Proposed Rule2026-07714
Special Conditions: Skyryse, Robinson Helicopter Company Model R66 Helicopter; Flight Control System Annunciation of Control
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
April 21, 2026
Issuing agencies
Transportation DepartmentFederal Aviation Administration
Abstract
This action proposes special conditions for the Robinson Helicopter Company (Robinson) Model R66 helicopter. This helicopter, as modified by Skyryse, will have a novel or unusual design feature when compared to the state of technology envisioned in the airworthiness standards for normal category helicopters. This design feature replaces the mechanical flight controls with a digital fly-by-wire (FBW) system. 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.
Full Text
<html>
<head>
<title>Federal Register, Volume 91 Issue 76 (Tuesday, April 21, 2026)</title>
</head>
<body><pre>
[Federal Register Volume 91, Number 76 (Tuesday, April 21, 2026)]
[Proposed Rules]
[Pages 21268-21269]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-07714]
========================================================================
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. 91, No. 76 / Tuesday, April 21, 2026 /
Proposed Rules
[[Page 21268]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 27
[Docket No. FAA-2025-5245; Notice No. 27-26-01-SC]
Special Conditions: Skyryse, Robinson Helicopter Company Model
R66 Helicopter; Flight Control System Annunciation of Control
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed special conditions.
-----------------------------------------------------------------------
SUMMARY: This action proposes special conditions for the Robinson
Helicopter Company (Robinson) Model R66 helicopter. This helicopter, as
modified by Skyryse, will have a novel or unusual design feature when
compared to the state of technology envisioned in the airworthiness
standards for normal category helicopters. This design feature replaces
the mechanical flight controls with a digital fly-by-wire (FBW) system.
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 June 5, 2026.
ADDRESSES: Send comments identified by Docket No. FAA-2025-5245 using
any of the following methods:
Federal eRegulations Portal: Go to <a href="http://www.regulations.gov">www.regulations.gov</a> 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
<a href="http://www.regulations.gov">www.regulations.gov</a> 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: Johannes VanHoudt, Product Policy
Management, AIR-62B, Technical Policy Branch, Policy and Standards
Division, Aircraft Certification Service, Federal Aviation
Administration, 901 Locust, Kansas City, MO 64106; telephone (816) 329-
4144; email <a href="/cdn-cgi/l/email-protection#107a7f787e3e773e66717e3e787f657464507671713e777f66"><span class="__cf_email__" data-cfemail="c9a3a6a1a7e7aee7bfa8a7e7a1a6bcadbd89afa8a8e7aea6bf">[email protected]</span></a>.
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 <a href="http://www.regulations.gov">www.regulations.gov</a>, 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 For Further
Information 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 April 10, 2023, Skyryse applied for a supplemental type
certificate (STC) for replacing the current mechanical primary flight
controls with an FBW flight control system (FCS) in the Robinson Model
R66 helicopter. The Robinson Model R66 helicopter, currently approved
under Type Certificate No. R00015LA, is a single engine normal category
rotorcraft with a maximum takeoff weight of 2,700 pounds and a maximum
seating capacity of five passengers. The Model R66 is a single pilot
helicopter approved for day and night operations under visual flight
rules (VFR) only.
Section 27.695 was issued in 1964 for rotorcraft with rudimentary
mechanical systems. The state of technology at that time provided no
basis for a digital replacement. Skyryse is proposing to replace the
current mechanical primary flight controls on the Model R66 helicopter
with a digital FBW FCS. Because of the loss of pilot awareness that
would have been provided by mechanical system feedback to the cyclic,
an annunciation requirement is necessary through these special
conditions.
Type Certification Basis
Under the provisions of 14 CFR 21.101, Skyryse must show that the
[[Page 21269]]
Robinson Model R66 helicopter, as changed, continues to meet the
applicable provisions of the regulations incorporated by reference in
Type Certificate No. R00015LA or the applicable regulations in effect
on the date of application for the change.
If the Administrator finds that the applicable airworthiness
regulations (i.e., 14 CFR part 27) do not contain adequate or
appropriate safety standards for the Robinson Model R66 helicopter
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 an STC 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 Robinson Model R66 helicopter must comply with the
fuel-vent and exhaust-emission requirements of 14 CFR part 34, and the
noise-certification requirements of 14 CFR part 36.
The FAA issues special conditions, as defined in 14 CFR 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 Robinson Model R66 helicopter would incorporate the following
novel or unusual design feature:
A primary FCS that replaces the mechanical cyclic and collective
with a FBW FCS. Skyryse applied for a supplemental type certificate for
a system with aircraft-agnostic flight automation technology, the
SkyOS, in Robinson Model R66 rotorcraft. The flight control inputs from
this FBW system will replace the tactical feedback from pushrods with a
position calculated by a computer. The SkyOS does not modify the
engine, main rotor, tail rotor, or physical travel limits of the flight
control surfaces.
Discussion
The 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. The proposed special conditions are required
to address the gap in the regulation that was created by the
replacement of mechanical primary flight control with digital controls.
Section 27.695 is based on the ability of the pilot to manage control
of the rotorcraft with tactile feedback, which does not exist in the
proposed FBW design. As such, to provide the same level of safety,
these proposed special conditions would require a display of the
commanded positions of the primary flight controls and any information
regarding the FBW system state of operation.
Applicability
As discussed above, these proposed special conditions are
applicable to the model for which they are issued. Should the applicant
apply for an STC to modify any other model included on the same type
certificate to incorporate the same novel or unusual design feature,
these special conditions would apply to the other model as well.
Conclusion
This action affects only a certain novel or unusual design feature
on one helicopter model. 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 27
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 Federal Aviation Administration proposes the
following special conditions as part of the type certification basis
for the Robinson Helicopter Company Model R66 helicopter, as modified
by Skyryse.
Flight Control Systems
The flight control system functions, controls, indications, and
alerts must be designed to minimize flightcrew errors and confusion
concerning operation of the flight control system. This includes any
degraded functions required for continued safe flight and landing.
Means must be provided to indicate the current mode of operation to the
pilot. The controls and indications must be grouped and presented to
the pilot in a format that clearly defines the flight control system
functions. The displayed information must be visible to the flightcrew
under all expected lighting conditions.
Issued in Fort Worth, Texas, on April 16, 2026.
Jorge R. Castillo,
Manager, Technical Policy Branch, Policy and Standards Division,
Aircraft Certification Service.
[FR Doc. 2026-07714 Filed 4-20-26; 8:45 am]
BILLING CODE 4910-13-P
</pre><script data-cfasync="false" src="/cdn-cgi/scripts/5c5dd728/cloudflare-static/email-decode.min.js"></script></body>
</html>Indexed from Federal Register on April 21, 2026.
This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.