AD 2016-22-15
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Saab AB, Saab Aeronautics | 340A (SAAB SF340A) | Airworthiness Directives; Saab AB, Saab Aeronautics (Formerly Known as Saab AB, Saab Aerosystems) Airplanes |
| aircraft | Saab AB, Saab Aeronautics | SAAB 340B | Airworthiness Directives; Saab AB, Saab Aeronautics (Formerly Known as Saab AB, Saab Aerosystems) Airplanes |
Unsafe Condition
Natural stall events during operation in icing conditions without prior stall warning, which could result in loss of control of the airplane.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Replace the existing stall warning computer (SWC) with a new, improved SWC that provides an artificial stall warning in icing conditions. Modify the airplane for the replacement of the SWC. Deactivate the ice speed curves in the improved SWC as per applicable service bulletins.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 12 months of the effective date of this AD.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Saab AB, Saab Aeronautics Model 340A (SAAB/SF340A) and SAAB 340B airplanes, including those with certain modifications that were previously excluded from AD 2012-24-06.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
We are superseding Airworthiness Directive (AD) 2012-24-06 for certain Saab AB, Saab Aeronautics Model 340A (SAAB/SF340A) and SAAB 340B airplanes. AD 2012-24-06 required replacing the stall warning computer (SWC) with a new SWC that provides an artificial stall warning in icing conditions, and modifying the airplane for the replacement of the SWC. This new AD adds airplanes to the applicability, and adds requirements to replace the existing SWCs with new, improved SWCs, and to modify the airplane for the new replacement of the SWC. This new AD also reduces the compliance time for replacing the SWCs. This AD was prompted by a determination that airplanes with certain modifications were excluded from the applicability in AD 2012-24-06, and are affected by the identified unsafe condition; and that the SWC required by AD 2012-24-06 contained erroneous logic. We are issuing this AD to prevent natural stall events during operation in icing conditions, which could result in loss of control of the airplane.
Applicability Source Text
Show captured applicability text from the source AD
(c) Applicability
This AD applies to Saab AB, Saab Aeronautics (formerly known as
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.
(1) Model 340A (SAAB/SF340A) airplanes, serial numbers 004
through 159 inclusive.
(2) Model SAAB 340B airplanes, serial numbers 160 through 459
inclusive, except serial numbers 170, 342, 362, 363, 367, 372, 379,
385, 395, 405, 409, 431, 441, and 455.
[[Page 76845]]
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 81, Number 214 (Friday, November 4, 2016)]
[Rules and Regulations]
[Pages 76843-76845]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2016-26327]
========================================================================
Rules and Regulations
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains regulatory documents
having general applicability and legal effect, most of which are keyed
to and codified in the Code of Federal Regulations, which is published
under 50 titles pursuant to 44 U.S.C. 1510.
The Code of Federal Regulations is sold by the Superintendent of Documents.
Prices of new books are listed in the first FEDERAL REGISTER issue of each
week.
========================================================================
Federal Register / Vol. 81, No. 214 / Friday, November 4, 2016 /
Rules and Regulations
[[Page 76843]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2015-6544; Directorate Identifier 2014-NM-198-AD;
Amendment 39-18704; AD 2016-22-15]
RIN 2120-AA64
Airworthiness Directives; Saab AB, Saab Aeronautics (Formerly
Known as Saab AB, Saab Aerosystems) Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: We are superseding Airworthiness Directive (AD) 2012-24-06 for
certain Saab AB, Saab Aeronautics Model 340A (SAAB/SF340A) and SAAB
340B airplanes. AD 2012-24-06 required replacing the stall warning
computer (SWC) with a new SWC that provides an artificial stall warning
in icing conditions, and modifying the airplane for the replacement of
the SWC. This new AD adds airplanes to the applicability, and adds
requirements to replace the existing SWCs with new, improved SWCs, and
to modify the airplane for the new replacement of the SWC. This new AD
also reduces the compliance time for replacing the SWCs. This AD was
prompted by a determination that airplanes with certain modifications
were excluded from the applicability in AD 2012-24-06, and are affected
by the identified unsafe condition; and that the SWC required by AD
2012-24-06 contained erroneous logic. We are issuing this AD to prevent
natural stall events during operation in icing conditions, which could
result in loss of control of the airplane.
DATES: This AD is effective December 9, 2016.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of December 9,
2016.
