[Federal Register Volume 62, Number 148 (Friday, August 1, 1997)]
[Rules and Regulations]
[Pages 41259-41260]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-20128]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-NM-130-AD; Amendment 39-10095; AD 97-16-04]
RIN 2120-AA64


Airworthiness Directives; Saab Model SAAB SF340A and SAAB 340B 
Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD), applicable to certain Saab Model SAAB SF340A and SAAB 340B series 
airplanes, that currently requires inspections to detect improper 
connections of the wire harness installation to the cartridges of the 
fire extinguishers in the engine nacelles, correction of any 
discrepancy, and modification of the wiring. This amendment adds a 
revised modification of that wiring, which, if accomplished, would 
terminate the inspections currently required by the existing AD. This 
amendment is prompted by reports indicating that, due to the removal of 
a certain clamp during maintenance, these fire extinguisher cartridges 
still could be connected incorrectly after the modification required by 
the existing AD has been accomplished. The actions specified by this AD 
are intended to prevent incorrect wiring of the cartridges, which would 
result in inability of the fire extinguishers to jointly discharge 
extinguishing agent into a nacelle in the event of an engine fire.

DATES: Effective September 5, 1997.
    The incorporation by reference of Saab Service Bulletin SAAB 340-
26-015, evision 1, dated December 8, 1995, as listed in the 
regulations, is approved by the Director of the Federal Register as of 
September 5, 1997.
    The incorporation by reference of Saab Service Bulletin SAAB 340-
26-012, evision 1, dated October 5, 1993, as listed in the regulations, 
was approved previously by the Director of the Federal Register as of 
February 16, 1994 (59 FR 4575, February 1, 1994).

ADDRESSES: The service information referenced in this AD may be 
obtained from Saab Aircraft AB, SAAB Aircraft Product Support, S-
581.88, Linkping, 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 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Ruth Harder, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-1721; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) by superseding AD 94-03-06, 
amendment 39-8813 (59 FR 4575, February 1, 1994), which is applicable 
to certain Saab Model SAAB SF340A and SAAB 340B series airplanes, was 
published in the Federal Register on April 9, 1997 (62 FR 17127). The 
action proposed to continue to require repetitive inspections to detect 
improper connections of the wire harness installation to the cartridges 
of the fire extinguishers in the engine nacelles, and correction of any 
discrepancies. The action also proposed to require a revised 
modification of the wiring to one of the electrical connectors if it 
exceeds a certain length. Accomplishment of the modification would 
terminate the repetitive inspections of the wiring currently required 
by AD 94-03-06.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the single comment received.
    The commenter supports the proposed rule.

Conclusion

    After careful review of the available data, including the comment 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule as proposed.

Cost Impact

    There are approximately 235 Saab Model SAAB SF340A and SAAB 340B 
series airplanes of U.S. registry that will be affected by this AD.
    The actions that are currently required by AD 94-03-06 take 
approximately 6 work hours per airplane to accomplish, at an average 
labor rate of $60 per work hour. Based on these figures, the cost 
impact of the previously required actions on U.S. operators is 
estimated to be $77,760, or $360 per airplane. (At the time AD 94-03-06 
went into effect, it was estimated that 216 airplanes would be 
affected.)
    The new actions that are required by this new AD will take 
approximately 6 work hours per airplane to accomplish, at an average 
labor rate of $60 per work hour. Required parts will be provided at no 
cost to operators. Based on these figures, the cost impact of the new 
requirements of this AD on U.S. operators is estimated to be $84,600, 
or $360 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

[[Page 41260]]

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 removing amendment 39-8813 (59 FR 
4575, February 1, 1994), and by adding a new airworthiness directive 
(AD), amendment 39-10095, to read as follows:

97-16-04  SAAB Aircraft AB: Amendment 39-10095. Docket 96-NM-130-AD. 
Supersedes AD 94-03-06, Amendment 39-8813.

