AD 2011-26-10
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Enstrom | Various | Airworthiness Directives; Enstrom Helicopter Corporation Helicopters |
Unsafe Condition
Failure of the cyclic trim system, specifically involving trim relays part-number KUP14D55-472, M83536/10-015M, or M83536/10-024M, which can lead to reduced controllability and potential loss of control of the helicopter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Replace the actuator and limit switch bracket in the lateral and longitudinal trim actuator assemblies to provide a positive stop for the trim actuator. Perform operational (ground) and flight tests to verify the trim relay is functioning correctly after modification.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 5 hours time-in-service (TIS) or at the next annual or 100 hour time-in-service inspection, whichever occurs first.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Enstrom Helicopter Corporation Model F-28C, F-28C-2, F-28F, 280C, 280F, 280FX, TH-28, 480, and 480B helicopters equipped with trim relays part-number KUP14D55-472, M83536/10-015M, or M83536/10-024M.
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 Enstrom Helicopter Corporation (Enstrom) Model F-28C, F-28C-2, F-28F, 280C, 280F, 280FX TH-28, 480, and 480B helicopters with certain trim relays to require modifying and testing the lateral and longitudinal cyclic trim actuator assemblies. This AD was prompted by four failures in the cyclic trim system on certain Enstrom model helicopters that resulted in reduced controllability of the helicopter. These actions are intended to prevent failure of the cyclic trim system and subsequent loss of control of the helicopter.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 77, Number 4 (Friday, January 6, 2012)]
[Rules and Regulations]
[Pages 729-731]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2011-32895]
========================================================================
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. 77, No. 4 / Friday, January 6, 2012 / Rules
and Regulations
[[Page 729]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2011-1382; Directorate Identifier 2011-SW-053-AD;
Amendment 39-16900; AD 2011-26-10]
RIN 2120-AA64
Airworthiness Directives; Enstrom Helicopter Corporation
Helicopters
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule; request for comments.
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SUMMARY: We are adopting a new airworthiness directive (AD) for Enstrom
Helicopter Corporation (Enstrom) Model F-28C, F-28C-2, F-28F, 280C,
280F, 280FX TH-28, 480, and 480B helicopters with certain trim relays
to require modifying and testing the lateral and longitudinal cyclic
trim actuator assemblies. This AD was prompted by four failures in the
cyclic trim system on certain Enstrom model helicopters that resulted
in reduced controllability of the helicopter. These actions are
intended to prevent failure of the cyclic trim system and subsequent
loss of control of the helicopter.
DATES: This AD becomes effective January 23, 2012.
The Director of the Federal Register approved the incorporation by
reference of certain documents listed in this AD as of January 23,
2012.
We must receive comments on this AD by March 6, 2012.
ADDRESSES: You may send comments by any of the following methods:
<bullet> Federal eRulemaking Docket: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a>. Follow the online instructions for sending your
comments electronically.
<bullet> Fax: (202) 493-2251.
<bullet> Mail: Send comments to the U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590-0001.
<bullet> Hand Delivery: Deliver to the ``Mail'' address between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
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 this AD, the economic
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.
For service information identified in this AD, contact Enstrom
Helicopter Corporation, 2209 22nd St., Menominee, Michigan, 49858-0490;
telephone: (906) 863-1200; email:
<a href="/cdn-cgi/l/email-protection#3d5e484e495250584f4e584f4b545e587d58534e494f5250555851545e524d49584f135e5250"><span class="__cf_email__" data-cfemail="54372127203b393126273126223d373114313a2720263b393c31383d373b242031267a373b39">[email protected]</span></a>; Web site: <a href="http://www.enstromhelicopter.com/enstrom_new/enstrom_support_tec.html">http://www.enstromhelicopter.com/enstrom_new/enstrom_support_tec.html</a>. You
may review copies of the referenced service information at the FAA,
Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd.,
Room 663, Fort Worth, Texas 76137.
