[Federal Register Volume 71, Number 129 (Thursday, July 6, 2006)]
[Proposed Rules]
[Pages 38311-38313]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-10537]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-25271; Directorate Identifier 2006-NM-067-AD]
RIN 2120-AA64


Airworthiness Directives; Saab Model SAAB-Fairchild SF340A (SAAB/
SF340A) and SAAB 340B Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede an existing airworthiness 
directive (AD) that applies to certain Model SAAB-Fairchild SF340A and 
SAAB 340B airplanes. The existing AD currently requires repetitive 
inspections for wear of the brushes and leads and for loose rivets of 
the direct current (DC) starter generator, and related investigative/
corrective actions if necessary. This proposed AD would require 
installing new improved generator control units (GCUs). Installing the 
GCUs would end the repetitive inspection requirements of the existing 
AD. This proposed AD results from reports of premature failures of the 
DC starter generator prior to scheduled overhaul. We are proposing this 
AD to prevent failure of the starter generator, which could cause a low 
voltage situation in flight and result in increased pilot workload and 
reduced redundancy of the electrical powered systems.

DATES: We must receive comments on this proposed AD by August 7, 2006.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD.
     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590.
     Fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    Contact Saab Aircraft AB, SAAB Aircraft Product Support, S-581.88, 
Linkoping, Sweden, for service information identified in this proposed 
AD.

FOR FURTHER INFORMATION CONTACT: Mike Borfitz, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2677; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to submit any relevant written data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed in the ADDRESSES section. Include the docket number ``Docket No. 
FAA-2006-25271; Directorate Identifier 2006-NM-067-AD'' at the 
beginning of your comments. We specifically invite comments on the 
overall regulatory, economic, environmental, and energy aspects of the 
proposed AD. We will consider all comments received by the closing date 
and may amend the proposed AD in light of those comments.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this proposed AD. Using the search function of 
that Web site, anyone can find and read the comments in any of our 
dockets, including the name of the individual who sent the comment (or 
signed the comment on behalf of an association, business, labor union, 
etc.). You may review the DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78), or you 
may visit http://dms.dot.gov.

Examining the Docket

    You may examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Management Facility office (telephone (800) 647-
5227) is located on the plaza level of the Nassif Building at the DOT 
street address stated in the ADDRESSES section. Comments will be 
available in the AD docket shortly after the Docket Management System 
receives them.

Discussion

    On February 11, 2005, we issued AD 2005-04-12, amendment 39-13984 
(70 FR 9215, February 25, 2005), for certain Saab Model SAAB SF340A and 
SAAB 340B series airplanes. That AD requires repetitive inspections for 
wear of the brushes and leads and for loose rivets of the direct 
current (DC) starter generator, and related investigative/corrective 
actions if necessary. That AD resulted from reports of premature 
failures of the DC starter generator prior to scheduled overhaul. We 
issued that AD to prevent failure of the starter generator, which could 
cause a low voltage situation in flight and result in increased pilot 
workload and reduced redundancy of the electrical powered systems.

Actions Since Existing AD Was Issued

    The preamble to AD 2005-04-12 explains that we considered the 
requirements ``interim action'' and were considering further rulemaking 
if a final action is identified. The manufacturer has now designed a 
new improved generator control unit (GCU), and we have determined that 
further rulemaking is indeed necessary; this proposed AD follows from 
that determination.

Relevant Service Information

    Saab has issued Saab 340 Service Bulletin 340-24-026, Revision 03, 
dated December 20, 2004. The service bulletin describes procedures for 
installing new improved GCUs. Accomplishing the actions specified in 
the service information is intended to adequately address the unsafe 
condition. The Luftfartsverket (LFS), which is the airworthiness 
authority for Sweden, mandated the service information and issued 
Swedish airworthiness directive 1-197, dated November 5, 2004, to 
ensure the continued airworthiness of these airplanes in Sweden.

