Document ID: FAA-2016-8501-0004
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Sikorsky Aircraft Corporation Helicopters
Posted Date: 2018-12-26T05:00Z

[Federal Register Volume 83, Number 246 (Wednesday, December 26, 2018)]
[Proposed Rules]
[Pages 66167-66172]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-27713]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-8501; Product Identifier 2014-SW-042-AD]
RIN 2120-AA64

Airworthiness Directives; Sikorsky Aircraft Corporation 
Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (SNPRM); reopening 
of comment period.

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SUMMARY: We are revising an earlier proposal for Sikorsky Aircraft 
Corporation (Sikorsky) Model S-92A helicopters. This action revises the 
notice of proposed rulemaking (NPRM) by increasing the estimated costs 
of compliance and removing the daily inspection requirements. We are 
proposing this airworthiness directive (AD) to address the unsafe 
condition on these products. Since these actions would impose an 
additional economic burden over that proposed in the NPRM, we are 
reopening the comment period to allow the public the chance to comment 
on this change.

DATES: The comment period for the NPRM published in the Federal 
Register on July 15, 2016 (81 FR 46002), is reopened.
    We must receive comments on this SNPRM by February 11, 2019.

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 http://www.regulations.gov. Follow the instructions for submitting comments.

[[Page 66168]]

     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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this SNPRM, contact Sikorsky 
Aircraft Corporation, Customer Service Engineering, 124 Quarry Road, 
Trumbull, CT 06611; telephone 1-800-Winged-S or 203-416-4299; email: 
wcs_cust_service_eng.gr-sik@lmco.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.

Examining the AD Docket

    You may examine the AD docket on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2016-
8501; 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 SNPRM, the regulatory evaluation, any comments received, and other 
information. The street address for Docket Operations (phone: 800-647-
5527) is in the ADDRESSES section. Comments will be available in the AD 
docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Kristopher Greer, Aviation Safety 
Engineer, Boston ACO Branch, Compliance and Airworthiness Division, 
1200 District Avenue, Burlington, Massachusetts 01803; telephone (781) 
238-7799; email Kristopher.Greer@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite 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-2016-8501; 
Product Identifier 2014-SW-042-AD'' at the beginning of your comments. 
We specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of this SNPRM. We will consider all 
comments received by the closing date and may amend this SNPRM because 
of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this SNPRM.

Discussion

    We issued an NPRM to amend 14 CFR part 39 by adding an AD that 
would apply to Sikorsky Model S-92A helicopters with certain part-
numbered frame assemblies installed. The NPRM published in the Federal 
Register on July 15, 2016 (81 FR 46002). The NPRM was prompted by 
fatigue analysis indicating the possible development of stress 
concentrations at the steel doublers on the main transmission airframe 
support structure top deck, as well as the discovery of a helicopter 
with a crack in the STA 362 frame and skin. The NPRM proposed to 
require inspecting the main transmission forward and aft frame 
assemblies and adjacent skins for a crack and loose fasteners and 
replacing or repairing any cracked part or loose fastener. The NPRM 
also proposed to require establishing life limits for certain frame 
assemblies. The proposed requirements were intended to detect a crack 
in a frame assembly and prevent failure of a frame and subsequent loss 
of control of the helicopter.

Actions Since the NPRM Was Issued

    Since we issued the NPRM, we have revised the number of work-hours 
to replace the aircraft frames based upon the comments we received. 
This resulted in an overall increase in the cost of complying with the 
proposed AD. Since the economic burden is higher than that in the NPRM, 
we are reopening the comment period to allow the public the chance to 
comment on this new estimate.

Comments

    We gave the public the opportunity to comment on the NPRM. After 
our NPRM was published, we received the following comments from 
Sikorsky.

Request To Require Modification of the Frame Assembly

    Sikorsky requested that the AD require altering the transmission 
support frames in accordance with Sikorsky S-92 Alert Service Bulletin 
92-53-012, Basic Issue, dated February 10, 2014 (ASB 92-53-012), and 
Sikorsky Special Service Instructions No. 92-074-E, Revision E, dated 
April 9, 2014 (SSI 92-074-E). In support of its request, Sikorsky 
stated this modification largely improves the fatigue capability of the 
transmission support frames. Sikorsky also requested updating language 
in the preamble to reflect requiring the modification.
    We disagree. We determined that the alterations to the transmission 
support frames are not required to correct the unsafe condition.

