AD 2015-08-51
Unsafe Condition
Cracks in the main rotor spindle, which can lead to main rotor blade separation and subsequent loss of control of the helicopter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Conduct a magnetic particle inspection (MPI) on any spindle with 1,500 or more hours time-in-service (TIS) or where TIS is unknown. Replace the spindle if a crack is found before further flight. Report inspection results to the FAA within 72 hours.
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
Enstrom Helicopter Corporation Model F-28A, 280, F-28C, F-28C-2, F-28C-2R, 280C, F-28F, F-28F-R, 280F, 280FX, and 480 helicopters with main rotor spindles, part numbers 28-14282-11 and 28-14282-13.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
We are publishing a new airworthiness directive (AD) for Enstrom Helicopter Corporation (Enstrom) Model F-28A, 280, F-28C, F- 28C-2, F-28C-2R, 280C, F-28F, F-28F-R, 280F, 280FX, and 480 helicopters. This AD was sent previously to all known U.S. owners and operators of these helicopters and supersedes Emergency AD (EAD) 2015- 04-51, dated February 12, 2015. This AD requires inspecting certain main rotor spindles (spindles) for cracks and reporting the inspection results to the FAA. This AD is prompted by a fatal accident and reports of spindles with cracks. The actions specified in this AD are intended to detect a crack in a spindle and prevent loss of a main rotor blade and subsequent loss of control of the helicopter.
Document Text
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[Federal Register Volume 80, Number 95 (Monday, May 18, 2015)]
[Rules and Regulations]
[Pages 28172-28175]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2015-11732]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2015-1537; Directorate Identifier 2015-SW-014-AD;
Amendment 39-18160; AD 2015-08-51]
RIN 2120-AA64
Airworthiness Directives; The Enstrom Helicopter Corporation
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule; request for comments.
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SUMMARY: We are publishing a new airworthiness directive (AD) for
Enstrom Helicopter Corporation (Enstrom) Model F-28A, 280, F-28C, F-
28C-2, F-28C-2R, 280C, F-28F, F-28F-R, 280F, 280FX, and 480
helicopters. This AD was sent previously to all known U.S. owners and
operators of these helicopters and supersedes Emergency AD (EAD) 2015-
04-51, dated February 12, 2015. This AD requires inspecting certain
main rotor spindles (spindles) for cracks and reporting the inspection
results to the FAA. This AD is prompted by a fatal accident and reports
of spindles with cracks. The actions specified in this AD are intended
to detect a crack in a spindle and prevent loss of a main rotor blade
and subsequent loss of control of the helicopter.
DATES: This AD becomes effective June 2, 2015 to all persons except
those persons to whom it was made immediately effective by EAD 2015-08-
51, issued on April 10, 2015, which contains the requirements of this
AD.
We must receive comments on this AD by July 17, 2015.
[[Page 28173]]
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 Street, Menominee, MI; telephone
(906) 863-1200; fax (906) 863-6821; or at <a href="http://www.enstromhelicopter.com">www.enstromhelicopter.com</a>.
You may review 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, Senior Aerospace
Engineer, Chicago Aircraft Certification Office, Small Airplane
Directorate, FAA, 2300 East Devon Ave., Des Plaines, IL 60018; (847)
294-7135; email <a href="/cdn-cgi/l/email-protection#6b0c190e0c04191245060208030a0702002b0d0a0a450c041d"><span class="__cf_email__" data-cfemail="40273225272f32396e2d292328212c292b002621216e272f36">[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
On February 12, 2015, we issued EAD 2015-04-51, which was prompted
by a fatal accident. Preliminary results of the investigation indicated
that the accident was caused by a crack in the spindle, which resulted
in the main rotor blade separating from the helicopter. The crack was
discovered at the last thread of the spindle retention nut threads.
While the investigation could not determine when the crack initiated,
it was able to determine that the crack existed, undetected, for a
significant amount of time before the separation. EAD 2015-04-51
required, before further flight, conducting a magnetic particle
inspection (MPI) in any spindle that had 5,000 or more hours time-in-
service (TIS) or where the hours TIS of the spindle is not known. If
there was a crack in the spindle, EAD 2015-04-51 required replacing it
before further flight. EAD 2015-04-51 also required reporting the
inspection results to the FAA within 72 hours.
Since we issued EAD 2015-04-51, inspection reports received by the
FAA indicate approximately 20% of the spindles reported with TIS data
had evidence of cracks. The FAA also received inspection reports of
spindles without TIS data which did not have evidence of cracks. The
inspection reports include spindles with cracks at less than 5,000
hours TIS. With analysis of available data, we determined the need to
expand the applicability to include spindles with 1,500 or more hours
TIS.
On April 10, 2015, we issued EAD 2015-08-51, which supersedes EAD
2015-04-51. EAD 2015-08-51 retains all of the requirements of EAD 2014-
04-51 except it reduces the TIS of the spindles to be inspected from
5,000 hours to 1,500 hours. EAD 2015-08-51 was sent previously to all
known U.S. owners and operators of these helicopters.
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 these same type
designs.
