Airworthiness Directives; Superior Air Parts, Inc. Engines and Lycoming Engines Reciprocating Engines With a Certain SAP Crankshaft Assembly, 79828-79833 [2020-27149]
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79828
Federal Register / Vol. 85, No. 239 / Friday, December 11, 2020 / Rules and Regulations
Commission for Aeronautics, Inc.
(RTCA) Document DO–178C, Software
Considerations in Airborne Systems and
Equipment Certification, provides
software design assurance levels most
commonly used for the major,
hazardous/severe-major, and
catastrophic failure condition
categories. The AP/SAS equipment
must be qualified for the expected
installation environment. The test
procedures prescribed in RTCA
Document DO–160G, Environmental
Conditions and Test Procedures for
Airborne Equipment, are recognized by
the FAA as acceptable methodologies
for finding compliance with the
environmental requirements. Equivalent
environment test standards may also be
acceptable.
The environmental qualification
provides data to show that the AP/SAS
can perform its intended function under
the expected operating condition. Some
considerations for environmental
concerns are installation locations and
the resulting exposure to environmental
conditions for the AP/SAS equipment,
including considerations for other
equipment that may be environmentally
affected by the AP/SAS equipment
installation. The level of environmental
qualification must be related to the
severity of the considered failure
conditions and effects on the rotorcraft.
These 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.
Applicability
As discussed above, these special
conditions are applicable to the BTCL
Model 505 helicopter. Should Garmin
apply at a later date for a STC to modify
any other model included on Type
Certificate Number R00008RD to
incorporate the same novel or unusual
design feature, these special conditions
would apply to that model as well.
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Conclusion
This action affects only a certain
novel or unusual design feature on the
BTCL Model 505 helicopter. It is not a
rule of general applicability and affects
only the applicant who applied to the
FAA for approval of this feature on the
helicopter.
Authority: 49 U.S.C. 106(f), 106(g), 40113,
44701, 44702, 44704.
Accordingly, pursuant to the
authority delegated to me by the
Administrator, the following special
conditions are issued as part of the
supplemental type certification basis for
Bell Textron Canada Limited (BTCL)
Model 505 helicopters, as modified by
Garmin International, Inc.
Instead of the requirements of 14 CFR
§ 27.1309(b) and (c), the following must
be met for certification of the autopilot
and stability augmentation system
installed on BTCL Model 505
helicopters:
(a) The equipment and systems must
be designed and installed so that any
equipment and systems do not
adversely affect the safety of the
rotorcraft or its occupants.
(b) The rotorcraft systems and
associated components considered
separately and in relation to other
systems must be designed and installed
so that:
(1) The occurrence of any catastrophic
failure condition is extremely
improbable;
(2) The occurrence of any hazardous
failure condition is extremely remote;
and
(3) The occurrence of any major
failure condition is remote.
(c) Information concerning an unsafe
system operating condition must be
provided in a timely manner to the crew
to enable them to take appropriate
corrective action. An appropriate alert
must be provided if immediate pilot
awareness and immediate or subsequent
corrective action is required. Systems
and controls, including indications and
annunciations, must be designed to
minimize crew errors that could create
additional hazards.
Issued in Fort Worth, Texas on November
19, 2020.
Jorge Castillo,
Manager, Rotorcraft Standards Branch, Policy
and Innovation Division, Aircraft
Certification Service.
[FR Doc. 2020–26047 Filed 12–9–20; 4:15 pm]
BILLING CODE 4910–13–P
Authority Citation
The authority citation for these
special conditions is as follows:
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Federal Aviation Administration
The Special Conditions
List of Subjects in 14 CFR Part 27
Aircraft, Aviation safety, Reporting
and recordkeeping requirements.
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. FAA–2018–1077; Project
Identifier 2018–NE–40–AD; Amendment 39–
21354; AD 2020–25–12]
RIN 2120–AA64
Airworthiness Directives; Superior Air
Parts, Inc. Engines and Lycoming
Engines Reciprocating Engines With a
Certain SAP Crankshaft Assembly
Federal Aviation
Administration (FAA), DOT.
ACTION: Final rule.
AGENCY:
The FAA is adopting a new
airworthiness directive (AD) for all
Superior Air Parts, Inc. (SAP) Model
IO–360-series and O–360-series
reciprocating engines and certain
Lycoming Engines (Lycoming) Model
AEIO–360-, IO–360-, and O–360-series
reciprocating engines with a certain
SAP crankshaft assembly installed. This
SAP crankshaft assembly is installed as
original equipment on the affected SAP
engines and as a replacement part under
parts manufacturer approval (PMA) on
the affected Lycoming engines. This AD
was prompted by three crankshaft
assembly failures that resulted in the
loss of engine power and immediate or
emergency landings. This AD requires
the removal from service of all affected
crankshaft assemblies. The FAA is
issuing this AD to address the unsafe
condition on these products.
DATES: This AD is effective January 15,
2021.
SUMMARY:
Examining the AD Docket
You may examine the AD docket at
https://www.regulations.gov by
searching for and locating Docket No.
FAA–2018–1077; 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, any comments received, and
other information. The address for
Docket Operations is 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:
Justin Carter, Aviation Safety Engineer,
Fort Worth ACO Branch, FAA, 10101
Hillwood Parkway, Fort Worth, TX
76177; phone: (817) 222–5146; fax: (817)
222–5245; email: justin.carter@faa.gov.
SUPPLEMENTARY INFORMATION:
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Background
The FAA issued a notice of proposed
rulemaking (NPRM) to amend 14 CFR
part 39 by adding an AD that would
apply to all SAP Model IO–360-series
and O–360-series reciprocating engines
and certain Lycoming Model AEIO–360, IO–360-, and O–360-series
reciprocating engines with a certain
SAP crankshaft assembly installed. The
NPRM published in the Federal
Register on January 29, 2020 (85 FR
5173). The NPRM was prompted by
three crankshaft assembly failures that
resulted in the loss of engine power and
immediate or emergency landings. The
FAA determined that the crankshaft
assembly failures resulted from the
manufacturing process at SAP’s
crankshaft vendor during 2012 and 2014
causing excessive residual white layer
of iron nitride forming on the
assemblies. This white layer is brittle
and can lead to spalling or fatigue
cracking of the crankshaft assembly as a
result of the normal mechanical loads
during engine operation. The FAA’s
analysis concluded that all three SAP
crankshaft assembly failures were the
result of this fatigue cracking. In the
NPRM, the FAA proposed to require the
removal from service of all affected
crankshaft assemblies. The unsafe
condition, if not addressed, could result
in failure of the engine, in-flight
shutdown, and loss of the airplane.
Discussion of Final Airworthiness
Directive Comments
The FAA received comments from
seven commenters. The commenters
were SAP, the Aircraft Owners and
Pilots Association (AOPA), and five
individual commenters. Three
commenters requested that the FAA
extend the comment period. One
commenter requested the withdrawal of
the AD. Two commenters asked the
FAA to release more information. One
commenter asked for the status of the
AD and if the crankshaft assembly is
safe to fly. The following presents the
comments received on the NPRM and
the FAA’s response to each comment.
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Request To Withdraw the NPRM: White
Layer Does Not Contribute to Fracture
SAP stated that data from an
independent laboratory test does not
support the statement in the NPRM that
the crankshaft failures were a result of
residual white layer formation, also
known as a compound layer, on certain
crankshaft assemblies as a result of
improper manufacturing by a thirdparty vendor. SAP stated that the
fractured crankshafts were all within
specifications. SAP found both the
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material and the heat treatment to be
within all engineering requirements and
consistent with other crankshafts in
general aviation piston aircraft engines.
SAP noted that these requirements were
consistent with the engineering testing
conducted by SAP in pursuit of FAA
PMA certification. Additionally, SAP
stated the fractures were not consistent
with fatigue fractures due to excessive
white layer, and that no manufacturing
or material defect was found in
independent metallurgical laboratory
analysis. The FAA infers from this
comment that SAP is requesting that the
FAA withdraw the NPRM.
The FAA disagrees with SAP’s
analysis. BakerRisk Project No. 01–
05929–003–17, dated August 15, 2017,
for SAP crankshaft assembly S/N SP14–
0202, which failed on March 6, 2017,
found that there was a continuous white
layer at the surface of the radius,
extending up to the location of the
fracture, and that the white layer may
have contributed to early crack
initiation. 1 The continuous white layer
at the origin was 0.0007 inch. BakerRisk
Project No. 01–05929–006–17, Rev. 1,
dated May 8, 2018, for SAP crankshaft
assembly S/N SP14–0194, which failed
on August 3, 2017, found that the
continuous white layer at the surface of
the forward journal radius, extending up
to the location of the fracture, was
0.0006 inch. According to the report,
this indicates that the process being
used to remove the white layer was not
removing the entire white layer.
