Special Conditions: Carson Helicopters Inc., Sikorsky Model S-61A, S-61L, and S-61N (Including Those Modified by Supplemental Type Certificate (STC) No. SH640NE) Helicopters; Overload Protection Device in a Hoist, 13705-13707 [2025-04567]

Download as PDF 13705 Proposed Rules Federal Register Vol. 90, No. 57 Wednesday, March 26, 2025 This section of the FEDERAL REGISTER contains notices to the public of the proposed issuance of rules and regulations. The purpose of these notices is to give interested persons an opportunity to participate in the rule making prior to the adoption of the final rules. DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 29 [Docket No. FAA–2024–2383; Notice No. 29– 24–02–SC] Special Conditions: Carson Helicopters Inc., Sikorsky Model S– 61A, S–61L, and S–61N (Including Those Modified by Supplemental Type Certificate (STC) No. SH640NE) Helicopters; Overload Protection Device in a Hoist Federal Aviation Administration (FAA), Department of Transportation. ACTION: Notice of proposed special conditions. AGENCY: This action proposes special conditions for a supplemental type certificate (STC) to install a helicopter hoist equipped with an overload protection device (OLPD) on Sikorsky Model S–61A, S–61L, and S–61N (including those modified by STC No. SH640NE, which shortens the S–61N by 50 inches) helicopters. These helicopters, as modified by Carson Helicopters, Inc. (Carson), will have a novel or unusual design feature when compared to the state of technology envisioned in the airworthiness standards for transport category rotorcraft. This design feature is an OLPD installed in the hoist. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature. These proposed special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards. DATES: Send comments on or before April 25, 2025. ADDRESSES: Send comments identified by Docket No. FAA–2024–2383 using any of the following methods: khammond on DSK9W7S144PROD with PROPOSALS SUMMARY: VerDate Sep<11>2014 16:00 Mar 25, 2025 Jkt 265001 Federal eRegulations Portal: Go to www.regulations.gov and follow the online instructions for sending your comments electronically. Mail: Send comments to Docket Operations, M–30, U.S. Department of Transportation (DOT), 1200 New Jersey Avenue SE, Room W12–140, West Building Ground Floor, Washington, DC 20590–0001. Hand Delivery or Courier: Take comments to Docket Operations in Room W12–140 of the West Building Ground Floor at 1200 New Jersey Avenue SE, Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. Fax: Fax comments to Docket Operations at 202–493–2251. Docket: Background documents or comments received may be read at www.regulations.gov at any time. Follow the online instructions for accessing the docket or go to Docket Operations in Room W12–140 of the West Building Ground Floor at 1200 New Jersey Avenue SE, Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. FOR FURTHER INFORMATION CONTACT: Scott Johnson, Mechanical Systems Section, AIR–623, Technical Policy Branch, Policy and Standards Division, Aircraft Certification Service, Federal Aviation Administration, telephone 202–267–4644; email Scott.R.Johnson@ faa.gov. SUPPLEMENTARY INFORMATION: Comments Invited The FAA invites interested people to take part in this rulemaking by sending written comments, data, or views. The most helpful comments reference a specific portion of the proposed special conditions, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date for comments and will consider comments filed late if it is possible to do so without incurring delay. The FAA may change these special conditions based on the comments received. Privacy Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in title 14, Code of Federal Regulations (14 CFR) PO 00000 Frm 00001 Fmt 4702 Sfmt 4702 11.35, the FAA will post all comments received without change to www.regulations.gov, including any personal information you provide. The FAA will also post a report summarizing each substantive verbal contact received about these special conditions. Confidential Business Information Confidential Business Information (CBI) is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to these special conditions contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to these special conditions, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as ‘‘PROPIN.’’ The FAA will treat such marked submissions as confidential under the FOIA, and the indicated comments will not be placed in the public docket of these proposed special conditions. Send submissions containing CBI to the individual listed in the contact section above. Comments the FAA receives, which are not specifically designated as CBI, will be placed in the public docket for these proposed special conditions. Background On September 21, 2021, Carson applied for an amendment to STC No. SR02507NY to add a hoist with an OLPD, to be installed on Sikorsky Model S–61A, S–61L, and S–61N (including those modified by STC No. SH640NE, which shortens the S–61N by 50 inches) helicopters. The S–61 helicopter is a twin-engine rotorcraft. The maximum takeoff weight is between 19,000 and 22,000 pounds, depending on configuration, and the helicopter has a maximum capacity of 39 passengers and a crew of 2. Type Certification Basis Under the provisions of § 21.101, Carson must show that the helicopters, for which they make application to modify by STC No. SR02507NY, as will be changed, continue to meet the applicable provisions of the regulations listed in each helicopter’s respective E:\FR\FM\26MRP1.SGM 26MRP1 13706 Federal Register / Vol. 90, No. 57 / Wednesday, March 26, 2025 / Proposed Rules type certificate or the applicable regulations in effect on the date of application for the change except for earlier amendments as agreed upon by the FAA. If the Administrator finds that the applicable airworthiness regulations (e.g., 14 CFR part 29) do not contain adequate or appropriate safety standards for the Sikorsky Model S–61A, S–61L, and S–61N (including those modified by STC No. SH640NE) helicopters because of a novel or unusual design feature, special conditions are prescribed under the provisions of § 21.16. Special conditions are initially applicable to the model for which they are issued. Should the applicant apply for a supplemental type certificate to modify any other model included on the same type certificate to incorporate the same novel or unusual design feature, these special conditions would also apply to the other model under § 21.101. In addition to the applicable airworthiness regulations and special conditions, the Sikorsky Model S–61A, S–61L, and S–61N (including those modified by STC No. SH640NE) helicopters must comply with the exhaust-emission requirements of part 34, and the noise-certification requirements of part 36. The FAA issues special conditions, as defined in § 11.19, in accordance with § 11.38, and they become part of the type certification basis under § 21.101. Novel or Unusual Design Feature The Sikorsky Model S–61A, S–61L, and S–61N (including those modified by STC No. SH640NE) helicopters will incorporate the following novel or unusual design feature: An OLPD installed in a hoist. khammond on DSK9W7S144PROD with PROPOSALS Discussion These special conditions are necessary because regulations concerning external load carriage requirements for part 29 rotorcraft do not address hoists that include an OLPD feature. In 1991 the FAA tasked the External Load Working Group (Working Group) of the Aviation Rulemaking Advisory Committee (ARAC) with investigating the need to complement the rotorcraft 14 CFR part 133 Class D external load carriage regulations (including transport of passengers external to the rotorcraft). Upon completion of their review, the Working Group issued a report 1 recommending updates to the external 1 External Load Working Group report https:// www.faa.gov/sites/faa.gov/files/advisory_ rulemaking_committees/RelwgT1-12041991.pdf. VerDate Sep<11>2014 16:00 Mar 25, 2025 Jkt 265001 load regulations in 14 CFR part 27 and part 29. Based on the Working Group’s report, the FAA recommended several changes to part 27 and part 29 to improve safety. On July 13, 1998, the FAA published a Notice of Proposed Rulemaking 2 (NPRM) (63 FR 37746). This NPRM proposed amendments to the airworthiness standards for rotorcraft load combination certification. The FAA issued the final rule based on this NPRM for part 27 at amendment 27–36 and part 29 at amendment 29–43; however, the revised parts 27 and 29 did not address OLPD features in hoist systems. As a result, the current §§ 27.865 and 29.865 do not address hoist systems with OLPD features. The hoist being installed by Carson includes an OLPD in its