[Federal Register Volume 60, Number 205 (Tuesday, October 24, 1995)]
[Rules and Regulations]
[Pages 54419-54421]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-25989]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 95-NM-187-AD; Amendment 39-9412; AD 95-22-05]
Airworthiness Directives; Saab Model SAAB SF340A and SAAB 340B
Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This amendment adopts a new airworthiness directive (AD) that
is applicable to certain Saab Model SAAB SF340A and SAAB 340B series
airplanes. This action requires repetitive inspections to detect damage
of the brake assembly and wheel assembly; repair, if necessary; and
installation of a heat shield. This action also provides for an
optional installation which, if accomplished, constitutes terminating
action for the repetitive inspections. This amendment is prompted by
reports of failure of the brake assembly due to separation of the
stator clips from the stator disk. The actions specified in this AD are
intended to prevent failure of the brake assembly, which could result
in a brake fire.
DATES: Effective November 8, 1995.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of November 8, 1995.
Comments for inclusion in the Rules Docket must be received on or
before December 26, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 95-NM-187-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056.
The service information referenced in this AD may be obtained from
SAAB Aircraft AB, SAAB Aircraft Product Support, S-581.88, Linkoping,
Sweden. This information may be examined 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.
FOR FURTHER INFORMATION CONTACT: Ruth E. Harder, Aerospace Engineer,
[[Page 54420]]
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206)
227-1721; fax (206) 227-1149.
SUPPLEMENTARY INFORMATION: The Luftfartsverket (LFV), which is the
airworthiness authority for Sweden, recently notified the FAA that an
unsafe condition may exist on certain Saab Model SAAB SF340A and SAAB
340B series airplanes. The LFV advises that it has received several
reports indicating that the brake assembly failed on several of these
airplanes. Investigation revealed that the cause of the failures of the
brake assemblies was due to separation of the stator clips from the
stator disk. (The stator clip is a steel component that attaches to the
stator lug to offer better resistance to damage of the drive face of
the lug.) Brake assemblies having part numbers 5012589, 5007219-1,
5008541, 5008541-1, and 5008541-2 have been identified as those
susceptible to such failure.
In certain reported instances, these separated clips migrated
through the torque tube lightening hole and became trapped between the
torque tube and the wheel hub. In at least one case, this resulted in a
cut through the hub, leakage of hydraulic fluid on the hot brakes, and
subsequent brake fire fueled by hydraulic fluid. In other reported
incidents, the separated clips migrated through the carbon stack and
resulted in brake damage or disintegration.
These conditions, if not detected, could result in brake and wheel
failure, which could lead to a brake fire.
Saab has issued Service Bulletin 340-32-105, dated September 5,
1995, which describes procedures for repetitive visual inspections to
detect damage of the brake assembly and wheel assembly, repair of
damaged assemblies, and installation of a heat shield in the torque
tube. The LFV classified this service bulletin as mandatory and issued
Swedish airworthiness directive SAD 1-075, dated September 7, 1995, in
order to assure the continued airworthiness of these airplanes in
Sweden.
This airplane model is manufactured in Sweden and is type
certificated for operation in the United States under the provisions of
section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and
the applicable bilateral airworthiness agreement. Pursuant to this
bilateral airworthiness agreement, the LFV has kept the FAA informed of
the situation described above. The FAA has examined the findings of the
LFV, reviewed all available information, and determined that AD action
is necessary for products of this type design that are certificated for
operation in the United States.
Since an unsafe condition has been identified that is likely to
exist or develop on other airplanes of the same type design registered
in the United States, this AD is being issued to prevent failure of the
brake assembly, which could result in a brake fire. This AD requires
repetitive visual inspections to detect damage of the brake assembly
and wheel assembly, repair of any damaged brake assembly or wheel
assembly found, and installation of a heat shield. The actions are
required to be accomplished in accordance with the service bulletin
described previously.
This AD also provides for termination of the repetitive visual
inspections by installing a redesigned stator clip. This installation
is to be accomplished in accordance with a method approved by the FAA.
This is considered to be interim action. The manufacturer has
advised that it is currently developing a modified stator clip that
will positively address the unsafe condition addressed by this AD. Once
this redesigned clip is developed, approved, and available, the FAA may
consider additional rulemaking.