ADDRESSES: For service information identified in this final rule,
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#c7b4a6a6a5f4f3f7e9b3a2a4afb4b2b7b7a8b5b387b4a6a6a5a0b5a8b2b7e9a4a8aa"><span class="__cf_email__" data-cfemail="7d0e1c1c1f4e494d5309181e150e080d0d120f093d0e1c1c1f1a0f12080d531e1210">[email protected]</span></a>; Internet <a href="http://www.saabgroup.com">http://www.saabgroup.com</a>.
You may view this referenced 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. It
is also available on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by
searching for and locating Docket No. FAA-2015-6544.
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> by searching for and locating Docket No. FAA-2015-
6544; or in person at the Docket Management Facility between 9 a.m. and
5 p.m., Monday through Friday, except Federal holidays. The AD docket
contains this AD, the regulatory evaluation, any comments received, and
other information. The address for the Docket Office (telephone 800-
647-5527) is Docket Management Facility, U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Shahram Daneshmandi, Aerospace
Engineer, International Branch, ANM-116, Transport Airplane
Directorate, FAA, 1601 Lind Avenue SW., Renton, WA 98057-3356;
telephone 425-227-1112; fax 425-227-1149.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a supplemental notice of proposed rulemaking (SNPRM) to
amend 14 CFR part 39 to supersede AD 2012-24-06, Amendment 39-17276 (77
FR 73279, December 10, 2012) (``AD 2012-24-06''). AD 2012-24-06 applied
to certain Saab AB, Saab Aeronautics Model 340A (SAAB/SF340A) and SAAB
340B airplanes. The SNPRM published in the Federal Register on July 12,
2016 (81 FR 45072) (``the SNPRM''). We preceded the SNPRM with a notice
of proposed rulemaking (NPRM) that published in the Federal Register on
December 17, 2015 (80 FR 78699) (``the NPRM''). The NPRM was prompted
by a determination that airplanes with certain modifications were
excluded from the applicability in AD 2012-24-06, and are affected by
the identified unsafe condition; and the SWC required by AD 2012-24-06
contained erroneous logic. The NPRM proposed to add airplanes to the
applicability and to add requirements to replace the existing SWCs with
new, improved SWCs and to modify the airplane for the new replacement
of the SWC. The SNPRM proposed to reduce the compliance time for
replacing the SWCs. We are issuing this AD to prevent natural stall
events during operation in icing conditions, which could result in loss
of control of the airplane.
The European Aviation Safety Agency (EASA), which is the Technical
Agent for the Member States of the European Union, has issued EASA
Airworthiness Directive 2014-0218, dated September 29, 2014 (referred
to after this as the Mandatory Continuing Airworthiness Information, or
``the MCAI''), to correct an unsafe condition on certain Saab AB, Saab
Aeronautics Model 340A (SAAB/SF340A) and SAAB 340B airplanes. The 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, SAAB developed a
modified stall warning system, incorporating improved stall warning
logic, and issued Service Bulletin (SB) 340-27-098 and SB 340-27-
099, providing instructions to replace the Stall Warning Computer
(SWC) with a new SWC, and instructions to activate the new SWC. The
new system included stall warning curves optimized for operation in
icing conditions, which are activated by selection of Engine Anti-
Ice.
Consequently, EASA issued AD 2011-0219 to require installation
of the improved SWC.
After that [EASA] AD was issued, in-service experience with the
improved stall warning system revealed cases of premature stall
warning activation during the take-off phase. In numerous recorded
cases, the onset of stall warning occurred without the 6 minute
delay after weight off wheels.
[[Page 76844]]
This condition, if not corrected, could lead to premature stick
shaker activation and consequent increase in pilot workload during
the take-off phase, possibly resulting in reduced control of the
aeroplane.
To correct this unsafe condition, EASA issued AD 2013-0254
retaining the requirements of EASA AD 2011-0219, which was
superseded, to require deactivation of the ice speed curves in the
improved SWC on SAAB 340 aeroplanes, in accordance with SAAB SB 340-
27-116.
