[Federal Register Volume 86, Number 101 (Thursday, May 27, 2021)]
[Rules and Regulations]
[Pages 28473-28476]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-11081]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-26107; Project Identifier 2004-SW-30-AD; Amendment 
39-21549; AD 2021-10-16]
RIN 2120-AA64


Airworthiness Directives; Carson Helicopters, Inc.; Croman 
Corporation; Sikorsky Aircraft Corporation; and Siller 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 all 
Carson Helicopters, Inc., Model S-61L and SH-3H helicopters; Croman 
Corporation Model SH-3H helicopters; Sikorsky Aircraft Corporation 
Model S-61A, S-61D, S-61E, and S-61V helicopters; and Siller 
Helicopters Model CH-3E and SH-3A helicopters. This AD was prompted by 
an accident. This AD requires tracking hours time-in-service (TIS) and 
external lift cycles (lift cycles) for certain main gearbox left and 
right input freewheel unit (IFWU) assemblies. This AD also requires 
determining the type of IFWU assembly installed and depending on the 
results, calculating the moving average, repetitive inspections, 
recording certain information, replacing parts, and marking parts. The 
FAA is issuing this AD to address the unsafe condition on these 
products.

DATES: This AD is effective July 1, 2021.

[[Page 28474]]

    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of July 1, 
2021.

ADDRESSES: For service information identified in this final rule, 
contact your local Sikorsky Field Representative or Sikorsky's Service 
Engineering Group at Sikorsky Aircraft Corporation, 124 Quarry Road, 
Trumbull, CT 06611; telephone 1-800-Winged-S; email 
[email protected]. Operators may also log on to the 
Sikorsky 360 website at https://www.sikorsky360.com. 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. It is also available at https://www.regulations.gov by searching for and locating Docket No. FAA-2006-
26107.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2006-26107; 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 
comments received, and other information. The 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: Isabel Saltzman, Aviation Safety 
Engineer, Boston ACO Branch, FAA, 1200 District Avenue, Burlington, MA 
01803; telephone 781-238-7649; 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 all Sikorsky Aircraft 
Corporation Model S-61 A, D, E, and V helicopters; Croman Corporation 
Model SH-3H helicopters, Carson Helicopters, Inc. Model S-61L 
helicopters; and Siller Helicopters Model CH-3E and SH-3A helicopters. 
The NPRM published in the Federal Register on October 30, 2006 (71 FR 
63272). The NPRM was prompted by an accident in which the left and 
right IFWU assembly on a helicopter slipped or disengaged resulting in 
both engines overspeeding, engine shutdowns, and loss of engine power 
to the transmissions. In the NPRM, the FAA proposed to require creating 
a component history card or equivalent record and recording the hours 
TIS and the lift cycles for each affected main gearbox left and right 
IFWU assembly. The NPRM also proposed to require determining if the 
IFWU assembly is a repetitive external lift (REL) or non-REL IFWU 
assembly. The determination includes calculating a moving average of 
lift cycles per hour TIS at specified intervals on each IFWU assembly. 
For REL IFWU assemblies, the NPRM proposed to require repetitive 
inspections, which include visual and dimensional inspections, of the 
IFWU assembly for wear, surface distress, and endplay, recording 
certain information, and replacing affected parts with an airworthy 
part. In addition, the NPRM proposed to require permanently marking the 
REL IFWU camshafts and gear housings with the letters ``REL'' on the 
surface of these parts.
    The FAA issued a supplemental notice of proposed rulemaking (SNPRM) 
to amend 14 CFR part 39 by adding an AD that would apply to all Carson 
Helicopters, Inc., Model S-61L and SH-3H helicopters; Croman 
Corporation Model SH-3H helicopters; Sikorsky Aircraft Corporation 
Model S-61A, S-61D, S-61E, and S-61V helicopters; and Siller 
Helicopters Model CH-3E and SH-3A helicopters. The SNPRM published in 
the Federal Register on March 15, 2021 (86 FR 14285). The SNPRM was 
prompted by a determination that additional camshaft and gear housing 
part numbers need to be marked and the applicability and certain 
compliance times need clarification. The SNPRM proposed to require the 
same actions specified in the NPRM. The SNPRM also proposed to mark 
additional camshaft and gear housing part numbers. Additionally, the 
SNPRM clarified the applicability and certain compliance times. The FAA 
is issuing this AD to address the unsafe condition on these products.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from one commenter. The commenter was 
Croman Corp. The commenter supported the SNPRM without change.

