81 FR 85124 - Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration

Federal Register Volume 81, Issue 227 (November 25, 2016)

We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation Model S-76D helicopters. This AD requires revising the rotorcraft flight manual (RFM) to prohibit Barometric Altitude Hold (ALT) mode beyond a certain rate of climb or descent. This AD is prompted by a report of the autopilot being unable to maintain level flight during certain flight conditions. The actions specified by this AD are intended to prevent a significant pilot workload increase, pilot disorientation, and subsequent loss of control of the helicopter.

[Federal Register Volume 81, Number 227 (Friday, November 25, 2016)]
[Rules and Regulations]
[Pages 85124-85126]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2016-27771]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-9281; Directorate Identifier 2016-SW-033-AD; 
Amendment 39-18717; AD 2016-23-10]
RIN 2120-AA64


Airworthiness Directives; Sikorsky Aircraft Corporation 
Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: We are adopting a new airworthiness directive (AD) for 
Sikorsky Aircraft Corporation Model S-76D helicopters. This AD requires 
revising the rotorcraft flight manual (RFM) to prohibit Barometric 
Altitude Hold (ALT) mode beyond a certain rate of climb or descent. 
This AD is prompted by a report of the autopilot being unable to 
maintain level flight during certain flight conditions. The actions 
specified by this AD are intended to prevent a significant pilot 
workload increase, pilot disorientation, and subsequent loss of control 
of the helicopter.

DATES: This AD becomes effective December 12, 2016.
    The Director of the Federal Register approved the incorporation by 
reference of a certain document listed in this AD as of December 12, 
2016.
    We must receive comments on this AD by January 24, 2017.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Docket: Go to http://www.regulations.gov. Follow the online instructions for sending your 
comments electronically.
     Fax: 202-493-2251.
     Mail: Send comments to the U.S. Department of 
Transportation, Docket Operations, M-30, West Building Ground Floor, 
Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590-0001.
     Hand Delivery: Deliver to the ``Mail'' address between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.

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-
9281; or in person at the Docket Operations Office between 9 a.m. and 5 
p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this AD, any incorporated-by-reference service information, 
the economic evaluation, any comments received, and other information. 
The street address for the Docket Operations Office (telephone 800-647-
5527) is in the ADDRESSES section. Comments will be available in the AD 
docket shortly after receipt.
    For service information identified in this final rule, contact 
Sikorsky Aircraft Corporation, Customer Service Engineering, 124 Quarry 
Road, Trumbull, CT 06611; telephone 1-800-Winged-S or 203-416-4299; 
email: [email protected]. You may review the 
referenced service information at the FAA, Office of the Regional 
Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N-321, Fort 
Worth, TX 76177. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2016-
9281.

FOR FURTHER INFORMATION CONTACT: John Coffey, Flight Test Engineer, 
Boston Aircraft Certification Office, Engine & Propeller Directorate, 
FAA, 1200 District Avenue, Burlington, Massachusetts 01803; telephone 
(781) 238-7173; email [email protected].

SUPPLEMENTARY INFORMATION: 

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety, and we did not provide you with notice and an opportunity to 
provide your comments prior to it becoming effective. However, we 
invite you to participate in this rulemaking by submitting written 
comments, data, or views. We also invite comments relating to the 
economic, environmental, energy, or federalism impacts that resulted 
from adopting this AD. The most helpful comments reference a specific 
portion of the AD, explain the reason for any recommended change, and 
include supporting data. To ensure the docket does not contain 
duplicate comments, commenters should send only one copy of written 
comments, or if comments are filed electronically, commenters should 
submit them only one time. We will file in the docket all comments that 
we receive, as well as a report summarizing each substantive public 
contact with FAA personnel concerning this rulemaking during the 
comment period. We will consider all the comments we receive and may 
conduct additional rulemaking based on those comments.

[[Page 85125]]

Discussion

    We are adopting a new AD for Sikorsky Aircraft Corporation Model S-
76D helicopters. This AD requires revising the ``Automatic Flight 
Control System'' section of the RFM Limitations by inserting a 
limitation prohibiting the use of the ALT mode during a rate of climb 
or descent greater than 1,000 feet/minute (fpm). This AD is prompted by 
a report of the autopilot being unable to maintain level flight in 
certain flight conditions. To explore the report further, the FAA 
conducted additional flight tests, which revealed that when the 
helicopter is at density altitudes greater than 13,000 feet and the 
autopilot is commanding either a climb or descent at rates greater than 
1,000 fpm, and the ALT HOLD mode is then engaged, the autopilot is 
unable to maintain level flight when large collective inputs are 
applied. These conditions saturate the stability augmentation system 
(SAS) actuators, subsequently providing insufficient control response 
during the collective input. As a result, the helicopter may experience 
a dynamic response with roll excursions greater than 50 degrees of bank 
angle and yaw excursions greater than 70 degrees of heading. This 
condition could result in a significant increase in pilot workload, 
pilot disorientation, and loss of control of the helicopter.