Related Service Information
Enstrom has issued Service Directive Bulletin No. 0119, Revision 1,
dated April 1, 2015, for all serial numbered Model F-28A, F-28C, F-28F,
280, 280C, 280F, and 280FX helicopters with a main rotor spindle, part
number (P/N) 28-14282-11 and 28-14282-13. Enstrom has also issued
Service Directive Bulletin No. T-050, Revision 1, dated April 1, 2015,
for Model 480 helicopters, serial numbers 5001 through 5004 and 5006,
and with a main rotor spindle, P/N 28-14282-13, except those aircraft
modified with tension-torsion straps. Both service directives specify,
for any spindle that has been in service more than 3,500 hours, within
5 hours TIS, sending the spindle to Enstrom for an MPI. For any spindle
with less than 3,500 hours TIS, the service directives specify sending
the spindle to Enstrom for an MPI at or before it reaches 3,500 hours
TIS. The service directives also specify repeating the MPI every 300
hours for spindles with over 3,500 hours TIS.
AD Requirements
This AD requires conducting an MPI before further flight to
determine if a crack exists in any spindle that has 1,500 or more hours
TIS or where the hours TIS of the spindle is not known. If there is a
crack in the spindle, this AD requires replacing it before further
flight. The MPI of the spindle must be conducted by a Level II or Level
III inspector qualified in the MPI method in the Aeronautics Sector
according to the EN4179 or NAS410 standard or equivalent. This AD also
requires reporting certain information to the FAA within 72 hours.
Differences Between This AD and the Service Information
This AD requires that the MPI be conducted by a Level II or Level
III inspector or equivalent and that the results of the MPI be reported
to the FAA, whereas the service information specifies that the MPI be
accomplished by or reported to Enstrom. This AD requires an MPI on
spindles with 1,500 or more hours TIS, whereas the service information
specifies performing an initial MPI on spindles with 3,500 or more
hours TIS. This AD does not require a recurring inspection, whereas the
service information specifies to repeat the MPI every 300 hours TIS for
spindles with over 3,500 hours TIS. This AD requires the MPI before
further
[[Page 28174]]
flight, whereas the service information specifies that it be
accomplished within 5 hours TIS.
Interim Action
We consider this AD to be an interim action. The inspection reports
that are required by this AD will enable us to obtain better insight
into the root cause and extent of the cracking, and eventually to
develop final action to address the unsafe condition. Once final action
has been identified, we might consider further rulemaking.
Costs of Compliance
We estimate that this AD affects 323 helicopters of U.S. Registry
and that operators may incur the following costs to comply with this
AD. Inspecting the spindles will take about 15 work-hours per
helicopter and reporting the required inspection information will take
about 0.5 work-hour. We estimate an average labor rate of $85 per work-
hour, for a total cost of $1,318 per helicopter and $425,714 for the
U.S. fleet. Replacing a spindle will cost $8,164 for parts and no
additional work-hours.
Paperwork Reduction Act
A federal agency may not conduct or sponsor, and a person is not
required to respond to, nor shall a person be subject to penalty for
failure to comply with a collection of information subject to the
requirements of the Paperwork Reduction Act unless that collection of
information displays a current valid OMB control number. The control
number for the collection of information required by this AD is 2120-
0056. The paperwork cost associated with this AD has been detailed in
the Costs of Compliance section of this document and includes time for
reviewing instructions, as well as completing and reviewing the
collection of information. Therefore, all reporting required by this AD
is mandatory. Comments concerning the accuracy of this burden and
suggestions for reducing the burden should be directed to the FAA at
800 Independence Ave. SW., Washington, DC 20591. ATTN: Information
Collection Clearance Officer, AES-200.
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 found and
continue to find that the risk to the flying public justifies waiving
notice and comment prior to the adoption of this rule because the
previously described unsafe condition can adversely affect the
controllability of the helicopter and the initial required action must
be accomplished before further flight.
Since it was found that immediate corrective action was required,
notice and opportunity for prior public comment before issuing this AD
were impracticable and contrary to the public interest and good cause
existed to make the AD effective immediately by EAD 2015-08-51, issued
on April 10, 2015, to all known U.S. owners and operators of these
helicopters. These conditions still exist and the AD is hereby
published in the Federal Register as an amendment to section 39.13 of
the Federal Aviation Regulations (14 CFR 39.13) to make it effective to
all persons.
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 airworthiness
directive (AD):
2015-08-51 The Enstrom Helicopter Corporation (Enstrom): Amendment
39-18160; Docket No. FAA-2015-1537; Directorate Identifier 2015-SW-
014-AD.
(a) Applicability
This AD applies to Enstrom Model F-28A, 280, F-28C, F-28C-2, F-
28C-2R, 280C, F-28F, F-28F-R, 280F, and 280FX helicopters, all
serial numbers; and Enstrom Model 480 helicopters, serial numbers
5001 through 5006; with a main rotor spindle (spindle), part number
(P/N) 28-14282-11 or 28-14282-13, installed, certificated in any
category. This AD applies to any helicopter that has a spindle with
1,500 or more hours time-in-service (TIS) or where the hours TIS of
the spindle is not known.