Because it found that the presence of the
white layer can lower fatigue resistance
and result in premature fatigue crack
initiation, the report included
recommendations to review the material
and the processes that define the
crankshaft journals, especially the
nitride case hardening and white layer
removal process. 2
SAP’s comment cited Hurst
Metallurgical Research Laboratory, Inc.,
(Hurst) Report No. 73900, dated
February 22, 2019, for SAP crankshaft
assembly S/N SP13–0150, which failed
on October 31, 2018. This Hurst report
found that the continuous white layer of
iron nitride at the surface of the forward
journal radius was 0.0001 inch. The
FAA, however, disagrees with the
reported thickness of the white layer.
The report includes two scaled
photographs (photographs No. 11 and
12), magnified 100 times and 500 times,
respectively. Using the scaling bar
provided in the photographs, the FAA
1 See pp. 2–3 of BakerRisk Project No. 01–05929–
003–17.
2 See pp. 4–5 of BakerRisk Project No. 01–05929–
006–17, Rev. 1.
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determined that the white layer is
0.0009 inch. Although SAP stated a
white layer of up to 0.001 inch is
allowed, SAP based this figure on an
SAE Aerospace Material specification
and not on the original equipment
manufacturer’s (OEM) specifications. A
white layer of 0.0009 inch exceeds the
amount allowed by the OEM.
As supported by the reports, the FAA
finds that white layer contributed to the
early crack initiation and, on all failed
crankshaft assemblies, exceeded OEM
specifications. Based on the foregoing,
the FAA finds no basis to withdraw the
NPRM.
Request To Withdraw the NPRM: White
Layer Does Not Increase Fatigue
Resistance
SAP stated that the presence of a
white layer does not reduce the fatigue
resistance of material at the surface, but
rather increases the fatigue resistance of
that same material. SAP cited a study by
Major, Jakl, and Huba´lovsky´ for the
observation that the application of
plasma carburizing can lead to about a
25% increase in fatigue resistance.3 SAP
stated a study by Hiraoka and Ishida 4
shows a marked increase in fatigue limit
in a specimen with a 10 mm thick white
layer as opposed to a specimen without
a white layer, with a slight increase in
the fatigue limit in a specimen with a 20
mm thick white layer as compared to the
specimen with a 10 mm thick white
layer. The FAA infers from this
comment that SAP is requesting that the
FAA withdraw the NPRM.
The FAA disagrees with the
applicability of these studies to the
unsafe condition identified in this AD.
Although the application of plasma
carburizing can lead to an increase in
the fatigue resistance, the affected
crankshaft assemblies were not plasma
carburized. Therefore, the Major, Jakl,
and Huba´lovsky´ study is not relevant
here. Although the Hiraoka and Ishida
study did reveal an increase in fatigue
limit of gas nitrided steel with a white
layer over one without a white layer, the
study’s test environment did not
replicate the conditions applicable to an
engine crankshaft as identified in
Advisory Circular No. 33.19–1,
‘‘Guidance Material for 14 CFR § 33.19,
Durability, for Reciprocating Engine
Redesigned Parts,’’ dated September 27,
ˇ tepa´n Major, Vladimir Jakl, & Sˇtepa´n
3S
Huba´lovsky´, Effect of carburizing on fatigue life of
high-strength steel specimen under push-pull
loading, Advances in Engineering Mechanics and
Materials, 143 (2014).
4 Yaushi Hiraoka & Akihiro Ishida, Effect of
Compound Layer Thickness Composed of g’-Fe4N
on Rotated-Bending Fatigue Strength in GasNitrided JIS–SCM435 Steel, 58 MATERIALS
TRANSACTIONS 993 (2017).
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2004 (AC 33.19–1). A crankshaft is a
part whose primary fatigue mechanism
is a forced vibratory response in
combination with a resonant vibratory
response that occurs at any engine
speed at which the natural frequency of
the part (or assembly that includes the
part) coincides with the frequency of a
combustion or inertia harmonic. AC
33.19–1 recommends 300 hours of
engine tests, including a vibration test at
peak torsional resonance conditions, to
test the fatigue strength of the
crankshaft.
The white layer is well-established to
be problematic in that it is brittle. The
OEM removes the white layer during the
manufacturing process. As a PMA
holder, 14 CFR 21.303 requires that SAP
produce a part that is equivalent to the
OEM part. Based on the foregoing, the
FAA finds no basis to withdraw the
NPRM.
Request To Withdraw the NPRM:
Operation Outside of Normal
Conditions
SAP stated the fractures of the
crankshaft assemblies cited in the
NPRM were due to misuse, abuse, or
lack of lubrication. In support, SAP
cited Hurst Report No. 73614, Rev. 1,
dated December 7, 2018, for SAP
crankshaft assembly S/N SP14–0202
and Hurst Report No. 73617, Rev. 1,
dated December 7, 2018, for SAP
crankshaft assembly S/N SP14–0194,
which indicate that the fractures were
likely initiated by abnormal service
conditions, such as a propeller strike
and a start-up of the engine in a lowtemperature (below optimal performing
temperature) environment. SAP also
cited Hurst Report No. 73900 for SAP
crankshaft assembly S/N SP13–0150,
which indicates that likely contributors
of the failure include rod sliding bearing
failure due to insufficient lubrication,
misalignment of the crankshaft, and
improper engine performance from
inadequate operation procedure
resulting in high bending moment at the
radius locations from excessive force
from the piston assembly. SAP stated
that all three of these crankshafts were
operated in a flight school environment.
The FAA infers from this comment that
SAP is requesting that the FAA
withdraw the NPRM.
The FAA disagrees that the fracture
was initiated by the operation of the
engines outside of ‘‘normal’’ conditions
or parameters. With respect to Hurst
Report No. 73614 for SAP crankshaft
assembly S/N SP14–0202 and Hurst
Report No. 73617 for SAP crankshaft
assembly S/N SP14–0194, none of the
engines exhibited evidence of propeller
strikes, and none were started below
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optimal performance temperature.
According to Lycoming,5 cold weather
requiring the use of pre-heat to avoid a
cold engine start-up is 10 degrees
Fahrenheit or below. Two of the
incidents occurred in August (Canada)
and October (Florida), making cold
engine start-up unlikely. The third
incident occurred in March
(Massachusetts), which had a low of 16
degrees Fahrenheit at 6 a.m. and
proceeded to a high of 41 degrees
Fahrenheit in the afternoon.
With respect to Hurst Report No.
73900 for SAP crankshaft assembly S/N
SP13–0150, the pilot and mechanic
separately reported the engine had good
oil pressure, indicating that the engine
did not suffer from a lack of proper
lubrication at the time of the crankshaft
assembly failure. The report identifies
possible contributors of single origin
fatigue failure, including the
misalignment of the crankshaft
assembly or improper engine
performance from inadequate operation
procedure resulting in high bending
moment at the radius locations from
excessive force from the piston
assembly. However, the report does not
provide evidence to support these
contributors. Based on the foregoing, the
FAA declines to withdraw the NPRM.
Request To Review National
Transportation Safety Board (NTSB)
Reports
An individual commenter requested
to review the NTSB reports on the
accidents mentioned in the NPRM. The
commenter was unable to locate
anything in the NTSB database
concerning engine stoppage in aircraft
powered by Lycoming or SAP O–360 or
IO–360 engines.
The NTSB did not generate reports for
the three incidents that resulted from
the crankshaft failures discussed in the
NPRM. Therefore, the FAA did not rely
on NTSB reports and is not in
possession of any report generated as a
result of the three incidents.
Request To Add Metallurgical Analyses
to the Docket
An individual commenter requested
that the FAA add its metallurgical
analyses to the docket. The commenter
stated that it was his understanding
from discussions with the FAA that the
FAA has shared its metallurgical
analyses with SAP.
The FAA agrees and has uploaded the
BakerRisk and Hurst metallurgical
5 Lycoming Service Instruction No. 1505, dated
July 1, 2002: ‘‘The use of pre-heat will facilitate
starting during cold weather, and is required when
the engine has been allowed to drop to
temperatures below +10 °F/¥12 °C.’’
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reports provided by SAP to the AD
docket, as SAP has agreed to release
these reports to the public. The FAA,
however, did not perform its own
metallurgical testing. The FAA instead
relied on metallurgical testing
performed by BakerRisk and Hurst for
SAP.
