AD 2009-25-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Twin Commander Aircraft LLC | 690 | Airworthiness Directives; Twin Commander Aircraft LLC Models 690, 690A, and 690B Airplanes |
| aircraft | Twin Commander Aircraft LLC | 690A | Airworthiness Directives; Twin Commander Aircraft LLC Models 690, 690A, and 690B Airplanes |
| aircraft | Twin Commander Aircraft LLC | 690B | Airworthiness Directives; Twin Commander Aircraft LLC Models 690, 690A, and 690B Airplanes |
Unsafe Condition
Corrosion between the mating surfaces of the wing upper skin surface and the engine mount beam support straps could result in failure of the engine mount beam support straps, leading to loss of the engine and possible loss of control of the airplane.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect between the surface of the LH and RH upper wing skins and the engine mount beam support straps for any signs of corrosion. Replace the upper steel straps with parts of improved design. Modify both wings according to specified options.
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
Twin Commander Aircraft LLC Models 690, 690A, and 690B 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 Twin Commander Aircraft LLC Models 690, 690A, and 690B airplanes. This AD requires you to inspect between the surface of the left-hand (LH) and right- hand (RH) upper wing skins and the engine mount beam support straps for any signs of corrosion, replace the upper steel straps with parts of improved design, and modify both wings. This AD results from reports that corrosion was found between the mating surfaces of the wing upper skin surface and the engine mount beam support straps. We are issuing this AD to detect and correct corrosion on the engine mount beam support straps and the upper wing skins, which could result in failure of the engine mount beam support straps. This failure could lead to loss of the engine and possible loss of control of the airplane.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 74, Number 232 (Friday, December 4, 2009)]
[Rules and Regulations]
[Pages 63565-63568]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: E9-28548]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2009-0778; Directorate Identifier 2009-CE-040-AD;
Amendment 39-16119; AD 2009-25-02]
RIN 2120-AA64
Airworthiness Directives; Twin Commander Aircraft LLC Models 690,
690A, and 690B Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: We are adopting a new airworthiness directive (AD) for certain
Twin Commander Aircraft LLC Models 690, 690A, and 690B airplanes. This
AD requires you to inspect between the surface of the left-hand (LH)
and right-
[[Page 63566]]
hand (RH) upper wing skins and the engine mount beam support straps for
any signs of corrosion, replace the upper steel straps with parts of
improved design, and modify both wings. This AD results from reports
that corrosion was found between the mating surfaces of the wing upper
skin surface and the engine mount beam support straps. We are issuing
this AD to detect and correct corrosion on the engine mount beam
support straps and the upper wing skins, which could result in failure
of the engine mount beam support straps. This failure could lead to
loss of the engine and possible loss of control of the airplane.
DATES: This AD becomes effective on January 8, 2010.
On January 8, 2010, the Director of the Federal Register approved
the incorporation by reference of certain publications listed in this
AD.
ADDRESSES: To get the service information identified in this AD,
contact Twin Commander Aircraft LLC, 18933-59th Avenue, NE., Suite 115,
Arlington, WA 98223, telephone: (360) 435-9797; fax: (360) 435-1112;
Internet: <a href="http://www.twincommander.com">http://www.twincommander.com</a>.
To view the AD docket, go to U.S. Department of Transportation,
Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200
New Jersey Avenue, SE., Washington, DC 20590, or on the Internet at
<a href="http://www.regulations.gov">http://www.regulations.gov</a>. The docket number is FAA-2009-0778;
Directorate Identifier 2009-CE-040-AD.
FOR FURTHER INFORMATION CONTACT: Vince Massey, Aerospace Engineer, FAA,
Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton,
Washington 98057-3356; telephone: (425) 917-6475; fax: (425) 917-6590;
e-mail: <a href="/cdn-cgi/l/email-protection#f2849b9c9197dc9f938181978bb2949393dc959d84"><span class="__cf_email__" data-cfemail="9fe9f6f1fcfab1f2feececfae6dff9fefeb1f8f0e9">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
On August 21, 2009, we issued a proposal to amend part 39 of the
Federal Aviation Regulations (14 CFR part 39) to include an AD that
would apply to certain Twin Commander Aircraft LLC Models 690, 690A,
and 690B airplanes. This proposal was published in the Federal Register
as a notice of proposed rulemaking (NPRM) on August 28, 2009 (74 FR
44308). The NPRM proposed to require you to inspect between the surface
of the LH and RH upper wing skins and the engine mount beam support
straps for any signs of corrosion, replace the upper steel straps with
parts of improved design, and modify both wings.
Comments
We provided the public the opportunity to participate in developing
this AD. The following presents the comments received on the proposal
and FAA's response to each comment:
Comment Issue: Extend Compliance Time
Michael Curtis Pidek, William I. Smith, and Tom Bayer all state
that with 275 airplanes affected by this AD and only 15 service centers
available to do the actions required in this AD, there is not enough
time to comply with the AD.
All three commenters request an extension of the compliance time to
allow enough time for the service centers to schedule the work without
grounding airplanes until the work can be done.