[[Page 38312]]

FAA's Determination and Requirements of the Proposed AD

    These airplane models are manufactured in Sweden and are 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 LFS has kept the FAA informed of 
the situation described above. We have examined the LFS's findings, 
evaluated all pertinent information, and determined that AD action is 
necessary for airplanes of this type design that are certificated for 
operation in the United States. This proposed AD would supersede AD 
2005-04-12 and would continue to require repetitive inspections for 
wear of the brushes and leads and for loose rivets of the direct 
current (DC) starter generator, and related investigative/corrective 
actions if necessary. This proposed AD would also require installing 
new improved GCUs. Installing the GCUs would end the repetitive 
inspection requirements of AD 2005-04-12.

Changes to Existing AD

    This proposed AD would retain all requirements of AD 2005-04-12. 
Since AD 2005-04-12 was issued, the AD format has been revised, and 
certain paragraphs have been rearranged. As a result, the corresponding 
paragraph identifiers have changed in this proposed AD, as listed in 
the following table:

                      Revised Paragraph Identifiers
------------------------------------------------------------------------
                                             Corresponding  requirement
       Requirement in AD 2005-04-12             in this  proposed AD
------------------------------------------------------------------------
paragraph (e).............................  paragraph (f).
paragraph (f).............................  paragraph (g).
paragraph (g).............................  paragraph (h).
------------------------------------------------------------------------

    We have revised the applicability to identify model designations as 
published in the most recent type certificate data sheet for the 
affected models.
    We have also revised this action to clarify the appropriate 
procedure for notifying the principal inspector before using any 
approved AMOC on any airplane to which the AMOC applies.
    For clarification, we have revised the definition of a ``general 
visual inspection'' in Note 1 of this proposed AD.

Explanation of Change to Costs of Compliance

    After AD 2005-04-12 was issued, we reviewed the figures we have 
used over the past several years to calculate AD costs to operators. To 
account for various inflationary costs in the airline industry, we find 
it necessary to increase the labor rate used in these calculations from 
$65 per work hour to $80 per work hour. The cost impact information, 
below, reflects this increase in the specified hourly labor rate.

Costs of Compliance

    This proposed AD would affect about 170 airplanes of U.S. registry. 
The following table provides the estimated costs for U.S. operators to 
comply with this proposed AD.

                                                 Estimated Costs
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                                                 Average
             Action                Work hours   labor rate     Parts      Cost per airplane       Fleet cost
                                                 per hour
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Inspections (required by AD 2005-           1          $80           $0  $80, per inspection  $13,600, per
 04-02).                                                                  cycle.               inspection cycle.
Installation (new proposed                  1           80        7,598  7,678..............  $1,305,260.
 action).
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Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, Section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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.
    For the reasons discussed above, I certify that the proposed 
regulation:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866;
    2. Is not a ``significant rule'' under the 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD and placed it in the AD docket. See the 
ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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. The Federal Aviation Administration (FAA) amends Sec.  39.13 by 
removing amendment 39-13984 (70 FR 9215, February 25, 2005) and adding 
the following new airworthiness directive (AD):


[[Page 38313]]


SAAB Aircraft AB: Docket No. FAA-2006-25271; Directorate Identifier 
2006-NM-067-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by August 7, 
2006.

Affected ADs

    (b) This AD supersedes AD 2005-04-12.

Applicability

    (c) This AD applies to Saab Model SAAB-Fairchild SF340A (SAAB/
SF340A) airplanes having serial numbers 004 through 159 inclusive, 
and Model SAAB 340B airplanes having serial numbers 160 through 367 
inclusive; certificated in any category; on which Saab Modification 
2533 has not been implemented.

