DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2020-0320; Project Identifier 2019-CE-011-AD; Amendment
39-21248; AD 2020-19-06]
Airworthiness Directives; McCauley Propeller Systems
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
SUMMARY: The FAA is adopting a new airworthiness directive (AD)
certain model McCauley Propeller Systems (McCauley) governors installed
on airplanes. This AD was prompted by reports of an unapproved variant
McCauley idler gear bearing, part number (P/N) A-20028, that could be
installed in the affected governors. This AD requires replacing the
governor with a governor that is eligible for installation. The FAA is
issuing this AD to address the unsafe condition on these products.
DATES: This AD is effective November 3, 2020.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of November 3,
ADDRESSES: For service information identified in this final rule,
contact McCauley Propeller Systems, One Cessna Boulevard, P.O. Box
7704, Wichita, Kansas 67277; telephone: (800) 621-7767 or (316) 831-
4021; email: firstname.lastname@example.org; internet: https://mccauley.txtav.
com. You may view this service information at the FAA,
Airworthiness Products Section, Operational Safety Branch, 901 Locust,
Kansas City, Missouri 64106. For information on the availability of
this material at the FAA, call (816) 329-4148. It is also available on
the internet at https://www.regulations.gov by searching for and
locating Docket No. FAA-2020-0320.
Examining the AD Docket
You may examine the AD docket on the internet at https://www.regulations.
gov by searching for and locating Docket No. FAA-2020-
0320; 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 final rule, the regulatory evaluation, any comments received, and
other information. The address for Docket Operations U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Thomas Teplik, Aerospace Engineer,
Wichita ACO Branch, 1801 Airport Road, Room 100, Wichita, Kansas 67209;
telephone: (316) 946-4196; fax: (316) 946-4107; email:
email@example.com or Wichita-COS@faa.gov.
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to certain model McCauley
Propeller Systems (McCauley) governors installed on airplanes. The NPRM
published in the Federal Register on April 7, 2020 (85 FR 19399). The
NPRM was prompted by reports from McCauley that an unapproved variant
idler gear bearing, P/N A-20028, was installed on certain governors
during production between January 31, 2017, and September 27, 2018, and
may have been installed on governors in service after January 31, 2017.
The unapproved variant of the idler gear bearing does not conform to
McCauley drawing requirements.
All models of McCauley governors have an idler gear bearing with P/
N A-20028 installed; however, the unapproved variant of the bearing can
be identified by part marking ``BA 59.'' The non-conforming idler gear
bearing could have also been included in the idler gear assembly (idler
gear and bearing), P/N A-20107, or the governor overhaul kit, P/N PL-
20233 or PL-20234.
The non-conformity of the bearing may cause premature failure of
the idler gear bearing. Early symptoms that the idler gear bearing may
fail include inability of the governor to hold the selected RPM,
hunting, surging, etc. An investigation identified 23 occurrences of
airplane operation problems related to erratic governor behavior that
may have resulted from the unapproved idler gear bearing.
The NPRM proposed to require replacing an affected governor with a
governor eligible for installation. The FAA is issuing this AD to
prevent failure of the idler gear bearing, which could result in
failure of the governor, loss of propeller pitch control, engine and
propeller over speed, engine oil contamination, and loss of airplane
The FAA gave the public the opportunity to participate in
developing this final rule. The following presents the comments
received on the NPRM and the FAA's response to each comment.
The Civil Aviation Safety Authority (CASA) of Australia, David
Paynter, and Chartair Pty Ltd supported the NPRM.
Request To Clarify the Applicability
CASA, David Paynter, and Chartair Pty Ltd requested the FAA clarify
the applicability with respect to the idle gearing bearings affected by
the unsafe condition.
CASA advised of similar incidents of premature failure in idler
gear bearings identified by part marking ``SCE 59'' and asked whether
the FAA has determined that the unsafe condition exists or can develop
in idler gear bearings other than those identified with ``BA 59.''
David Paynter expressed concern with governors that have ``SCE 59''
bearings or bearings with ``BA 59'' that do not have any country of
origin stamped on them. Chartair Pty Ltd stated it has experienced
bearing failures outside of the range identified in the NPRM. David
Paynter and Chartair Pty Ltd requested the FAA change the AD to include
these additional bearings.