design. The OLPD reduces the likelihood of the loss of rotorcraft and crew due to an entanglement of the hoist cable. Upon activation, the OLPD affords the pilot time to respond and potentially jettison the load to save the aircraft and the crew onboard. Because the OLPD activation range is less than the limit static load factor for human external cargo published in §§ 27.865 and 29.865, it introduces a risk that the cable could completely unspool (i.e., loss of cargo), particularly if unspooling is not subsequently arrested once the load is reduced below the activation threshold. Despite this risk, the overall safety will be improved with the inclusion of this OLPD. Meeting the requirements of these proposed special conditions demonstrates that the OLPD in the hoist installed by Carson will activate to allow a slip and recapture in response to the load conditions outlined in these proposed special conditions. By ‘‘activation’’ the FAA means all states of its intended function, which consists of uncommanded cable payout (i.e., slippage) and the recapture of the load (i.e., arresting the slippage). The FAA intends the activation range to bound both payout and arrest. The FAA proposes that the activation range for these special conditions would be 2.2 to 3.2 times the rated load. The functionality and activation requirement comes from SAE AS6342, ‘‘Minimum Operational Performance Standard (MOPS) for Helicopter Hoist Systems,’’ December 2020, section 4.7 paragraph 2.3 The OLPD must slip and recapture load only within the activation range of 2 Docket No. 29277; Notice No. 98–6, ‘‘Rotorcraft Load Combination Safety Requirements.’’ 3 SAE AS6342 is available for purchase at https:// saemobilus.sae.org/standards/as6342-minimumoperational-performance-standard-mopshelicopter-hoist-systems. PO 00000 Frm 00002 Fmt 4702 Sfmt 4702 2.2 to 3.2 times the rated load. These special conditions do not change the structural limit load factors specified in §§ 27.865 and 29.865. These special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards. In addition to the activation range explained previously, the OLPD must be designed to continue working correctly or as expected in every way (i.e., function properly) when experiencing the maximum external limit load specified in §§ 27.865 and 29.865. Applicability As discussed above, these special conditions are applicable to the helicopter models listed on the AML of STC No. SR02507NY, which is available at DRS. Should Carson apply at a later date for a change to STC No. SR02507NY to include any new models on the AML to incorporate the same novel or unusual design feature, these special conditions would apply to that model as well. Conclusion This action only affects the application for an STC to approve installation of hoists that contain an OLPD listed on the AML of STC No. SR02507NY. It is not a rule of general applicability and affects only the applicant who applied to the FAA for approval of these features on the helicopter. List of Subjects in 14 CFR Part 29 Aircraft, Aviation safety, Reporting and recordkeeping requirements. Authority Citation The authority citation for these special conditions is as follows: Authority: 49 U.S.C. 106(f), 40113, 44701, 44702, and 44704. The Proposed Special Conditions Accordingly, the FAA proposes the following special conditions as part of the type certification basis for the Model S–61A, S–61L, and S–61N, and S–61N (including those modified by STC No. SH640NE) helicopters listed on the AML of STC No. SR02507NY, as modified by Carson. (a) The Overload Protection Device (OLPD) must: (1) Function properly for all loads up to and including the § 29.865(a) maximum external limit load. (2) Be designed to hold any load up to 2.2 times the rated load and shall activate between 2.2 times the rated load and 3.2 times the rated load. This E:\FR\FM\26MRP1.SGM 26MRP1 Federal Register / Vol. 90, No. 57 / Wednesday, March 26, 2025 / Proposed Rules activation range must take into account production and maintenance tolerances, variations due to the environment (e.g., temperature and humidity), and operations (e.g., length of cable paid out). The above requirements must be met over the entire activation range. (3) Protect the helicopter and cargo by incorporating design activation limits (i.e., defined set point(s)) which: (i) Prevent excess cable tension