Airworthiness Directives; Bell Textron Canada Limited Helicopters

[Federal Register Volume 86, Number 237 (Tuesday, December 14, 2021)]
[Rules and Regulations]
[Pages 70966-70969]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-27012]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0830; Project Identifier AD-2020-00257-R; 
Amendment 39-21836; AD 2021-24-15]
RIN 2120-AA64


Airworthiness Directives; Bell Textron Canada Limited Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
Bell Textron Canada Limited Model 206L-1, 206L-3, and 206L-4 
helicopters with certain Air Comm Corporation air conditioning systems 
installed. This AD was prompted by reports of damage to the drive ring 
spline teeth and the mating spline teeth. This AD requires visually 
inspecting the drive ring spline teeth and the mating area spline teeth 
on the oil cooler blower shaft for signs of deformation and fretting 
and depending on the results of the inspection, removing certain parts 
from service. This AD also requires reinstalling certain parts, 
applying torque, and aligning certain bolt holes. The FAA is issuing 
this AD to address the unsafe condition on these products.

DATES: This AD is effective January 18, 2022.
    The Director of the Federal Register approved the incorporation by 
reference of a certain document listed in this AD as of January 18, 
2022.

ADDRESSES: For service information identified in this final rule, 
contact Air Comm Corporation, 1575 Westminster, CO 80234; telephone 
(303) 440-4075; or at https://www.aircommcorp.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 information on the availability of this material 
at the FAA, call (817) 222-5110. It is also available at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-
0830.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0830; 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 final rule, any 
referenced service

[[Page 70967]]

information, any comments received, and other information. The street 
address for Docket Operations is U.S. Department of Transportation, 
Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 
New Jersey Avenue SE, Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Matthew Bryant, Aerospace Engineer, 
Denver ACO Branch, FAA, 26805 East 68th Avenue, Denver, CO 80249; 
telephone (303) 342-1080; email [email protected].

SUPPLEMENTARY INFORMATION:

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to Bell Textron Canada 
Limited Model 206L-1, Model 206L-3, and Model 206L-4 helicopters with 
certain Air Comm Corporation air conditioning systems installed. The 
NPRM published in the Federal Register on September 24, 2021 (86 FR 
53015). In the NPRM, the FAA proposed to require within 300 hours time-
in-service (TIS), and thereafter at intervals not to exceed 300 hours 
TIS, gaining access to the drive ring spline teeth and the mating area 
spline teeth on the oil cooler blower shaft, repetitively inspecting 
the drive ring spline teeth and the mating spline teeth on the tail 
rotor drive's oil cooler blower shaft for deformation and fretting, and 
depending on the results of each inspection, removing certain parts 
from service before further flight. The NPRM also proposed to require 
reinstalling certain parts, and if required, reinstalling the drive 
pulley by torqueing and aligning the drive pulley bolt holes.
    The FAA issued Special Airworthiness Information Bulletin SW-19-05 
on April 4, 2019 (SAIB SW-19-05), to alert owners and operators of Bell 
Textron Canada Limited Model 206L-1, 206L-3, and 206L-4 helicopters 
with Air Comm Corporation's Supplemental Type Certificate (STC) 
SH2750NM installed. SAIB SW-19-05 was prompted by reports of the air 
conditioner pulley's locking system, which is installed on the oil 
cooler drive shaft's splined quill, causing excessive spline tooth wear 
to the drive ring spline teeth and the mating spline teeth on the oil 
cooler blower shaft. SAIB SW-19-05 recommends following the inspection 
instructions of certain Air Comm Corporation service information and 
routinely inspecting the air conditioner pulley lock ring.
    At the time SAIB SW-19-05 was issued, the airworthiness concern was 
not determined to be an unsafe condition that would warrant AD action 
under 14 CFR part 39. However, subsequent investigations were not able 
to determine whether the limited damaged observed on several oil cooler 
blower shafts would remain localized or progress to a point where the 
shaft is no longer safe for continued use. The FAA also later 
determined that operators may have difficulty aligning the air 
conditioning system's drive ring holes with the air conditioning 
condenser drive pulley without leaving the condenser drive pulley 
under-torqued. This condition, if not addressed, could result in a 
failure of the oil cooler blower shaft, which could lead to loss of 
tail rotor authority and subsequent loss of helicopter control.
    Accordingly, the FAA is issuing this AD for Bell Textron Canada 
Limited Model 206L-1 and 206L-3 helicopters with Bell Model 206L1/L3 
Service Instruction for Increased Gross Weight Upgrade Kit BHT-206-SI-
2052, Revision 1, dated October 14, 2010, installed and Bell Model 
206L-4 helicopters equipped with one of the following Air Comm 
Corporation STC SH2750NM air conditioning systems part number; 206EC-
204-1, 206EC-204-2, 206EC-208-1, 206EC-208-2, 206EC-210-1, 206EC-210-2, 
206EC-210-3, 206EC-212-3 or 206EC-212-4. Helicopters with a 206L-1+ 
designation are Model 206L-1 helicopters and helicopters with a 206L-3+ 
designation are Model 206L-3 helicopters.

