Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters, 12550-12552 [2021-03950]

Download as PDF 12550 Proposed Rules Federal Register Vol. 86, No. 41 Thursday, March 4, 2021 [Docket No. FAA–2021–0106; Project Identifier AD–2020–00708–R] Service Engineering Group at Sikorsky Aircraft Corporation, Mailstop K100, 124 Quarry Road, Trumbull, CT 06611; telephone 1–800–946–4337 (1–800– Winged–S); email wcs_cust_service_ eng.gr-sik@lmco.com. 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. RIN 2120–AA64 Examining the AD Docket 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 39 Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: The FAA proposes to adopt a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S–92A helicopters. This proposed AD was prompted by an incident of a side facing utility seat detaching from wall attachment points. This proposed AD would require modifying certain side facing utility seats and observer seats. This proposed AD would also prohibit installing those seats unless the modification has been accomplished. 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 April 19, 2021. 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 https://www.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. For service information identified in this NPRM, contact your local Sikorsky Field Representative or Sikorsky’s jbell on DSKJLSW7X2PROD with PROPOSALS SUMMARY: VerDate Sep<11>2014 18:38 Mar 03, 2021 Jkt 253001 You may examine the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA–2021–0106; 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, any comments received, and other information. The street address for Docket Operations is listed above. FOR FURTHER INFORMATION CONTACT: Dorie Resnik, Aerospace Engineer, Aviation Safety Section, Boston ACO Branch, FAA, 1200 District Ave., Burlington, MA 01803; phone: (781) 238–7693; email: dorie.resnik@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 ADDRESSES. Include ‘‘Docket No. FAA–2021–0106; Project Identifier AD– 2020–00708–R’’ at the beginning of your comments. The most helpful comments reference a specific 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 https:// www.regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM. PO 00000 Frm 00001 Fmt 4702 Sfmt 4702 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 Dorie Resnik, Aerospace Engineer, Aviation Safety Section, Boston ACO Branch, FAA, 1200 District Ave., Burlington, MA 01803; phone: (781) 238–7693; email: dorie.resnik@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 The FAA proposes to adopt a new AD for Sikorsky Model S–92A helicopters with certain Martin-Baker side facing utility seats and observer seats installed. This proposed AD was prompted by an incident of a side facing utility seat detaching from wall attachment points during dynamic testing. The root cause has been identified as a change in the finishing process of the main back tube. Due to design similarity, certain observer seats are also subject to this unsafe condition. Accordingly, this proposed AD would require replacing the main back tube assembly in affected side facing utility seats and observer seats. This proposed AD would also prohibit installing those seats unless the main back tube assembly has been replaced. This condition, if not addressed, could result in increased surface friction in the direction of the seat attenuation, failure of proper utility seat attenuation during a crash event, excessive lumbar loads in an observer seat during a crash event, and subsequent excessive or fatal occupant injury. E:\FR\FM\04MRP1.SGM 04MRP1 Federal Register / Vol. 86, No. 41 / Thursday, March 4, 2021 / Proposed Rules FAA’s Determination The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design. Related Service Information Under 1 CFR Part 51 The FAA reviewed Martin-Baker Special Information Leaflet (SIL) No. 831, dated July 10, 2019 (SIL 831), for side facing utility seat supplier part number (P/N) MBCS12410AA001, and Martin-Baker SIL No. 833, dated July 11, 2019 (SIL 833), for observer seat supplier P/N MBCS12200 and MBCS7301–2. This service information specifies procedures for disassembling the seat, inspecting components, replacing the main back tube assembly (tube assembly, back main), and reassembling, testing, and marking the seat. SIL 831 and SIL 833 are attached to Sikorsky S–92A Helicopter Alert Service Bulletin 92–25–026, dated March 5, 2020 (ASB 92–25–026). The FAA also reviewed ASB 92–25– 026, which specifies procedures for preparing the helicopter for replacing the main back tube assembly by following SIL 831 or SIL 833, as applicable to your seat. This service information specifies removing existing placards, complying with the applicable SIL, reinstalling the removed placards, inspecting for foreign object debris (FOD), and cleaning. 