AD 2012-24-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Saab | Various | Airworthiness Directives; Saab AB, Saab Aerosystems Airplanes |
Unsafe Condition
Reports of stall events during icing conditions where the natural stall warning (buffet) was not identified.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Replace the stall warning computer (SWC) with a new SWC, which provides an artificial stall warning in icing conditions, and modify the airplane for the replacement of the SWC.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 12 months of the effective date (January 14, 2013).
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Saab AB, Saab Aerosystems Model 340A (SAAB/SF340A) and SAAB 340B airplanes.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
We are adopting a new airworthiness directive (AD) for certain Saab AB, Saab Aerosystems Model 340A (SAAB/SF340A) and SAAB 340B airplanes. This AD was prompted by reports of stall events during icing conditions where the natural stall warning (buffet) was not identified. This AD requires replacing the stall warning computer (SWC) with a new SWC, which provides an artificial stall warning in icing conditions, and modifying the airplane for the replacement of the SWC. We are issuing this AD to prevent natural stall events when operating in icing conditions, which, if not corrected, could result in loss of control of the airplane.
Applicability Source Text
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(c) Applicability
This AD applies to Saab AB, Saab Aerosystems Model 340A (SAAB/
SF340A) and SAAB 340B airplanes, certificated in any category, as
identified in paragraphs (c)(1) and (c)(2) of this AD, except
airplanes that have SAAB Modification 2650 and/or 2859 installed.
This AD does not apply to airplanes with serial numbers 170, 342,
362, 363, 367, 372, 379, 385, 395, 405, 409, 431, and 455.
(1) Model 340A (SAAB/SF340A) airplanes, serial numbers 004
through 159 inclusive.
(2) Model SAAB 340B airplanes, serial numbers 160 through 459
inclusive.
Document Text
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[Federal Register Volume 77, Number 237 (Monday, December 10, 2012)]
[Rules and Regulations]
[Pages 73279-73282]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2012-29169]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2012-0672; Directorate Identifier 2011-NM-261-AD;
Amendment 39-17276; AD 2012-24-06]
RIN 2120-AA64
Airworthiness Directives; Saab AB, Saab Aerosystems Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule.
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SUMMARY: We are adopting a new airworthiness directive (AD) for certain
Saab AB, Saab Aerosystems Model 340A (SAAB/SF340A) and SAAB 340B
airplanes. This AD was prompted by reports of stall events during icing
conditions where the natural stall warning (buffet) was not identified.
This AD requires replacing the stall warning computer (SWC) with a new
SWC, which provides an artificial stall
[[Page 73280]]
warning in icing conditions, and modifying the airplane for the
replacement of the SWC. We are issuing this AD to prevent natural stall
events when operating in icing conditions, which, if not corrected,
could result in loss of control of the airplane.
DATES: This AD becomes effective January 14, 2013.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of January 14,
2013.
ADDRESSES: You may examine the AD docket on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> or in person at the U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue SE., Washington, DC.
FOR FURTHER INFORMATION CONTACT: Shahram Daneshmandi, Aerospace
Engineer, International Branch, ANM-116, Transport Airplane
Directorate, FAA, 1601 Lind Avenue SW., Renton, Washington 98057-3356;
telephone (425) 227-1112; fax (425) 227-1149.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to include an AD that would apply to the specified products.
That NPRM was published in the Federal Register on June 27, 2012 (77 FR
38224). That NPRM proposed to correct an unsafe condition for the
specified products. The Mandatory Continuing Airworthiness Information
(MCAI) states:
A few natural stall events, specifically when operating in icing
conditions, have been experienced on SAAB 340 series aeroplanes,
without receiving a prior stall warning. This condition, if not
corrected, could result in loss of control of the aeroplane.
To address this potential unsafe condition, a modified stall
warning system, incorporating improved stall warning logic, has been
developed.
SAAB have issued Service Bulletin (SB) 340-27-098 and SB 340-27-
099, which include instructions to replace the present Stall Warning
Computer (SWC) with a new SWC, and instructions to activate the new
SWC. The new system includes stall warning curves optimized for
operation in icing conditions, which are activated by selection of
Engine Anti-Ice.
