DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0647; Product Identifier 2017-SW-083-AD]
RIN 2120-AA64

Airworthiness Directives; Bell Helicopter Textron Canada Limited
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
Bell Helicopter Textron Canada Limited (Bell) Model 429 helicopters.
This proposed AD would revise the life limit for the nose landing gear
(NLG) assembly. This proposed AD is prompted by revised airworthiness
limitations determined by Bell. 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 September 17, 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-
0647; 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 Transport Canada 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
Bell Helicopter Textron Canada Limited, 12,800 Rue de l'Avenir,
Mirabel, Quebec J7J1R4; telephone (450) 437-2862 or (800) 363-8023; fax
(450) 433-0272; or at http://www.bellcustomer.com/files/. 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: Matt Fuller, Senior Aviation Safety
Engineer, Safety Management Section, Rotorcraft Standards Branch, FAA,
10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone (817) 222-5110;
email matthew.fuller@faa.gov.

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

Transport Canada, which is the aviation authority for Canada, has
issued Canadian AD No. CF-2016-07, dated March 4, 2016, to correct an
unsafe condition for Bell Model 429 helicopters with wheeled landing
gear. Transport Canada advises that Bell has replaced the airworthiness
limitations for the NLG main fitting to bell crank bolt part number (P/
N) M084-20H125-101 and NLG main fitting P/N M084-20H011-107 with an
airworthiness limitation for the next higher assembly, NLG assembly P/N
429-336-100-101. According to Transport Canada, the NLG assembly's life
limit is reduced to 50,000 retirement index number (RIN) or 4,500 hours
time-in-service (TIS). Transport Canada advises that failure to replace
components prior to established airworthiness limitations could result
in an unsafe condition.

FAA's Determination

These helicopters have been approved by the aviation authority of
Canada and are approved for operation in the United States. Pursuant to
our bilateral agreement with Canada, Transport Canada, 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 helicopters of the same type design.

Related Service Information

We reviewed Bell Alert Service Bulletin No. 429-15-24, Revision A,
dated September 23, 2015, which specifies updating the Bell 429
maintenance manual with Revision 24 to incorporate the revised
airworthiness limitations for the NLG assembly, NLG main fitting to
bellcrank bolt, and the NLG main fitting.

Proposed AD Requirements

This proposed AD would revise the life limit of the NLG assembly by
requiring, before further flight, removing from service any NLG
assembly P/N 429-336-100-101 that has reached or exceeded 4,500 hours
TIS or 50,000 RIN. Thereafter, this proposed AD would require removing
from service each NLG assembly P/N 429-336-100-101 before it
accumulates 4,500 hours TIS or 50,000 RIN, whichever occurs first.

Differences Between This Proposed AD and the Transport Canada AD

The Transport Canada AD applies to certain serial-numbered
helicopters, whereas this proposed AD would apply to all Bell Model 429
helicopters with the affected NLG assembly installed.

Costs of Compliance

We estimate that this proposed AD would affect less than 75
helicopters of U.S. Registry (as this proposed AD would not apply to
Bell Model 429 helicopters with skid landing gear). At an average labor
rate of $85 per hour, replacing a NLG assembly would require 10 work-
hours, and required parts would cost $104,648, for a cost of $105,498
per helicopter and up to $7,912,350 for the U.S. fleet.

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

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]

2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive (AD):