtvaartdienst (RLD), which is the
airworthiness authority for the Netherlands, has advised the FAA that
there have been no additional reports of discrepancies in the system
since the service bulletin was issued. In addition, the commenter
provides no justification to substantiate the claim that the corrective
action is ineffectual. Based on this information, the FAA has
determined that the modification specified in Fokker Service Bulletin
SBF100-29-025, dated December 31, 1993, adequately addresses the unsafe
condition.
Request To Extend Compliance Time
One commenter requests an extension of the proposed compliance time
of 6 months, but provides no specific extension time. The commenter's
request is based on the number of airplanes in its fleet and the time
required to accomplish the action. The commenter expresses concern that
it may not be able to modify all airplanes in 6 months.
The FAA does not concur with the request for an extension of the
compliance time. In developing the compliance time, the FAA considered
the safety implications, parts availability, and normal maintenance
schedules. In consideration of all these factors, and the time since
the Notice of Proposed Rulemaking (NPRM) was published, the FAA has
determined that the compliance time, as proposed, represents an
appropriate interval to complete the necessary replacement.
Request to Revise Unsafe Condition
One commenter, the manufacturer, requests that the description of
the cause of the addressed unsafe condition that appeared in the
proposed AD be clarified. The unsafe condition that appears in the
proposal reads as follows: ``* * * to prevent overpressure in the
hydraulic return system which could result in reduced braking
performance and/or blown tires due to brake overheating.'' The
commenter suggests that a more accurate description would be ``* * * to
prevent too high pressure in the hydraulic return system during the
selection of the subsystem(s), which could result in inadvertent
braking and/or blown tires.'' The manufacturer states that its service
bulletin was issued following an incident in which all four tires blew
on touchdown. During a taxi check, following the replacement of several
components, inspections revealed a brake problem. It was found that the
brakes locked as soon as the flaps moved to a new position and unlocked
as soon as the flaps stopped moving.
[[Page 12612]]
The FAA concurs. Based on the information provided by the
manufacturer following further investigation into the incident, the FAA
has revised the unsafe condition in this final rule to reflect the
commenter's suggestion.
Request for Inclusion of Operator Modification as Alternative
Method of Compliance
One commenter requests that the FAA revise the proposed AD to
include its own modification as an acceptable alternative method of
compliance for replacing the diaphragms with filter element retaining
spacers. The commenter, in collaboration with Fokker and PALL-APME, has
developed a new modification, which it believes satisfactorily
addresses the safety objective of the proposed AD. The commenter is of
the opinion that if an AD is issued, it should include that
modification as an acceptable means of compliance. The commenter also
states that the applicability of the proposed AD should not include
those aircraft on which units having modified part numbers designated
by -1 are installed.
The FAA does not concur that the modification suggested by the
commenter should be incorporated in this final rule, or that airplanes
on which the modified part numbers designated by ``-1'' are installed
should be excluded from the applicability. The FAA does not consider it
appropriate to include various provisions in an AD applicable to a
single operator's unique modification. However, paragraph (c) of this
AD contains a provision for requesting approval of an alternative
method of compliance to address these types of individual
circumstances.
Request To Revise Cost Impact Information
One commenter, the manufacturer, requests that the cost impact
information, below, be revised to reflect that only 79 airplanes of
U.S. registry are affected by the proposed AD. The change is requested
based on the most current information available to the manufacturer.
The FAA concurs and has revised the cost impact information, below,
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 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
The FAA estimates that 79 Model F28 Mark 0100 series airplanes of
U.S. registry will be affected by this AD, that it will take
approximately 2 work hours per airplane to accomplish the required
actions, and that the average labor rate is $60 per work hour. Required
parts will be provided by the parts manufacturer at no cost to
operators. Based on these figures, the cost impact of the AD on U.S.
operators is estimated to be $9,480, or $120 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.
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:
98-06-15 Fokker: Amendment 39-10393. Docket 95-NM-38-AD.
Applicability: Model F28 Mark 0100 series airplanes equipped
with Aircraft Porous Media Europe (APME) Limited hydraulic return
filter assemblies having part numbers (P/N) QA07236 and QA07237, all
serial numbers; 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 (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 too high pressure in the hydraulic return system
during the selection of subsystem(s), which could result in
inadvertent braking and/or blown tires, accomplish the following:
(a) Within 6 months after the effective date of this AD, replace
the return filters, P/N's QA07236 and QA07237, on hydraulic systems
1 and 2, respectively, with modified return filter units, in
accordance with Fokker Service Bulletin SBF100-29-025, dated
December 31, 1993.
(b) As of the effective date of this AD, no person shall install
on any airplane a return filter unit, P/N QA07236 or QA07237, on
hydraulic system 1 or 2, respectively, unless that unit has been
modified in accordance with Fokker Service Bulletin SBF100-29-025,
dated December 31, 1993.
(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, 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.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the International Branch, ANM-116.
(d) Special flight permits may be issued in accordance with
sections 21.197 and 21.199
[[Page 12613]]
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.
(e) The replacement shall be done in accordance with Fokker
Service Bulletin SBF100-29-025, dated December 31, 1993. 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 3: The subject of this AD is addressed in Dutch
airworthiness directive 94-024 (A), dated January 28, 1994.
(f) This amendment becomes effective on April 20, 1998.
Issued in Renton, Washington, on March 9, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 98-6502 Filed 3-13-98; 8:45 am]
BILLING CODE 4910-13-U