that might result in cable failure or loads on the helicopter that endanger the aircraft, (ii) Prevent uncommanded cable payout when experiencing cable loads below the activation range, (iii) Allow cable payout when experiencing loads above the activation range, and (iv) Arrest cable unspooling to prevent loss of cargo after an activation event. (b) The OLPD installation, maintenance, and inspection instructions must be made a part of the applicable section(s) of the Instructions for Continued Airworthiness (ICA). Issued in Kansas City, Missouri, on March 14, 2025. Patrick R. Mullen, Manager, Technical Policy Branch, Policy and Standards Division, Aircraft Certification Service. [FR Doc. 2025–04567 Filed 3–25–25; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2025–0475; Project Identifier MCAI–2024–00600–T] RIN 2120–AA64 Airworthiness Directives; Airbus SAS Airplanes Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: The FAA proposes to adopt a new airworthiness directive (AD) for all Airbus SAS Model A350–941 and –1041 airplanes. This proposed AD was prompted by a determination that the applicable aircraft flight manual (AFM) was providing an incorrect value for maximum cumulative taxi time in freezing fog conditions. This proposed AD would require revising the existing AFM to provide the flightcrew with normal procedures to follow under certain conditions, as specified in a European Union Aviation Safety Agency khammond on DSK9W7S144PROD with PROPOSALS SUMMARY: VerDate Sep<11>2014 16:00 Mar 25, 2025 Jkt 265001 (EASA) AD, which is proposed for incorporation by reference (IBR). The FAA is proposing this AD to address the unsafe condition on these products. DATES: The FAA must receive comments on this proposed AD by May 12, 2025. ADDRESSES: You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: • Federal eRulemaking Portal: Go to regulations.gov. Follow the instructions for submitting comments. • Fax: 202–493–2251. • Mail: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE, Washington, DC 20590. • Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA–2025–0475; 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 NPRM, the mandatory continuing airworthiness information (MCAI), any comments received, and other information. The street address for Docket Operations is listed above. Material Incorporated by Reference: • For EASA material identified in this proposed AD, contact EASA, KonradAdenauer-Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999 000; email ADs@easa.europa.eu; website easa.europa.eu. You may find this material on the EASA website at ad.easa.europa.eu. It is also available at regulations.gov under Docket No. FAA– 2025–0475. • You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206–231–3195. FOR FURTHER INFORMATION CONTACT: James Clary, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone: 817–222–5138; email: james.clary@faa.gov. SUPPLEMENTARY INFORMATION: Comments Invited The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the ADDRESSES section. Include ‘‘Docket No. FAA–2025–0475; Project Identifier MCAI–2024–00600–T’’ at the beginning of your comments. The most helpful comments reference a specific PO 00000 Frm 00003 Fmt 4702 Sfmt 4702 13707 portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this proposal because of those comments. Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM. Confidential Business Information CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as ‘‘PROPIN.’’ The FAA will treat such 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 James Clary, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone: 817–222–5138; email: james.clary@ 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 EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2024–0190, dated October 10, 2024; corrected October 11, 2024 (EASA AD 2024–0190) (also referred to as the MCAI), to correct an unsafe condition for all Airbus SAS Model A350–941, A350–1041, A380– 841, and A380–842 airplanes. The MCAI states the applicable AFM was providing an incorrect value for maximum cumulative taxi time in freezing fog conditions, which could lead to multiple engine surges in a critical flight phase and possibly result in loss of control of the airplane. The FAA is proposing this AD to address the unsafe condition on these products. E:\FR\FM\26MRP1.SGM 26MRP1