For the reasons described above, this [European Aviation Safety
Agency (EASA)] AD requires the replacement of the SWC, by installing
new SWC Part Number (P/N) 0020AK6 on aeroplanes with basic wing tip,
and installing a new SWC P/N 0020AK7 on aeroplanes with extended
wing tip, as applicable to aeroplane configuration.
You may obtain further information by examining the MCAI in the AD
docket.
Comments
We gave the public the opportunity to participate in developing
this AD. We considered the comments received. The National
Transportation Safety Board stated that it supports the NPRM (77 FR
38224, June 27, 2012).
Request To Revise Company Name and Email Address
Saab AB (the commenter) requested that we revise the NPRM (77 FR
38224, June 27, 2012) throughout to change the name of the Saab company
referenced in the NPRM from ``Saab AB, Saab Aerosystems'' to the new
company name, ``Saab AB, Aeronautics.'' The commenter also requested to
change the company email address referenced in the NPRM from
``<a href="/cdn-cgi/l/email-protection#dba8babab9e9ebebebafbeb8b3a8aeababb4a9af9ba8babab9bca9b4aeabf5b8b4b6"><span class="__cf_email__" data-cfemail="2c5f4d4d4e1e1c1c1c58494f445f595c5c435e586c5f4d4d4e4b5e43595c024f4341">[email protected]</span></a>'' to
``<a href="/cdn-cgi/l/email-protection#c3b0a2a2a1f0f7f3b7a6a0abb0b6b3b3acb1b783b0a2a2a1a4b1acb6b3eda0acae"><span class="__cf_email__" data-cfemail="413220202372757135242229323431312e3335013220202326332e34316f222e2c">[email protected]</span></a>.''
We agree with the intent of the commenter's request. The FAA is in
the process of changing the type certificate data sheet (TCDS) to
reflect the name change. We will use the name identified in the current
TCDS so as not to delay issuance of the final rule. Once the TCDS has
been changed, we will use the new name in subsequent ADs. We changed
the email address appropriately in paragraph (m) of this AD.
Request To Revise Text in Summary Section and Paragraph (e) of the NPRM
(77 FR 38224, June 27, 2012)
Saab AB requested that we revise the second and third sentences in
the Summary section and a related sentence in paragraph (e) of the NPRM
(77 FR 38224, June 27, 2012). In the Summary section, the commenter
requested that we revise the following text to clarify that the
airplane had been certified with natural buffet--as the stall warning--
in icing conditions, and explained that replacement of the SWC would
increase the safety level by introducing an artificial stall warning
for icing conditions.
This proposed AD was prompted by reports of stall events during
icing conditions which were not accompanied with a prior stall
warning. This proposed AD would require replacing the stall warning
computer (SWC) with a new SWC, and modifying the airplane for the
replacement of the SWC.
The commenter suggested the following text.
This proposed AD was prompted by reports of stall events during
icing conditions where the natural stall warning (buffet) was not
identified. This proposed AD would require replacing the stall
warning computer (SWC) with a new SWC, which provides an artificial
stall warning in icing conditions, and modifying the airplane for
the replacement of the SWC.
The commenter also requested that the first sentence in paragraph
(e) of the NPRM (77 FR 38224, June 27, 2012) be changed to match the
new wording.
We agree with the request for the reasons provided by the
commenter. Therefore, we changed the wording in the Summary section and
paragraph (e) of this AD as proposed by the commenter.
Request To Revise Text in Paragraph (i) of the NPRM (77 FR 38224, June
27, 2012)
Saab AB requested that we revise paragraph (i) of the NPRM (77 FR
38224, June 27, 2012), which reads ``As of effective date of this AD,
do not install any SWC having P/N 0020AK, 0020AK1, 0020AK2, 0020AK4, or
0020AK3 MOD 1 on any airplane,'' to ``After modification of an airplane
as required by paragraph (g) and (h) of this AD, do not install any SWC
having P/N 0020AK, 0020AK1, 0020AK2, 0020AK4, or 0020AK3 MOD 1 on any
airplane.'' The commenter stated that this change would allow an
operator, during the compliance time, to install an SWC having the same
part number of the failed SWC.
We agree because there is a potential problem with availability of
the new part. Therefore, we have changed the wording in paragraph (i)
of this AD to match the intent of the commenter's request.