Since EASA AD 2013-0254 was issued, SAAB developed a technical
solution to eliminate the premature activation of the stall warning
ice curves and issued SB 340-27-120 (modification of the existing
Stall Warning System installation), SB 340-27-121 (activation of
improved SWC for aeroplanes with a basic wing tip) and SB 340-27-122
(activation of improved SWC for aeroplanes with an extended wing
tip). SAAB SB 340-27-120 provides modification and installation
instructions valid for pre- and post-SB 340-27-097, 340-27-098, SB
340-27-099 and SB 340-27-116 aeroplanes. For aeroplanes modified in
accordance with SAAB AB mod. No. 2650 and/or mod. No. 2859 which are
no longer registered in Canada, SAAB AB issued SAAB AB SB 340-27-109
to provide modification and installation instructions to remove the
ice speed curve function.
For the reasons described above, this [EASA] AD retains the
requirements of EASA AD 2013-0254, which is superseded, and requires
modification of the Stall Warning and Identification System and
replacement of the SWC with an improved unit.
You may examine the MCAI in the AD docket on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by searching for and locating Docket No. FAA-2015-
6544.
Comments
We gave the public the opportunity to participate in developing
this AD. We received no comments on the SNPRM or on the determination
of the cost to the public.
Conclusion
We reviewed the available data and determined that air safety and
the public interest require adopting this AD as proposed, except for
minor editorial changes. We have determined that these minor changes:
<bullet> Are consistent with the intent that was proposed in the
SNPRM for correcting the unsafe condition; and
<bullet> Do not add any additional burden upon the public than was
already proposed in the SNPRM.
Related Service Information Under 1 CFR Part 51
Saab AB, Saab Aeronautics has issued the following service
information:
<bullet> Saab Service Bulletin 340-27-109, dated April 14, 2014.
<bullet> Saab Service Bulletin 340-27-116, dated October 18, 2013.
<bullet> Saab Service Bulletin 340-27-120, dated July 11, 2014.
<bullet> Saab Service Bulletin 340-27-121, dated July 11, 2014.
<bullet> Saab Service Bulletin 340-27-122, dated July 11, 2014.
The service information describes procedures for deactivating the
stall warning speed curves in the SWCs for certain airplanes; replacing
the existing SWCs with new, improved SWCs; and modifying the airplane
for the new replacement of the SWC. These documents are distinct since
they apply to different airplane models in different configurations.
This service information is reasonably available because the interested
parties have access to it through their normal course of business or by
the means identified in the ADDRESSES section.
Costs of Compliance
We estimate that this AD affects 105 airplanes of U.S. registry.
The actions required by AD 2012-24-06 and retained in this AD, take
about 78 work-hours per product, at an average labor rate of $85 per
work-hour. Required parts cost about $33,000 per product. Based on
these figures, the estimated cost of the actions that were required by
AD 2012-24-06 is $39,630 per product.
The new requirement of this AD adds no additional economic burden.
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.
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 removing Airworthiness Directive (AD)
2012-24-06, Amendment 39-17276 (77 FR 73279, December 10, 2012), and
adding the following new AD:
2016-22-15 Saab AB, Saab Aeronautics: Amendment 39-18704; Docket No.
FAA-2015-6544; Directorate Identifier 2014-NM-198-AD.
(a) Effective Date
This AD is effective December 9, 2016.
(b) Affected ADs
This AD replaces AD 2012-24-06, Amendment 39-17276 (77 FR 73279,
December 10, 2012) (``AD 2012-24-06'').
(c) Applicability
This AD applies to Saab AB, Saab Aeronautics (formerly known as
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.
(1) Model 340A (SAAB/SF340A) airplanes, serial numbers 004
through 159 inclusive.
(2) Model SAAB 340B airplanes, serial numbers 160 through 459
inclusive, except serial numbers 170, 342, 362, 363, 367, 372, 379,
385, 395, 405, 409, 431, 441, and 455.
[[Page 76845]]
(d) Subject
Air Transport Association (ATA) of America Code 27, Flight
Controls.
(e) Reason
This AD was prompted by a determination that airplanes with
certain modifications were excluded from the applicability in AD
2012-24-06, and are affected by the identified unsafe condition; and
the stall warning computer (SWC) required by AD 2012-24-06 contained
erroneous logic. We are issuing this AD to prevent natural stall
events during operation in icing conditions, which could result in
loss of control of the airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Deactivation of Stall Speed Curves
For airplanes identified in paragraphs (g)(1) and (g)(2) of this
AD: Within 30 days after the effective date of this AD, do the
deactivation specified in paragraph (g)(1) or (g)(2) of this AD, as
applicable to airplane configuration, in accordance with the
Accomplishment Instructions of Saab Service Bulletin 340-27-116,
dated October 18, 2013.