We do not agree with the commenters. Over 65 airplanes are already
in compliance with this AD. We have consulted with Twin Commander
Aircraft LLC and they have covered this issue with the service centers.
The service centers know how much work is required since they have
already done the work on over 65 of the affected airplanes. The service
centers plan on using multiple teams to work on several airplanes at
the same time. They have confirmed they can perform the actions
required in this AD in the compliance time as proposed.
Part of the alternative method of compliance (AMOC) provisions of
14 CFR 39.19 is an extension of the compliance time provided a level of
safety acceptable to the FAA is met. The FAA will review any AMOCs of
this nature on a case-by-case basis. If we determine the proposal
presents an acceptable level of safety, we will approve it as an AMOC
to the AD.
We are not changing the final rule AD action based on these
comments.
Conclusion
We have carefully reviewed the available data and determined that
air safety and the public interest require adopting the AD as proposed
except for minor editorial corrections. We have determined that these
minor corrections:
<bullet> Are consistent with the intent that was proposed in the
NPRM for correcting the unsafe condition; and
<bullet> Do not add any additional burden upon the public than was
already proposed in the NPRM.
Costs of Compliance
We estimate that this AD will affect 275 airplanes in the U.S.
registry.
We estimate the following costs to do the inspection:
----------------------------------------------------------------------------------------------------------------
Total cost per Total cost on
Labor cost Parts cost airplane U.S. operators
----------------------------------------------------------------------------------------------------------------
80 work-hours x $80 per hour = $6,400........ Not applicable................. $6,400 $1,760,000
----------------------------------------------------------------------------------------------------------------
We estimate the following costs to do any necessary repairs/
replacements that will be required based on the results of the
inspection. We have no way of determining the number of airplanes that
may need this repair/replacement:
Short Modification--Option A *
------------------------------------------------------------------------
Total cost per
Labor cost Parts cost airplane per
side
------------------------------------------------------------------------
250 work-hours x $80 per hour = $9,170 per kit per $29,170
$20,000 per side. side.
------------------------------------------------------------------------
[[Page 63567]]
Middle Modification--Option B *
------------------------------------------------------------------------
Total cost per
Labor cost Parts cost airplane per
side
------------------------------------------------------------------------
280 work-hours x $80 per hour = $9,170 per kit per $31,570
$22,400 per side. side.
------------------------------------------------------------------------
Long Modification--Option C *
------------------------------------------------------------------------
Total cost per
Labor cost Parts cost airplane per
side
------------------------------------------------------------------------
320 work-hours x $80 per hour = $9,170 per kit per $34,770
$25,600 per side. side.
------------------------------------------------------------------------
Note: * Depending on airplane configuration, airplanes with
rectangular plates will need the Plate and Hardware Kit (SB237-4) at
$2,090 per side. Labor to install this kit is included in Options A,
B, and C.
Strap Only Replacement--Option D
------------------------------------------------------------------------
Total cost per
Labor cost Parts cost airplane per
side
------------------------------------------------------------------------
75 work-hours x $80 per hour = $6,190 per strap per $12,190
$6,000 per side. side.
------------------------------------------------------------------------
We estimate the following costs to do the installation of access
holes:
----------------------------------------------------------------------------------------------------------------
Total cost per Total cost on
Labor cost Parts cost airplane U.S. operators
----------------------------------------------------------------------------------------------------------------
30 work-hours x $80 per hour = $2,400........................ $1,293 $3,693 $1,015,575
----------------------------------------------------------------------------------------------------------------
We estimate the following costs to do the wing fastener
modification:
----------------------------------------------------------------------------------------------------------------
Total cost per Total cost on
Labor cost Parts cost airplane U.S. operators
----------------------------------------------------------------------------------------------------------------
8.5 work-hours x $80 per hour = $680......................... $250 $930 $255,750
----------------------------------------------------------------------------------------------------------------
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 AD.
Regulatory Findings
We have 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); 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 summary of the costs to comply with this AD (and
other information as included in the Regulatory Evaluation) and placed
it in the AD Docket. You may get a copy of this summary by sending a
request to us at the address listed under ADDRESSES. Include ``Docket
No. FAA-2009-0778; Directorate Identifier 2009-CE-040-AD'' in your
request.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
0
Accordingly, under the authority delegated to me by the Administrator,
[[Page 63568]]
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. FAA amends Sec. 39.13 by adding a new AD to read as follows:
2009-25-02 Twin Commander Aircraft LLC: Amendment 39-16119; Docket
No. FAA-2009-0778; Directorate Identifier 2009-CE-040-AD.
Effective Date
(a) This AD becomes effective on January 8, 2010.
Affected ADs
(b) None.
Applicability
(c) This AD applies to the following airplane models and serial
numbers that are certificated in any category:
------------------------------------------------------------------------
Models Serial Nos. (S/Ns)
------------------------------------------------------------------------
690............................... All S/Ns
690A.............................. All S/Ns except 11195 and 11279.
690B.............................. All S/Ns except 11361, 11383, 11527,
and 11536.