Conclusion
We reviewed the available data, including the comments received,
and determined that air safety and the public interest require adopting
the AD with the changes described previously--except for minor
editorial changes. We have determined that these changes:
<bullet> Are consistent with the intent that was proposed in the
NPRM (77 FR 38224, June 27, 2012) for correcting the unsafe condition;
and
<bullet> Do not add any additional burden upon the public than was
already proposed in the NPRM (77 FR 38224, June 27, 2012).
Costs of Compliance
We estimate that this AD will affect 162 products of U.S. registry.
We also estimate that it will take about 78 work-hours per product to
comply with the basic requirements of this AD. The average labor rate
is $85 per work-hour. Required parts will cost about $33,000 per
product. Where the service information lists required parts costs that
are covered under warranty, we
[[Page 73281]]
have assumed that there will be no charge for these parts. As we do not
control warranty coverage for affected parties, some parties may incur
costs higher than estimated here. Based on these figures, we estimate
the cost of this AD to the U.S. operators to be $6,420,060, or $39,630
per product.
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 determined that this AD will not have federalism implications
under Executive Order 13132. This AD 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.
For the reasons discussed above, I certify that this AD:
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);
3. Will not affect intrastate aviation in Alaska; and
4. 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 AD and placed it in the AD docket.
Examining the AD Docket
You may examine the AD docket on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a>; or in person at the Docket Operations office
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains the NPRM (77 FR 38224, June 27, 2012),
the regulatory evaluation, any comments received, and other
information. The street address for the Docket Operations office
(telephone (800) 647-5527) is in the ADDRESSES section. Comments will
be available in the AD docket shortly after receipt.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 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. The FAA amends Sec. 39.13 by adding the following new AD:
2012-24-06 Saab AB, Saab Aerosystems: Amendment 39-17276. Docket No.
FAA-2012-0672; Directorate Identifier 2011-NM-261-AD.
(a) Effective Date
This airworthiness directive (AD) becomes effective January 14,
2013.
(b) Affected ADs
None.
(c) Applicability
This AD applies to Saab AB, Saab Aerosystems Model 340A (SAAB/
SF340A) and SAAB 340B airplanes, certificated in any category, as
identified in paragraphs (c)(1) and (c)(2) of this AD, except
airplanes that have SAAB Modification 2650 and/or 2859 installed.
This AD does not apply to airplanes with serial numbers 170, 342,
362, 363, 367, 372, 379, 385, 395, 405, 409, 431, and 455.
(1) Model 340A (SAAB/SF340A) airplanes, serial numbers 004
through 159 inclusive.
(2) Model SAAB 340B airplanes, serial numbers 160 through 459
inclusive.
(d) Subject
Air Transport Association (ATA) of America Code 27: Flight
Controls.
(e) Reason
This AD was prompted by reports of stall events during icing
conditions where the natural stall warning (buffet) was not
identified. We are issuing this AD to prevent natural stall events
when operating in icing conditions, which, if not corrected, could
result in loss of control of the airplane.
(f) Compliance
You are responsible for having the actions required by this AD
performed within the compliance times specified, unless the actions
have already been done.
(g) Replacement
(1) For airplanes with basic wing tips: Within 24 months after
the effective date of this AD, replace all stall warning computers
(SWCs) having part number (P/N) 0020AK, 0020AK1, 0020AK2, or
0020AK4, with a new SWC P/N 0020AK6, in accordance with the
Accomplishment Instructions of Saab Service Bulletin 340-27-098,
Revision 01, dated April 13, 2012.
(2) For airplanes with extended wing tips: Within 24 months
after the effective date of this AD, replace the SWC P/N 0020AK3 MOD
1 with a new SWC P/N 0020AK7, in accordance with the Accomplishment
Instructions of Saab Service Bulletin 340-27-099, Revision 01, dated
April 13, 2012.
(h) Concurrent Modification
Before or concurrently with the accomplishment of the
requirements of paragraph (g) of this AD: Modify the airplane in
accordance with the Accomplishment Instructions of Saab Service
Bulletin 340-27-097, Revision 03, dated April 19, 2012.
(i) Parts Installation Prohibition
After accomplishing the replacement required by paragraph (g) of
this AD and the modification required by paragraph (h) of this AD,
do not install any SWC having P/N 0020AK, 0020AK1, 0020AK2, 0020AK4,
or 0020AK3 MOD 1 on any airplane.
