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[Federal Register Volume 62, Number 29 (Wednesday, February 12, 1997)]
[Rules and Regulations]
[Pages 6457-6458]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-3026]

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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 96-NM-69-AD; Amendment 39-9923; AD 97-03-18]
RIN 2120-AA64

Airworthiness Directives; Saab Model SAAB SF340A, SAAB 340B, and 
SAAB 2000 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 Saab Model SAAB SF340A, SAAB 340B, and SAAB 2000 
series airplanes, that requires replacement of the hubcap drive 
coupling of the main wheel with an improved coupling. This amendment is 
prompted by reports of unexpected decreases in the pressure of the main 
wheel brake due to incorrect engagement between the main wheel coupling 
and the wheel speed transducer, which can result in false signals being 
sent to the anti-skid control box. The actions specified by this AD are 
intended to prevent loss of brake effectiveness due to a decrease in 
the pressure of the main wheel brake.

DATES: Effective March 19, 1997.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of March 19, 1997.

ADDRESSES: 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 
Federal Aviation Administration (FAA), Transport Airplane Directorate, 
Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, 
Transport Airplane Directorate, Los Angeles Aircraft Certification 
Office, 3960 Paramount Boulevard, Lakewood, California; or at the 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Walter Eierman, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft 
Certification Office, 3960 Paramount Boulevard, Lakewood, California 
90712; telephone (310) 627-5336; fax (310) 627-5210.

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 Saab Model SAAB SF340A, 
SAAB 340B, and SAAB 2000 series airplanes was published in the Federal 
Register on September 4, 1996 (61 FR 46572). That action proposed to 
require replacement of the hubcap drive coupling of the main wheel with 
an improved coupling.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were submitted in response 
to the proposal or the FAA's determination of the cost to the public.

[[Page 6458]]

Conclusion

    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 235 Model SAAB SF340A and SAAB 340B series 
airplanes and 3 Model SAAB 2000 series airplanes of U.S. registry will 
be affected by this AD.
    For Model SAAB SF340A and SAAB 340B series airplanes, it will take 
approximately 2 work hours per airplane to accomplish the required 
actions, at an average labor rate of $60 per work hour. Required parts 
will cost approximately $200 per airplane. Based on these figures, the 
cost impact of the AD on U.S. operators of Model SAAB 340A and SAAB 
340B series airplanes is estimated to be $75,200, or $320 per airplane.
    For Model SAAB 2000 series airplanes, it will take approximately 2 
work hours per airplane to accomplish the required actions, at an 
average labor rate of $60 per work hour. Required parts will cost 
approximately $120 per airplane. Based on these figures, the cost 
impact of the proposed AD on U.S. operators of Model SAAB 2000 series 
airplanes is estimated to be $720, or $240 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:

97-03-18  SAAB AIRCRAFT AB: Amendment 39-9923. Docket 96-NM-69-AD.

    Applicability: Model SAAB SF340A series airplanes having serial 
numbers 004 through 159 inclusive; Model SAAB 340B series airplanes 
having serial numbers 160 through 378 inclusive; and Model SAAB 2000 
series airplanes having serial numbers 002 through 029 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 
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 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 loss of brake effectiveness due to a decrease in 
pressure of the main wheel brake, accomplish the following:
    (a) Within 90 days after the effective date of this AD, replace 
each main wheel hubcap drive coupling having part number (P/N) 40-
91115 with a main wheel hubcap drive coupling having P/N 40-91115, 
Rev. D, in accordance with Saab Service Bulletin SAAB 340-32-107, 
dated January 18, 1996 (for Model SAAB SF340A and SAAB 340B series 
airplanes), or Saab Service Bulletin SAAB 2000-32-019, dated January 
18, 1996 (for Model SAAB 2000 series airplanes), as applicable.

    Note 2: The Saab service bulletins reference Crane Hydro-Aire 
Division Service Bulletins 140-041-32-1 (for wheel hubcaps having 
part number 140-04120) and 140-159-32-1 (for wheel hubcaps having 
part number 140-15920), both dated December 21, 1995, as additional 
sources of service information for replacement of the hubcap drive 
coupling.

    (b) As of the effective date of this AD, no person shall install 
on any airplane a main wheel hubcap drive coupling having P/N 40-
91115 in a wheel hubcap having P/N 140-04120 (for Model SAAB SF340A 
and SAAB 340B series airplanes), or P/N 140-15920 (for Model SAAB 
2000 series airplanes), as applicable.
    (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, Los Angeles 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, Los Angeles ACO.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Los Angeles ACO.

    (d) 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.
    (e) The replacement shall be done in accordance with Saab 
Service Bulletin SAAB 340-32-107, dated January 18, 1996, or Saab 
Service Bulletin SAAB 2000-32-019, dated January 18, 1996, as 
applicable. 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 FAA, Transport 
Airplane Directorate, Los Angeles Aircraft Certification Office, 
3960 Paramount Boulevard, Lakewood, California; or at the Office of 
the Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.
    (f) This amendment becomes effective on March 19, 1997.

    Issued in Renton, Washington, on January 31, 1997.
Darrell M. Pederson,
 Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-3026 Filed 2-11-97; 8:45 am]
BILLING CODE 4910-13-U
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