Since a situation exists that requires the immediate adoption of
this regulation, it is found that notice and opportunity for prior
public comment hereon are impracticable, and that good cause exists for
making this amendment effective in less than 30 days.
Comments Invited
Although this action is in the form of a final rule that involves
requirements affecting flight safety and, thus, was not preceded by
notice and an opportunity for public comment, comments are invited on
this rule. Interested persons are invited to comment on this rule by
submitting such written data, views, or arguments as they may desire.
Communications shall identify the Rules Docket number and be submitted
in triplicate to the address specified under the caption ADDRESSES. All
communications received on or before the closing date for comments will
be considered, and this rule may be amended in light of the comments
received. Factual information that supports the commenter's ideas and
suggestions is extremely helpful in evaluating the effectiveness of the
AD action and determining whether additional rulemaking action would be
needed.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the rule that might
suggest a need to modify the rule. All comments submitted will be
available, both before and after the closing date for comments, in the
Rules Docket for examination by interested persons. A report that
summarizes each FAA-public contact concerned with the substance of this
AD will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this rule must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 95-NM-187-AD.'' The postcard will be date stamped and
returned to the commenter.
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.
The FAA has determined that this regulation is an emergency
regulation that must be issued immediately to correct an unsafe
condition in aircraft, and that it is not a ``significant regulatory
action'' under Executive Order 12866. It has been determined further
that this action involves an emergency regulation under DOT Regulatory
Policies and Procedures (44 FR 11034, February 26, 1979). If it is
determined that this emergency regulation otherwise would be
significant under DOT Regulatory Policies and Procedures, a final
regulatory evaluation will be prepared and placed in the Rules Docket.
A copy of it, if filed, 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:
[[Page 54421]]
Authority: 49 U.S.C. 106(g), 40101, 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
95-22-05 Saab Aircraft AB: Amendment 39-9412. Docket 95-NM-187-AD.
Applicability: Model SAAB SF340A series airplanes having serial
numbers 004 through 159, inclusive; and Model SAAB 340B series
airplanes having serial numbers 160 and subsequent; equipped with
brake assemblies having part number 5012589, 5007219-1, 5008541,
5008541-1, or 5008541-2; certificated in any category.
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
otherwise 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 use the authority
provided in paragraph (d) of this AD to request approval from the
FAA. This approval may address either no action, if the current
configuration eliminates the unsafe condition; or different actions
necessary to address the unsafe condition described in this AD. Such
a request should include an assessment of the effect of the changed
configuration on the unsafe condition addressed by this AD. In no
case does the presence of any modification, alteration, or repair
remove any airplane from the applicability of this AD.
Compliance: Required as indicated, unless accomplished
previously.
To prevent failure of the brake assembly and wheel assembly,
which could result in the potential for a brake fire, accomplish the
following:
(a) Within 10 days after the effective date of this AD, perform
a visual inspection to detect damage of the brake assembly and wheel
assembly in accordance with Saab Service Bulletin 340-32-105, dated
September 5, 1995.
(1) If no damage is detected, repeat the inspection thereafter
at intervals not to exceed 225 hours time-in-service.
(2) If any damage is detected, prior to further flight, repair
the damaged brake assembly and/or wheel assembly in accordance with
the service bulletin. Repeat the inspection thereafter at intervals
not to exceed 225 hours time-in-service.
(b) Within 225 hours time-in-service after accomplishing the
inspection required by paragraph (a) of this AD, install a heat
shield in the torque tube in accordance with Saab Service Bulletin
340-32-105, dated September 5, 1995.
(c) Installation of a redesigned stator clip in accordance with
a method approved by the Manager, Standardization Branch, ANM-113,
FAA, Transport Airplane Directorate, constitutes terminating action
for the repetitive inspections required by paragraph (a) of this AD.
(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, Standardization Branch, ANM-113,
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,
Standardization Branch, ANM-113.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Standardization Branch, ANM-113.
(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 inspections, repair, and installation of a heat shield
shall be done in accordance with Saab Service Bulletin 340-32-105,
dated September 5, 1995. 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 SAAB
Aircraft AB, SAAB Aircraft Product Support, S-581.88, Linkoping,
Sweden. 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.
(g) This amendment becomes effective on November 8, 1995.
Issued in Renton, Washington, on October 16, 1995.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-25989 Filed 10-23-95; 8:45 am]
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