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 ADDRESSES. jbell on DSKJLSW7X2PROD with PROPOSALS Proposed AD Requirements in This NPRM This proposed AD would require, within 125 hours time-in-service (TIS) or six months after the effective date of this AD, whichever occurs first, removing certain placards, accomplishing the actions specified in SIL 831 or SIL 833 already described, and reinstalling the previously removed placards. Differences Between This Proposed AD and the Service Information ASB 92–25–026 specifies a compliance time of no later than March 5, 2021; where this proposed AD specifies a compliance time of within 125 hours TIS or six months after the effective date of this AD, whichever occurs first. ASB 92–25–026 specifies inspecting for FOD and cleaning; whereas this proposed AD does not. SIL 831 and SIL 833 specify destroying and disposing removed main back tube VerDate Sep<11>2014 18:38 Mar 03, 2021 Jkt 253001 assemblies and discarding removed split pins and tie down straps; whereas this proposed AD would require removing those parts from service instead. The service information specifies recording compliance; whereas this proposed AD does not. Costs of Compliance The FAA estimates that this AD, if adopted as proposed, would affect 9 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 proposed AD. Replacing a main back tube assembly would take about 2 work-hours and parts would cost about $11,217, for an estimated cost of about $11,387 per seat. Each helicopter could have up to 19 affected seats, which would take up to 38 work-hours and parts would cost up to about $213,123, for an estimated cost of up to about $216,353 per helicopter and $1,947,177 for the U.S. fleet. The FAA has included all known costs in its cost estimate. According to the manufacturer, however, some of the costs of this proposed AD may be covered under warranty, thereby reducing the cost impact on affected operators. 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 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 PO 00000 Frm 00002 Fmt 4702 Sfmt 4702 12551 responsibilities among the various levels of government. For the reasons discussed above, I certify this proposed regulation: (1) Is not a ‘‘significant regulatory action’’ under Executive Order 12866, (2) Would not affect intrastate aviation in Alaska, and (3) Would 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 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. § 39.13 [Amended] 2. The FAA amends § 39.13 by adding the following new airworthiness directive: ■ Sikorsky Aircraft Corporation: Docket No. FAA–2021–0106; Project Identifier AD– 2020–00708–R. (a) Comments Due Date The FAA must receive comments on this airworthiness directive (AD) by April 19, 2021. (b) Affected ADs None. (c) Applicability This AD applies to Sikorsky Aircraft Corporation Model S–92A helicopters, certificated in any category, with the following installed: (1) A Martin-Baker side facing utility seat supplier part number (P/N) MBCS12410AA001 with a serial number (S/N) identified in Table 2 of Martin-Baker Special Information Leaflet (SIL) No. 831, dated July 10, 2019 (SIL 831), that is not marked with ‘‘SIL831 incorporated;’’ or (2) A Martin-Baker observer seat supplier P/N MBCS12200 or MBCS7301–2 with an S/N identified in Table 2 of Martin-Baker SIL No. 833, dated July 11, 2019 (SIL 833), that is not marked with ‘‘SIL833 incorporated.’’ Note 1 to paragraph (c): SIL 831 and SIL 833 are attached to Sikorsky S–92A Helicopter Alert Service Bulletin 92–25–026, dated March 5, 2020 (ASB 92–25–026). Note 2 to paragraph (c): Section 3., the Accomplishment Instructions, Tables 1 and 2 of ASB 92–25–026, specify cross references E:\FR\FM\04MRP1.SGM 04MRP1 12552 Federal Register / Vol. 86, No. 41 / Thursday, March 4, 2021 / Proposed Rules of Martin-Baker supplier P/Ns with Sikorsky P/Ns and kit P/Ns. of the local flight standards district office/ certificate holding district office. Note 3 to paragraph (c): The marking ‘‘SIL831 incorporated’’ or ‘‘SIL833 incorporated,’’ as applicable, could be located adjacent to identification labels on the underside of the sitting platform assembly P/N MBCS4111. (i) Related Information (1) For more information about this AD, contact Dorie Resnik, Aerospace Engineer, Aviation Safety Section, Boston ACO Branch, FAA, 1200 District Ave., Burlington, MA 01803; phone: (781) 238–7693; email: dorie.resnik@faa.gov. (2) For service information identified in this AD, contact your local Sikorsky Field Representative or Sikorsky’s Service Engineering Group at Sikorsky Aircraft Corporation, Mailstop K100, 124 Quarry Road, Trumbull, CT 06611; telephone 1–800– 946–4337 (1–800–Winged–S); email wcs_ cust_service_eng.gr-sik@lmco.com. Operators may also log on to the Sikorsky 360 website at https://www.sikorsky360.com. You may view this 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. (d) Subject Joint Aircraft System Component (JASC) Code: 2500, Cabin Equipment/Furnishings; and 2520, Passenger Compartment Equipment. (e) Unsafe Condition This AD was prompted by an incident of a side facing utility seat detaching from wall attachment points during dynamic testing. The FAA is issuing this AD to detect and address a main back tube, a component of the main back tube