Request To Release Pertinent
Information
An individual commenter requested
that the FAA release information it has
on this issue, including the
circumstances of the crankshaft
assembly failures, the cost of crankshaft
assembly replacement, and the scope of
the proposed action.
The FAA agrees to provide additional
information about the circumstances of
the failures. In each incident, the
crankshaft assembly broke into two
pieces. The March 6, 2017, incident
resulted in the crankshaft separating at
journal #2 while the August 3, 2017,
and October 31, 2018, incidents both
resulted in a separation of the
crankshaft at journal #4. All of the
incidents involved flight-training
aircraft. Additionally, as discussed
previously, the FAA has uploaded the
metallurgical reports to the AD docket.
Both the NPRM and this final rule
adequately explain the scope of the AD
and contain a detailed estimate of the
costs of compliance within this AD,
including the cost of the crankshaft
assembly replacement, labor cost, and
total estimated cost to U.S. operators.
This final rule also discusses the net
benefit of this AD.
Request To Consider Costs of
Implementing This AD
An individual commenter requested
that the FAA consider the financial
costs and unintended consequences of
this AD, such as decreased aircraft
value. The commenter estimates that the
value of his aircraft has been reduced by
at least $15,000 since the publication of
the NPRM.
The FAA disagrees. The cost analysis
in AD rulemaking actions typically
includes only the costs associated with
complying with the AD and does not
include indirect costs such as loss of
aircraft value. The FAA acknowledges
that the general obligation of the
operator to maintain its aircraft in an
airworthy condition is sometimes
expensive. However, and as discussed
in more detail in the Benefits section,
the FAA estimates that the benefits of
this AD greatly exceed its cost.
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Request To Clarify Applicability
An individual commenter asked if
SAP crankshaft assemblies earlier than
2012 are affected by this AD.
The first affected SAP crankshaft
assembly was shipped on July 31, 2012.
SAP crankshaft assemblies assembled
before July 31, 2012, are not affected by
this AD.
Request To Extend Comment Period
SAP and AOPA requested that the
FAA extend the comment period by 60
days to enable SAP to gather more
information. SAP asked for more time to
research, gather, and respond
appropriately to the NPRM. AOPA
similarly requested an extension to
review the costs and overall scope, and
to gather information to respond to the
NPRM. SAP, AOPA, and an individual
commenter requested the FAA extend
the comment period because of delays
due to the COVID–19 pandemic, such as
the closure of laboratories for further
testing and the reduction in aircraft
operations.
The FAA disagrees. At SAP’s request,
the FAA met with SAP and AOPA in
April 2020 to discuss the NPRM. During
that meeting, the participants discussed
certain aspects of the NPRM, including
the white layer and metallurgical
reports, the three failed crankshaft
assemblies, and SAP’s request for a 60day extension to the comment period. A
summary of the meeting is available in
the AD docket. None of the information
provided by SAP or AOPA justifies an
extension of the comment period. If
investigations by SAP or others reveal
information that changes the FAA’s
determination regarding the unsafe
condition, the FAA will consider future
rulemaking.
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Request for a Status Update
An individual commenter requested
information regarding the FAA’s
progress on issuing this AD. The
commenter stated that based on
feedback from SAP, the crankshaft
assembly is safe and that a metallurgy
company inspected one of the affected
crankshaft assemblies and did not find
any issues.
The FAA disagrees with the
assessment from SAP. The FAA
reviewed the metallurgical reports from
the incidents of failed crankshaft
assemblies and determined that an
unsafe condition exists in other
crankshaft assemblies of the same type
design. In each incident, the crankshaft
assembly broke into two pieces, leading
to loss of engine power. The crankshaft
assemblies involved in the three
incidents were found to have excessive
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white layer. As a result, this AD requires
removing all affected crankshaft
assemblies from service within 25
engine operating hours after the
effective date of this AD.
Conclusion
The FAA reviewed the relevant data,
considered the comments received, and
determined that air safety requires
adopting the AD as proposed.
Accordingly, the FAA is issuing this AD
to address the unsafe condition on these
products.
Regulatory Flexibility Determination
The Regulatory Flexibility Act of 1980
(Pub. L. 96–354, codified as amended at
5 U.S.C. 601–612) (RFA) establishes ‘‘as
a principle of regulatory issuance that
agencies shall endeavor, consistent with
the objectives of the rule and of
applicable statutes, to fit regulatory and
informational requirements to the scale
of the businesses, organizations, and
governmental jurisdictions subject to
regulation. To achieve this principle,
agencies are required to solicit and
consider flexible regulatory proposals
and to explain the rationale for their
actions to assure that such proposals are
given serious consideration.’’ Public
Law 96–354, 2(b), September 19, 1980.
The RFA covers a wide-range of small
entities, including small businesses,
not-for-profit organizations, and small
governmental jurisdictions. Agencies
must perform a review to determine
whether a rule will have a significant
economic impact on a substantial
number of small entities. If the agency
determines that it will, the agency must
prepare a regulatory flexibility analysis
as described in the RFA.
The FAA published an Initial
Regulatory Flexibility Analysis (IRFA)
in the proposed rule to aid the public in
commenting on the potential impacts to
small entities. The FAA considered the
public comments in developing the final
rule and this Final Regulatory
Flexibility Analysis (FRFA).
Benefits
The FAA found that SAP, the
manufacturer of the crankshaft
assemblies, sold 192 SAP crankshaft
assemblies to date: 115 of these
crankshaft assemblies are estimated to
be installed on type certificated
airplanes and the remaining 77
crankshaft assemblies are estimated to
be installed on experimental aircraft.
The FAA’s risk analysis indicates that
100 percent of crankshaft assembly
failures will destroy the engine. Using
the historical incident data (2000–2014),
the FAA assumes that 24.4 percent of
crankshaft assembly failures will result
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79831
in aircraft hull loss while 22 percent of
crankshaft assembly failures will result
in fatalities. There would be an average
of 2.1 fatalities per each crankshaft
assembly accident. Applying these
probabilities to the estimated 115
crankshaft assemblies installed on type
certificated airplanes, the FAA estimates
that if these crankshaft assemblies are
not replaced and continue to be used in
these airplanes, this will result in 53
fatalities (2.1 fatalities per crankshaft
accident × 22 percent probability of a
crankshaft assembly failure resulting in
fatalities × 115 crankshaft assemblies)
and 28 aircraft losses (24.4 percent
probability of a crankshaft assembly
failure destroying the airplane). This AD
will prevent all 53 fatalities and 28
aircraft losses.
Using an average price of $50,000 for
a small single engine airplane, an
average price of $30,000 for a 360-series
engine and the Department of
Transportation’s $9.6 million estimate
for the Value of Statistical Life (VSL)
from the ‘‘Revised Departmental
Guidance on Valuation of a Statistical
Life in Economic Analysis,’’ 6 the FAA
estimated this AD final rule will result
in monetized benefits of $512.8
million. 7
Costs of Compliance
The costs of compliance with this AD
consist of the cost to remove and replace
a crankshaft assembly. The FAA
estimates that this AD will affect 115
crankshaft assemblies installed on
airplanes of U.S. registry. This cost
estimate does not include 77 SAP
crankshaft assemblies installed on
experimental engines since this AD does
not apply to these engines. The
estimated compliance cost per
crankshaft assembly is identified below.
Labor cost = 61 hours per crankshaft
assembly replacement × $85 Hourly
Wage = $5,185.
Equipment costs per crankshaft
assembly replacement = $9,636 (Source:
Average of the two vendors).
$5,185 labor per crankshaft assembly
+ $9,636 equipment costs per crankshaft
6 https://www.transportation.gov/office-policy/
transportation-policy/revised-departmentalguidance-on-valuation-of-a-statistical-life-ineconomic-analysis.
7 53 preventable fatalities will amount to $508.8
million in benefits of this rule. (53 × $9.6 million).
The value of 28 airplane losses is $1.4 million (28
× $50,000). The remaining 75.6 percent of
crankshaft failures (100 percent¥24.4 percent
crankshaft failure destroying the airplane) will
result in $2.6 million in engine damages. (115 ×
0.756 probability of crankshaft failure damaging an
airplane engine × $30,000 value of 360 engine).
Therefore, the total estimated benefits are $512.8
million ($508.8 million preventable fatalities + $1.4
million avoidable airplane loss + $2.6 million
preventable engine damages).
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Federal Register / Vol. 85, No. 239 / Friday, December 11, 2020 / Rules and Regulations
assembly replacement = $14,821
compliance cost per engine.