Unsafe Condition

    (d) This AD results from reports of premature failures of the 
direct current (DC) starter generator prior to scheduled overhaul. 
We are issuing this AD to prevent failure of the starter generator, 
which could cause a low voltage situation in flight and result in 
increased pilot workload and reduced redundancy of the electrical 
powered systems.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Restatement of the Requirements of AD 2005-04-12

Inspections for Wear of the DC Starter Generator Brushes and Leads

    (f) For generators overhauled in accordance with Maintenance 
Review Board (MRB) Task 243104: Before 800 flight hours since last 
overhaul, or within 100 flight hours after April 1, 2005 (the 
effective date of AD 2005-04-12), perform a general visual 
inspection for wear of the DC starter generator brushes and leads, 
in accordance with Saab Service Bulletin 340-24-035, dated July 5, 
2004.

    Note 1: For the purposes of this AD, a general visual inspection 
is: ``A visual examination of an interior or exterior area, 
installation, or assembly to detect obvious damage, failure, or 
irregularity. This level of inspection is made from within touching 
distance unless otherwise specified. A mirror may be necessary to 
ensure visual access to all surfaces in the inspection area. This 
level of inspection is made under normally available lighting 
conditions such as daylight, hangar lighting, flashlight, or 
droplight and may require removal or opening of access panels or 
doors. Stands, ladders, or platforms may be required to gain 
proximity to the area being checked.''


    Note 2: Saab Service Bulletin 340-24-035, dated July 5, 2004, 
references Goodrich Service Information Letter 23080-03X-24-01, 
dated July 1, 2004, as an additional source of service information.

    (1) If the tops of the brush sets are above the top of the brush 
box, repeat the inspection thereafter at intervals not to exceed 800 
flight hours until paragraph (i) of this AD is done.
    (2) If the tops of the brush sets are below the top of the brush 
box, before further flight, measure the brushes and determine the 
remaining amount of brush life remaining, in accordance with the 
service bulletin.
    (i) If the brush wear is within the limits specified in the 
service bulletin, repeat the inspection thereafter at intervals not 
to exceed 800 flight hours until paragraph (i) of this AD is done.
    (ii) If the brush wear is outside the limits specified in the 
service bulletin, before further flight, replace the starter 
generator with a new or serviceable starter generator, in accordance 
with the service bulletin.

Inspections for Loose Rivets

    (g) For generators overhauled in accordance with MRB Task 
243104: Before 800 flight hours since last overhaul, or within 100 
flight hours after April 1, 2005, whichever occurs later, perform a 
general visual inspection of each leading wafer brush for loose 
rivets, in accordance with Saab Service Bulletin 340-24-035, dated 
July 5, 2004. Repeat the inspection thereafter at intervals not to 
exceed 800 flight hours until paragraph (i) of this AD is done. If 
any rivet is loose, before further flight, replace the DC starter 
generator with a new or serviceable starter generator, in accordance 
with the service bulletin.

MRB Task 243103 or 243101

    (h) For generators overhauled or with brush replacement 
accomplished in accordance with MRB Task 243103 or 243101, no action 
is required by paragraphs (f) and (g) of this AD.

New Requirements of This AD

Installation

    (i) For all generators: Within 36 months after the effective 
date of this AD, install new improved generator control units (GCUs) 
in accordance with the Accomplishment Instructions of Saab Service 
Bulletin 340-24-026, Revision 03, dated December 20, 2004. 
Installing the GCUs terminates the repetitive inspection 
requirements of paragraphs (f) and (g) of this AD.

Alternative Methods of Compliance (AMOCs)

    (j)(1) The Manager, International Branch, ANM-116, Transport 
Airplane Directorate, FAA, has the authority to approve AMOCs for 
this AD, if requested in accordance with the procedures found in 14 
CFR 39.19.
    (2) Before using any AMOC approved in accordance with Sec.  
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.

Related Information

    (k) Swedish airworthiness directive 1-197, dated November 5, 
2004, also addresses the subject of this AD.

    Issued in Renton, Washington, on June 28, 2006.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E6-10537 Filed 7-5-06; 8:45 am]
BILLING CODE 4910-13-P