DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2018-0334; Product Identifier 2017-SW-133-AD]
Airworthiness Directives; Bell Helicopter Textron Canada Limited
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
SUMMARY: The FAA proposes to adopt a new airworthiness directive
for Bell Helicopter Textron Canada Limited (BHTC) Model 429
helicopters. This proposed AD would require repetitive inspections of
certain cyclic and collective assembly bearings. This proposed AD is
prompted by reports that precipitation can lead to reduced
effectiveness of the grease in the bearings. The actions of this
proposed AD are intended to address an unsafe condition on these
DATES: The FAA must receive comments on this proposed AD by May
ADDRESSES: You may send comments by any of the following methods:
Federal eRulemaking Docket: Go to https://www.regulations.gov. Follow
online instructions for sending your comments electronically.
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 https://www.regulations.
gov by searching for and locating Docket No. FAA-2018-0334;
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 proposed AD, the Transport Canada Civil Aviation
(Transport Canada) AD, any comments received, and other information.
The street address for the Docket Operations Office is listed above.
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 https://www.bellcustomer.com. You may view 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: David Hatfield, Aviation Safety
Engineer, Safety Management Section, Rotorcraft Standards Branch, FAA,
10101 Hillwood Pkwy, Fort Worth, TX 76177; telephone 817-222-5110;
The FAA invites you to participate in this rulemaking by submitting
written comments, data, or views. The FAA also invites 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
The FAA will file in the docket all comments received, as well as a
report summarizing each substantive public contact with FAA personnel
concerning this proposed rulemaking. Before acting on this proposal,
the FAA will consider all comments received on or before the closing
date for comments. The FAA will consider comments filed after the
comment period has closed if it is possible to do so without incurring
expense or delay. The FAA may change this proposal in light of the
Transport Canada, which is the aviation authority for Canada, has
issued Canadian AD No. CF-2016-11R2, dated October 18, 2017, to correct
an unsafe condition for BHTC Model 429 helicopters equipped with a
bellcrank assembly part number (P/N) 429-001-523-101, 429-001-523-103,
429-001-532-101 or 429-001-532-103.
Transport Canada advises that in-service reports show that bearings
in the roof-mounted flight control bellcranks are adversely affected by
precipitation. Pooling can occur at the forward portion of the roof,
providing a source of contamination for bearings in the roof-mounted
flight controls. Precipitation may reduce the effectiveness of the
grease in the bearings, allowing corrosion to occur, and resulting in
intermittent restrictions, such as binding and roughness in the flight
controls, Transport Canada advises. Transport Canada also advises that
an undetected corroded bearing could lead to restrictions in the
collective, directional, or pitch control systems, resulting in
difficulty controlling the helicopter.
Transport Canada consequently requires within 12 months after the
helicopter was manufactured and thereafter at intervals not to exceed
months, inspecting the flight controls and replacing any discrepant
bearings. If the helicopter's age exceeds 12 months, Transport Canada
requires the 12-month inspection within 30 days. Transport Canada also
requires, within 30 days, performing a functional check and
replacement, if applicable, of the bearings if the most recent
functional check of the helicopter was performed with the alternate
procedure of using a hydraulic test stand or if the inspection method
These helicopters have been approved by the aviation authority of
Canada and are approved for operation in the United States. Pursuant
the FAA's bilateral agreement with Canada, Transport Canada, its
technical representative, has notified the FAA about the unsafe
condition described in its AD. The FAA is proposing this AD after
evaluating all known relevant information and determining that an
unsafe condition is likely to exist or develop on other products of the
same type design.
Related Service Information
The FAA reviewed Bell Helicopter Alert Service Bulletin 429-15-21,
Revision B, dated May 11, 2017 (ASB), which specifies moving the cyclic
stick fore, aft, and laterally, and the collective stick up and down
from stop to stop to detect deteriorated pivot bearings. The ASB also
specifies inspecting to determine whether the bearings in the
collective, lateral, and longitudinal arm assemblies rotate freely. If
discrepant arm bearings are found, the ASB specifies contacting BHTC
Product Support Engineering to report the findings and replacing the
discrepant parts with serviceable parts.
Proposed AD Requirements
This proposed AD would require within 12 months after the
helicopter was manufactured or 30 days after the effective date of this
AD, whichever occurs later, and thereafter at intervals not to exceed
Disconnecting the forward ends of the collective control
tube, longitudinal stability and control augmentation system (SCAS)
actuator, and lateral SCAS actuator and stowing the collective control
tube and each SCAS actuator to prevent binding.
Slowly moving the cyclic fore/aft and laterally, and the
collective up/down from stop to stop to determine if there is any
roughness. If there is any roughness in the flight control system,
before further flight, replace the six pivot bearings in the
collective/lateral bellcrank assembly and the longitudinal bellcrank
Inspecting each arm end bearing at the end of the
collective, lateral, and longitudinal arm assemblies by rotating each
bearing and ensuring each bearing rotates freely. If there is any
binding in any arm end bearing or on the longitudinal bellcrank
assembly, before further flight, replace each arm end bearing.
Differences Between This Proposed AD and the Transport Canada AD
Transport Canada provides requirements if the most recent
functional procedure was performed using a hydraulic test stand as an
alternate procedure. This AD provides no such alternate procedure.
The FAA considers this proposed AD to be an interim action. If
final action is later identified, the FAA might consider further
Costs of Compliance
The FAA estimates that this proposed AD would affect 64 helicopters
of U.S. Registry and that labor costs average $85 per work-hour. Based
on these estimates, the FAA expects the following costs:
Inspecting the cyclic and the collective for roughness
would require 3 work-hours and no parts for a total cost of $255 per
helicopter, and $16,320 for the U.S. fleet.
Replacing six pivot bearings would require 3 work-hours
for a labor cost of $255. Parts would cost $624 for a total cost of
$879 per helicopter.
Replacing 3 arm end bearings would require 3 work-hours
for a labor cost of $255. Parts would cost $135 for a total cost of
$390 per helicopter.
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.
The FAA is 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.
The FAA 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
2. Will not affect intrastate aviation in Alaska to the extent that
it justifies making a regulatory distinction; and
3. 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.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
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