The total costs to U.S. operators is
$1,704,415 ($14,821 × 115), or $119,309
in annualized costs in perpetuity using
a 7 percent discount rate. There are no
additional costs after removing and
replacing the crankshaft assembly.
Therefore, the FAA estimates that the
net benefit of this final rule will be
$511.1 million ($512.8 million benefits
¥$1.7 million costs), or $35.77 million
in annualized net benefits using a 7
percent discount rate in perpetuity.
jbell on DSKJLSW7X2PROD with RULES
Final Regulatory Flexibility Analysis
Under § 604(a) of the RFA, the final
analysis must contain the following:
(1) A statement of the need for, and
objectives of, the rule;
(2) A statement of the significant
issues raised by the public comments in
response to the IRFA, a statement of the
assessment of the agency of such issues,
and a statement of any changes made in
the proposed rule as a result of such
comments;
(3) The response of the agency to any
comments filed by the Chief Counsel for
Advocacy of the Small Business
Administration (SBA) in response to the
proposed rule, and a detailed statement
of any change made to the proposed rule
in the final rule as a result of the
comments;
(4) A description of and an estimate
of the number of small entities to which
the rule will apply or an explanation of
why no such estimate is available;
(5) A description of the projected
reporting, record-keeping, and other
compliance requirements of the
proposed rule, including an estimate of
the classes of small entities which will
be subject to the requirement and the
type of professional skills necessary for
the preparation of the report or record;
(6) A description of the steps the
agency has taken to minimize the
significant economic impact on small
entities consistent with the stated
objectives of applicable statutes,
including a statement of the factual,
policy, and legal reasons for selecting
the alternative adopted in the final rule
and why each of the other significant
alternatives to the rule considered by
the agency which affect the impact on
small entities was rejected.
1. Need for and Objectives of the Rule
This final rule AD was prompted by
three crankshaft assembly failures that
resulted in the loss of engine power and
immediate or emergency landings. The
FAA is issuing this AD to prevent
failure of the crankshaft assembly by
requiring the removal of all affected
crankshaft assemblies from service.
VerDate Sep<11>2014
22:08 Dec 10, 2020
Jkt 253001
Failure of a crankshaft assembly, if not
addressed, could result in failure of the
engine, in-flight shutdown, and loss of
the airplane.
2. Significant Issues Raised in Public
Comments
An individual commenter noted that
some owners of affected aircraft may not
be in a position to absorb the $15,000
cost of the crankshaft assembly
replacement. The commenter proposed
that the financial costs of this AD would
exceed the FAA estimates in some cases
and, therefore, the unintended
consequences of this AD would destroy
value out of proportion to the
preservation of the safety of the national
airspace system and the general public.
The FAA estimates the cost of
replacing a single crankshaft assembly
at $14,821. The risk of not replacing the
crankshaft is not insignificant, and the
crankshaft failure could cause engine
loss, airplane loss, or fatality valued at
$30,000, $50,000, and $9.6 million,
respectively. When these potentially
substantial losses and risks of fatality to
each airplane owner and operator are
considered, the $14,821 compliance cost
per airplane is minimal. Further, the
FAA estimates the benefits of this AD to
be $512.8 million, which greatly
exceeds its cost of $1.7 million,
justifying this final rule.
Based on the risk and benefits
analysis above, the FAA determined
that no changes are necessary to the
final rule as a result of this individual
comment.
3. Response to SBA Comments
The Chief Counsel for Advocacy of
the SBA did not file any comments in
response to the proposed rule.
4. Small Entities to Which the Rule Will
Apply
This AD applies to all SAP Model IO–
360-series and O–360-series
reciprocating engines and certain
Lycoming Model AEIO–360-, IO–360-,
and O–360-series reciprocating engines
with a certain SAP crankshaft assembly
installed. This SAP crankshaft assembly
is installed as original equipment on the
affected SAP engines and as a
replacement part under PMA on the
affected Lycoming engines. These
engines are installed on airplanes
performing various activities including,
but not limited to, flight training,
charter flights, and agriculture.
Under the RFA, the FAA must
determine whether a final rule
significantly affects a substantial
number of small entities. The FAA uses
the SBA criteria for determining
whether an affected entity is small. For
PO 00000
Frm 00054
Fmt 4700
Sfmt 4700
aircraft and engine manufacturers,
aviation operators, and any business
using an aircraft, the SBA criterion is
1,500 or fewer employees. The FAA
estimates that this AD affects 115
crankshaft assemblies installed on
airplanes of U.S. registry. The FAA does
not have any information or data on
whether these entities are small
businesses according to the definition
established by the SBA. Although in the
NPRM the FAA requested comments
and data that would allow the agency to
more accurately assess the number of
employees and sales revenues of the
affected entities, no such comments or
data was received. Accordingly, the
FAA assumes for purposes of this final
rule that some of the affected entities are
small businesses.8 The FAA determines
that the estimated $14,821 compliance
cost per aircraft due to this rule will
have a significant impact on a
substantial number of small entities.
5. Projected Reporting, Record-Keeping,
and Other Compliance Requirements
There are no record-keeping costs or
other compliance costs associated with
this final rule.
6. Significant Alternatives Considered
As part of the FRFA, the FAA is
required to consider regulatory
alternatives that may be less
burdensome. The FAA considered the
following alternatives:
Do nothing: This option is not
acceptable because the risk of additional
failures of these crankshaft assemblies
constitutes a known unsafe condition.
The FAA estimates that this AD will
prevent 53 fatalities and 28 aircraft
losses, and monetized benefits of $512.8
million.
Periodic inspections: This option is
not possible as the crankshaft assembly
cannot be inspected without destroying
it.
There is no direct safety alternative to
the replacement of the crankshaft
assembly. The replacement addresses a
safety issue aimed at preventing the
failure of the crankshaft assembly.
Therefore, the FAA rejected these two
regulatory alternatives and determined
that this rulemaking may have a
significant economic impact on a
substantial number of small entities.
8 The FAA recognizes that many of these affected
airplanes are recreational. The 2016 GAMA
Databook shows that of 141,141 active General
Aviation piston aircraft, 104,669 are used for
personal or recreational purposes (74 percent),
Using this distribution, only 30 of the 115
crankshaft assemblies would be installed in
airplanes operated for business use.
E:\FR\FM\11DER1.SGM
11DER1
Federal Register / Vol. 85, No. 239 / Friday, December 11, 2020 / Rules and Regulations
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
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 above, I
certify that this AD:
(1) Is not a ‘‘significant regulatory
action’’ under Executive Order 12866,
and
(2) Will not affect intrastate aviation
in Alaska.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation
safety, Incorporation by reference,
Safety.
The Amendment
Accordingly, under the authority
delegated to me by the Administrator,
the FAA amends 14 CFR part 39 as
follows:
1. The authority citation for part 39
continues to read as follows:
■
Authority: 49 U.S.C. 106(g), 40113, 44701.
[Amended]
2. The FAA amends § 39.13 by adding
the following new airworthiness
directive:
jbell on DSKJLSW7X2PROD with RULES
■
2020–25–12 Superior Air Parts, Inc.:
Amendment 39–21354; Docket No.
FAA–2018–1077; Project Identifier
2018–NE–40–AD.
VerDate Sep<11>2014
22:08 Dec 10, 2020
Jkt 253001
This airworthiness directive (AD) is
effective January 15, 2021.
(b) Affected ADs
None.
(c) Applicability
This AD applies to the reciprocating engine
models identified in paragraphs (c)(1) and (2)
of this AD with a Superior Air Parts, Inc.
(SAP) crankshaft assembly, part number (P/
N) SL36500–A20 or P/N SL36500–A31, with
serial numbers 82976–01; 82976–02; SP12–
0003 through SP12–0089, inclusive; SP13–
0034 through SP13–0150, inclusive; or SP14–
0151 through SP14–0202, inclusive;
installed.
(1) With SAP crankshaft assembly, P/N
SL36500–A20, installed:
(i) SAP Model IO–360-series and O–360series reciprocating engines.
(ii) Lycoming Engines (Lycoming) Model
IO–360–B2F, IO–360–L2A, O–360, O–360–
A2A, O–360–A2D, O–360–A2E, O–360–A2F,
O–360–A2G, O–360–B2A, O–360–C2A, O–
360–C2C, O–360–C2D, O–360–C2E, O–360–
D2A, and O–360–D2B reciprocating engines.
(2) With SAP crankshaft assembly, P/N
SL36500–A31, installed:
(i) SAP Model IO–360-series and O–360series reciprocating engines.