Discussion of Final Airworthiness Directive

Comments

    The FAA received no comments on the NPRM or on the determination of 
the costs.

Conclusion

    The FAA reviewed the relevant data and determined that air safety 
requires adopting this AD as proposed except for minor editorial 
changes. Accordingly, the FAA is issuing this AD to address the unsafe 
condition on these helicopters.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed ACC Air Comm Corporation Service Bulletin SB 
206EC-091119, Rev B, dated May 26, 2021 (SB 206EC-091119 Rev B), which 
specifies procedures for visually inspecting the drive ring spline 
teeth and the mating spline teeth on the tail rotor drive's oil cooler 
blower shaft for deformation or fretting.
    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.

Differences Between This AD and the Service Bulletin

    SB 206EC-091119 Rev B requires inspecting the air conditioning 
compressor drive belt tension and the general condition of the drive 
belt, drive pulley, and surrounding components, whereas this AD does 
not. SB 206EC-091119 Rev B requires reporting any deformation or 
fretting to Air Comm Corporation Service Department, whereas this AD 
does not. SB 206EC-091119 Rev B provides an option to deactivate the 
air conditioning system if deformation or fretting is found on the 
drive ring or the oil cooler blower shaft assembly, whereas this AD 
requires removing these parts from service instead.

Costs of Compliance

    The FAA estimates that this AD affects up to 100 helicopters of 
U.S. Registry. Labor rates are estimated at $85 per work-hour. Based on 
these numbers, the FAA estimates the following costs to comply with 
this AD.
    Removing the tail rotor drive system's forward short shaft, spline 
adaptor, and drive ring and visually inspecting the drive ring spline 
teeth and the mating area spline teeth take about 1 work-hour for an 
estimated cost of $85 per helicopter and $8,500 for the U.S. fleet per 
inspection cycle.
    Replacing the drive ring takes about 3 work-hours and parts cost 
about $300 for an estimated cost of $555 per replacement.
    Replacing the oil cooler blower assembly takes about 3 work-hours 
and parts cost about $2,720 for an estimated cost of $2,975 per 
replacement.
    Aligning each bolt hole and re-torqueing the drive pulley take 
about 0.5 work-hours for an estimated cost of $43 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

[[Page 70968]]

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

    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 responsibilities among the various 
levels of government.
    For the reasons discussed above, I certify that this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Will not affect intrastate aviation in Alaska, 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 
reference, Safety.

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:

2021-24-15 Bell Textron Canada Limited: Amendment 39-21836; Docket 
No. FAA-2021-0830; Project Identifier AD-2020-00257-R.

(a) Effective Date

    This airworthiness directive (AD) is effective January 18, 2022.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to the Bell Textron Canada Limited helicopters 
identified in paragraphs (c)(1) and (2) of this AD:
    (1) Model 206L-1 and Model 206L-3 helicopters, certificated in 
any category, with Bell Model 206L1/L3 Service Instruction for 
Increased Gross Weight Upgrade Kit BHT-206-SI-2052, Revision 1, 
dated October 14, 2010, installed and that are equipped with one of 
the following Air Comm Corporation Supplemental Type Certificate 
(STC) SH2750NM air conditioning systems part number (P/N) 206EC-204-
1, 206EC-204-2, 206EC-208-1, 206EC-208-2, 206EC-210-1, 206EC-210-2, 
206EC-210-3, 206EC-212-3, or 206EC-212-4; and

    Note 1 to paragraph (c)(1) of this AD: Helicopters with a 206L-
1+ designation are Model 206L-1 helicopters and helicopters with a 
206L-3+ designation are Model 206L-3 helicopters.

