DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2020-0781; Product Identifier 2018-CE-045-AD]
Airworthiness Directives; Mitsubishi Heavy Industries, Ltd. Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
SUMMARY: The FAA proposes to supersede Airworthiness Directive
16-20, which applies to all Mitsubishi Model MU-2B, MU-2B-10, MU-2B-15,
MU-2B-20, MU-2B-25, MU-2B-26, MU-2B-30, MU-2B-35, and MU-2B-36
airplanes. AD 75-16-20 requires repetitive inspections of the propeller
pitch control (PPC) lever for security and proper rigging. Since the
FAA issued AD 75-16-20, the FAA received additional reports of the PPC
lever linkage disconnecting at the engine. In addition, Mitsubishi has
type certificated additional airplanes that are subject to the unsafe
condition. This proposed AD would require modification and repetitive
inspections of the PPC lever linkage. 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 October
ADDRESSES: You may send comments, using the procedures found in
11.43 and 11.45, by any of the following methods:
Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow
instructions for submitting comments.
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.
For service information identified in this NPRM, contact Mitsubishi
Heavy Industries America, Inc., c/o Turbine Aircraft Services, Inc.,
4550 Jimmy Doolittle Drive, Addison, Texas 75001; telephone: (972) 248-
3108, ext. 209; fax: (972) 248-3321; internet: https://mu-2aircraft.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.
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-2020-0781;
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. Comments will be
available in the AD docket shortly after receipt.
FOR FURTHER INFORMATION CONTACT: John Turner, Aerospace Engineer,
Fort Worth ACO Branch, 10101 Hillwood Parkway, Fort Worth, Texas 76177;
telephone: (817) 222-4508; fax: (817) 222-5245; email:
The FAA invites 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-2020-0781;
Product Identifier 2018-CE-045-AD" 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 proposed AD based on those comments.
Except for Confidential Business Information 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 https://www.
regulations.gov, including any personal information you provide.
The FAA will also post a report summarizing each substantive verbal
contact received about this proposed AD.
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
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 John Turner, Aerospace Engineer, FAA, Fort Worth
ACO Branch, 10101 Hillwood Parkway, Fort Worth, Texas 76177; telephone:
(817) 222-4508; fax: (817) 222-5245; email: email@example.com. Any
commentary that the FAA receives which is not specifically designated
as CBI will be placed in the public docket for this rulemaking.
The FAA issued AD 75-16-20, Amendment 39-2294 (40 FR 31751, July
29, 1975) ("AD 75-16-20"), for all Mitsubishi Heavy Industries, Ltd.
(Mitsubishi) Models MU-2B, MU-2B-10, MU-2B-15, MU-2B-20, MU-2B-25, MU-
2B-26, MU-2B-30, MU-2B-35, and MU-2B-36 airplanes. AD 75-16-20 requires
repetitively inspecting the PPC lever for security and proper rigging.
AD 75-16-20 resulted from reports of the PPC lever linkage
disconnecting from the engine. The FAA issued AD 75-16-20 to
prevent separation of the PPC lever, which could lead to the
inability to control the propeller pitch with the power lever in the
cockpit and subsequent loss of control of the engine power settings.
Actions Since AD 75-16-20 Was Issued
Since the FAA issued AD 75-16-20, the FAA received reports of the
PPC lever linkage disconnecting at the engine, which resulted in the
inability to control the propeller pitch with the power lever in the
cockpit. This condition, if uncorrected, could lead to loss of control
of the engine power settings. In addition, Mitsubishi developed a
secondary retention feature to secure the PPC. To correct this unsafe
condition, the Japan Civil Aviation Bureau (JCAB), which is the
aviation authority for Japan, issued JCAB AD No. TCD-8678-2016, dated
February 5, 2016 (referred to after this as the mandatory continuing
airworthiness information or "the MCAI") to correct an unsafe
condition for certain Mitsubishi Heavy Industries, Ltd. Model MU-2B,
MU-2B-15, MU-2B-20, MU-2B-25, MU-2B-26, MU-2B-30, MU-2B-35, and MU-2B-
36 airplanes. The MCAI requires replacing the PPC lever bolt with the
This proposed AD would require this bolt replacement and would also
require installing a secondary retention feature and repetitive
inspections of the PPC lever to prevent future reoccurrence.
Also since AD 75-16-20 was issued, Mitsubishi has type certificated
Models MU-2B-26A, MU-2B-36A, MU-2B-40, and MU-2B-60 airplanes. These
models have the same PPC configuration and are subject to the same
unsafe condition. As a result, the proposed AD would add these models
to the applicability. You may examine the MCAI in the AD docket on the
internet at https://www.regulations.gov by searching for and locating
Docket No. FAA-2020-0781.