    Applicability: Model SAAB SF340A series airplanes having serial 
numbers 004 through 159 inclusive; and Model SAAB 340B series 
airplanes having serial numbers 160 through 345 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 (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 incorrect wiring of the wire harness installation to 
the fire extinguisher cartridges in the engine nacelles, which would 
result in the inability of the fire extinguishers to jointly 
discharge agent into a nacelle in the event of a fire, accomplish 
the following:
    (a) Within 25 days after February 16, 1994 (the effective date 
of AD 94-03-06, amendment 39-8813), perform an inspection to ensure 
proper connections of the wire harness installation to the engine 
nacelle fire extinguisher, in accordance with Saab Service Bulletin 
SAAB 340-26-012, Revision 1, dated October 5, 1993, or Saab Service 
Bulletin SAAB 340-26-015, Revision 1, dated December 8, 1995. Prior 
to further flight, correct any discrepancy found and modify the 
wiring, in accordance with the service bulletin. After the effective 
date of this AD, perform this inspection and correct any discrepancy 
found, in accordance with Saab Service Bulletin SAAB 340-26-015, 
Revision 1, dated December 8, 1995.
    (b) Repeat the inspection specified in paragraph (a) of this AD 
immediately following any maintenance action during which both 
electric connectors to either of the fire extinguishers in the 
nacelle electrical bays are disconnected.
    (c) Prior to the accumulation of 4,000 hours time-in-service 
after the effective date of this AD, or at the next scheduled 
maintenance inspection after the effective date of this AD, 
whichever occurs earlier:
    (1) Conduct an inspection to ensure proper connection of the 
wire harness installation to the fire extinguisher cartridges in 
both engine nacelles, in accordance with Saab Service Bulletin SAAB 
340-26-015, Revision 1, dated December 8, 1995. If any discrepancy 
is detected, prior to further flight, correct this discrepancy in 
accordance with the service bulletin.
    (2) After the inspection required by paragraph (c)(1) of this AD 
has been accomplished, measure the total length of the wiring 
harness from the clamp to connector 9WB-P2/10WB-P2, in accordance 
with Saab Service Bulletin SAAB 340-26-015, Revision 1, dated 
December 8, 1995. If the wiring harness has been modified with a 
loop in accordance with the requirements of paragraph (a) of this 
AD, or in accordance with Saab Service Bulletin SAAB 340-26-012, 
Revision 1, dated October 5, 1993, before measuring, remove the loop 
in the wire harness in accordance with Saab Service Bulletin SAAB 
340-26-015, Revision 1, dated December 8, 1995.
    (i) If the total length is 7 inches (180mm) or less, no further 
action is required by this AD.
    (ii) If the total length exceeds 7 inches (180mm), modify this 
wiring in accordance with Saab Service Bulletin SAAB 340-26-015, 
Revision 1, dated December 8, 1995. Accomplishment of this 
modification constitutes terminating action for the repetitive 
inspections required by paragraph (b) of this AD, and no further 
action is required by this AD.

    Note 2: Accomplishment of this modification in accordance with 
Saab Service Bulletin SAAB 340-26-015, dated November 23, 1995, 
prior to the effective date of this AD, is considered acceptable for 
compliance with the requirements of paragraph (c)(2)(ii) 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 3: 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 actions shall be done in accordance with Saab Service 
Bulletin SAAB 340-26-012, Revision 1, dated October 5, 1993, and/or 
Saab Service Bulletin SAAB 340-26-015, Revision 1, dated December 8, 
1995. The incorporation by reference of Saab Service Bulletin SAAB 
340-26-012, Revision 1, dated October 5, 1993, was approved 
previously by the Director of the Federal Register, in accordance 
with 5 U.S.C. 552(a) and 1 CFR part 51, as of February 16, 1994 (59 
FR 4575, February 1, 1994). The incorporation by reference of Saab 
Service Bulletin SAAB 340-26-015, Revision 1, dated December 8, 
1995, is 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 the Office of the Federal Register, 800 North Capitol 
Street, NW., suite 700, Washington, DC.
    (g) This amendment becomes effective on September 5, 1997.

    Issued in Renton, Washington, on July 25, 1997.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-20128 Filed 7-31-97; 8:45 am]
BILLING CODE 4910-13-U