[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]
BILLING CODE 4910-13-U