assembly, which does not meet design requirements. The unsafe condition, if not addressed, could result in increased surface friction in the direction of the seat attenuation, failure of proper utility seat attenuation during a crash event, excessive lumbar loads in an observer seat during a crash event, and subsequent excessive or fatal occupant injury. (f) Compliance Comply with this AD within the compliance times specified, unless already done. jbell on DSKJLSW7X2PROD with PROPOSALS (g) Required Actions (1) Within 125 hours time-in-service or six months after the effective date of this AD, whichever occurs first, replace each main back tube assembly by following Section 3., Accomplishment Instructions, paragraphs C. through E., of ASB 92–25–026; except where the service information referenced in ASB 92–25–026 specifies destroying and disposing of parts or discarding parts, this AD requires removing those parts from service instead. Note 4 to paragraph (g)(1): SIL 831 and SIL 833, referred to in ASB 92–25–026, refer to main back tube assembly as tube assembly, back main. (2) As of the effective date of this AD, do not install a Martin-Baker side facing utility seat identified in paragraph (c)(1) of this AD or a Martin-Baker observer seat identified in paragraph (c)(2) of this AD unless the actions in paragraph (g)(1) have been accomplished. (h) Alternative Methods of Compliance (AMOCs) (1) The Manager, Boston ACO 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 certification office, send it to the attention of the person identified in paragraph (i)(1) of this AD. (2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager VerDate Sep<11>2014 18:38 Mar 03, 2021 Jkt 253001 Issued on February 19, 2021. Lance T. Gant, Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2021–03950 Filed 3–3–21; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 73 [Docket No. FAA–2020–1053; Airspace Docket No. 20–ANM–32] RIN 2120–AA66 Proposed Amendment of Restricted Area R–7001C and Establishment of Restricted Areas R–7001D, R–7002A, R–7002B, and R–7002C; Guernsey, WY Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: This action proposes to amend restricted area R–7001C and establish three restricted areas, R– 7001D, R–7002A, R–7002B, and R– 7002C at Guernsey, WY. The Wyoming Army National Guard (WYARNG) requested the establishment of the new restricted areas to support its air-toground firing from helicopters and longer range artillery training. This additional airspace allows for the segregation of hazardous activities from non-participating air traffic. The FAA is also proposing to amend R–7001C to correct an inadvertent error to ensure proper vertical separation. DATES: Comments must be received on or before April 19, 2021. SUMMARY: PO 00000 Frm 00003 Fmt 4702 Sfmt 4702 Send comments on this proposal to the U.S. Department of Transportation, Docket Operations, 1200 New Jersey Avenue SE, West Building Ground Floor, Room W12–140, Washington, DC 20590–0001; telephone: 1 (800) 647–5527, or (202) 366–9826. You must identify FAA Docket Number FAA–2020–0153; Airspace Docket No. 20–ANM–32 at the beginning of your comments. You may also submit comments through the internet at https://www.regulations.gov. FOR FURTHER INFORMATION CONTACT: Christopher McMullin, Rules and Regulations Group, Office of Policy, Federal Aviation Administration, 800 Independence Avenue SW, Washington, DC 20591; telephone: (202) 267–8783. SUPPLEMENTARY INFORMATION: ADDRESSES: Authority for This Rulemaking The FAA’s authority to issue rules regarding aviation safety is found in Title 49 of the United States Code (U.S.C.). 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. This rulemaking is promulgated under the authority described in Subtitle VII, Part A, Subpart I, Section 40103. Under that section, the FAA is charged with prescribing regulations to assign the use of the airspace necessary to ensure the safety of aircraft and the efficient use of airspace. This regulation is within the scope of that authority as it would amend and establish restricted area airspace at Guernsey, WY, to contain activities deemed hazardous to nonparticipating aircraft. Comments Invited Interested parties are invited to participate in this proposed rulemaking by submitting such written data, views, or arguments as they may desire. Comments that provide the factual basis supporting the views and suggestions presented are particularly helpful in developing reasoned regulatory decisions on the proposal. Comments are specifically invited on the overall regulatory, aeronautical, economic, environmental, and energy-related aspects of the proposal. Communications should identify both docket numbers (FAA Docket Number FAA–2020–0153; Airspace Docket No. 20–ANM–32) and be submitted in triplicate to the Docket Management Facility (see ADDRESSES section for address and phone number). You may also submit comments through the internet at https://www.regulations.gov. Commenters wishing the FAA to acknowledge receipt of their comments E:\FR\FM\04MRP1.SGM 04MRP1

