[Federal Register Volume 83, Number 96 (Thursday, May 17, 2018)]
[Proposed Rules]
[Pages 22886-22888]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-10494]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0438; Product Identifier 2017-SW-062-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for 
Airbus Helicopters Model AS355E, AS355F, AS355F1, AS355F2, and AS355N 
helicopters. This proposed AD would require measuring a vibration level 
in the tail rotor (T/R) drive. This proposed AD is prompted by reports 
of bearing degradation. The actions of this proposed AD are intended to 
prevent an unsafe condition on these helicopters.

DATES: We must receive comments on this proposed AD by July 16, 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-2018-
0438; or in person at Docket Operations between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays. The AD docket contains 
this proposed AD, the European Aviation Safety Agency (EASA) AD, the 
economic evaluation, any comments received, and other information. The 
street address for Docket Operations (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 proposed rule, contact 
Airbus Helicopters, 2701 N. Forum Drive, Grand Prairie, TX 75052; 
telephone (972) 641-0000 or (800) 232-0323; fax (972) 641-3775; or at 
http://www.helicopters.airbus.com/website/en/ref/Technical-Support_73.html. 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.

FOR FURTHER INFORMATION CONTACT: Rao Edupuganti, Aviation Safety 
Engineer, Regulations and Policy Section, Rotorcraft Standards Branch, 
FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone (817) 222-
5110; email [email protected].

SUPPLEMENTARY INFORMATION: 

Comments Invited

    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 might 
result from adopting the proposals in this document. The most helpful 
comments reference a specific portion of the proposal, 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 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 proposed rulemaking. Before acting on this proposal, we 
will consider all comments we receive on or before the closing date for 
comments. We will consider comments filed after the comment period has 
closed if it is possible to do so without incurring expense or delay. 
We may change this proposal in light of the comments we receive.

Discussion

    EASA, which is the Technical Agent for the Member States of the 
European Union, has issued EASA AD No. 2017-0159, dated August 25, 
2017, to correct an unsafe condition for Airbus Helicopters Model 
AS355E, AS355F, AS355F1, AS355F2, and AS355N helicopters. EASA advises 
of two occurrences on AS355 military helicopters in which the main 
gearbox (MGB) oil cooler fan bearing (bearing) installed on the TR 
drive shaft experienced significant degradation. EASA states that while 
investigation has not determined the cause of the failures, this 
condition may also occur on other AS355 helicopters due to design 
commonality. According to EASA, this condition, if not detected and 
corrected, could result in loss of MGB and engine oil cooling function, 
loss of the rear transmission, and subsequent loss of control of the 
helicopter. To address this unsafe condition and as an interim measure, 
the EASA AD requires two vibration level measurements of the forward 
portion of the tail rotor drive line, one before and one after cleaning 
the MGB oil cooler fan, and replacing the bearings if excessive level 
or level trends are detected. The EASA AD also specifies that after the 
effective date of the AD, only those MGB oil cooler fan assembly 
bearings that are new or that have passed the vibration level 
measurements may be installed.

FAA's Determination

    These helicopters have been approved by the aviation authority of 
France and are approved for operation in the United States. Pursuant to 
our bilateral agreement with France, EASA, its technical 
representative, has notified us of the unsafe condition described in 
its AD. We are proposing this AD because we evaluated all known 
relevant information and determined that an unsafe condition is likely 
to exist or develop on other products of the same type design.

Related Service Information

    We reviewed Airbus Helicopters Alert Service Bulletin No. AS355-
05.00.77, Revision 0, dated July 3, 2017, which contains procedures for 
checking the condition of the fan assembly bearings by measuring the 
vibration levels of the first section of the T/R drive.

[[Page 22887]]

Proposed AD Requirements

    This proposed AD would require, within 165 hours time-in-service, 
measuring the T/R drive vibration level without balancing, cleaning the 
fan, and repeating the vibration level measurement. If the difference 
between the two amplitude values is greater than 0.75 inch per second 
(ips), the proposed AD would require, before further flight, replacing 
each T/R fan bearing.

Interim Action

    We consider this proposed AD to be an interim action. The 
manufacturer is currently developing a terminating action for the 
unsafe condition described in this proposed AD. If a terminating action 
is identified, we may consider further rulemaking then.

Costs of Compliance

    We estimate that this proposed AD would affect 104 helicopters of 
U.S. Registry.
    We estimate that operators may incur the following costs in order 
to comply with this AD. At an average labor rate of $85 per work-hour, 
measuring the vibration levels would require about 5 work-hours, for a 
cost of $425 per helicopter and $44,200 for the U.S. operator fleet. If 
required, replacing both fan assembly bearings would require about 8 
work-hours, and required parts would cost $1,064, for a cost per 
helicopter of $1,744.

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 proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 this proposed regulation:
    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 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 proposed 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.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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):

Airbus Helicopters: Docket No. FAA-2018-0438; Product Identifier 
2017-SW-062-AD.

(a) Applicability

    This AD applies to Airbus Helicopters Model AS355E, AS355F, 
AS355F1, AS355F2, and AS355N helicopters, certificated in any 
category.

(b) Unsafe Condition

    This AD defines the unsafe condition as degradation of a main 
gearbox (MGB) oil cooler fan assembly bearing. This condition could 
result in loss of MGB and engine oil cooling function, loss of the 
rear transmission, and subsequent loss of control of the helicopter.

(c) Comments Due Date

    We must receive comments by July 16, 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 165 hours time-in-service (TIS):
    (i) Measure the tail rotor (T/R) drive vibration level without 
balancing the T/R drive, and record the amplitude value.
    (ii) Clean the oil cooler fan.
    (iii) Measure the T/R drive vibration level without balancing 
the T/R drive, and record the amplitude value.
    (iv) Calculate the difference between the two amplitude values. 
If the difference is greater than 0.75 inch per second (ips), before 
further flight, replace each oil cooler fan assembly bearing.
    (2) After the effective date of this AD, do not install an oil 
cooler fan assembly bearing with more than 0 hours TIS unless the 
requirements of this AD have been accomplished.

(f) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Safety Management Section, Rotorcraft Standards 
Branch, FAA, may approve AMOCs for this AD. Send your proposal to: 
Rao Edupuganti, Aviation Safety Engineer, Regulations and Policy 
Section, Rotorcraft Standards Branch, FAA, 10101 Hillwood Pkwy., 
Fort Worth, TX 76177; telephone (817) 222-5110; 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.

(g) Additional Information

    (1) Airbus Helicopters Alert Service Bulletin No. AS355-
05.00.77, Revision 0, dated July 3, 2017, which is not incorporated 
by reference, contains additional information about the subject of 
this AD. For service information identified in this AD, contact 
Airbus Helicopters, 2701 N. Forum Drive, Grand Prairie, TX 75052; 
telephone (972) 641-0000 or (800) 232-0323; fax (972) 641-3775; or 
at http://www.helicopters.airbus.com/website/en/ref/Technical-Support_73.html. 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.
    (2) The subject of this AD is addressed in European Aviation 
Safety Agency (EASA) AD No. 2017-0159, dated August 25, 2017. You 
may view the EASA AD on the internet at http://www.regulations.gov 
in the AD Docket.

 (h) Subject

    Joint Aircraft Service Component (JASC) Code: 6510 Tail Rotor 
Driveshaft.



[[Page 22888]]


    Issued in Fort Worth, Texas, on May 7, 2018.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2018-10494 Filed 5-16-18; 8:45 am]
 BILLING CODE 4910-13-P