Agencies

[Federal Register Volume 90, Number 57 (Wednesday, March 26, 2025)]
[Proposed Rules]
[Pages 13705-13707]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-04567]


========================================================================
Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

========================================================================


Federal Register / Vol. 90, No. 57 / Wednesday, March 26, 2025 / 
Proposed Rules

[[Page 13705]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 29

[Docket No. FAA-2024-2383; Notice No. 29-24-02-SC]


Special Conditions: Carson Helicopters Inc., Sikorsky Model S-
61A, S-61L, and S-61N (Including Those Modified by Supplemental Type 
Certificate (STC) No. SH640NE) Helicopters; Overload Protection Device 
in a Hoist

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation.

ACTION: Notice of proposed special conditions.

-----------------------------------------------------------------------

SUMMARY: This action proposes special conditions for a supplemental 
type certificate (STC) to install a helicopter hoist equipped with an 
overload protection device (OLPD) on Sikorsky Model S-61A, S-61L, and 
S-61N (including those modified by STC No. SH640NE, which shortens the 
S-61N by 50 inches) helicopters. These helicopters, as modified by 
Carson Helicopters, Inc. (Carson), will have a novel or unusual design 
feature when compared to the state of technology envisioned in the 
airworthiness standards for transport category rotorcraft. This design 
feature is an OLPD installed in the hoist. The applicable airworthiness 
regulations do not contain adequate or appropriate safety standards for 
this design feature. These proposed special conditions contain the 
additional safety standards that the Administrator considers necessary 
to establish a level of safety equivalent to that established by the 
existing airworthiness standards.

DATES: Send comments on or before April 25, 2025.

ADDRESSES: Send comments identified by Docket No. FAA-2024-2383 using 
any of the following methods:
    Federal eRegulations Portal: Go to www.regulations.gov and follow 
the online instructions for sending your comments electronically.
    Mail: Send comments to Docket Operations, M-30, U.S. Department of 
Transportation (DOT), 1200 New Jersey Avenue SE, Room W12-140, West 
Building Ground Floor, Washington, DC 20590-0001.
    Hand Delivery or Courier: Take comments to Docket Operations in 
Room W12-140 of the West Building Ground Floor at 1200 New Jersey 
Avenue SE, Washington, DC, between 9 a.m. and 5 p.m., Monday through 
Friday, except Federal holidays.
    Fax: Fax comments to Docket Operations at 202-493-2251.
    Docket: Background documents or comments received may be read at 
www.regulations.gov at any time. Follow the online instructions for 
accessing the docket or go to Docket Operations in Room W12-140 of the 
West Building Ground Floor at 1200 New Jersey Avenue SE, Washington, 
DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays.

FOR FURTHER INFORMATION CONTACT: Scott Johnson, Mechanical Systems 
Section, AIR-623, Technical Policy Branch, Policy and Standards 
Division, Aircraft Certification Service, Federal Aviation 
Administration, telephone 202-267-4644; email [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites interested people to take part in this rulemaking 
by sending written comments, data, or views. The most helpful comments 
reference a specific portion of the proposed special conditions, 
explain the reason for any recommended change, and include supporting 
data.
    The FAA will consider all comments received by the closing date for 
comments and will consider comments filed late if it is possible to do 
so without incurring delay. The FAA may change these special conditions 
based on the comments received.

Privacy

    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in title 
14, Code of Federal Regulations (14 CFR) 11.35, the FAA will post all 
comments received without change to www.regulations.gov, including any 
personal information you provide. The FAA will also post a report 
summarizing each substantive verbal contact received about these 
special conditions.

Confidential Business Information

    Confidential Business Information (CBI) is commercial or financial 
information that is both customarily and actually treated as private by 
its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), 
CBI is exempt from public disclosure. If your comments responsive to 
these special conditions contain commercial or financial information 
that is customarily treated as private, that you actually treat as 
private, and that is relevant or responsive to these special 
conditions, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and the indicated comments will not be 
placed in the public docket of these proposed special conditions. Send 
submissions containing CBI to the individual listed in the contact 
section above. Comments the FAA receives, which are not specifically 
designated as CBI, will be placed in the public docket for these 
proposed special conditions.

Background

    On September 21, 2021, Carson applied for an amendment to STC No. 
SR02507NY to add a hoist with an OLPD, to be installed on Sikorsky 
Model S-61A, S-61L, and S-61N (including those modified by STC No. 
SH640NE, which shortens the S-61N by 50 inches) helicopters. The S-61 
helicopter is a twin-engine rotorcraft. The maximum takeoff weight is 
between 19,000 and 22,000 pounds, depending on configuration, and the 
helicopter has a maximum capacity of 39 passengers and a crew of 2.