The FAA disagrees. The A-20028 bearing identified with ``BA 59'' is
an unapproved bearing that does not conform to McCauley drawing
requirements. Although the FAA is aware of failures of bearings other
than those stamped with ``BA 59'', these bearings do not demonstrate
the same unsafe condition as identified in this AD. The FAA will
continue to monitor McCauley governor field reports for issues
involving bearings other than those stamped with ``BA 59''.
The FAA did not make changes to this AD as a result of these
Request To Clarify the Required Actions
The Aircraft Owners and Pilots Association (AOPA) requested the FAA
clarify paragraph (f), Compliance, of the NPRM. AOPA stated that the
proposed language in paragraph (f) of the proposed AD to replace the
governor with a governor eligible for installation can be misleading
and imply that the governor must be replaced with a new or overhauled
governor regardless of the status of the existing governor.
The FAA disagrees. Paragraph (f) of this AD requires compliance,
unless already done. Thus, the AD allows
operators to take credit for replacing the governor with a governor
eligible for installation if done before the effective date of the AD.
If the existing governor does not have an idler gear bearing with a
part marking ``BA 59'', then compliance is already done.
No changes to this AD are necessary based on this comment.
Request To Clarify the Installation Prohibition
AOPA requested the FAA clarify the wording in paragraph (h), Parts
Installation Prohibition, of the NPRM. AOPA stated the language does
not convey whether replacing the affected idle gear bearing in the
governor terminates the AD.
The FAA disagrees. This AD does not require repetitive actions;
therefore, terminating action is inappropriate. The installation
prohibition ensures that affected governors will not be replaced with
part that has the unsafe condition. Once the affected governor is
replaced in accordance with the requirements of this AD, no further
action is required. The FAA did not make changes to this AD as a result
of this comment.
The FAA reviewed the relevant data, considered the comments
received, and determined that air safety and the public interest
require adopting this final rule with the changes described previously.
The FAA has determined that these changes:
Are consistent with the proposal in the NPRM for
addressing the unsafe condition; and
Do not add any burden upon the public than was already
proposed in the NPRM.
Related Service Information Under 1 CFR Part 51
The FAA reviewed McCauley Alert Service Bulletin No. ASB273C, dated
January 30, 2019. The service bulletin contains model and serial number
information to identify the affected governors. The service bulletin
also contains procedures for removing the governor from the engine,
inspecting the governor for the unapproved variant idler gear bearing,
replacing the idler gear bearing or idler gear assembly if necessary,
overhauling the governor if necessary, and installing a governor on the
engine. 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.
Costs of Compliance
The FAA estimates that this AD affects 2,500 governors as installed
in airplanes of U.S. registry.
The FAA estimates the following costs to comply with this AD:
|Remove affected governor
||1 work-hour x $85 per hour =
|Install a governor
||1 work-hour x $85 per hour =
||See table below
An operator has the option to pay
a service center to inspect their
existing governor and replace the idler gear bearing if necessary or
pay to have their existing governor overhauled. An operator has the
option to purchase a factory new governor or an overhauled governor, a
feathering/syncing governor or a non-feathering/syncing governor. The
FAA has no way of knowing what option an operator may take to obtain a
governor eligible for installation. Therefore, the FAA has no way of
determining the parts cost on U.S. operators. The following represents
the estimated parts cost associated with obtaining a governor.
Cost for an Eligible Governor
|Type of governor
||Cost of governor
|Factory new non-feathering/non-syncing
|Factory new feathering/syncing
|Overhaul of existing non-feathering/non-syncing
|Overhaul of existing feathering/syncing
According to the manufacturer, some
of the costs of this AD may be
covered under warranty, thereby reducing the cost impact on affected
individuals. The FAA does not control warranty coverage for affected
individuals. As a result, the FAA has included all costs in this cost
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.
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 govement.
For the reasons discussed above, I certify that this AD:
(1) Is not a ``significant regulatory action'' under Executive
(2) Will not affect intrastate aviation in Alaska, and
(3) 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
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
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]
2. The FAA amends Sec. 39.13 by adding the following new airworthiness