(j) Credit for Previous Actions
This paragraph provides credit for actions required by paragraph
(h) of this AD, if those actions were performed before the effective
date of this AD using the service bulletin specified in paragraph
(j)(1), (j)(2), or (j)(3) of this AD, which are not incorporated by
reference in this AD.
(1) Saab Service Bulletin 340-27-097, dated September 1, 2011.
(2) Saab Service Bulletin 340-27-097, Revision 01, dated
September 26, 2011.
(3) Saab Service Bulletin 340-27-097, Revision 02, dated October
7, 2011.
(k) Other FAA AD Provisions
The following provisions also apply to this AD:
(1) Alternative Methods of Compliance (AMOCs): The Manager, ANM-
116, International Branch, Transport Airplane Directorate, FAA, has
the authority to approve AMOCs for this AD, if requested using the
procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19,
send your request to your principal inspector or local Flight
Standards District Office, as appropriate. If sending information
directly to the International Branch, send it to ATTN: Shahram
Daneshmandi, Aerospace Engineer, International Branch, ANM-116,
Transport Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton,
Washington 98057-3356; telephone (425) 227-1112; fax (425) 227-1149.
Information may be emailed to: <a href="/cdn-cgi/l/email-protection#ad9480ece3e0809c9c9b80ece0e2ee80ffe8fcf8e8fef9feedcbcccc83cac2db"><span class="__cf_email__" data-cfemail="1a23375b5457372b2b2c375b57555937485f4b4f5f494e495a7c7b7b347d756c">[email protected]</span></a>.
Before using any approved AMOC, notify your appropriate principal
inspector, or lacking a principal inspector, the manager of the
local flight standards district office/
[[Page 73282]]
certificate holding district office. The AMOC approval letter must
specifically reference this AD.
(2) Airworthy Product: For any requirement in this AD to obtain
corrective actions from a manufacturer or other source, use these
actions if they are FAA-approved. Corrective actions are considered
FAA-approved if they are approved by the State of Design Authority
(or their delegated agent). You are required to assure the product
is airworthy before it is returned to service.
(l) Related Information
Refer to MCAI European Aviation Safety Agency Airworthiness
Directive 2011-0219, dated November 11, 2011, and the service
information specified in paragraphs (l)(1) through (l)(3) of this
AD, for related information.
(1) Saab Service Bulletin 340-27-097, Revision 03, dated April
19, 2012.
(2) Saab Service Bulletin 340-27-098, Revision 01, dated April
13, 2012.
(3) Saab Service Bulletin 340-27-099, Revision 01, dated April
13, 2012.
(m) Material Incorporated by Reference
(1) The Director of the Federal Register approved the
incorporation by reference (IBR) of the service information listed
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) You must use this service information as applicable to do
the actions required by this AD, unless the AD specifies otherwise.
(i) Saab Service Bulletin 340-27-097, Revision 03, dated April
19, 2012.
(ii) Saab Service Bulletin 340-27-098, Revision 01, dated April
13, 2012.
(iii) Saab Service Bulletin 340-27-099, Revision 01, dated April
13, 2012.
(3) For service information identified in this AD, contact Saab
AB, Saab Aeronautics, SE-581 88, Link[ouml]ping, Sweden; telephone
+46 13 18 5591; fax +46 13 18 4874; email
<a href="/cdn-cgi/l/email-protection#89fae8e8ebbabdb9fdeceae1fafcf9f9e6fbfdc9fae8e8ebeefbe6fcf9a7eae6e4"><span class="__cf_email__" data-cfemail="0f7c6e6e6d3c3b3f7b6a6c677c7a7f7f607d7b4f7c6e6e6d687d607a7f216c6062">[email protected]</span></a>; Internet <a href="http://www.saabgroup.com">http://www.saabgroup.com</a>.
(4) You may review copies of the service information at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, WA.
For information on the availability of this material at the FAA,
call 425-227-1221.
(5) You may view this service information that is incorporated
by reference 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.gov/federal-register/cfr/ibr-locations.html">http://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.
Issued in Renton, Washington, on November 21, 2012.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2012-29169 Filed 12-7-12; 8:45 am]
BILLING CODE 4910-13-P
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