[4910-13-P]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2024-1886; Project Identifier AD-2023-01018-R]
RIN 2120-AA64
Airworthiness Directives; Robinson Helicopter Company 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
Robinson Helicopter Company (Robinson Helicopter) Model R22 Beta, R22 Mariner,
R44, and R44 II helicopters with a certain governor controller installed. This proposed
AD was prompted by reports of engine governor failure, which was a result of water
intrusion inside of the governor controller. This proposed AD would require removing
certain governor controllers from service and installing a part eligible for installation.
This proposed AD would also prohibit installing certain governor controllers on any
helicopter. 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 [INSERT DATE 45
DAYS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER].
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. FAA2024-1886; 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.
Material Incorporated by Reference:
• For Robinson Helicopter service information, contact Robinson Helicopter
Company, Technical Support Department, 2901 Airport Drive, Torrance, CA 90505;
phone (310) 539-0508; fax (310) 539-5198; email ts1@robinsonheli.com; or at
robinsonheli.com.
• You may view this service information at the FAA, Office of the Regional
Counsel, Southwest Region, 10101 Hillwood Parkway, Room 6N-321, Fort Worth, TX
76177. For information on the availability of this material at the FAA, call (817) 2225110.
Other Related Service Information: For Robinson service information identified in this
NPRM, contact Robinson Helicopter Company at its contact information under Material
Incorporated by Reference above.
FOR FURTHER INFORMATION CONTACT: Eric Moreland, Aviation Safety
Engineer, FAA, 3960 Paramount Boulevard, Lakewood, CA 90712; phone: (562) 6275364; email: eric.r.moreland@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-2024-1886; Project Identifier AD-2023-01018-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 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 Eric Moreland,
Aviation Safety Engineer, FAA, 3960 Paramount Boulevard, Lakewood, CA 90712;
phone: (562) 627-5364; email: eric.r.moreland@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 has received three reports of governor controller failures involving
Robinson Helicopter Model R22 Beta and R44 II helicopters. These failures resulted in
three underspeed or overspeed events, and two of these events resulted in hard landings
which caused significant damage to the helicopters. Each of these separate incidents
occurred after significant rainfall where the helicopter was exposed to those weather
conditions. Prior to these governor controller failures, several operators notified Robinson
Helicopter of a malfunction of the governor controller. Subsequent investigation revealed
evidence of water spotting inside of these governor controllers. Testing involving the
application of water to the electronics of a governor controller confirmed that these
conditions result in this malfunction. As a result of this investigation, it has been

determined that the root cause for these malfunctions is water intrusion in the circuit
board of the governor controller. In light of this, Robinson Helicopter issued service
bulletins which specify exchanging the existing governor controller with a governor
which provides additional moisture protection. Since the affected parts may also be
installed on Robinson Helicopter Model R22 Mariner and R44 helicopters, those model
helicopters are also affected by the unsafe condition. The affected parts cannot be
installed on Robinson Helicopter Model R22 and R22 Alpha helicopters, so those model
helicopters are not affected by the unsafe condition. The unsafe condition, if not
addressed, could result in loss of engine speed governing such as an engine overspeed or
underspeed condition, and subsequent unexpected loss of power during critical phases of
flight and landing.
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 Robinson Helicopter R22 Service Bulletin SB-121 and
Robinson Helicopter R44 Service Bulletin SB-114, each dated June 28, 2023 (SB-121
and SB-114). This service information specifies procedures for removing governor
controller part number (P/N) D270-1, Revision A thru E, and replacing it with governor
controller P/N D270-1, Revision F (or subsequent).
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.
Other Related Service Information
The FAA also reviewed Robinson R22 and R44 Engine Monitoring Unit (EMU)
Technician’s PC Software Guide, dated Oct 9, 2020. This service information provides
information to program the new EMU ID for the governor controller.