    (2) Model 206 L-4 helicopters, certificated in any category, and 
that are equipped with one of the following Air Comm Corporation STC 
SH2750NM air conditioning systems P/N 206EC-204-1, 206EC-204-2, 
206EC-208-1, 206EC-208-2, 206EC-210-1, 206EC-210-2, 206EC-210-3, 
206EC-212-3, or 206EC-212-4.

(d) Subject

    Joint Aircraft Service Component (JASC) Code: 6510, Tail Rotor 
Drive Shaft.

(e) Unsafe Condition

    This AD was prompted by reports of deformation or fretting of 
the spline teeth on the air conditioning system drive ring and on 
the oil cooler blower shaft. The FAA is issuing this AD to detect 
deformation and fretting. The unsafe condition, if not addressed, 
could result in a failure of the oil cooler blower shaft, which 
could lead to loss of tail rotor authority and subsequent loss of 
helicopter control.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Required Actions

    Within 300 hours time-in-service (TIS) after the effective date 
of this AD, and thereafter at intervals not to exceed 300 hours TIS:
    (1) Gain access to the drive ring spline teeth and the mating 
area spline teeth on the oil cooler blower shaft by removing the 
tail rotor drive system's forward short shaft and spline adaptor, 
and the air conditioner system's drive ring. Refer to Figure 1 of 
ACC Air Comm Corporation Service Bulletin SB 206EC-091119, Rev B, 
dated May 26, 2021 for a depiction of each component's location.
    (2) Visually inspect the drive ring spline teeth and the mating 
area spline teeth on the oil cooler blower shaft for deformation and 
fretting.
    (i) If there is deformation or fretting on the drive ring spline 
teeth, before further flight, remove the drive ring from service and 
replace it with an airworthy part.
    (ii) If there is deformation or fretting on the mating area 
spline teeth of the oil cooler blower shaft, before further flight, 
remove the oil cooler blower assembly from service and replace with 
an airworthy part.
    (3) Reinstall the drive ring, spline adapter, and the forward 
short shaft. If the compressor drive pulley was removed, torque the 
drive pulley to 200-300 in-lbs, increasing torque in this range to 
align the four threaded holes with the through holes in the drive 
ring. Do not back-off torque to align the bolt holes.

(h) Special Flight Permits

    Special flight permits are prohibited.

(i) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Denver ACO, FAA, has the authority to approve 
AMOCs for this AD, if requested using the procedures found in 14 CFR 
39.19. In accordance with 14 CFR 39.19, send your request to your 
principal inspector or local Flight Standards District Office, as 
appropriate. If sending information directly to the manager of the 
Denver ACO, send it to the attention of the person identified in 
paragraph (j)(1) of this AD. Information may be emailed to: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(j) Related Information

    (1) For more information about this AD, contact Matthew Bryant, 
Aerospace Engineer, Denver ACO Branch, FAA, 26805 East 68th Avenue, 
Denver, CO 80249; telephone (303) 342-1092; email [email protected].
    (2) Service information identified in this AD, is available at 
the contact information specified in paragraphs (k)(3) and (4) of 
this AD.

(k) 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) ACC Air Comm Corporation Service Bulletin SB 206EC-091119, 
Rev B, dated May 26, 2021.
    (ii) [Reserved]
    (3) For service information identified in this AD, contact Air 
Comm Corporation, 1575 W 124th Ave. #210, Westminster, CO 80234; 
telephone: (303) 440-4075; email [email protected].
    (4) You may view this service information at the 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, email: [email protected], or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.


[[Page 70969]]


    Issued on November 19, 2021.
Ross Landes,
Deputy Director for Regulatory Operations, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-27012 Filed 12-13-21; 8:45 am]
BILLING CODE 4910-13-P

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