Request To Remove the Daily Inspection

    Sikorsky requested that we remove the daily repetitive inspection 
requirement from the proposed AD. In support of this request, Sikorsky 
stated that the proposed AD's requirement to perform this same 
inspection every 150 hours time-in-service (TIS) would maintain the 
safety of the aircraft. Sikorsky further stated structural analysis 
reports substantiate the 150-hour inspection interval.
    We agree that the daily inspection requirement is not necessary to 
maintain the fleet's airworthiness. After reviewing data from 
Sikorsky's organization designation authorization supporting its life 
limit and continuing airworthiness projects, we determined that 
repeating the inspections every 150 hours would be adequate to detect 
and prevent an unsafe condition.

Request That the AD Reference the Maintenance Manual

    Sikorsky requested that the proposed AD reference the main 
transmission support structure inspection task in the Sikorsky 
maintenance manual for the 150-hour repetitive inspection. In support 
of this request, Sikorsky stated this task provides a complete, 
detailed procedure for the inspection requirements.
    We agree. We have revised the proposed AD to reference the task 
card as guidance for the 150-hour inspection.

Request To Delay Issuance of the Proposed AD

    Sikorsky requested that we delay issuing this proposed AD until 
after Sikorsky completes a project to increase the life limits of the 
forward STA 382 and aft STA 362 frame assemblies.
    We disagree. Because this unsafe condition could exist or develop 
on Sikorsky Model S-92A helicopters, the proposed actions are necessary 
to ensure safety of the U.S. fleet. Issuance of an AD is the 
appropriate method to correct the unsafe condition. Should completion 
of Sikorsky's certification project result in a corrective action that 
removes the unsafe condition, we might consider further rulemaking 
action.

Request To Correct Part Numbers

    Sikorsky requested that we correct two part numbers in Table 4 of 
the Required Actions. Specifically, Sikorsky

[[Page 66169]]

stated part number ``92070-02108-042'' should be ``92209-02108-042'' 
and part number ``92080-02108-103'' should be ``92209-02108-103.''
    We agree. We have revised the table accordingly.

Request To Add Serial Numbers to the Applicability

    Sikorsky requested that the proposed life limits only apply to 
helicopters with serial numbers 920006 through 920243. In support of 
this request, Sikorsky advised that starting with serial number 920244, 
helicopters were manufactured with an upgraded titanium frame 
configuration that is not affected by the proposed AD.
    We disagree. While production helicopters starting with serial 
number 920244 may not currently have the parts that are subject to the 
unsafe condition installed, operators are not required to maintain that 
configuration. Omitting the serial numbers allows the proposed AD to 
apply to any Model S-92A helicopter if a frame subject to the unsafe 
condition is later installed.

Request To Clarify Language Regarding Life Limit of Altered Parts

    Sikorsky requested that we clarify the wording of the 28,500-hour 
life limit for parts that are altered and changed to a new part number. 
Specifically, Sikorsky requested that we change ``28,500 hours TIS 
total (regardless of P/N)'' to ``28,500 hours TIS total from the 
original frame part number initial service date.''
    We disagree. The language in the proposed AD clearly states that 
this life limit applies regardless of whether the frame assembly part 
number changes.

Request To Revise the Compliance Cost

    Sikorsky requested that we revise the estimated costs of complying 
with the proposed AD. Specifically, Sikorsky advised that the number of 
hours to replace a frame has increased from 3,360 to 5,000, while the 
number of affected helicopters on the U.S. registry has decreased from 
80 to 50.
    We agree. We have revised the Costs of Compliance section 
accordingly.

Request To Revise Summary

    Sikorsky requested that we change the last sentence in SUMMARY, 
which identifies the unsafe condition, to be consistent with the 
language in the Unsafe Condition paragraph.
    We agree that Sikorsky's proposal provides more consistency. 
However, due to Administrative Committee of the Federal Register 
publishing requirements, the specific unsafe condition is no longer 
stated in SUMMARY. Thus, no change to this SNPRM is necessary.

Request To Update Contact Information

    Sikorsky requested that we update the email address for its 
Customer Service Engineering in both the preamble and the proposed AD.
    We agree and have made the requested changes.

Request To Clarify the Related Service Information Section

    Sikorsky requested that we revise the language in the Related 
Service Information section describing the actions in ASB 92-53-012 and 
SSI 92-074-E. Specifically, Sikorsky requests that we change 
``replacing the fasteners'' to ``removing steel doublers, cold-working 
holes, oversizing holes, trimming skin panels and reassembly with 
interference fit fasteners.'' In support, Sikorsky stated the 
recommended language would provide clarification.
    We agree. We have made the requested changes accordingly.

