Document ID: FAA-2017-1191-0001
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: The Enstrom Helicopter Corporation Helicopters
Posted Date: 2017-12-20T05:00Z

[Federal Register Volume 82, Number 243 (Wednesday, December 20, 2017)]
[Rules and Regulations]
[Pages 60295-60297]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-27268]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-1191; Product Identifier 2017-SW-046-AD; Amendment 
39-19134; AD 2017-26-03]
RIN 2120-AA64

Airworthiness Directives; The Enstrom Helicopter Corporation 
Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: We are adopting a new airworthiness directive (AD) for the 
Enstrom Helicopter Corporation (Enstrom) Model F-28, F-28A, F-28C, F-
28C-2, F-28C-2R, F-28F, F-28F-R, TH-28, 280, 280C, 280F, 280FX, 480, 
and 480B helicopters. This AD requires inspecting certain rod end 
bearing assemblies. This AD is prompted by an accident. The actions of 
this AD are intended to prevent an unsafe condition on these 
helicopters.

DATES: This AD becomes effective January 4, 2018.
    The Director of the Federal Register approved the incorporation by 
reference of certain documents listed in this AD as of January 4, 2018.
    We must receive comments on this AD by February 20, 2018.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Docket: Go to http://www.regulations.gov. Follow the online instructions for sending your 
comments electronically.
     Fax: 202-493-2251.
     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.
     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 http://www.regulations.gov by searching for and locating Docket No. FAA-2017-
1191; 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, any incorporated-by-reference service information, 
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 final rule, contact 
Enstrom Helicopter Corporation, 2209 22nd Street, Menominee, MI; 
telephone (906) 863-1200; fax (906) 863-6821; or at 
www.enstromhelicopter.com. You may review the referenced service 
information at the FAA, Office of the Regional Counsel, Southwest 
Region, 10101 Hillwood Pkwy, Room 6N-321, Fort Worth, TX 76177. It is 
also available on the internet at http://www.regulations.gov by 
searching for and locating Docket No. FAA-2017-1191.

FOR FURTHER INFORMATION CONTACT: Manzoor Javed, Senior Aerospace 
Engineer, Chicago ACO Branch, Compliance and Airworthiness Division, 
Aircraft Certification Service, FAA, 2300 East Devon Ave., Des Plaines, 
IL 60018; telephone (847) 294-8112; email [email protected].

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 Enstrom Model F-28, F-28A, F-28C, F-
28C-2, F-28C-2R, F-28F, F-28F-R, TH-28, 280, 280C, 280F, 280FX, 480, 
and 480B helicopters with a rod end bearing assembly (bearing assembly) 
part number (P/N) 01-824-08E-011, 09455-01-824-08E-011, ECD091-1, 
ASMK8T, M81935/1-08K, MS21242S8K, or MTK8 installed. We received a 
report of an accident involving an Enstrom Model 480B helicopter in 
which one of the main rotor (M/R) blades departed in-flight. The 
preliminary investigation indicated that failure of a rod end bearing 
assembly of one of the M/R hydraulic damper assemblies may have caused 
the M/R blade to depart from the helicopter. Based on a partially 
visible marking, the FAA believes the failed part is assembly P/N 
ECD091-1, vendor P/N 09455-01-824-08E-011. Analysis of the failed 
assembly revealed corrosion in the root of the threaded portion of the 
rod end. Enstrom identified a potential failure mode whereby failure of 
the rod end bearing assembly may result in the loss of the M/R blade. 
Because there is no indication of a specific manufacturing or design 
issue that would limit the potential for this corrosion to have 
occurred on other similarly-designed rod ends, the FAA determined it 
necessary to require an inspection of all approved rod end P/Ns.
    Accordingly, this AD requires, within 5 hours time-in-service 
(TIS), a one-time inspection of the bearing assemblies for corrosion on 
the threaded portion of the rod end. If there is any corrosion, this AD 
requires replacing the bearing assembly before further flight. This AD 
also requires reporting information about the inspection to the FAA 
within 10 days.
    The actions specified by this AD are intended to detect corrosion 
in the bearing assembly to prevent failure of the rod end, loss of an 
M/R blade, and subsequent loss of control of the helicopter. Additional 
inspections at longer intervals may also be necessary.