FAA's Determination

    We are issuing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other helicopters of this same type 
design.

Related Service Information Under 1 CFR Part 51

    Sikorsky issued S-76D RFM SA S76D-RFM-000, Temporary Revision No. 
7, approved May 19, 2016, which revises the Limitations section by 
prohibiting ALT mode during a rate of climb or descent greater than 
1,000 fpm.
    This service information is reasonably available because the 
interested parties have access to it through their normal course of 
business or by the means identified in the ADDRESSES section.

AD Requirements

    This AD requires, within 10 hours time-in-service (TIS), revising 
the Limitations section of the RFM by inserting a limitation stating 
that ALT mode shall not be engaged with a rate of climb or descent 
greater than 1,000 fpm.

Interim Action

    We consider this AD to be an interim action. The design approval 
holder is planning to develop a modification that will address the 
unsafe condition identified in this AD. Once this modification is 
developed, approved, and available, we might consider additional 
rulemaking.

Costs of Compliance

    We estimate that this AD will affect 12 helicopters of U.S. 
Registry. We estimate that operators may incur the following costs in 
order to comply with this AD. At an average labor rate of $85 per work-
hour, revising the RFM will require 0.5 work-hour, for cost of about 
$43 per helicopter and $516 for the U.S. fleet.

FAA's Justification and Determination of the Effective Date

    Providing an opportunity for public comments prior to adopting 
these AD requirements would delay implementing the safety actions 
needed to correct this known unsafe condition. Therefore, we find that 
the risk to the flying public justifies waiving notice and comment 
prior to the adoption of this rule because the unsafe condition can 
adversely affect control of the helicopter, and the required corrective 
actions must be accomplished within 10 hours TIS.
    Since an unsafe condition exists that requires the immediate 
adoption of this AD, we determined that notice and opportunity for 
public comment before issuing this AD are impracticable and contrary to 
the public interest and that good cause exists for making this 
amendment effective in less than 30 days.

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 AD will not have federalism implications 
under Executive Order 13132. This AD will not have a substantial direct 
effect on the States, on the relationship between the national 
Government and the States, or on the distribution of power and 
responsibilities among the various levels of government.
    For the reasons discussed, I certify that this AD:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866;
    2. Is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979);
    3. Will not affect intrastate aviation in Alaska to the extent that 
it justifies making a regulatory distinction; 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.
    We prepared an economic evaluation of the estimated costs to comply 
with this AD and placed it in the AD docket.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701.


Sec.  39.13  [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive (AD):

2016-23-10 Sikorsky Aircraft Corporation: Amendment 39-18717; Docket 
No. FAA-2016-9281; Directorate Identifier 2016-SW-033-AD.

(a) Applicability

    This AD applies to Model S-76D helicopters, certificated in any 
category.

 (b) Unsafe Condition

    This AD defines the unsafe condition as an inability of the 
autopilot to maintain level flight. This condition could result in a 
significant increase in pilot workload, pilot disorientation, and 
subsequent loss of control of the helicopter.

[[Page 85126]]

 (c) Effective Date

    This AD becomes effective December 12, 2016.

 (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

    Within 10 hours time-in-service, revise Section 1 Limitations, 
``Automatic Flight Control System'' section, of the Rotorcraft 
Flight Manual by one of the following methods:
    (1) Insert Sikorsky S-76D SA S76D-RFM-000, Temporary Revision 
No. 7, approved May 19, 2016; or
    (2) Insert a copy of this AD; or
    (3) Make pen-and-ink changes to add the information in Figure 1 
to paragraph (e) of this AD.
[GRAPHIC] [TIFF OMITTED] TR25NO16.000

 (f) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Boston Aircraft Certification Office, FAA, may 
approve AMOCs for this AD. Send your proposal to: John Coffey, 
Flight Test Engineer, Boston Aircraft Certification Office, Engine & 
Propeller Directorate, FAA, 1200 District Avenue, Burlington, 
Massachusetts 01803; telephone (781) 238-7173; email 
[email protected].
    (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) Subject

    Joint Aircraft Service Component (JASC) Code: 2210, Autopilot 
System.

 (h) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference of the service information listed in this 
paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Sikorsky S-76D SA S76D-RFM-000, Temporary Revision No. 7, 
approved May 19, 2016.
    (ii) Reserved.
    (3) For Sikorsky 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: [email protected].
    (4) You may view this service information at FAA, Office of the 
Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N-
321, Fort Worth, TX 76177. For information on the availability of 
this material at the FAA, call (817) 222-5110.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, call (202) 741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Fort Worth, Texas, on November 4, 2016.
Lance T. Gant,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2016-27771 Filed 11-23-16; 8:45 am]
 BILLING CODE 4910-13-P