Request To Clarify the Differences Section

    Sikorsky requested that we clarify the Differences Between This 
Proposed AD and the Service Information section. Specifically, Sikorsky 
recommended adding ``by this AD'' to the sentence: ``Contacting 
Sikorsky would not be required.''
    We agree. We have revised the proposed AD accordingly.

Related Service Information

    Sikorsky issued S-92 Alert Service Bulletin (ASB) 92-53-008, Basic 
Issue, dated June 13, 2012 (ASB 92-53-008); S-92 ASB 92-53-009, Basic 
Issue, dated December 6, 2012 (ASB 92-53-009); and ASB 92-53-012. ASB 
92-53-008 provides procedures for a one-time inspection of the main 
transmission frames and beams for a crack, missing or loose fastener or 
collar, damage, deformation, and corrosion. ASB 92-53-009 specifies an 
inspection before the first flight of the day and a recurring 150-hour 
inspection of the interior and exterior surfaces of the upper flanges 
and beams. ASB 92-53-012 specifies altering the forward and aft 
transmission support frames by removing steel doublers, cold-working 
the holes, oversizing the holes, trimming skin panels and reassembling 
the parts with interference fit fasteners in accordance with SSI 92-
074-E. After this alteration, the parts are re-identified with a new 
part number. Sikorsky refers to this alteration as a service life 
extension program modification.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of these same type 
designs. Certain changes described above expand the scope of the NPRM. 
As a result, we have determined that it is necessary to reopen the 
comment period to provide additional opportunity for the public to 
comment on this SNPRM.

Proposed Requirements of This SNPRM

    This SNPRM would establish a life limit for certain part-numbered 
frame assemblies by removing from service any part that has reached or 
exceeded its new life limit. Frame assemblies that are altered under 
Sikorsky's service life extension program and re-identified with a new 
part number must be removed from service upon accumulating the life 
limit of the old part-number or within certain hours TIS since the 
alteration, whichever occurs first.
    This SNPRM also would require, within 150 hours TIS and thereafter 
at intervals not to exceed 150 hours TIS, inspecting STA 328 frame and 
STA 362 frame for a crack or loose fasteners. If there is a crack or 
loose fastener, this SNPRM would require repairing or replacing any 
cracked part and any loose fastener before further flight.

Differences Between This SNPRM and the Service Information

    The service information requires providing certain information to 
Sikorsky, and this proposed AD would not. The service information 
specifies performing a fluorescent penetrant inspection if there is a 
suspected crack and contacting Sikorsky if there is a crack, while this 
proposed AD would only require repairing or replacing any cracked part. 
Contacting Sikorsky would not be required by this proposed AD.

Costs of Compliance

    We estimate that this proposed AD would affect 50 helicopters of 
U.S. Registry. We estimate that operators may incur the following costs 
to comply with this proposed AD. Labor costs are estimated at $85 per 
work-hour. We estimate a minimal cost to establish and revise the life 
limit of the frame assembly. We estimate it would take 1 work-hour to 
inspect STA 328 and 362 frames. No parts would be needed for a total 
cost of $4,250 for the fleet for each inspection per inspection cycle. 
If a fastener is replaced, we estimate the cost to be minimal. If a 
frame is replaced, it would take 5,000 work-

[[Page 66170]]

hours and required parts would cost $296,000 for a total cost of 
$721,000 per helicopter.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. ``Subtitle VII: Aviation Programs'' 
describes in more detail the scope of the Agency's authority.
    We are 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

    We 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) Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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 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 (AD):

Sikorsky Aircraft Corporation Helicopters: Docket No. FAA-2016-8501; 
Product Identifier 2014-SW-042-AD.

(a) Applicability

    This AD applies to Model S-92A helicopters, certificated in any 
category, with a forward station (STA) 328 or aft STA 362 frame 
assembly with a part number (P/N) as shown in Table 1 to paragraph 
(e)(1), Table 2 to paragraph (e)(1), Table 3 to paragraph (e)(2), or 
Table 4 to paragraph (e)(2) of this AD.

(b) Unsafe Condition

    This AD defines the unsafe condition as a crack in a main 
transmission airframe support structure. This condition could result 
in failure of a main transmission frame and subsequent loss of 
control of the helicopter.