Conclusion

    The FAA reviewed the relevant data, considered the comments 
received, and determined that air safety requires adopting the AD as 
proposed. Accordingly, the FAA is issuing this AD to address the unsafe 
condition on these products. Except for minor editorial changes, this 
AD is adopted as proposed in the SNPRM.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Sikorsky Aircraft Corporation Alert Service 
Bulletin 61B35-67B, Revision B, dated August 11, 2003. This service 
information specifies, among other actions, procedures for inspections, 
which includes visual and dimensional inspections, of the IFWU assembly 
for wear, surface distress, and endplay, and for recording certain 
information. 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.

Other Related Service Information

    The FAA also reviewed Sikorsky Aircraft Corporation All Operators 
Letter (AOL) CCS-61-AOL-04-0005, dated May 18, 2004. This service 
information provides an example and additional information about 
tracking cycles and the moving average procedure.
    The FAA also reviewed Sikorsky Aircraft S-61L/N Overhaul Manual, 
SA4045-83, Revision 20, dated August 15, 2003, as revised by Temporary 
Revisions 65-193, -194, -195, and -196, which contains the overhaul 
procedures for the IFWU assembly.

Differences Between This AD and the Service Information

    The effectivity of Sikorsky Aircraft Corporation Alert Service 
Bulletin 61B35-67B, Revision B, dated August 11, 2003, includes Model 
S-61 L, N, NM, and R helicopters. However, for those helicopters, the 
unsafe condition is addressed in AD 2007-01-05, Amendment 39-14876 (72 
FR 1139, January 10, 2007). Therefore, those helicopters are not 
included in the applicability of this AD.
    Sikorsky Aircraft Corporation Alert Service Bulletin 61B35-67B, 
Revision B, dated August 11, 2003, specifies contacting Sikorsky and 
providing information to Sikorsky. This AD does not require you to 
contact Sikorsky or provide information to Sikorsky.

Costs of Compliance

    The FAA estimates that this AD affects 55 helicopters of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

[[Page 28475]]



                                                 Estimated Costs
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                                                                                                Cost on U.S.
            Action                 Labor cost          Parts cost       Cost per  product         operators
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Creating history card;          Up to 8 work-     Up to $1,975.......  Up to $2,655.......  Up to $146,025.
 determining type of IFWU        hours x $85 per
 assembly; inspecting IFWU       hour = $680.
 assemblies; recording
 information; replacing parts;
 and marking certain parts.
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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.

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:

2021-10-16 Carson Helicopters, Inc.; Croman Corporation; Sikorsky 
Aircraft Corporation; and Siller Helicopters: Amendment 39-21549; 
Docket No. FAA-2006-26107; Project Identifier 2004-SW-30-AD.

(a) Effective Date

    This airworthiness directive (AD) is effective July 1, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all helicopters identified in paragraphs 
(c)(1) through (6) of this AD, certificated in any category 
including restricted.
    (1) Carson Helicopters, Inc., Model S-61L helicopters.
    (2) Carson Helicopters, Inc., Model SH-3H helicopters.
    (3) Croman Corporation Model SH-3H helicopters.
    (4) Sikorsky Aircraft Corporation Model S-61A, S-61D, S-61E, and 
S-61V helicopters.
    (5) Siller Helicopters Model CH-3E helicopters.
    (6) Siller Helicopters Model SH-3A helicopters.

(d) Subject

    Joint Aircraft System Component (JASC) Code 6310, Engine/
Transmission Coupling.