FOR FURTHER INFORMATION CONTACT: Gregory J. Michalik, Enstrom Program
Manager, FAA, Chicago Aircraft Certification Office, 2300 East Devon
Avenue, Room 107, Des Plaines, Illinois 60018; telephone (847) 294-
7135; fax (847) 294-7834; email: <a href="/cdn-cgi/l/email-protection#fa9d889f9d958883d4979399929b969391ba9c9b9bd49d958c"><span class="__cf_email__" data-cfemail="3f584d5a58504d461152565c575e5356547f595e5e11585049">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Comments Invited
This AD is a final rule that involves requirements affecting flight
safety, and we did not provide you with notice and an opportunity to
provide your comments prior to it becoming effective. However, we
invite you to participate in this rulemaking by submitting written
comments, data, or views. We also invite comments relating to the
economic, environmental, energy, or federalism impacts that resulted
from adopting this AD. The most helpful comments reference a specific
portion of the AD, explain the reason for any recommended change, and
include supporting data. To ensure the docket does not contain
duplicate comments, commenters should send only one copy of written
comments, or if comments are filed electronically, commenters should
submit them only one time. We will file in the docket all comments that
we receive, as well as a report summarizing each substantive public
contact with FAA personnel concerning this rulemaking during the
comment period. We will consider all the comments we receive and may
conduct additional rulemaking based on those comments.
Discussion
We are adopting a new AD for the Enstrom Model F-28C, F-28C-2, F-
28F, 280C, 280F, 280FX, TH-28, 480, and 480B helicopters with a trim
relay, part-number (P/N) KUP14D55-472, M83536/10-015M, or M83536/10-
024M. This AD does not apply to the specified helicopters with a
reversible trim motor, P/N 28-16621 (Ford Motor Company C1AZ-14553A) or
P/N AD1R-10 (Signal Electric). This AD requires modifying the lateral
and longitudinal trim actuator assemblies by replacing the actuator and
limit switch bracket to provide a positive stop for the trim actuator.
In the event of a trim actuator runaway, the new bracket will stop the
actuator, causing the circuit breaker to trip before any significant
loss of control occurs. After the trim actuator assemblies are
modified, this AD requires performing operational (ground) and flight
tests to determine that the trim relay is working correctly. This AD
was prompted by reports of 4 failures in the cyclic trim system in the
field, 2 that occurred on the Enstrom Model 480B helicopter and 2 that
occurred on the Enstrom Model F28 helicopter. These failures resulted
in reduced controllability of the helicopter. We are issuing this AD to
prevent failure of the cyclic trim system and subsequent loss of
control of the helicopter.
FAA's Determination
We are issuing this AD because we evaluated all the relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other products of the same type design.
[[Page 730]]
Related Service Information
We reviewed Enstrom Service Directive Bulletin (SDB) No. 0110,
Revision 3, dated July 6, 2011 (SDB 0110), for Model F-28C, F-28C-2, F-
28F, 280C, 280F, and 280FX helicopters; and Enstrom SDB No. T-039,
Revision 3, dated July 6, 2011 (SDB T-039), for Model TH-28, 480, and
480B helicopters. SDB 0110 specifies, for helicopters with a trim
relay, P/N KUP14D55-472, M83536/10-015M, or M83536/10-024M, procedures
for modifying the lateral and longitudinal trim actuator assembly using
the cyclic trim assembly kit (modification kit), P/N 28-01063-1, and
specifies performing an operational check and flight test to determine
the trim is operating correctly after the modification. SDB T-039
specifies, for helicopters with a trim relay, P/N M83536/10-024M,
procedures for modifying the lateral and longitudinal trim actuator
assembly using the modification kit, P/N 4230045-1, and specifies
performing an operational check and flight test to determine the trim
is operating correctly after the modification. The SDBs state that the
modification kits contain the upgraded bracket.