(ii) Lycoming Model AEIO–360–H1A, IO–
360–B1A, IO–360–B1B, IO–360–B1D, IO–
360–B1E, IO–360–B1F, IO–360–M1A, O–360,
O–360–A1A, O–360–A1C, O–360–A1D, O–
360–A2A, O–360–C1A, O–360–C1G, O–360–
C1C, O–360–C1E, and O–360–C1F
reciprocating engines.
Note 1 to paragraph (c): This SAP
crankshaft assembly may be installed as a
replacement part under parts manufacturer
approval on the affected Lycoming engines.
(d) Subject
Joint Aircraft System Component (JASC)
Code 8520, Reciprocating Engine Power
Section.
(e) Unsafe Condition
This AD was prompted by three crankshaft
assembly failures that resulted in the loss of
engine power and immediate or emergency
landings. The FAA is issuing this AD to
prevent failure of the crankshaft assembly.
The unsafe condition, if not addressed, could
result in failure of the engine, in-flight
shutdown, and loss of the airplane.
(f) Compliance
Comply with this AD within the
compliance times specified, unless already
done.
PART 39—AIRWORTHINESS
DIRECTIVES
§ 39.13
(a) Effective Date
(g) Required Action
Within 25 engine operating hours after the
effective date of this AD, remove the
crankshaft assembly from service.
(h) Special Flight Permit
A one-time special flight permit may be
issued to fly the aircraft to a maintenance
facility to perform the actions of this AD with
the following limitations: No passengers,
visual flight rules (VFR) day conditions only,
and avoid areas of known turbulence.
PO 00000
Frm 00055
Fmt 4700
Sfmt 4700
79833
(i) Alternative Methods of Compliance
(AMOCs)
(1) The Manager, Fort Worth ACO 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
certification office, send it to the attention of
the person identified in Related Information.
(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.
(j) Related Information
For more information about this AD,
contact Justin Carter, Aviation Safety
Engineer, Fort Worth ACO Branch, FAA,
10101 Hillwood Parkway, Fort Worth, TX
76177; phone: (817) 222–5146; fax: (817)
222–5245; email: justin.carter@faa.gov.
(k) Material Incorporated by Reference
None.
Issued on December 3, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness
Division, Aircraft Certification Service.
[FR Doc. 2020–27149 Filed 12–10–20; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 71
[Docket No. FAA–2020–0726; Airspace
Docket No. 20–AGL–28]
RIN 2120–AA66
Amendment of Class E Airspace;
Cairo, IL
Federal Aviation
Administration (FAA), DOT.
ACTION: Final rule.
AGENCY:
This action amends Class E
airspace extending upward from 700
feet above the surface at Cairo Regional
Airport, Cairo, IL. This action is the
result of an airspace review caused by
the decommissioning of the Cape
Girardeau very high frequency
omnidirectional range (VOR)
navigational aid as part of the VOR
Minimum Operational Network (MON)
Program. The name and geographic
coordinates of the airport are updated to
coincide with the FAA’s aeronautical
database.
SUMMARY:
Effective 0901 UTC, February 25,
2021. The Director of the Federal
Register approves this incorporation by
reference action under Title 1 Code of
DATES:
E:\FR\FM\11DER1.SGM
11DER1
Agencies
[Federal Register Volume 85, Number 239 (Friday, December 11, 2020)]
[Rules and Regulations]
[Pages 79828-79833]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-27149]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2018-1077; Project Identifier 2018-NE-40-AD; Amendment
39-21354; AD 2020-25-12]
RIN 2120-AA64
Airworthiness Directives; Superior Air Parts, Inc. Engines and
Lycoming Engines Reciprocating Engines With a Certain SAP Crankshaft
Assembly
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all
Superior Air Parts, Inc. (SAP) Model IO-360-series and O-360-series
reciprocating engines and certain Lycoming Engines (Lycoming) Model
AEIO-360-, IO-360-, and O-360-series reciprocating engines with a
certain SAP crankshaft assembly installed. This SAP crankshaft assembly
is installed as original equipment on the affected SAP engines and as a
replacement part under parts manufacturer approval (PMA) on the
affected Lycoming engines. This AD was prompted by three crankshaft
assembly failures that resulted in the loss of engine power and
immediate or emergency landings. This AD requires the removal from
service of all affected crankshaft assemblies. The FAA is issuing this
AD to address the unsafe condition on these products.
DATES: This AD is effective January 15, 2021.
Examining the AD Docket
You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2018-1077; 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, any
comments received, and other information. The address for Docket
Operations is 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: Justin Carter, Aviation Safety
Engineer, Fort Worth ACO Branch, FAA, 10101 Hillwood Parkway, Fort
Worth, TX 76177; phone: (817) 222-5146; fax: (817) 222-5245; email:
[email protected].
SUPPLEMENTARY INFORMATION:
[[Page 79829]]
Background
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to all SAP Model IO-360-
series and O-360-series reciprocating engines and certain Lycoming
Model AEIO-360-, IO-360-, and O-360-series reciprocating engines with a
certain SAP crankshaft assembly installed. The NPRM published in the
Federal Register on January 29, 2020 (85 FR 5173). The NPRM was
prompted by three crankshaft assembly failures that resulted in the
loss of engine power and immediate or emergency landings. The FAA
determined that the crankshaft assembly failures resulted from the
manufacturing process at SAP's crankshaft vendor during 2012 and 2014
causing excessive residual white layer of iron nitride forming on the
assemblies. This white layer is brittle and can lead to spalling or
fatigue cracking of the crankshaft assembly as a result of the normal
mechanical loads during engine operation. The FAA's analysis concluded
that all three SAP crankshaft assembly failures were the result of this
fatigue cracking. In the NPRM, the FAA proposed to require the removal
from service of all affected crankshaft assemblies. The unsafe
condition, if not addressed, could result in failure of the engine, in-
flight shutdown, and loss of the airplane.
Discussion of Final Airworthiness Directive Comments
The FAA received comments from seven commenters. The commenters
were SAP, the Aircraft Owners and Pilots Association (AOPA), and five
individual commenters. Three commenters requested that the FAA extend
the comment period. One commenter requested the withdrawal of the AD.
Two commenters asked the FAA to release more information. One commenter
asked for the status of the AD and if the crankshaft assembly is safe
to fly. The following presents the comments received on the NPRM and
the FAA's response to each comment.
Request To Withdraw the NPRM: White Layer Does Not Contribute to
Fracture
SAP stated that data from an independent laboratory test does not
support the statement in the NPRM that the crankshaft failures were a
result of residual white layer formation, also known as a compound
layer, on certain crankshaft assemblies as a result of improper
manufacturing by a third-party vendor. SAP stated that the fractured
crankshafts were all within specifications. SAP found both the material
and the heat treatment to be within all engineering requirements and
consistent with other crankshafts in general aviation piston aircraft
engines. SAP noted that these requirements were consistent with the
engineering testing conducted by SAP in pursuit of FAA PMA
certification. Additionally, SAP stated the fractures were not
consistent with fatigue fractures due to excessive white layer, and
that no manufacturing or material defect was found in independent
metallurgical laboratory analysis. The FAA infers from this comment
that SAP is requesting that the FAA withdraw the NPRM.
The FAA disagrees with SAP's analysis. BakerRisk Project No. 01-
05929-003-17, dated August 15, 2017, for SAP crankshaft assembly S/N
SP14-0202, which failed on March 6, 2017, found that there was a
continuous white layer at the surface of the radius, extending up to
the location of the fracture, and that the white layer may have
contributed to early crack initiation. \1\ The continuous white layer
at the origin was 0.0007 inch. BakerRisk Project No. 01-05929-006-17,
Rev. 1, dated May 8, 2018, for SAP crankshaft assembly S/N SP14-0194,
which failed on August 3, 2017, found that the continuous white layer
at the surface of the forward journal radius, extending up to the
location of the fracture, was 0.0006 inch. According to the report,
this indicates that the process being used to remove the white layer
was not removing the entire white layer. Because it found that the
presence of the white layer can lower fatigue resistance and result in
premature fatigue crack initiation, the report included recommendations
to review the material and the processes that define the crankshaft
journals, especially the nitride case hardening and white layer removal
process. \2\
---------------------------------------------------------------------------
\1\ See pp. 2-3 of BakerRisk Project No. 01-05929-003-17.
\2\ See pp. 4-5 of BakerRisk Project No. 01-05929-006-17, Rev.
1.