Proposed AD Requirements in this NPRM
This proposed AD would require removing any governor controller P/N D270-1,
Revision A thru E inclusive, from service and installing a governor controller P/N D2701, Revision F or later approved revision. This proposed AD would also prohibit installing
governor controller P/N D270-1, Revision A through E inclusive, on any helicopter.
Costs of Compliance
The FAA estimates that this AD, if adopted as proposed, would affect 140
helicopters of U.S. registry. The FAA estimates the following costs to comply with this
proposed AD. Labor costs are estimated at $85 per work-hour.
Replacing the governor controller would take approximately 2 work-hours and
parts would cost approximately $1,800 for an estimated cost of $1,970 per helicopter and
$275,800 for the U.S. fleet.
Differences Between this Proposed AD and the Service Information
The service information applies to Robinson Helicopter Model R22-series and
R44-series helicopters with a certain P/N D270-1 governor controllers installed and also
identifies which serial-numbered helicopters the affected parts were factory installed on,
whereas this proposed AD would apply to all Robinson Helicopter Model R22 Beta, R22
Mariner, R44, and R44 II helicopters with a certain P/N D270-1 governor controllers
installed. This proposed AD would require accomplishing certain actions specified in SB121 or SB-114, as applicable to your helicopter model, except the procedures in
paragraph 4. of SB-121 and SB-114 must be accomplished by persons authorized under
14 CFR 43.3., instead of “an appropriately rated person.”
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
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:
Robinson Helicopter Company: Docket No. FAA-2024-1886; Project Identifier AD2023-01018-R.

(a) Comments Due Date
The FAA must receive comments on this airworthiness directive (AD) by
[INSERT DATE 45 DAYS AFTER DATE OF PUBLICATION IN THE FEDERAL
REGISTER].
(b) Affected ADs
None.
(c) Applicability
This AD applies to all Robinson Helicopter Company Model R22 Beta, R22
Mariner, R44, and R44 II helicopters, certificated in any category, with a governor
controller part number (P/N) D270-1, Revision A through E inclusive, installed.
(d) Subject
Joint Aircraft System Component (JASC) Code: 2700, Flight Control System.
(e) Unsafe Condition
This AD was prompted by reports of engine governor failures caused by water
intrusion. The FAA is issuing this AD to prevent engine governor failures. The unsafe
condition, if not addressed, could result in loss of engine speed governing such as an
engine overspeed or underspeed condition, and subsequent unexpected loss of power
during critical phases of flight and landing.
(f) Compliance
Comply with this AD within the compliance times specified, unless already done.
(g) Required Actions
(1) Within 90 days after the effective date of this AD, remove the governor
controller from service and install a governor controller P/N D270-1, Revision F or later
approved revision by following the Compliance Procedure, paragraphs 2. though 5., of
Robinson Helicopter Company R22 Service Bulletin SB-121 or R44 Service Bulletin SB114, each dated June 28, 2023 (SB-121 or SB-114), as applicable to your helicopter
model, except the procedures in paragraph 4. of SB-121 and SB-114 must be
accomplished by persons authorized under 14 CFR 43.3.
(2) As of the effective date of this AD, do not install any governor controller P/N
D270-1, Revision A through E inclusive, on any helicopter.

(h) Alternative Methods of Compliance (AMOCs)
(1) The Manager, West Certification 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 West Certification Branch, send it to the attention of the person identified
in paragraph (i) of this AD. Information may be emailed to: 9-ANM-LAACO-AMOCREQUESTS@faa.gov.
(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) Additional Information
For more information about this AD, contact Eric Moreland, Aviation Safety
Engineer, FAA, 3960 Paramount Boulevard, Lakewood, CA 90712; phone: (562) 6275364; email: eric.r.moreland@faa.gov.
(j) Material Incorporated by Reference
(1) The Director of the Federal Register approved the incorporation by reference
(IBR) 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) Robinson Helicopter Company R22 Service Bulletin SB-121, dated June 28,
2023.
(ii) Robinson Helicopter Company R44 Service Bulletin SB-114, dated June 28,
2023.
(3) For Robinson Helicopter Company service information, contact Robinson
Helicopter Company, Technical Support Department, 2901 Airport Drive, Torrance, CA
90505; phone (310) 539-0508; fax (310) 539-5198; email ts1@robinsonheli.com; or at
robinsonheli.com.

(4) You may view this service information at the FAA, Office of the Regional
Counsel, Southwest Region, 10101 Hillwood Parkway, Room 6N-321, Fort Worth, TX
76177. For information on the availability of this material at the FAA, call (817) 2225110.
(5) You may view this material at the National Archives and Records
Administration (NARA). For information on the availability of this material at NARA,
visit www.archives.gov/federal-register/cfr/ibr-locations or email
fr.inspection@nara.gov.
Issued on July 10, 2024.

James D. Foltz,
Deputy Director, Compliance & Airworthiness Division,
Aircraft Certification Service.
[FR Doc. 2024-15707 Filed: 7/16/2024 8:45 am; Publication Date: 7/17/2024]