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Federal Register / Vol. 86, No. 121 / Monday, June 28, 2021 / Proposed Rules marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this NPRM. Submissions containing CBI
should be sent to Darren Gassetto, Aerospace Engineer, COS Program Management Section, FAA, Operational Safety Branch, Compliance &
Airworthiness Division, 1600 Stewart Avenue, Suite 410, Westbury, NY
11590; telephone 516 2287323; email Darren.Gassetto@faa.gov. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking.
Background Transport Canada Civil Aviation TCCA, which is the aviation authority for Canada, has issued Canadian AD
CF201835, dated December 19, 2018
Canadian AD CF201835, to correct an unsafe condition for Bell Textron Canada Limited Model 429 helicopters.
Transport Canada advises that there have been reports of tail rotor gearbox assemblies found loose on the gearbox support. Transport Canada issued Emergency Canadian Airworthiness Directive CF201818, dated July 11, 2018, which corresponds to FAA AD
20181651, Amendment 3919421 83
FR 53171, October 22, 2018, to address the immediate safety concern. An ongoing investigation determined that
this condition-loose tail rotor gearbox assemblies-could return even after the corrective actions by the previous AD
have been completed. This condition, if not addressed, could result in structural damage and possible loss of control of the helicopter.
Accordingly, Canadian AD CF2018
35 requires repetitive torque checks of the tail rotor gearbox attachment hardware and corrective actions if necessary. The corrective action is doing additional repetitive torque checks at intervals of 10 to 25 hours air time until the torque stabilizes on all the nuts.
FAAs Determination The helicopter has been approved by the aviation authority of Canada and is approved for operation in the United States. Pursuant to the FAAs bilateral agreement with Canada, Transport Canada, its technical representative, has notified the FAA of the unsafe condition described in its AD. The FAA is proposing this AD after evaluating all known relevant information and determining that the unsafe condition described previously is likely to exist or develop on other helicopters of the same type design.
Related Service Information Under 1
CFR Part 51
The FAA reviewed Bell Alert Service Bulletin 4291841, dated July 24, 2018.

This service information specifies procedures for repetitive torque checks of the tail rotor gearbox attachment hardware.
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.
Proposed AD Requirements in This NPRM
This proposed AD would require accomplishing the actions specified in the service information already described, except as discussed under Differences Between this Proposed AD
and the Transport Canada AD.
Differences Between This Proposed AD
and the Transport Canada AD
Where Canadian AD CF201835
refers to 200-hour inspections and 10 to 25 hours air time for the torque checks, for this proposed AD use timein-service instead.
Costs of Compliance The FAA estimates that this AD, if adopted as proposed, would affect 98
helicopters of U.S. Registry. The FAA
estimates the following costs to comply with this proposed AD:

ESTIMATED COSTS FOR REQUIRED ACTIONS
Action
Labor cost
Torque check

1 work-hour $85 per hour = $85

The FAA estimates the following costs to do any necessary on-condition actions that would be required based on
Cost per product
Parts cost
the results of any required actions. The FAA has no way of determining the
$0

Cost on U.S.
operators
$85

$8,330

number of helicopters that might need these on-condition actions:

ESTIMATED COSTS OF ON-CONDITION ACTIONS
Action
Labor cost
Repetitive torque check

1 work-hour $85 per hour = $85, per cycle

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Authority for This Rulemaking Title 49 of the United States Code specifies the FAAs 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 Agencys authority.
The FAA is issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701: General requirements. Under
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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.

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Parts cost
Cost per product $0

$85, per cycle.

Regulatory Findings 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:

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