Type Certification Basis

    Under the provisions of Sec.  21.101, Carson must show that the 
helicopters, for which they make application to modify by STC No. 
SR02507NY, as will be changed, continue to meet the applicable 
provisions of the regulations listed in each helicopter's respective

[[Page 13706]]

type certificate or the applicable regulations in effect on the date of 
application for the change except for earlier amendments as agreed upon 
by the FAA.
    If the Administrator finds that the applicable airworthiness 
regulations (e.g., 14 CFR part 29) do not contain adequate or 
appropriate safety standards for the Sikorsky Model S-61A, S-61L, and 
S-61N (including those modified by STC No. SH640NE) helicopters because 
of a novel or unusual design feature, special conditions are prescribed 
under the provisions of Sec.  21.16.
    Special conditions are initially applicable to the model for which 
they are issued. Should the applicant apply for a supplemental type 
certificate to modify any other model included on the same type 
certificate to incorporate the same novel or unusual design feature, 
these special conditions would also apply to the other model under 
Sec.  21.101.
    In addition to the applicable airworthiness regulations and special 
conditions, the Sikorsky Model S-61A, S-61L, and S-61N (including those 
modified by STC No. SH640NE) helicopters must comply with the exhaust-
emission requirements of part 34, and the noise-certification 
requirements of part 36.
    The FAA issues special conditions, as defined in Sec.  11.19, in 
accordance with Sec.  11.38, and they become part of the type 
certification basis under Sec.  21.101.

Novel or Unusual Design Feature

    The Sikorsky Model S-61A, S-61L, and S-61N (including those 
modified by STC No. SH640NE) helicopters will incorporate the following 
novel or unusual design feature:
    An OLPD installed in a hoist.

Discussion

    These special conditions are necessary because regulations 
concerning external load carriage requirements for part 29 rotorcraft 
do not address hoists that include an OLPD feature.
    In 1991 the FAA tasked the External Load Working Group (Working 
Group) of the Aviation Rulemaking Advisory Committee (ARAC) with 
investigating the need to complement the rotorcraft 14 CFR part 133 
Class D external load carriage regulations (including transport of 
passengers external to the rotorcraft). Upon completion of their 
review, the Working Group issued a report \1\ recommending updates to 
the external load regulations in 14 CFR part 27 and part 29.
---------------------------------------------------------------------------

    \1\ External Load Working Group report https://www.faa.gov/sites/faa.gov/files/advisory_rulemaking_committees/RelwgT1-12041991.pdf.
---------------------------------------------------------------------------

    Based on the Working Group's report, the FAA recommended several 
changes to part 27 and part 29 to improve safety. On July 13, 1998, the 
FAA published a Notice of Proposed Rulemaking \2\ (NPRM) (63 FR 37746). 
This NPRM proposed amendments to the airworthiness standards for 
rotorcraft load combination certification. The FAA issued the final 
rule based on this NPRM for part 27 at amendment 27-36 and part 29 at 
amendment 29-43; however, the revised parts 27 and 29 did not address 
OLPD features in hoist systems. As a result, the current Sec. Sec.  
27.865 and 29.865 do not address hoist systems with OLPD features.
---------------------------------------------------------------------------

    \2\ Docket No. 29277; Notice No. 98-6, ``Rotorcraft Load 
Combination Safety Requirements.''
---------------------------------------------------------------------------