(e) Unsafe Condition

    This AD was prompted by an accident in which the left and right 
input freewheel unit (IFWU) assembly on a helicopter slipped or 
disengaged, resulting in both engines overspeeding, engine 
shutdowns, and loss of engine power to the transmissions. The FAA is 
issuing this AD to address slipping of the main gearbox IFWU 
assembly, loss of engine power, and subsequent loss of control of 
the helicopter.

(f) Compliance

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

(g) Creation of History Card or Equivalent and Daily Actions

    Within 10 hours time-in-service (TIS) after the effective date 
of this AD, do the actions specified in paragraphs (g)(1) and (2) of 
this AD.
    (1) Create an external lift component history card or equivalent 
record for each IFWU assembly, part number (P/N) 61074-35000-041 
through 61074-35000-063 inclusive.
    (2) Count and, at the end of each day's operations, record the 
number of external lift cycles (lift cycles) performed and the hours 
TIS for each IFWU assembly, P/N 61074-35000-041 through 61074-35000-
063 inclusive. A ``lift cycle'' is defined as the lifting of an 
external load and subsequent release of the load. Record the lift 
cycles and hours TIS on the external lift component history card or 
equivalent record.

(h) Determination of IFWU Assembly Type and Calculations

    (1) Upon reaching 250 hours TIS after the effective date of this 
AD on each IFWU assembly, P/N 61074-35000-041 through 61074-35000-
063 inclusive, determine whether the IFWU assembly is a repetitive 
external lift (REL) or non-REL IFWU assembly by using a 250-hour TIS 
moving average. To perform the calculation, divide the total number 
of lift cycles performed during the first 250 hours TIS by 250. The 
result will be the first moving average calculation of lift cycles 
per hour TIS.
    (i) If the calculation specified in paragraph (h)(1) of this AD 
results in more than 6 lift cycles per hour TIS, the IFWU assembly 
is an REL IFWU assembly.
    (ii) If the calculation specified in paragraph (h)(1) of this AD 
results in 6 or less lift cycles per hour TIS, the IFWU assembly is 
a Non-REL IFWU assembly.
    (2) For each IFWU assembly determined to be a Non-REL IFWU 
assembly based on the first calculation of the 250-hour TIS moving 
average for lift cycles specified in paragraph (h)(1) of this AD: 
Within 50 hours TIS after the determination, and thereafter at 
intervals of 50 hours TIS, recalculate the average lift cycles per 
hour TIS to determine whether the IFWU assembly is an REL or non-REL 
IFWU assembly. To perform the calculation, subtract the total number 
of lift cycles performed during the first 50-hour TIS interval used 
in the previous moving average calculation from the total number of 
lift cycles performed on the IFWU assembly during the previous 300 
hours TIS. Divide this result by 250. The result will be the next or 
subsequent moving average calculation of lift cycles per hour TIS.
    (i) If any calculation specified in paragraph (h)(2) of this AD 
results in more than 6 lift

[[Page 28476]]

cycles per hour TIS, the IFWU assembly is an REL IFWU assembly.
    (ii) If any calculation specified in paragraph (h)(2) of this AD 
results in 6 or less lift cycles per hour TIS, the IFWU assembly is 
a Non-REL IFWU assembly.

    Note 1 to paragraph (h)(2): Sikorsky Aircraft Corporation All 
Operators Letter (AOL) CCS-61-AOL-04-0005, dated May 18, 2004, 
provides an example and additional information about tracking cycles 
and the moving average procedure.


    Note 2 to paragraph (h)(2): The following is a sample 
calculation for subsequent 50 hour TIS intervals. Assume the total 
number of lift cycles for the first 50 hour TIS interval used in the 
previous moving average calculation = 450 lift cycles and the total 
number of lift cycles for the previous 300 hours TIS = 2,700 lift 
cycles. The subsequent moving average of lift cycles per hour TIS = 
(2,700-450) divided by 250 = 9 lift cycles per hour TIS.

    (3) Once an IFWU assembly is determined to be an REL IFWU 
assembly, it remains an REL IFWU assembly for the rest of its 
service life and is subject to the inspection for REL IFWU 
assemblies required by paragraph (i) of this AD.
    (4) Once an IFWU assembly is determined to be an REL IFWU 
assembly, you no longer need to perform the 250-hour TIS moving 
average calculation required by paragraph (h)(2) of this AD, but you 
must continue to count and record the lift cycles as required by 
paragraph (g)(2) of this AD.

(i) Repetitive Inspections of REL IFWU Assemblies and Replacement

    For each REL IFWU assembly, as determined by paragraph (h)(1) or 
(2) of this AD:
    (1) Within 500 hours TIS or 7,500 lift cycles, whichever occurs 
first since the assembly was determined to be a REL IFWU assembly, 
and thereafter at intervals not to exceed 500 hours TIS or 7,500 
lift cycles, whichever occurs first, inspect for wear, surface 
distress, and endplay by following paragraphs B.(1) through B.(6) of 
the Accomplishment Instructions of Sikorsky Aircraft Corporation 
Alert Service Bulletin 61B35-67B, Revision B, dated August 11, 2003. 
Record all the information specified in Figures 1 through 3 of the 
Sikorsky Aircraft Corporation Alert Service Bulletin 61B35-67B, 
Revision B, dated August 11, 2003. You may record this information 
on any suitable maintenance record, or you may use the Sikorsky 
evaluation forms provided in Sikorsky Aircraft Corporation Alert 
Service Bulletin 61B35-67B, Revision B, dated August 11, 2003. This 
AD does not require you to contact Sikorsky or provide information 
to Sikorsky.
    (2) If during any inspection required by paragraph (i)(1) of 
this AD, any IFWU assembly part is found whose average wear, wear 
marks, surface distress, or endplay exceeds the limits specified in 
paragraphs B.(1) through B.(6) of the Accomplishment Instructions of 
Sikorsky Aircraft Corporation Alert Service Bulletin 61B35-67B, 
Revision B, dated August 11, 2003, before further flight, replace 
the affected part with an airworthy IFWU assembly part.

    Note 3 to paragraph (i)(2): Sikorsky Aircraft S-61L/N Overhaul 
Manual, SA4045-83, Revision 20, dated August 15, 2003, as revised by 
Temporary Revisions 65-193, -194, -195, and -196, contains the 
overhaul procedures for the IFWU assembly.

(j) Part Marking

    For each REL IFWU assembly, as determined by paragraph (h)(1) or 
(2) of this AD: Before further flight after the assembly was 
determined to be an REL IFWU assembly, permanently mark IFWU 
camshafts, P/N 61350-24052, 61350-24072, S6135-20611, S6135-20614 
and S6137-23075, and IFWU gear housings, P/N 61350-24051, 61350-
24068, S6135-20695, and S6137-23057, with the letters ``REL''. Mark 
the camshafts by applying etching ink on the surface of the part 
that is 0.5-inch square with the depth of the letters not to exceed 
0.001 inch. Before further flight and after etching, neutralize the 
etched surface and oil to prevent corrosion.

(k) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, International Validation Branch, 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 International Validation Branch, send 
it to the attention of the person identified in paragraph (l)(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.

(l) Related Information

    (1) For more information about this AD, contact Isabel Saltzman, 
Aviation Safety Engineer, Boston ACO Branch, FAA, 1200 District 
Avenue, Burlington, MA 01803; telephone 781-238-7649; email 
[email protected].
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (m)(3) and (4) of this AD.

(m) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) 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) Sikorsky Aircraft Corporation Alert Service Bulletin 61B35-
67B, Revision B, dated August 11, 2003.
    (ii) [Reserved]
    (3) For service information identified in this AD, contact your 
local Sikorsky Field Representative or Sikorsky's Service 
Engineering Group at Sikorsky Aircraft Corporation, 124 Quarry Road, 
Trumbull, CT 06611; telephone 1-800-Winged-S; email 
[email protected]. Operators may also log on to 
the Sikorsky 360 website at https://www.sikorsky360.com.
    (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.

    Issued on May 4, 2021.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-11081 Filed 5-26-21; 8:45 am]
BILLING CODE 4910-13-P