AD Requirements
This AD requires, within 5 hours time-in-service (TIS) or at the
next annual or 100 hour time-in-service inspection, whichever occurs
first, the following actions:
<bullet> For the Enstrom Model F-28C, F-28C-2, F-28F, 280C, 280F,
and 280FX helicopters with a trim relay, P/N KUP14D55-472, M83536/10-
015M, or M83536/10-024M, modify the lateral and longitudinal trim
actuator assembly using the modification kit, P/N 28-01063-1.
<bullet> For the Enstrom Model TH-28, 480, and 480B helicopter with
a trim relay, P/N M83536/10-024M, modify the lateral and longitudinal
trim actuator assembly using the modification kit, P/N 4230045-1.
<bullet> For all affected helicopters, after accomplishing the
modification of the lateral and longitudinal trim actuator assemblies
and before further flight, perform an operational test and flight test
to determine the trim is operating correctly.
The actions required by this AD are to be accomplished by following
specified portions of the SDBs described previously.
Differences Between This AD and the Service Information
The SDBs specify, before further flight, to insert a special
addendum into the Emergency Procedures section of the Flight Manual,
and this AD does not require this action.
Costs of Compliance
We estimate that this AD will affect 207 helicopters of U.S.
Registry. We estimate that operators may incur the following costs in
order to comply with this AD. For Model 480, 480B, and TH-28, modifying
the actuator assembly will require 4 work hours at a cost of $85 per
hour and parts will cost $327; the cost per helicopter will be $667.
For Model 280C, 280F, 280FX, F-28C, F-28C-2, and F-28F, modifying the
actuator assembly will require 4 work hours at a cost of $85 per hour;
parts will cost $383; and the cost per helicopter will be $723.
FAA's Justification and Determination of the Effective Date
Providing an opportunity for public comments prior to adopting
these AD requirements would delay implementing the safety actions
needed to correct this known unsafe condition. Therefore, we find that
the risk to the flying public justifies waiving notice and comment
prior to the adoption of this rule because the required corrective
actions must be accomplished within 5 hours time-in-service, a very
short time period based on the average flight-hour utilization rate of
these helicopters.
Since an unsafe condition exists that requires the immediate
adoption of this AD, we determined that notice and opportunity for
public comment before issuing this AD are impracticable and contrary to
the public interest and that good cause exists for making this
amendment effective in less than 30 days.
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, I certify that this AD:
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);
3. Will not affect intrastate aviation in Alaska to the extent that
it justifies making a regulatory distinction; 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 an economic evaluation of the estimated costs to comply
with this AD and placed it in the AD docket.
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:
2011-26-10 Enstrom Helicopter Corporation: Amendment 39-16900;
Docket No. FAA-2011-1382; Directorate Identifier 2011-SW-053-AD.
(a) Applicability
This AD applies to the Enstrom Model F-28C, F-28C-2, F-28F,
280C, 280F, 280FX, TH-28, 480, and 480B helicopters with a trim
relay, part-number (P/N) KUP14D55-472, M83536/10-015M, or M83536/10-
024M, certificated in any category.
Note 1: This AD does not apply to the specified helicopters
with a reversible trim motor, P/N 28-16621 (Ford Motor Company C1AZ-
14553A) or P/N AD1R-10 (Signal Electric).
[[Page 731]]
(b) Unsafe Condition
This AD defines the unsafe condition as a failure in the cyclic
trim system. This condition could result in reduced controllability
of the helicopter and subsequent loss of control of the helicopter.
(c) Effective Date
This airworthiness directive (AD) becomes effective January 23,
2012.
(d) Compliance
You are responsible for performing each action required by this
AD within the specified compliance time unless it has already been
accomplished prior to that time.
(e) Required Actions
Within 5 hours time-in-service (TIS) or at the next annual or
100 TIS inspection, whichever comes first:
(1) For the Enstrom Model F-28C, F-28C-2, F-28F, 280C, 280F, and
280FX helicopters, modify the lateral and longitudinal trim actuator
assemblies using the cyclic trim assembly kit (modification kit), P/
N 28-01063-1, in accordance with the instructions in paragraph 6.1
of the Enstrom Service Directive Bulletin (SDB) No. 0110, Revision
3, dated July 6, 2011 (SDB No. 0110 R3), except when the
instructions specify using ``Aeroshell 22 grease'' or ``VC-3 Vibra-
tite thread locker,'' you may use an equivalent product.