------------------------------------------------------------------------
Unsafe Condition
(d) This AD results from reports that corrosion was found
between the mating surfaces of the wing upper skin surface and the
engine mount beam support straps. We are issuing this AD to detect
and correct corrosion on the engine mount beam support straps and
upper wing skins, which could result in failure of the engine mount
beam support straps. This failure could lead to loss of the engine
and possible loss of control of the airplane.
Compliance
(e) To address this problem, you must do the following, unless
already done:
------------------------------------------------------------------------
Actions Compliance Procedures
------------------------------------------------------------------------
(1) Inspect between the Within the next 150 Follow Twin
surface of the left-hand hours time-in- Commander Aircraft
(LH) and right-hand (RH) service after LLC Alert Service
upper wing skins and the January 8, 2010 Bulletin No. 237,
engine mount beam support (the effective date dated May 13, 2005,
straps for any signs of of this AD) or pages 1 through 14.
corrosion and determine the within the next 12
extent of any corrosion months after
found. January 8, 2010
(the effective date
of this AD),
whichever occurs
first.
(2) Install modification Before further Follow the
access holes in the LH and flight after the Accomplishment
RH lower wing skins. inspection required Instructions, steps
in paragraph (e)(1) 1 through 4 and 6
of this AD. through 9, of Twin
Commander Aircraft
Corporation Custom
Kit No. 150, dated
July 8, 1994, as
specified in Twin
Commander Aircraft
LLC Alert Service
Bulletin No. 237,
dated May 13, 2005.
(3) If corrosion damage is Before further Follow Twin
found during the inspection flight after the Commander Aircraft
required in paragraph inspection required LLC Alert Service
(e)(1) of this AD, perform in paragraph (e)(1) Bulletin No. 237,
necessary modification. of this AD. dated May 13, 2005,
Part II, Options A,
B, or C, on pages
15 through 29 and
31.
(4) If corrosion damage is Before further Follow Twin
not found during the flight after the Commander Aircraft
inspection required in inspection required LLC Alert Service
paragraph (e)(1) of this in paragraph (e)(1) Bulletin No. 237,
AD, do the upper steel of this AD. dated May 13, 2005,
strap replacements. Part II, Option D,
on pages 30 and 31.
(5) Install additional wing Before further Follow Gulfstream
fasteners on the LH and RH flight after the American
wing. inspection required Corporation Service
in paragraph (e)(1) Bulletin No. 182,
of the AD. dated March 2,
1981.
------------------------------------------------------------------------
Note: Although not required by this AD, we highly recommend
compliance with Twin Commander Aircraft Corporation Service Bulletin
No. 217, Revision No. 1, dated May 26, 1993, Engine Nacelle Firewall
Reinforcement; and Twin Commander Aircraft LLC Alert Service
Bulletin No. 239, dated February 13, 2006, Outboard Flap--Inboard
Hinge Inspection & Reinforcement.
Alternative Methods of Compliance (AMOCs)
(f) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, has the authority to approve AMOCs for this AD, if requested
using the procedures found in 14 CFR 39.19. Send information to
ATTN: Vince Massey, Aerospace Engineer, FAA, Seattle ACO, 1601 Lind
Avenue, SW, Renton, Washington 98057-3356; telephone: (425) 917-
6475; fax: (425) 917-6590; email: <a href="/cdn-cgi/l/email-protection#8afce3e4e9efa4e7ebf9f9eff3caecebeba4ede5fc"><span class="__cf_email__" data-cfemail="25534c4b46400b48445656405c654344440b424a53">[email protected]</span></a>. Before using
any approved AMOC on any airplane to which the AMOC applies, notify
your appropriate principal inspector (PI) in the FAA Flight
Standards District Office (FSDO), or lacking a PI, your local FSDO.
Material Incorporated by Reference
(g) You must use Twin Commander Aircraft LLC Alert Service
Bulletin No. 237, dated May 13, 2005; Twin Commander Aircraft
Corporation Custom Kit No. 150, dated July 8, 1994; and Gulfstream
American Corporation Service Bulletin No. 182, dated March 2, 1981,
to do the actions required by this AD, unless the AD specifies
otherwise.
(1) The Director of the Federal Register approved the
incorporation by reference of this service information under 5
U.S.C. 552(a) and 1 CFR part 51.
(2) For service information identified in this AD, contact Twin
Commander Aircraft LLC, 18933--59th Avenue, NE., Arlington, WA
98223, telephone: (360) 435-9797; fax: (360) 435-1112; Internet:
<a href="http://www.twincommander.com">http://www.twincommander.com</a>.
(3) You may review copies of the service information
incorporated by reference for this AD at the FAA, Central Region,
Office of the Regional Counsel, 901 Locust, Kansas City, Missouri
64106. For information on the availability of this material at the
Central Region, call (816) 329-3768.
(4) You may also review copies of the service information
incorporated by reference for this AD 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/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
Issued in Kansas City, Missouri, on November 20, 2009.
Margaret Kline,
Acting Manager, Small Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E9-28548 Filed 12-3-09; 8:45 am]
BILLING CODE 4910-13-P
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