(b) Unsafe Condition
This AD defines the unsafe condition as a crack in the spindle,
which, if not detected, could result in loss of a main rotor blade
and subsequent loss of control of the helicopter.
(c) Affected ADs
This AD supersedes Emergency AD 2015-04-51, Directorate
Identifier 2015-SW-002-AD, dated February 12, 2015.
(d) Effective Date
This AD becomes effective June 2, 2015 to all persons except
those persons to whom it was made immediately effective by Emergency
AD 2015-08-51, issued on April 10, 2015, which contains the
requirements of this AD.
(e) Compliance
You are responsible for performing each action required by this
AD within the specified compliance time unless it has been
accomplished on or after February 11, 2015.
[[Page 28175]]
(f) Required Actions
(1) Before further flight, conduct a magnetic particle
inspection (MPI) of the spindle to determine if a crack exists,
paying particular attention to the threaded portion of the spindle.
The MPI of the spindle must be conducted by a Level II or Level III
inspector qualified in the MPI in the Aeronautics Sector according
to the EN4179 or NAS410 standard or equivalent. If there is a crack
in the spindle, replace it with an airworthy spindle before further
flight.
(2) Within 72 hours after accomplishing the MPI, report the
information requested in Appendix 1 to this AD by mail to the
Manager, Chicago Aircraft Certification Office, Federal Aviation
Administration, ATTN: Gregory J. Michalik, 2300 East Devon Ave., Des
Plaines, IL, 60018; by fax to (847) 294-7834; or email to
<a href="/cdn-cgi/l/email-protection#9cfbeef9fbf3eee5b2f1f5fff4fdf0f5f7dcfafdfdb2fbf3ea"><span class="__cf_email__" data-cfemail="fc9b8e999b938e85d291959f949d909597bc9a9d9dd29b938a">[email protected]</span></a>.
(g) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Chicago Aircraft Certification Office, FAA, may
approve AMOCs for this AD. Send your proposal to: Gregory J.
Michalik, Senior Aerospace Engineer, Chicago Aircraft Certification
Office, Small Airplane Directorate, FAA, 2300 East Devon Ave., Des
Plaines, IL, 60018; (847) 294-7135; email <a href="/cdn-cgi/l/email-protection#8ee9fcebe9e1fcf7a0e3e7ede6efe2e7e5cee8efefa0e9e1f8"><span class="__cf_email__" data-cfemail="91f6e3f4f6fee3e8bffcf8f2f9f0fdf8fad1f7f0f0bff6fee7">[email protected]</span></a>.
(2) For operations conducted under a 14 CFR part 119 operating
certificate or under 14 CFR 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.
(3) Any AMOC approved previously in accordance with EAD 2015-04-
51, dated February 12, 2015, is approved as an AMOC for the
corresponding requirements in paragraph (f)(1) of this AD.
(h) Additional Information
Enstrom Helicopter Corporation Service Directive Bulletin No.
0119, Revision 1, dated April 1, 2015, and Enstrom Helicopter
Corporation Service Directive Bulletin No. T-050, Revision 1, dated
April 1, 2015, which are not incorporated by reference, contain
additional information about the subject of this AD. For service
information identified in this AD, contact Enstrom Helicopter
Corporation, 2209 22nd Street, Menominee, MI; telephone (906) 863-
1200; fax (906) 863-6821; or at <a href="http://www.enstromhelicopter.com">www.enstromhelicopter.com</a>. You may
review this service information at the FAA, Office of the Regional
Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth,
Texas 76137.
(i) Subject
Joint Aircraft Service Component (JASC) Code: 6220, Main Rotor
Head.
Appendix 1 to AD 2015-08-51
Spindle Inspection (Sample Format)
Provide the following information by mail to the Manager,
Chicago Aircraft Certification Office, Federal Aviation
Administration, ATTN: Gregory J. Michalik, 2300 East Devon Ave., Des
Plaines, IL, 60018; by fax to (847) 294-7834; or email to
<a href="/cdn-cgi/l/email-protection#6b0c190e0c04191245060208030a0702002b0d0a0a450c041d"><span class="__cf_email__" data-cfemail="e1869384868e9398cf8c888289808d888aa1878080cf868e97">[email protected]</span></a>.
Aircraft Registration No.:
Helicopter Model:
Helicopter Serial Number:
Helicopter Owner or Operator:
Contact Phone No.:
Spindle Part Number and Serial Number:
Total Hours Time-in-Service (TIS) on Spindle:
Total Hours TIS on Helicopter (if hours TIS on spindle were not
available):
Who Performed the Inspection:
Date and Location Inspection was Accomplished:
Crack Found? If yes, describe the crack size, location, orientation
(provide a sketch or picture):
Provide Any Other Comments:
Issued in Fort Worth, Texas, on May 8, 2015.
Lance T. Gant,
Acting Directorate Manager, Rotorcraft Directorate, Aircraft
Certification Service.
[FR Doc. 2015-11732 Filed 5-15-15; 8:45 am]
BILLING CODE 4910-13-P
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