---------------------------------------------------------------------------
SAP's comment cited Hurst Metallurgical Research Laboratory, Inc.,
(Hurst) Report No. 73900, dated February 22, 2019, for SAP crankshaft
assembly S/N SP13-0150, which failed on October 31, 2018. This Hurst
report found that the continuous white layer of iron nitride at the
surface of the forward journal radius was 0.0001 inch. The FAA,
however, disagrees with the reported thickness of the white layer. The
report includes two scaled photographs (photographs No. 11 and 12),
magnified 100 times and 500 times, respectively. Using the scaling bar
provided in the photographs, the FAA determined that the white layer is
0.0009 inch. Although SAP stated a white layer of up to 0.001 inch is
allowed, SAP based this figure on an SAE Aerospace Material
specification and not on the original equipment manufacturer's (OEM)
specifications. A white layer of 0.0009 inch exceeds the amount allowed
by the OEM.
As supported by the reports, the FAA finds that white layer
contributed to the early crack initiation and, on all failed crankshaft
assemblies, exceeded OEM specifications. Based on the foregoing, the
FAA finds no basis to withdraw the NPRM.
Request To Withdraw the NPRM: White Layer Does Not Increase Fatigue
Resistance
SAP stated that the presence of a white layer does not reduce the
fatigue resistance of material at the surface, but rather increases the
fatigue resistance of that same material. SAP cited a study by Major,
Jakl, and Hub[aacute]lovsk[yacute] for the observation that the
application of plasma carburizing can lead to about a 25% increase in
fatigue resistance.\3\ SAP stated a study by Hiraoka and Ishida \4\
shows a marked increase in fatigue limit in a specimen with a 10 [mu]m
thick white layer as opposed to a specimen without a white layer, with
a slight increase in the fatigue limit in a specimen with a 20 [mu]m
thick white layer as compared to the specimen with a 10 [mu]m thick
white layer. The FAA infers from this comment that SAP is requesting
that the FAA withdraw the NPRM.
---------------------------------------------------------------------------
\3\ [Scaron]tep[aacute]n Major, Vladimir Jakl, &
[Scaron]tep[aacute]n Hub[aacute]lovsk[yacute], Effect of carburizing
on fatigue life of high-strength steel specimen under push-pull
loading, Advances in Engineering Mechanics and Materials, 143
(2014).
\4\ Yaushi Hiraoka & Akihiro Ishida, Effect of Compound Layer
Thickness Composed of [gamma]'-Fe4N on Rotated-Bending Fatigue
Strength in Gas-Nitrided JIS-SCM435 Steel, 58 MATERIALS TRANSACTIONS
993 (2017).
---------------------------------------------------------------------------
The FAA disagrees with the applicability of these studies to the
unsafe condition identified in this AD. Although the application of
plasma carburizing can lead to an increase in the fatigue resistance,
the affected crankshaft assemblies were not plasma carburized.
Therefore, the Major, Jakl, and Hub[aacute]lovsk[yacute] study is not
relevant here. Although the Hiraoka and Ishida study did reveal an
increase in fatigue limit of gas nitrided steel with a white layer over
one without a white layer, the study's test environment did not
replicate the conditions applicable to an engine crankshaft as
identified in Advisory Circular No. 33.19-1, ``Guidance Material for 14
CFR Sec. 33.19, Durability, for Reciprocating Engine Redesigned
Parts,'' dated September 27,
[[Page 79830]]
2004 (AC 33.19-1). A crankshaft is a part whose primary fatigue
mechanism is a forced vibratory response in combination with a resonant
vibratory response that occurs at any engine speed at which the natural
frequency of the part (or assembly that includes the part) coincides
with the frequency of a combustion or inertia harmonic. AC 33.19-1
recommends 300 hours of engine tests, including a vibration test at
peak torsional resonance conditions, to test the fatigue strength of
the crankshaft.
The white layer is well-established to be problematic in that it is
brittle. The OEM removes the white layer during the manufacturing
process. As a PMA holder, 14 CFR 21.303 requires that SAP produce a
part that is equivalent to the OEM part. Based on the foregoing, the
FAA finds no basis to withdraw the NPRM.
Request To Withdraw the NPRM: Operation Outside of Normal Conditions
SAP stated the fractures of the crankshaft assemblies cited in the
NPRM were due to misuse, abuse, or lack of lubrication. In support, SAP
cited Hurst Report No. 73614, Rev. 1, dated December 7, 2018, for SAP
crankshaft assembly S/N SP14-0202 and Hurst Report No. 73617, Rev. 1,
dated December 7, 2018, for SAP crankshaft assembly S/N SP14-0194,
which indicate that the fractures were likely initiated by abnormal
service conditions, such as a propeller strike and a start-up of the
engine in a low-temperature (below optimal performing temperature)
environment. SAP also cited Hurst Report No. 73900 for SAP crankshaft
assembly S/N SP13-0150, which indicates that likely contributors of the
failure include rod sliding bearing failure due to insufficient
lubrication, misalignment of the crankshaft, and improper engine
performance from inadequate operation procedure resulting in high
bending moment at the radius locations from excessive force from the
piston assembly. SAP stated that all three of these crankshafts were
operated in a flight school environment. The FAA infers from this
comment that SAP is requesting that the FAA withdraw the NPRM.
The FAA disagrees that the fracture was initiated by the operation
of the engines outside of ``normal'' conditions or parameters. With
respect to Hurst Report No. 73614 for SAP crankshaft assembly S/N SP14-
0202 and Hurst Report No. 73617 for SAP crankshaft assembly S/N SP14-
0194, none of the engines exhibited evidence of propeller strikes, and
none were started below optimal performance temperature. According to
Lycoming,\5\ cold weather requiring the use of pre-heat to avoid a cold
engine start-up is 10 degrees Fahrenheit or below. Two of the incidents
occurred in August (Canada) and October (Florida), making cold engine
start-up unlikely. The third incident occurred in March
(Massachusetts), which had a low of 16 degrees Fahrenheit at 6 a.m. and
proceeded to a high of 41 degrees Fahrenheit in the afternoon.
---------------------------------------------------------------------------
\5\ Lycoming Service Instruction No. 1505, dated July 1, 2002:
``The use of pre-heat will facilitate starting during cold weather,
and is required when the engine has been allowed to drop to
temperatures below +10 [deg]F/-12 [deg]C.''
---------------------------------------------------------------------------
With respect to Hurst Report No. 73900 for SAP crankshaft assembly
S/N SP13-0150, the pilot and mechanic separately reported the engine
had good oil pressure, indicating that the engine did not suffer from a
lack of proper lubrication at the time of the crankshaft assembly
failure. The report identifies possible contributors of single origin
fatigue failure, including the misalignment of the crankshaft assembly
or improper engine performance from inadequate operation procedure
resulting in high bending moment at the radius locations from excessive
force from the piston assembly. However, the report does not provide
evidence to support these contributors. Based on the foregoing, the FAA
declines to withdraw the NPRM.
Request To Review National Transportation Safety Board (NTSB) Reports
An individual commenter requested to review the NTSB reports on the
accidents mentioned in the NPRM. The commenter was unable to locate
anything in the NTSB database concerning engine stoppage in aircraft
powered by Lycoming or SAP O-360 or IO-360 engines.
The NTSB did not generate reports for the three incidents that
resulted from the crankshaft failures discussed in the NPRM. Therefore,
the FAA did not rely on NTSB reports and is not in possession of any
report generated as a result of the three incidents.
Request To Add Metallurgical Analyses to the Docket
An individual commenter requested that the FAA add its
metallurgical analyses to the docket. The commenter stated that it was
his understanding from discussions with the FAA that the FAA has shared
its metallurgical analyses with SAP.
The FAA agrees and has uploaded the BakerRisk and Hurst
metallurgical reports provided by SAP to the AD docket, as SAP has
agreed to release these reports to the public. The FAA, however, did
not perform its own metallurgical testing. The FAA instead relied on
metallurgical testing performed by BakerRisk and Hurst for SAP.
Request To Release Pertinent Information
An individual commenter requested that the FAA release information
it has on this issue, including the circumstances of the crankshaft
assembly failures, the cost of crankshaft assembly replacement, and the
scope of the proposed action.
The FAA agrees to provide additional information about the
circumstances of the failures. In each incident, the crankshaft
assembly broke into two pieces. The March 6, 2017, incident resulted in
the crankshaft separating at journal #2 while the August 3, 2017, and
October 31, 2018, incidents both resulted in a separation of the
crankshaft at journal #4. All of the incidents involved flight-training
aircraft. Additionally, as discussed previously, the FAA has uploaded
the metallurgical reports to the AD docket.