[[Page 60296]]

We plan to publish a notice of proposed rulemaking to give the public 
an opportunity to comment on those long-term requirements.

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 helicopters of these same type 
designs.

Related Service Information Under 1 CFR Part 51

    Enstrom has issued Service Directive Bulletin (SDB) No. 0127, 
Revision 1, dated October 6, 2017, for Model F-28, F-28A, F-28C, F-28C-
2, F-28C-2R, F-28F, F-28F-R, 280, 280C, 280F, and 280FX helicopters and 
SDB No. T-058, dated August 2, 2017, for Model TH-28, 480, and 480B 
helicopters. This service information provides procedures for 
inspecting certain vendor specific bearing assemblies P/N ECD091-1 for 
corrosion on the threaded portion of the rod end.
    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.

AD Requirements

    This AD requires, within 5 hours TIS, inspecting each M/R hydraulic 
damper bearing assembly P/N ECD091-1, and for model F-28, F-28A, F-28C, 
F-28C-2, F-28C-2R, F-28F, F-28F-R, 280, 280C, 280F, and 280FX 
helicopters each belt tension shaft bearing assembly P/N 01-824-08E-
011, 09455-01-824-08E-011, ASMK8T, ECD091-1, MTK8, M81935/1-08K, and 
MS21242S8K, for corrosion at the root of the thread on the rod end with 
a 5X or higher power magnifying glass. If there is any corrosion, this 
AD requires replacing the bearing assembly before further flight.
    This AD also requires, within 10 days after completing each 
inspection, reporting the findings of the inspection to the FAA's 
Chicago ACO Branch, including: The owner's contact information, 
helicopter registration number and model, date of the inspection, total 
hours of the bearing assembly and helicopter, bearing assembly serial 
number, the location of any corrosion, and a description of any 
corrosion.

Differences Between This AD and the Service Information

    The service information specifies repeating the visual inspection 
for corrosion at every 100 hour or annual inspection, while this AD 
does not, as this time interval would allow for sufficient time for 
notice and comment.
    Also, the service information only applies to bearing assembly P/N 
ECD091-1 and only specifies performing an inspection if marked with 
vendor P/N 09455-01-824-08E-011 or if the marking is missing or 
illegible. This AD applies to all P/N ECD091-1, 09455-01-824-08E-011, 
MTK8, ASMK8T, 01-824-08E-011, M81935/1-08K, and MS21242S8K bearing 
assemblies. Because the FAA does not have any data that positively 
confirms the root cause as a manufacturing batch, the AD requires 
inspections on all P/Ns of the same type design. The data received 
about the initial inspections will be used to determine the effectivity 
of any follow-on actions.
    Finally, the service information specifies reporting the inspection 
findings to Enstrom, while this AD requires reporting the findings to 
the FAA.

Interim Action

    We consider this AD interim action. The inspection reports that are 
required by this AD will enable us to obtain better insight into the 
nature of the corrosion and 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 513 helicopters of U.S. Registry.
    At an average labor rate of $85 per work-hour, we estimate that 
operators may incur the following costs in order to comply with this 
AD.
    Inspecting the bearing assemblies will require 5 work-hours, for a 
cost per helicopter of $425 and a total cost of $218,025 to the U.S. 
fleet.
    Reporting the inspection results required by this AD will require 
about 0.5 work-hour, for a cost per helicopter of $43, and a total cost 
of $22,059 to the U.S. fleet.
    If required, replacing one bearing assembly will not incur any 
additional work-hours, and required parts will cost $410, for a cost 
per helicopter of $410.

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

    An unsafe condition exists that requires the immediate adoption of 
this AD without providing an opportunity for public comments prior to 
adoption. The FAA has found that the risk to the flying public 
justifies waiving notice and comment prior to adoption of this rule 
because the bearing assembly inspection required by this AD must be 
accomplished within 5 hours TIS. Therefore, we find good cause that 
notice and opportunity for prior public comment are impracticable. In 
addition, for the reason(s) stated above, we find 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

[[Page 60297]]

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):

2017-26-03 The Enstrom Helicopter Corporation: Amendment 39-19134; 
Docket No. FAA-2017-1191; Product Identifier 2017-SW-046-AD.