(2) For the Enstrom Model TH-28, 480, and 480B helicopters,
modify the lateral and longitudinal trim actuator assemblies using
the modification kit, P/N 4230045-1, in accordance with the
instructions in paragraph 6.1 of the Enstrom SDB No. T-039, Revision
3, dated July 6, 2011 (SDB No. T-039 R3), except when the
instructions specify using ``Aeroshell 22 grease'' or ``VC-3 Vibra-
tite thread locker,'' you may use an equivalent product, and you are
not required to contact Enstrom Customer Service.
(3) After modifying the lateral and longitudinal trim actuator
assemblies in accordance with paragraphs (e)(1) or (e)(2) of this
AD, before further flight, operationally test the trim limits in
accordance with paragraph 6.2. of the SDB for your model helicopter,
and determine during a flight test whether there is appropriate trim
authority in accordance with paragraph 6.3. of the SDB for your
model helicopter.
(f) Special Flight Permits
A one-time special-flight permit may be issued in accordance
with 14 CFR 21.197 and 21.199 provided the helicopter is operated
with the trim system circuit breaker pulled.
(g) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Safety Management Group, FAA, may approve AMOCs
for this AD. Send your proposal to: Gregory J. Michalik, Enstrom
Program Manager, FAA, Chicago Aircraft Certification Office, 2300
East Devon Avenue, Room 107, Des Plaines, Illinois 60018; telephone
(847) 294-7135; fax (847) 294-7834; email: <a href="/cdn-cgi/l/email-protection#9ff8edfaf8f0ede6b1f2f6fcf7fef3f6f4dff9fefeb1f8f0e9"><span class="__cf_email__" data-cfemail="7e190c1b19110c075013171d161f1217153e181f1f50191108">[email protected]</span></a>.
(2) For operations conducted under a Part 119 operating
certificate or under Part 91, Subpart K, we suggest that you notify
your principal inspector or lacking a principal inspector, the
manager of the local flight standards district office or certificate
holding district office before operating any aircraft complying with
this AD through an AMOC.
(h) Subject
Joint Aircraft Service Component (JASC) Code: 6710: Main Rotor
Control.
(i) Material Incorporated by Reference
You must use the specified portions of the following service
information to do the specified actions required by this AD. 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) Enstrom Service Directive Bulletin No. 0110, Revision 3,
dated July 6, 2011, for the Model F-28C, F-28C-2, F-28F, 280C, 280F;
and
(3) 280FX or Enstrom Service Directive Bulletin No. T-039,
Revision 3, dated July 6, 2011, for the Model TH-28, 480, and 480B.
(4) For service information identified in this AD, contact
Enstrom Helicopter Corporation, 2209 22nd St., Menominee, Michigan
49858-0490; telephone: (906) 863-1200; email:
<a href="/cdn-cgi/l/email-protection#a4c7d1d7d0cbc9c1d6d7c1d6d2cdc7c1e4c1cad7d0d6cbc9ccc1c8cdc7cbd4d0c1d68ac7cbc9"><span class="__cf_email__" data-cfemail="e4879197908b898196978196928d8781a4818a9790968b898c81888d878b94908196ca878b89">[email protected]</span></a>; Web site: <a href="http://www.enstromhelicopter.com/enstrom_new/enstrom_support_tec.html">http://www.enstromhelicopter.com/enstrom_new/enstrom_support_tec.html</a>.
(5) You may review copies of the referenced service information
at the FAA, Office of the Regional Counsel, Southwest Region, 2601
Meacham Blvd., Room 663, Fort Worth, Texas 76137 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.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 Fort Worth, Texas, on December 14, 2011.
M. Monica Merritt,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2011-32895 Filed 1-5-12; 8:45 am]
BILLING CODE 4910-13-P
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