Both the NPRM and this final rule adequately explain the scope of
the AD and contain a detailed estimate of the costs of compliance
within this AD, including the cost of the crankshaft assembly
replacement, labor cost, and total estimated cost to U.S. operators.
This final rule also discusses the net benefit of this AD.
Request To Consider Costs of Implementing This AD
An individual commenter requested that the FAA consider the
financial costs and unintended consequences of this AD, such as
decreased aircraft value. The commenter estimates that the value of his
aircraft has been reduced by at least $15,000 since the publication of
the NPRM.
The FAA disagrees. The cost analysis in AD rulemaking actions
typically includes only the costs associated with complying with the AD
and does not include indirect costs such as loss of aircraft value. The
FAA acknowledges that the general obligation of the operator to
maintain its aircraft in an airworthy condition is sometimes expensive.
However, and as discussed in more detail in the Benefits section, the
FAA estimates that the benefits of this AD greatly exceed its cost.
[[Page 79831]]
Request To Clarify Applicability
An individual commenter asked if SAP crankshaft assemblies earlier
than 2012 are affected by this AD.
The first affected SAP crankshaft assembly was shipped on July 31,
2012. SAP crankshaft assemblies assembled before July 31, 2012, are not
affected by this AD.
Request To Extend Comment Period
SAP and AOPA requested that the FAA extend the comment period by 60
days to enable SAP to gather more information. SAP asked for more time
to research, gather, and respond appropriately to the NPRM. AOPA
similarly requested an extension to review the costs and overall scope,
and to gather information to respond to the NPRM. SAP, AOPA, and an
individual commenter requested the FAA extend the comment period
because of delays due to the COVID-19 pandemic, such as the closure of
laboratories for further testing and the reduction in aircraft
operations.
The FAA disagrees. At SAP's request, the FAA met with SAP and AOPA
in April 2020 to discuss the NPRM. During that meeting, the
participants discussed certain aspects of the NPRM, including the white
layer and metallurgical reports, the three failed crankshaft
assemblies, and SAP's request for a 60-day extension to the comment
period. A summary of the meeting is available in the AD docket. None of
the information provided by SAP or AOPA justifies an extension of the
comment period. If investigations by SAP or others reveal information
that changes the FAA's determination regarding the unsafe condition,
the FAA will consider future rulemaking.
Request for a Status Update
An individual commenter requested information regarding the FAA's
progress on issuing this AD. The commenter stated that based on
feedback from SAP, the crankshaft assembly is safe and that a
metallurgy company inspected one of the affected crankshaft assemblies
and did not find any issues.
The FAA disagrees with the assessment from SAP. The FAA reviewed
the metallurgical reports from the incidents of failed crankshaft
assemblies and determined that an unsafe condition exists in other
crankshaft assemblies of the same type design. In each incident, the
crankshaft assembly broke into two pieces, leading to loss of engine
power. The crankshaft assemblies involved in the three incidents were
found to have excessive white layer. As a result, this AD requires
removing all affected crankshaft assemblies from service within 25
engine operating hours after the effective date of this AD.
Conclusion
The FAA reviewed the relevant data, considered the comments
received, and determined that air safety requires adopting the AD as
proposed. Accordingly, the FAA is issuing this AD to address the unsafe
condition on these products.
Regulatory Flexibility Determination
The Regulatory Flexibility Act of 1980 (Pub. L. 96-354, codified as
amended at 5 U.S.C. 601-612) (RFA) establishes ``as a principle of
regulatory issuance that agencies shall endeavor, consistent with the
objectives of the rule and of applicable statutes, to fit regulatory
and informational requirements to the scale of the businesses,
organizations, and governmental jurisdictions subject to regulation. To
achieve this principle, agencies are required to solicit and consider
flexible regulatory proposals and to explain the rationale for their
actions to assure that such proposals are given serious
consideration.'' Public Law 96-354, 2(b), September 19, 1980. The RFA
covers a wide-range of small entities, including small businesses, not-
for-profit organizations, and small governmental jurisdictions.
Agencies must perform a review to determine whether a rule will have a
significant economic impact on a substantial number of small entities.
If the agency determines that it will, the agency must prepare a
regulatory flexibility analysis as described in the RFA.
The FAA published an Initial Regulatory Flexibility Analysis (IRFA)
in the proposed rule to aid the public in commenting on the potential
impacts to small entities. The FAA considered the public comments in
developing the final rule and this Final Regulatory Flexibility
Analysis (FRFA).
Benefits
The FAA found that SAP, the manufacturer of the crankshaft
assemblies, sold 192 SAP crankshaft assemblies to date: 115 of these
crankshaft assemblies are estimated to be installed on type
certificated airplanes and the remaining 77 crankshaft assemblies are
estimated to be installed on experimental aircraft. The FAA's risk
analysis indicates that 100 percent of crankshaft assembly failures
will destroy the engine. Using the historical incident data (2000-
2014), the FAA assumes that 24.4 percent of crankshaft assembly
failures will result in aircraft hull loss while 22 percent of
crankshaft assembly failures will result in fatalities. There would be
an average of 2.1 fatalities per each crankshaft assembly accident.
Applying these probabilities to the estimated 115 crankshaft assemblies
installed on type certificated airplanes, the FAA estimates that if
these crankshaft assemblies are not replaced and continue to be used in
these airplanes, this will result in 53 fatalities (2.1 fatalities per
crankshaft accident x 22 percent probability of a crankshaft assembly
failure resulting in fatalities x 115 crankshaft assemblies) and 28
aircraft losses (24.4 percent probability of a crankshaft assembly
failure destroying the airplane). This AD will prevent all 53
fatalities and 28 aircraft losses.
Using an average price of $50,000 for a small single engine
airplane, an average price of $30,000 for a 360-series engine and the
Department of Transportation's $9.6 million estimate for the Value of
Statistical Life (VSL) from the ``Revised Departmental Guidance on
Valuation of a Statistical Life in Economic Analysis,'' \6\ the FAA
estimated this AD final rule will result in monetized benefits of
$512.8 million. \7\
---------------------------------------------------------------------------
\6\ https://www.transportation.gov/office-policy/transportation-policy/revised-departmental-guidance-on-valuation-of-a-statistical-life-in-economic-analysis.
\7\ 53 preventable fatalities will amount to $508.8 million in
benefits of this rule. (53 x $9.6 million). The value of 28 airplane
losses is $1.4 million (28 x $50,000). The remaining 75.6 percent of
crankshaft failures (100 percent-24.4 percent crankshaft failure
destroying the airplane) will result in $2.6 million in engine
damages. (115 x 0.756 probability of crankshaft failure damaging an
airplane engine x $30,000 value of 360 engine). Therefore, the total
estimated benefits are $512.8 million ($508.8 million preventable
fatalities + $1.4 million avoidable airplane loss + $2.6 million
preventable engine damages).
---------------------------------------------------------------------------
Costs of Compliance
The costs of compliance with this AD consist of the cost to remove
and replace a crankshaft assembly. The FAA estimates that this AD will
affect 115 crankshaft assemblies installed on airplanes of U.S.
registry. This cost estimate does not include 77 SAP crankshaft
assemblies installed on experimental engines since this AD does not
apply to these engines. The estimated compliance cost per crankshaft
assembly is identified below.
Labor cost = 61 hours per crankshaft assembly replacement x $85
Hourly Wage = $5,185.
Equipment costs per crankshaft assembly replacement = $9,636
(Source: Average of the two vendors).
$5,185 labor per crankshaft assembly + $9,636 equipment costs per
crankshaft
[[Page 79832]]
assembly replacement = $14,821 compliance cost per engine.
The total costs to U.S. operators is $1,704,415 ($14,821 x 115), or
$119,309 in annualized costs in perpetuity using a 7 percent discount
rate. There are no additional costs after removing and replacing the
crankshaft assembly.
Therefore, the FAA estimates that the net benefit of this final
rule will be $511.1 million ($512.8 million benefits -$1.7 million
costs), or $35.77 million in annualized net benefits using a 7 percent
discount rate in perpetuity.