(a) Applicability

    This AD applies to the Enstrom Helicopter Corporation (Enstrom) 
Model F-28, F-28A, F-28C, F-28C-2, F-28C-2R, F-28F, F-28F-R, TH-28, 
280, 280C, 280F, 280FX, 480, and 480B helicopters, certificated in 
any category, with a rod end bearing assembly (bearing assembly) P/N 
01-824-08E-011, 09455-01-824-08E-011, ECD091-1, ASMK8T, M81935/1-
08K, MS21242S8K, or MTK8 installed.

 (b) Unsafe Condition

    This AD defines the unsafe condition as corrosion on a bearing 
assembly rod end thread. This condition could result in a crack in 
the bearing assembly, failure of the rod end resulting in loss of a 
main rotor blade, and loss of control of the helicopter.

 (c) Effective Date

    This AD becomes effective January 4, 2018.

 (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

    (1) Within 5 hours time-in-service (TIS), using a 5X or higher 
power magnifying glass, inspect each main rotor damper bearing 
assembly for corrosion on the threaded portion of the rod end as 
shown in Figure 1 of Enstrom Service Directive Bulletin (SDB) No. 
0127, Revision 1, dated October 6, 2017 (SDB 0127), for Model F-28, 
F-28A, F-28C, F-28C-2, F-28C-2R, F-28F, F-28F-R, 280, 280C, 280F, 
and 280FX helicopters or Enstrom SDB No. T-058, dated August 2, 2017 
(SDB T-058), for model TH-28, 480, and 480B helicopters, as 
appropriate for your model helicopter. If there is any corrosion, 
before further flight, replace the bearing assembly.
    (2) For Model F-28, F-28A, F-28C, F-28C-2, F-28C-2R, F-28F, F-
28F-R, 280, 280C, 280F, and 280FX helicopters, within 5 hours TIS, 
using a 5X or higher power magnifying glass, inspect each belt 
tension shaft rod end bearing assembly for corrosion on the threaded 
portion of the rod end as shown in Figure 1 of SDB 0127. If there is 
any corrosion, before further flight, replace the bearing assembly.
    (3) Within 10 days after completing the inspections required by 
paragraph (e)(1) and (e)(2) of this AD, report the findings of each 
inspection, including the helicopter owner, address, telephone 
number, email address, helicopter model, helicopter registration 
number, date of inspection, total hours TIS of the helicopter, total 
hours TIS of the bearing, bearing assembly serial number, location 
of any corrosion, and a description of any corrosion, by mail or 
email to the individual listed in paragraph (g)(1) of this AD.

 (f) Paperwork Reduction Act Burden Statement

    A federal agency may not conduct or sponsor, and a person is not 
required to respond to, nor shall a person be subject to a 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 OMB Control Number for this information collection is 
2120-0056. Public reporting for this collection of information is 
estimated to be approximately 30 minutes per response, including the 
time for reviewing instructions, completing and reviewing the 
collection of information. All responses to this collection of 
information are 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.

 (g) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Chicago ACO Branch, Compliance and 
Airworthiness Division, Aircraft Certification Service, FAA, may 
approve AMOCs for this AD. Send your proposal to: Manzoor Javed, 
Senior Aerospace Engineer, Chicago ACO Branch, Compliance and 
Airworthiness Division, Aircraft Certification Service, FAA, 2300 
East Devon Ave., Des Plaines, IL 60018; telephone (847) 294-8112; 
email [email protected].
    (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.

 (h) Subject

    Joint Aircraft Service Component (JASC) Code: 6200 Main Rotor 
System.

 (i) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference 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) Enstrom Service Directive Bulletin No. 0127, Revision 1, 
dated October 6, 2017.
    (ii) Enstrom Service Directive Bulletin No. T-058, dated August 
2, 2017.
    (3) For Enstrom 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 
www.enstromhelicopter.com.
    (4) You may view this service information at FAA, Office of the 
Regional Counsel, Southwest Region, 10101 Hillwood Pkwy, Room 6N-
321, Fort Worth, TX 76177. For information on the availability of 
this material at the FAA, call (817) 222-5110.
    (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: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Fort Worth, Texas, on December 11, 2017.
Scott A. Horn,
Deputy Director for Regulatory Operations, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2017-27268 Filed 12-19-17; 8:45 am]
 BILLING CODE 4910-13-P