(1) For airplanes with a basic wing tip that has been modified
using Saab Service Bulletin 340-27-098: Deactivate the stall speed
curves in the SWC having part number (P/N) 0020AK6.
(2) For airplanes with an extended wing tip that has been
modified using Saab Service Bulletin 340-27-099: Deactivate the
stall speed curves in the SWC having P/N 0020AK7.
(h) Replacement of SWCs
Within 3 months after the effective date of this AD: Do the
replacement specified in paragraph (h)(1) or (h)(2) of this AD, as
applicable.
(1) For airplanes with basic wing tips: Replace all SWCs with
new, improved SWCs having P/N 0020AK6-1, in accordance with the
Accomplishment Instructions of Saab Service Bulletin 340-27-121,
dated July 11, 2014.
(2) For airplanes with extended wing tips: Replace all SWCs with
new, improved SWCs having P/N 0020AK7-1, in accordance with the
Accomplishment Instructions of Saab Service Bulletin 340-27-122,
dated July 11, 2014.
(i) Concurrent Modification
Before or concurrently with the accomplishment of the applicable
requirements of paragraph (h) of this AD, do the actions specified
in paragraph (i)(1) or (i)(2) of this AD, as applicable to airplane
configuration.
(1) For airplanes on which either Saab AB Modification 2650 or
Modification 2859 is not installed: Modify the stall warning and
identification system, in accordance with the Accomplishment
Instructions of Saab Service Bulletin 340-27-120, dated July 11,
2014.
(2) For airplanes on which either Saab AB Modification 2650 or
Modification 2859 is installed, or on which both modifications are
installed: Modify the stall warning and identification system, in
accordance with the Accomplishment Instructions of Saab Service
Bulletin 340-27-109, dated April 14, 2014.
(j) Parts Installation Prohibitions
After the replacement required by paragraph (h) of this AD, no
person may install any SWC having P/N 0020AK, 0020AK1, 0020AK2,
0020AK4, 0020AK6, 0020AK7, or 0020AK3 MOD 1, on any airplane.
(k) Other FAA AD Provisions
The following provisions also apply to this AD:
(1) Alternative Methods of Compliance (AMOCs): The Manager,
International Branch, ANM-116, 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,
WA 98057-3356; telephone 425-227-1112; fax 425-227-1149. Information
may be emailed to: <a href="/cdn-cgi/l/email-protection#85bca8c4cbc8a8b4b4b3a8c4c8cac6a8d7c0d4d0c0d6d1d6c5e3e4e4abe2eaf3"><span class="__cf_email__" data-cfemail="a1988ce0efec8c9090978ce0eceee28cf3e4f0f4e4f2f5f2e1c7c0c08fc6ced7">[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/certificate holding district office. The
AMOC approval letter must specifically reference this AD.
(2) Contacting the Manufacturer: For any requirement in this AD
to obtain corrective actions from a manufacturer, the action must be
accomplished using a method approved by the Manager, International
Branch, ANM-116, Transport Airplane Directorate, FAA; or the
European Aviation Safety Agency (EASA); or Saab AB, Saab
Aeronautics' EASA Design Organization Approval (DOA). If approved by
the DOA, the approval must include the DOA-authorized signature.
(l) Related Information
Refer to Mandatory Continuing Airworthiness Information (MCAI)
EASA Airworthiness Directive 2014-0218, dated September 29, 2014,
for related information. This MCAI may be found in the AD docket on
the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by searching for and
locating Docket No. FAA-2015-6544.
(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 this AD specifies otherwise.
(i) Saab Service Bulletin 340-27-109, dated April 14, 2014.
(ii) Saab Service Bulletin 340-27-116, dated October 18, 2013.
(iii) Saab Service Bulletin 340-27-120, dated July 11, 2014.
(iv) Saab Service Bulletin 340-27-121, dated July 11, 2014.
(v) Saab Service Bulletin 340-27-122, dated July 11, 2014.
(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#5625373734656266782233353e25232626392422162537373431243923267835393b"><span class="__cf_email__" data-cfemail="6d1e0c0c0f5e595d4319080e051e181d1d021f192d1e0c0c0f0a1f02181d430e0200">[email protected]</span></a>; Internet <a href="http://www.saabgroup.com">http://www.saabgroup.com</a>.
(4) You may view this 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 October 25, 2016.
Dionne Palermo,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2016-26327 Filed 11-3-16; 8:45 am]
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