Related Service Information Under 1 CFR Part 51
Mitsubishi has issued MU-2 Service Recommendation No. 049/76-002,
dated June 29, 2018, and MU-2 Service Recommendation No. 080, dated
June 29, 2018. This service information contains procedures for
installing a PPC lever secondary retention feature to secure the PPC
lever. These documents are distinct since they apply to different
airplane models and configurations.
Mitsubishi has also issued MU-2 Service Bulletin No. 106/76-004,
dated February 24, 2016, and MU-2 Service Bulletin No. 244, dated
December 25, 2015. This service information contains procedures for
replacing the PPC lever clamping bolt. These documents are distinct
since they apply to different airplane models and configurations.
Honeywell International Inc. has issued Service Bulletin TPE331-72-
2190, Revision 0, dated December 21, 2011. The procedures in this
service information include instructions for incorporating a threaded
hole in the splined end of the shouldered shaft of the PPC assembly and
re-identifying the shouldered shaft part number. The threaded hole is
used to accommodate a secondary retention method to secure the PPC
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.
This product has been approved by the aviation authority of another
country, and is approved for operation in the United States. Pursuant
to our bilateral agreement with the State of Design Authority, the FAA
has been notified of the unsafe condition described in the MCAI and
service information referenced above. The FAA is proposing this AD
because the FAA evaluated all the relevant information and determined
the unsafe condition described previously is likely to exist or develop
on other products of the same type design.
Proposed AD Requirements
This proposed AD would retain the repetitive inspection
requirements of AD 75-16-20 and would also require installing a
secondary retention feature and reporting certain inspection results to
the FAA. In addition, this proposed AD would add models to the
applicability that were not type certificated when AD 75-16-20 was
Differences Between This Proposed AD and the MCAI
This proposed AD would require an installation of a secondary
retention feature in the threaded end of the PPC input shaft,
repetitive inspections of the security of the PPC lever, and reporting
certain inspection results to the FAA. The MCAI does not include these
The applicability of the MCAI is limited to certain Mitsubishi
airplane models and serial numbers. However, this proposed AD would
apply to all Mitsubishi Models MU-2B, MU-2B-10, MU-2B-15, MU-2B-20, MU-
2B-25, MU-2B-26, MU-2B-26A, MU-2B-30, MU-2B-35, MU-2B-36, MU-2B-36A,
MU-2B-40, and MU-2B-60 airplanes because the type design allows
installation of the affected PCC lever linkage on other models.
Costs of Compliance
The FAA estimates that this proposed AD affects 260 airplanes of
The FAA estimates the following costs to comply with this proposed
AD. The average labor rate is $85 per work hour.
||2 work-hours x $85 per hour =
||1 work-hour x $85 per hour =
$85 per inspection cycle
||$85 per inspection cycle
||$22,100 per inspection cycle
The FAA estimates the following costs
to do any necessary on-
condition actions for the incorporation of the threaded hole and
reporting requirement. The FAA has no way of determining the number of
aircraft that might need these on-condition actions:
|Incorporation of threaded hole
||4 work-hours x $85 per hour =
||1 work-hour x $85 per hour
If the PPC lever detaches, the necessary
corrective actions could
vary significantly from airplane to airplane. The FAA has received no
definitive data that would enable estimating the cost to install the
PPC lever on each airplane or the number of airplanes that may require
Paperwork Reduction Act
A federal agency may not conduct or sponsor, and a person is not
required to respond to, nor shall a person be subject to penalty for
failure to comply with a collection of information subject to the
requirements of the Paperwork Reduction Act unless that collection of
information displays a current valid OMB control number. The OMB
Control Number for this information collection is 2120-0056. Public
reporting for this collection of information is estimated to be
approximately 1 hour per response, including the time for reviewing
instructions, searching existing data sources, gathering and
maintaining the data needed, completing and reviewing the collection of
information. All responses to this collection of information are
mandatory as required by this AD; the nature and extent of
confidentiality to be provided, if any. Send comments regarding this
burden estimate or any other aspect of this collection of information,
including suggestions for reducing this burden to: Information
Collection Clearance Officer, Federal Aviation Administration, 10101
Hillwood Parkway, Fort Worth, TX 76177-1524.
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.
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
(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
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.
Sec. 39.13 [Amended]
2. The FAA amends Sec. 39.13 by:
a. Removing Airworthiness Directive (AD) 75-16-20, Amendment 39-2294
(40 FR 31751, July 29, 1975); and
b. Adding the following new AD: