[Federal Register Volume 59, Number 9 (Thursday, January 13, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-831]
[[Page Unknown]]
[Federal Register: January 13, 1994]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 93-NM-137-AD; Amendment 39-8778; AD 93-25-14]
Airworthiness Directives; SAAB-Scania Model SF340A and SAAB 340B
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-Scania Model SF340A and SAAB 340B series
airplanes, that requires replacement of the left- and right-hand AC
generator control relays with new relays at the generator control
positions. This amendment is prompted by reports that in-service AC
generator control relays, specifically used for generator transfer
functions, have failed where the main contacts arced. The actions
specified by this AD are intended to prevent loss of AC electrical
power, and local area damage that may lead to further electrical
failures and smoke in the cockpit.
DATES: Effective February 14, 1994.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of February 14, 1994.
ADDRESSES: The service information referenced in this AD may be
obtained from SAAB-Scania AB, SAAB Aircraft Support Product, 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 Office of
the Federal Register, 800 North Capitol Street, NW., suite 700,
Washington, DC.
FOR FURTHER INFORMATION CONTACT: Mark Quam, Aerospace Engineer,
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,
1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone (206)
227-2145; fax (206) 227-1320.
SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal
Aviation Regulations to include an airworthiness directive (AD) that is
applicable to certain SAAB-Scania Model SF340A and SAAB 340B series
airplanes was published in the Federal Register on September 14, 1993
(58 FR 48010). That action proposed to require replacement of the left-
and right-hand AC generator control relays, part number (P/N) SM15CXD1,
with new relays, P/N SM15CXD4, at the generator control positions (7XA/
8XA).
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.
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.
The FAA estimates that 200 airplanes of U.S. registry will be
affected by this AD, that it will take approximately 2.5 work hours per
airplane to accomplish the required actions, and that the average labor
rate is $55 per work hour. Required parts will be supplied by the
manufacturer at no cost to the operators. Based on these figures, the
total cost impact of the AD on U.S. operators is estimated to be
$27,500, or $137.50 per airplane. This total cost figure assumes that
no operator has yet accomplished the requirements of this AD.
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 14 CFR part
39 of the Federal Aviation Regulations as follows:
PART 39--AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C.
106(g); and 14 CFR 11.89.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
93-25-14 SAAB-Scania: Amendment 39-8778. Docket 93-NM-137-AD.
Applicability: Model SAAB SF340A series airplanes, serial
numbers 004 through 159 inclusive; and Model SAAB 340B series
airplanes, serial numbers 160 through 325 inclusive; certificated in
any category.
Compliance: Required as indicated, unless accomplished
previously.
To prevent loss of AC electrical power, and local area damage
that may lead to further electrical failures and smoke in the
cockpit, accomplish the following:
(a) Within 6 months after the effective date of this AD, replace
the left- and right-hand AC generator control relays, part number
(P/N) SM15CXD1, with new relays, P/N SM15CXD4, at generator control
positions 7XA and 8XA, in accordance with SAAB 340 Service Bulletin
SAAB 340-24-022, dated October 21, 1992.
(b) As of the effective date of this AD, no person shall install
an AC generator control relay, P/N SM15CXD1, at generator control
positions 7XA or 8XA on any airplane.
(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, 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: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Standardization Branch, ANM-113.
(d) Special flight permits may be issued in accordance with FAR
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 340
Service Bulletin SAAB 340-24-022, dated October 21, 1992. 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-Scania AB, SAAB Aircraft
Support Product, 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.
(f) This amendment becomes effective on February 14, 1994.
Issued in Renton, Washington, on December 21, 1993.
James V. Devany,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 94-831 Filed 1-12-94; 8:45 am]
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