Final Regulatory Flexibility Analysis
Under Sec. 604(a) of the RFA, the final analysis must contain the
following:
(1) A statement of the need for, and objectives of, the rule;
(2) A statement of the significant issues raised by the public
comments in response to the IRFA, a statement of the assessment of the
agency of such issues, and a statement of any changes made in the
proposed rule as a result of such comments;
(3) The response of the agency to any comments filed by the Chief
Counsel for Advocacy of the Small Business Administration (SBA) in
response to the proposed rule, and a detailed statement of any change
made to the proposed rule in the final rule as a result of the
comments;
(4) A description of and an estimate of the number of small
entities to which the rule will apply or an explanation of why no such
estimate is available;
(5) A description of the projected reporting, record-keeping, and
other compliance requirements of the proposed rule, including an
estimate of the classes of small entities which will be subject to the
requirement and the type of professional skills necessary for the
preparation of the report or record;
(6) A description of the steps the agency has taken to minimize the
significant economic impact on small entities consistent with the
stated objectives of applicable statutes, including a statement of the
factual, policy, and legal reasons for selecting the alternative
adopted in the final rule and why each of the other significant
alternatives to the rule considered by the agency which affect the
impact on small entities was rejected.
1. Need for and Objectives of the Rule
This final rule AD was prompted by three crankshaft assembly
failures that resulted in the loss of engine power and immediate or
emergency landings. The FAA is issuing this AD to prevent failure of
the crankshaft assembly by requiring the removal of all affected
crankshaft assemblies from service. Failure of a crankshaft assembly,
if not addressed, could result in failure of the engine, in-flight
shutdown, and loss of the airplane.
2. Significant Issues Raised in Public Comments
An individual commenter noted that some owners of affected aircraft
may not be in a position to absorb the $15,000 cost of the crankshaft
assembly replacement. The commenter proposed that the financial costs
of this AD would exceed the FAA estimates in some cases and, therefore,
the unintended consequences of this AD would destroy value out of
proportion to the preservation of the safety of the national airspace
system and the general public.
The FAA estimates the cost of replacing a single crankshaft
assembly at $14,821. The risk of not replacing the crankshaft is not
insignificant, and the crankshaft failure could cause engine loss,
airplane loss, or fatality valued at $30,000, $50,000, and $9.6
million, respectively. When these potentially substantial losses and
risks of fatality to each airplane owner and operator are considered,
the $14,821 compliance cost per airplane is minimal. Further, the FAA
estimates the benefits of this AD to be $512.8 million, which greatly
exceeds its cost of $1.7 million, justifying this final rule.
Based on the risk and benefits analysis above, the FAA determined
that no changes are necessary to the final rule as a result of this
individual comment.
3. Response to SBA Comments
The Chief Counsel for Advocacy of the SBA did not file any comments
in response to the proposed rule.
4. Small Entities to Which the Rule Will Apply
This AD applies to all SAP Model IO-360-series and O-360-series
reciprocating engines and certain Lycoming Model AEIO-360-, IO-360-,
and O-360-series reciprocating engines with a certain SAP crankshaft
assembly installed. This SAP crankshaft assembly is installed as
original equipment on the affected SAP engines and as a replacement
part under PMA on the affected Lycoming engines. These engines are
installed on airplanes performing various activities including, but not
limited to, flight training, charter flights, and agriculture.
Under the RFA, the FAA must determine whether a final rule
significantly affects a substantial number of small entities. The FAA
uses the SBA criteria for determining whether an affected entity is
small. For aircraft and engine manufacturers, aviation operators, and
any business using an aircraft, the SBA criterion is 1,500 or fewer
employees. The FAA estimates that this AD affects 115 crankshaft
assemblies installed on airplanes of U.S. registry. The FAA does not
have any information or data on whether these entities are small
businesses according to the definition established by the SBA. Although
in the NPRM the FAA requested comments and data that would allow the
agency to more accurately assess the number of employees and sales
revenues of the affected entities, no such comments or data was
received. Accordingly, the FAA assumes for purposes of this final rule
that some of the affected entities are small businesses.\8\ The FAA
determines that the estimated $14,821 compliance cost per aircraft due
to this rule will have a significant impact on a substantial number of
small entities.
---------------------------------------------------------------------------
\8\ The FAA recognizes that many of these affected airplanes are
recreational. The 2016 GAMA Databook shows that of 141,141 active
General Aviation piston aircraft, 104,669 are used for personal or
recreational purposes (74 percent), Using this distribution, only 30
of the 115 crankshaft assemblies would be installed in airplanes
operated for business use.
---------------------------------------------------------------------------
5. Projected Reporting, Record-Keeping, and Other Compliance
Requirements
There are no record-keeping costs or other compliance costs
associated with this final rule.
6. Significant Alternatives Considered
As part of the FRFA, the FAA is required to consider regulatory
alternatives that may be less burdensome. The FAA considered the
following alternatives:
Do nothing: This option is not acceptable because the risk of
additional failures of these crankshaft assemblies constitutes a known
unsafe condition. The FAA estimates that this AD will prevent 53
fatalities and 28 aircraft losses, and monetized benefits of $512.8
million.
Periodic inspections: This option is not possible as the crankshaft
assembly cannot be inspected without destroying it.
There is no direct safety alternative to the replacement of the
crankshaft assembly. The replacement addresses a safety issue aimed at
preventing the failure of the crankshaft assembly.
Therefore, the FAA rejected these two regulatory alternatives and
determined that this rulemaking may have a significant economic impact
on a substantial number of small entities.
[[Page 79833]]
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
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 above, I certify that this AD:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866, and
(2) Will not affect intrastate aviation in Alaska.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
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:
2020-25-12 Superior Air Parts, Inc.: Amendment 39-21354; Docket No.
FAA-2018-1077; Project Identifier 2018-NE-40-AD.
(a) Effective Date
This airworthiness directive (AD) is effective January 15, 2021.
(b) Affected ADs
None.
(c) Applicability
This AD applies to the reciprocating engine models identified in
paragraphs (c)(1) and (2) of this AD with a Superior Air Parts, Inc.
(SAP) crankshaft assembly, part number (P/N) SL36500-A20 or P/N
SL36500-A31, with serial numbers 82976-01; 82976-02; SP12-0003
through SP12-0089, inclusive; SP13-0034 through SP13-0150,
inclusive; or SP14-0151 through SP14-0202, inclusive; installed.
(1) With SAP crankshaft assembly, P/N SL36500-A20, installed:
(i) SAP Model IO-360-series and O-360-series reciprocating
engines.
(ii) Lycoming Engines (Lycoming) Model IO-360-B2F, IO-360-L2A,
O-360, O-360-A2A, O-360-A2D, O-360-A2E, O-360-A2F, O-360-A2G, O-360-
B2A, O-360-C2A, O-360-C2C, O-360-C2D, O-360-C2E, O-360-D2A, and O-
360-D2B reciprocating engines.
(2) With SAP crankshaft assembly, P/N SL36500-A31, installed:
(i) SAP Model IO-360-series and O-360-series reciprocating
engines.
(ii) Lycoming Model AEIO-360-H1A, IO-360-B1A, IO-360-B1B, IO-
360-B1D, IO-360-B1E, IO-360-B1F, IO-360-M1A, O-360, O-360-A1A, O-
360-A1C, O-360-A1D, O-360-A2A, O-360-C1A, O-360-C1G, O-360-C1C, O-
360-C1E, and O-360-C1F reciprocating engines.
Note 1 to paragraph (c): This SAP crankshaft assembly may be
installed as a replacement part under parts manufacturer approval on
the affected Lycoming engines.
(d) Subject
Joint Aircraft System Component (JASC) Code 8520, Reciprocating
Engine Power Section.
(e) Unsafe Condition
This AD was prompted by three crankshaft assembly failures that
resulted in the loss of engine power and immediate or emergency
landings. The FAA is issuing this AD to prevent failure of the
crankshaft assembly. The unsafe condition, if not addressed, could
result in failure of the engine, in-flight shutdown, and loss of the
airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Required Action
Within 25 engine operating hours after the effective date of
this AD, remove the crankshaft assembly from service.
(h) Special Flight Permit
A one-time special flight permit may be issued to fly the
aircraft to a maintenance facility to perform the actions of this AD
with the following limitations: No passengers, visual flight rules
(VFR) day conditions only, and avoid areas of known turbulence.
(i) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Fort Worth ACO 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 certification office, send it to the attention of
the person identified in Related Information.
(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.
(j) Related Information
For more information about this AD, contact Justin Carter,
Aviation Safety Engineer, Fort Worth ACO Branch, FAA, 10101 Hillwood
Parkway, Fort Worth, TX 76177; phone: (817) 222-5146; fax: (817)
222-5245; email: [email protected].
(k) Material Incorporated by Reference
None.
Issued on December 3, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification
Service.
[FR Doc. 2020-27149 Filed 12-10-20; 8:45 am]
BILLING CODE 4910-13-P