Agencies

[Federal Register Volume 86, Number 41 (Thursday, March 4, 2021)]
[Proposed Rules]
[Pages 12550-12552]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-03950]


========================================================================
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. 86, No. 41 / Thursday, March 4, 2021 / 
Proposed Rules

[[Page 12550]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0106; Project Identifier AD-2020-00708-R]
RIN 2120-AA64


Airworthiness Directives; Sikorsky Aircraft Corporation 
Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. 
This proposed AD was prompted by an incident of a side facing utility 
seat detaching from wall attachment points. This proposed AD would 
require modifying certain side facing utility seats and observer seats. 
This proposed AD would also prohibit installing those seats unless the 
modification has been accomplished. 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 April 19, 
2021.

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 https://www.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.
    For service information identified in this NPRM, contact your local 
Sikorsky Field Representative or Sikorsky's Service Engineering Group 
at Sikorsky Aircraft Corporation, Mailstop K100, 124 Quarry Road, 
Trumbull, CT 06611; telephone 1-800-946-4337 (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.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0106; 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, any comments 
received, and other information. The street address for Docket 
Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Dorie Resnik, Aerospace Engineer, 
Aviation Safety Section, Boston ACO Branch, FAA, 1200 District Ave., 
Burlington, MA 01803; phone: (781) 238-7693; email: 
[email protected].

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 ADDRESSES. Include ``Docket No. FAA-2021-0106; Project Identifier 
AD-2020-00708-R'' at the beginning of your comments. The most helpful 
comments reference a specific 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 
https://www.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 Dorie 
Resnik, Aerospace Engineer, Aviation Safety Section, Boston ACO Branch, 
FAA, 1200 District Ave., Burlington, MA 01803; phone: (781) 238-7693; 
email: [email protected]. Any commentary that the FAA receives which 
is not specifically designated as CBI will be placed in the public 
docket for this rulemaking.

Background

    The FAA proposes to adopt a new AD for Sikorsky Model S-92A 
helicopters with certain Martin-Baker side facing utility seats and 
observer seats installed. This proposed AD was prompted by an incident 
of a side facing utility seat detaching from wall attachment points 
during dynamic testing. The root cause has been identified as a change 
in the finishing process of the main back tube. Due to design 
similarity, certain observer seats are also subject to this unsafe 
condition.
    Accordingly, this proposed AD would require replacing the main back 
tube assembly in affected side facing utility seats and observer seats. 
This proposed AD would also prohibit installing those seats unless the 
main back tube assembly has been replaced. This condition, if not 
addressed, could result in increased surface friction in the direction 
of the seat attenuation, failure of proper utility seat attenuation 
during a crash event, excessive lumbar loads in an observer seat during 
a crash event, and subsequent excessive or fatal occupant injury.

[[Page 12551]]

FAA's Determination

    The FAA is issuing this NPRM after determining that the unsafe 
condition described previously is likely to exist or develop on other 
products of the same type design.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Martin-Baker Special Information Leaflet (SIL) No. 
831, dated July 10, 2019 (SIL 831), for side facing utility seat 
supplier part number (P/N) MBCS12410AA001, and Martin-Baker SIL No. 
833, dated July 11, 2019 (SIL 833), for observer seat supplier P/N 
MBCS12200 and MBCS7301-2. This service information specifies procedures 
for disassembling the seat, inspecting components, replacing the main 
back tube assembly (tube assembly, back main), and reassembling, 
testing, and marking the seat. SIL 831 and SIL 833 are attached to 
Sikorsky S-92A Helicopter Alert Service Bulletin 92-25-026, dated March 
5, 2020 (ASB 92-25-026).
    The FAA also reviewed ASB 92-25-026, which specifies procedures for 
preparing the helicopter for replacing the main back tube assembly by 
following SIL 831 or SIL 833, as applicable to your seat. This service 
information specifies removing existing placards, complying with the 
applicable SIL, reinstalling the removed placards, inspecting for 
foreign object debris (FOD), and cleaning.
    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 ADDRESSES.

Proposed AD Requirements in This NPRM

    This proposed AD would require, within 125 hours time-in-service 
(TIS) or six months after the effective date of this AD, whichever 
occurs first, removing certain placards, accomplishing the actions 
specified in SIL 831 or SIL 833 already described, and reinstalling the 
previously removed placards.

Differences Between This Proposed AD and the Service Information

    ASB 92-25-026 specifies a compliance time of no later than March 5, 
2021; where this proposed AD specifies a compliance time of within 125 
hours TIS or six months after the effective date of this AD, whichever 
occurs first. ASB 92-25-026 specifies inspecting for FOD and cleaning; 
whereas this proposed AD does not. SIL 831 and SIL 833 specify 
destroying and disposing removed main back tube assemblies and 
discarding removed split pins and tie down straps; whereas this 
proposed AD would require removing those parts from service instead. 
The service information specifies recording compliance; whereas this 
proposed AD does not.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 9 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 proposed AD.
    Replacing a main back tube assembly would take about 2 work-hours 
and parts would cost about $11,217, for an estimated cost of about 
$11,387 per seat. Each helicopter could have up to 19 affected seats, 
which would take up to 38 work-hours and parts would cost up to about 
$213,123, for an estimated cost of up to about $216,353 per helicopter 
and $1,947,177 for the U.S. fleet.
    The FAA has included all known costs in its cost estimate. 
According to the manufacturer, however, some of the costs of this 
proposed AD may be covered under warranty, thereby reducing the cost 
impact on affected operators.

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

    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 above, I certify this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Would not affect intrastate aviation in Alaska, and
    (3) Would 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 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

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:

Sikorsky Aircraft Corporation: Docket No. FAA-2021-0106; Project 
Identifier AD-2020-00708-R.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by April 19, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Sikorsky Aircraft Corporation Model S-92A 
helicopters, certificated in any category, with the following 
installed:
    (1) A Martin-Baker side facing utility seat supplier part number 
(P/N) MBCS12410AA001 with a serial number (S/N) identified in Table 
2 of Martin-Baker Special Information Leaflet (SIL) No. 831, dated 
July 10, 2019 (SIL 831), that is not marked with ``SIL831 
incorporated;'' or
    (2) A Martin-Baker observer seat supplier P/N MBCS12200 or 
MBCS7301-2 with an S/N identified in Table 2 of Martin-Baker SIL No. 
833, dated July 11, 2019 (SIL 833), that is not marked with ``SIL833 
incorporated.''

    Note 1 to paragraph (c): SIL 831 and SIL 833 are attached to 
Sikorsky S-92A Helicopter Alert Service Bulletin 92-25-026, dated 
March 5, 2020 (ASB 92-25-026).


    Note 2 to paragraph (c): Section 3., the Accomplishment 
Instructions, Tables 1 and 2 of ASB 92-25-026, specify cross 
references

[[Page 12552]]

of Martin-Baker supplier P/Ns with Sikorsky P/Ns and kit P/Ns.


    Note 3 to paragraph (c): The marking ``SIL831 incorporated'' or 
``SIL833 incorporated,'' as applicable, could be located adjacent to 
identification labels on the underside of the sitting platform 
assembly P/N MBCS4111.

(d) Subject

    Joint Aircraft System Component (JASC) Code: 2500, Cabin 
Equipment/Furnishings; and 2520, Passenger Compartment Equipment.

(e) Unsafe Condition

    This AD was prompted by an incident of a side facing utility 
seat detaching from wall attachment points during dynamic testing. 
The FAA is issuing this AD to detect and address a main back tube, a 
component of the main back tube assembly, which does not meet design 
requirements. The unsafe condition, if not addressed, could result 
in increased surface friction in the direction of the seat 
attenuation, failure of proper utility seat attenuation during a 
crash event, excessive lumbar loads in an observer seat during a 
crash event, and subsequent excessive or fatal occupant injury.

(f) Compliance

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

(g) Required Actions

    (1) Within 125 hours time-in-service or six months after the 
effective date of this AD, whichever occurs first, replace each main 
back tube assembly by following Section 3., Accomplishment 
Instructions, paragraphs C. through E., of ASB 92-25-026; except 
where the service information referenced in ASB 92-25-026 specifies 
destroying and disposing of parts or discarding parts, this AD 
requires removing those parts from service instead.

    Note 4 to paragraph (g)(1): SIL 831 and SIL 833, referred to in 
ASB 92-25-026, refer to main back tube assembly as tube assembly, 
back main.

    (2) As of the effective date of this AD, do not install a 
Martin-Baker side facing utility seat identified in paragraph (c)(1) 
of this AD or a Martin-Baker observer seat identified in paragraph 
(c)(2) of this AD unless the actions in paragraph (g)(1) have been 
accomplished.

(h) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Boston ACO 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 certification office, send it to the attention of the 
person identified in paragraph (i)(1) of this AD.
    (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.

(i) Related Information

    (1) For more information about this AD, contact Dorie Resnik, 
Aerospace Engineer, Aviation Safety Section, Boston ACO Branch, FAA, 
1200 District Ave., Burlington, MA 01803; phone: (781) 238-7693; 
email: [email protected].
    (2) For service information identified in this AD, contact your 
local Sikorsky Field Representative or Sikorsky's Service 
Engineering Group at Sikorsky Aircraft Corporation, Mailstop K100, 
124 Quarry Road, Trumbull, CT 06611; telephone 1-800-946-4337 (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 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.

    Issued on February 19, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-03950 Filed 3-3-21; 8:45 am]
BILLING CODE 4910-13-P