    The hoist being installed by Carson includes an OLPD in its design. 
The OLPD reduces the likelihood of the loss of rotorcraft and crew due 
to an entanglement of the hoist cable. Upon activation, the OLPD 
affords the pilot time to respond and potentially jettison the load to 
save the aircraft and the crew onboard.
    Because the OLPD activation range is less than the limit static 
load factor for human external cargo published in Sec. Sec.  27.865 and 
29.865, it introduces a risk that the cable could completely unspool 
(i.e., loss of cargo), particularly if unspooling is not subsequently 
arrested once the load is reduced below the activation threshold. 
Despite this risk, the overall safety will be improved with the 
inclusion of this OLPD. Meeting the requirements of these proposed 
special conditions demonstrates that the OLPD in the hoist installed by 
Carson will activate to allow a slip and recapture in response to the 
load conditions outlined in these proposed special conditions. By 
``activation'' the FAA means all states of its intended function, which 
consists of uncommanded cable payout (i.e., slippage) and the recapture 
of the load (i.e., arresting the slippage). The FAA intends the 
activation range to bound both payout and arrest. The FAA proposes that 
the activation range for these special conditions would be 2.2 to 3.2 
times the rated load. The functionality and activation requirement 
comes from SAE AS6342, ``Minimum Operational Performance Standard 
(MOPS) for Helicopter Hoist Systems,'' December 2020, section 4.7 
paragraph 2.\3\ The OLPD must slip and recapture load only within the 
activation range of 2.2 to 3.2 times the rated load. These special 
conditions do not change the structural limit load factors specified in 
Sec. Sec.  27.865 and 29.865. These special conditions contain the 
additional safety standards that the Administrator considers necessary 
to establish a level of safety equivalent to that established by the 
existing airworthiness standards.
---------------------------------------------------------------------------

    \3\ SAE AS6342 is available for purchase at https://saemobilus.sae.org/standards/as6342-minimum-operational-performance-standard-mops-helicopter-hoist-systems.
---------------------------------------------------------------------------

    In addition to the activation range explained previously, the OLPD 
must be designed to continue working correctly or as expected in every 
way (i.e., function properly) when experiencing the maximum external 
limit load specified in Sec. Sec.  27.865 and 29.865.

Applicability

    As discussed above, these special conditions are applicable to the 
helicopter models listed on the AML of STC No. SR02507NY, which is 
available at DRS. Should Carson apply at a later date for a change to 
STC No. SR02507NY to include any new models on the AML to incorporate 
the same novel or unusual design feature, these special conditions 
would apply to that model as well.

Conclusion

    This action only affects the application for an STC to approve 
installation of hoists that contain an OLPD listed on the AML of STC 
No. SR02507NY. It is not a rule of general applicability and affects 
only the applicant who applied to the FAA for approval of these 
features on the helicopter.

List of Subjects in 14 CFR Part 29

    Aircraft, Aviation safety, Reporting and recordkeeping 
requirements.

Authority Citation

    The authority citation for these special conditions is as follows:

    Authority: 49 U.S.C. 106(f), 40113, 44701, 44702, and 44704.

The Proposed Special Conditions

    Accordingly, the FAA proposes the following special conditions as 
part of the type certification basis for the Model S-61A, S-61L, and S-
61N, and S-61N (including those modified by STC No. SH640NE) 
helicopters listed on the AML of STC No. SR02507NY, as modified by 
Carson.
    (a) The Overload Protection Device (OLPD) must:
    (1) Function properly for all loads up to and including the Sec.  
29.865(a) maximum external limit load.
    (2) Be designed to hold any load up to 2.2 times the rated load and 
shall activate between 2.2 times the rated load and 3.2 times the rated 
load. This

[[Page 13707]]

activation range must take into account production and maintenance 
tolerances, variations due to the environment (e.g., temperature and 
humidity), and operations (e.g., length of cable paid out). The above 
requirements must be met over the entire activation range.
    (3) Protect the helicopter and cargo by incorporating design 
activation limits (i.e., defined set point(s)) which:
    (i) Prevent excess cable tension that might result in cable failure 
or loads on the helicopter that endanger the aircraft,
    (ii) Prevent uncommanded cable payout when experiencing cable loads 
below the activation range,
    (iii) Allow cable payout when experiencing loads above the 
activation range, and
    (iv) Arrest cable unspooling to prevent loss of cargo after an 
activation event.
    (b) The OLPD installation, maintenance, and inspection instructions 
must be made a part of the applicable section(s) of the Instructions 
for Continued Airworthiness (ICA).

    Issued in Kansas City, Missouri, on March 14, 2025.
Patrick R. Mullen,
Manager, Technical Policy Branch, Policy and Standards Division, 
Aircraft Certification Service.
[FR Doc. 2025-04567 Filed 3-25-25; 8:45 am]
BILLING CODE 4910-13-P
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