(c) Comments Due Date

    We must receive comments by February 11, 2019.

(d) Compliance

    You are responsible for performing each action required by this 
AD within the specified compliance time unless it has already been 
accomplished prior to that time.

(e) Required Actions

    (1) For helicopters with a frame assembly with a P/N shown in 
Table 1 to paragraph (e)(1) or Table 2 to paragraph (e)(1) of this 
AD, before further flight, remove from service any part that has 
reached or exceeded its new life limit. Forward STA 328 frame 
assemblies that are altered and changed to P/N 92070-20124-064, 
92070-20124-067, 92070-20127-045, 92070-20124-065, 92070-20124-047, 
or 92070-20127-046 must be removed from service upon accumulating 
12,000 hours TIS from the alteration or 28,500 hours TIS total 
(regardless of P/N) from the total original frame part number 
initial service date, whichever occurs first.

[[Page 66171]]

[GRAPHIC] [TIFF OMITTED] TP26DE18.011

    (2) For each frame assembly listed in Table 1 to paragraph 
(e)(1) or Table 4 to paragraph (e)(2) of this AD with 1,801 or more 
hours TIS, and for each frame assembly listed in Table 2 to 
paragraph (e)(1) or Table 3 to paragraph (e)(2) of this AD with 
1,301 or more hours TIS, within 150 hours TIS and thereafter at 
intervals not to exceed 150 hours TIS, do the following inspections. 
For guidance on performing these inspections, refer to Sikorsky S-
92A-AMM-000 Maintenance Manual Chapter 53-20-00, Task 53-20-00-210-
003, dated January 31, 2018:
    (i) Inspect the STA 328 frame and STA 362 frame between the left 
and right butt line (BL) 16.5 beams and inspect the area on the left 
and right BL 16.5 beams six inches on either side of the mounting 
pads for a crack and loose fasteners. If there is a loose fastener 
or a crack, repair or replace any cracked part and any loose 
fastener before further flight.
    (ii) Inspect the STA 328 and STA 362 outboard frames, left and 
right sides, from the BL 16.5 beam to water line 252.25 for a crack 
and loose fasteners. If there is a loose fastener or a crack, repair 
or replace any cracked part and any loose fastener before further 
flight.

[[Page 66172]]

[GRAPHIC] [TIFF OMITTED] TP26DE18.012

[GRAPHIC] [TIFF OMITTED] TP26DE18.013

(f) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Boston ACO Branch, FAA, may approve AMOCs for 
this AD. Send your proposal to: Kristopher Greer, Aviation Safety 
Engineer, Boston ACO Branch, Compliance and Airworthiness Division, 
1200 District Avenue, Burlington, Massachusetts 01803; telephone 
(781) 238-7799; email Kristopher.Greer@faa.gov.
    (2) For operations conducted under a 14 CFR part 119 operating 
certificate or under 14 CFR part 91, subpart K, we suggest that you 
notify your principal inspector, or lacking a principal inspector, 
the manager of the local flight standards district office or 
certificate holding district office before operating any aircraft 
complying with this AD through an AMOC.

(g) Additional Information

    Sikorsky S-92 Alert Service Bulletin (ASB) 92-53-008, Basic 
Issue, dated June 13, 2012; ASB 92-53-009, Basic Issue, dated 
December 6, 2012; ASB 92-53-012, Basic Issue, dated February 10, 
2014, and Sikorsky Special Service Instructions No. 92-074-E, 
Revision E, dated April 9, 2014, and Sikorsky S-92A-AMM-000 
Maintenance Manual, Chapter 53-20-00, Task 53-20-210-003, dated 
January 31, 2018, which are not incorporated by reference, contain 
additional information about the subject of this AD. For service 
information identified in this AD, contact Sikorsky Aircraft 
Corporation, Customer Service Engineering, 124 Quarry Road, 
Trumbull, CT 06611; telephone 1-800-Winged-S or 203-416-4299; email 
wcs_cust_service_eng.gr-sik@lmco.com. You may view this information 
at the FAA, Office of the Regional Counsel, Southwest Region, 10101 
Hillwood Pkwy., Room 6N-321, Fort Worth, TX 76177.

(h) Subject

    Joint Aircraft System Component (JASC) Code: 5311 Fuselage Main, 
Frame.

    Issued in Fort Worth, Texas, on December 13, 2018.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2018-27713 Filed 12-21-18; 8:45 am]
 BILLING CODE 4910-13-P