AD 2004-09-35

final rule

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

AD Number
2004-09-35
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 2002-NM-146-AD
FR Citation
69 FR 26000
Technical illustration of an aircraft electrical generator and wiring assembly
Problem area Electrical system

Applicability

TypeManufacturerModelDetails
aircraft Saab AB, Saab Aerosystems SAAB 340B Airworthiness Directives; Saab Model SAAB SF340A and SAAB 340B Series Airplanes
aircraft Saab AB, Saab Aerosystems 340A (SAAB SF340A) Airworthiness Directives; Saab Model SAAB SF340A and SAAB 340B Series Airplanes

Unsafe Condition

Loss of DC generators due to the presence of DC over-voltage/feeder-fault test switches, which could result in the loss of normal electrical power and increased pilot workload.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Remove the two DC over-voltage/feeder-fault test switches from the Test 2 Panel of the generator control unit. Follow-on actions as specified in the AD must also be completed.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Before further flight

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Saab Model SAAB SF340A and SAAB 340B series airplanes, as specified in the AD.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

This amendment adopts a new airworthiness directive (AD), applicable to certain Saab Model SAAB SF340A and SAAB 340B series airplanes, that requires removing the two direct current (DC) over- voltage/feeder-fault test switches from the Test 2 Panel of the generator control unit, and follow-on actions. This action is necessary to prevent loss of the DC generators, which could result in the loss of normal electrical power to the airplane and increased pilot workload. This action is intended to address the identified unsafe condition.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 69, Number 91 (Tuesday, May 11, 2004)]
[Rules and Regulations]
[Pages 26000-26001]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 04-10373]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NM-146-AD; Amendment 39-13626; AD 2004-09-35]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Saab Model SAAB SF340A and SAAB 340B series 
airplanes, that requires removing the two direct current (DC) over-
voltage/feeder-fault test switches from the Test 2 Panel of the 
generator control unit, and follow-on actions. This action is necessary 
to prevent loss of the DC generators, which could result in the loss of 
normal electrical power to the airplane and increased pilot workload. 
This action is intended to address the identified unsafe condition.

DATES: Effective June 15, 2004.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of June 15, 2004.

ADDRESSES: The service information referenced in this AD may be 
obtained from Saab Aircraft AB, SAAB Aircraft Product Support, S-
581.88, Link[ouml]ping, 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 
National Archives and Records Administration (NARA). For information on 
the availability of this material at NARA, call (202) 741-6030, or go 
to: <a href="http://www.archives">http://www.archives</a>.gov/federal--register/code--of--federal--
regulations/ibr--locations.html.

FOR FURTHER INFORMATION CONTACT: Rosanne Ryburn, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2139; fax (425) 227-1149.

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 and 
SAAB 340B series airplanes was published in the Federal Register on 
October 30, 2003 (68 FR 61774). That action proposed to require 
removing the two direct current (DC) over-voltage/feeder-fault test 
switches from the Test 2 Panel of the generator control unit, and 
follow-on actions.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comment received.
    The commenter requests that a credit paragraph be added to the 
proposed AD for accomplishment of the specified actions per Saab 
Service Bulletin 340-24-023, Revision 01, dated August 24, 1995. 
(Revision 02 of the service bulletin was referenced in the proposed AD 
for accomplishment of the actions.) The FAA agrees with the commenter, 
as the procedures specified in Revision 01 are essentially the same as 
those in Revision 02. We have added a new paragraph (b) to this final 
rule to provide credit for actions accomplished previously per Revision 
01 of the referenced service bulletin.

Conclusion

    After careful review of the available data, including the comment 
noted above, we have determined that air safety and the public interest 
require the

[[Page 26001]]

adoption of the rule with the change described previously. We have 
determined that this change will neither increase the economic burden 
on any operator nor increase the scope of the AD.

Cost Impact

    The FAA estimates that 251 airplanes of U.S. registry will be 
affected by this AD, that it will take about 4 work hours per airplane 
to accomplish the required actions, and that the average labor rate is 
$65 per work hour. Required parts will cost about $107 per airplane. 
Based on these figures, the cost impact of the AD on U.S. operators is 
estimated to be $92,117, or $367 per airplane.
    The cost impact figure discussed above is 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. The cost impact figures discussed 
in AD rulemaking actions represent only the time necessary to perform 
the specific actions actually required by the AD. These figures 
typically do not include incidental costs, such as the time required to 
gain access and close up, planning time, or time necessitated by other 
administrative actions.

Regulatory Impact

    The regulations adopted herein will not have a substantial direct 
effect 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, it 
is determined that this final rule does not have federalism 
implications under Executive Order 13132.
    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

0
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

0
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]

0
2. Section 39.13 is amended by adding the following new airworthiness 
directive:

2004-09-35 Saab Aircraft AB: Amendment 39-13626. Docket 2002-NM-146-
AD.

    Applicability: Model SAAB SF340A series airplanes having serial 
numbers 004 through 159 inclusive; and SAAB 340B series airplanes 
having serial numbers 160 through 379 inclusive; certificated in any 
category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent the loss of the direct current (DC) generators, which 
could result in the loss of normal electrical power to the airplane 
and increased pilot workload, accomplish the following:

Removal of DC Generator Test Switches

    (a) Within 5,000 flight hours or two years after the effective 
date of this AD, whichever occurs later: Remove the two DC over-
voltage/feeder-fault test switches from the Test 2 Panel of the 
generator control unit and do all the follow-on actions specified in 
the Accomplishment Instructions of Saab Service Bulletin 340-24-023, 
Revision 02, dated November 15, 2001. Do the actions per the service 
bulletin.

Credit for Previous Issue of Service Bulletin

    (b) Accomplishment of the specified actions before the effective 
date of this AD per Saab Service Bulletin 340-24-023, Revision 01, 
dated August 24, 1995; is acceptable for compliance with the 
corresponding actions required by paragraph (a) of this AD.

Alternative Methods of Compliance

    (c) In accordance with 14 CFR 39.19, the Manager, International 
Branch, ANM-116, FAA, Transport Airplane Directorate, is authorized 
to approve alternative methods of compliance for this AD.

Incorporation by Reference

    (d) Unless otherwise provided in this AD, the actions shall be 
done in accordance with Saab Service Bulletin 340-24-023, Revision 
02, dated November 15, 2001. 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, 
Link[ouml]ping, Sweden. Copies may be inspected at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington; or at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, call (202) 741-6030, or go to: <a href="http://www.archives">http://www.archives</a>. gov/
federal-- register/code-- of--federal-- regulations/ibr-- 
locations.html.


    Note 1: The subject of this AD is addressed in Swedish 
airworthiness directive 1-169, dated November 20, 2001.

Effective Date

    (e) This amendment becomes effective on June 15, 2004.

    Issued in Renton, Washington, on April 27, 2004.
Kevin M. Mullin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-10373 Filed 5-10-04; 8:45 am]
BILLING CODE 4910-13-P

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