80 FR 52212 - Airworthiness Directives; Continental Motors, Inc. Reciprocating Engines

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration

Federal Register Volume 80, Issue 167 (August 28, 2015)

Page Range52212-52215
FR Document2015-21205

We are revising an earlier proposed airworthiness directive (AD) for certain Airmotive Engineering Corp. (AEC) replacement parts manufacturer approval (PMA) cylinder assemblies marketed by Engine Components International Division (ECi). We subsequently issued an initial supplemental NPRM (SNPRM) that proposed to modify the schedule for removal of the affected cylinder assemblies, added that overhauled affected cylinder assemblies be removed within 80 hours, eliminated a reporting requirement, and removed a requirement for initial and repetitive inspections. This second SNPRM reopens the comment period to allow the public the chance to comment on additional information added to the docket of this proposed rule. We are proposing this SNPRM to prevent failure of the cylinder assemblies, which could lead to failure of the engine, in-flight shutdown, and loss of control of the airplane.

Federal Register, Volume 80 Issue 167 (Friday, August 28, 2015)
[Federal Register Volume 80, Number 167 (Friday, August 28, 2015)]
[Proposed Rules]
[Pages 52212-52215]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2015-21205]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0002; Directorate Identifier 2011-NE-42-AD]
RIN 2120-AA64


Airworthiness Directives; Continental Motors, Inc. Reciprocating 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (NPRM); reopening of 
comment period.

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SUMMARY: We are revising an earlier proposed airworthiness directive 
(AD) for certain Airmotive Engineering Corp. (AEC) replacement parts 
manufacturer approval (PMA) cylinder assemblies marketed by Engine 
Components International Division (ECi). We subsequently issued an 
initial supplemental NPRM (SNPRM) that proposed to modify the schedule 
for removal of the affected cylinder assemblies, added that overhauled 
affected cylinder assemblies be removed within 80 hours, eliminated a 
reporting requirement, and removed a requirement for initial and 
repetitive inspections. This second SNPRM reopens the comment period to 
allow the public the chance to comment on additional information added 
to the docket of this proposed rule. We are proposing this SNPRM to 
prevent failure of the cylinder assemblies, which could lead to failure 
of the engine, in-flight shutdown, and loss of control of the airplane.

DATES: We must receive comments on this SNPRM by September 28, 2015.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this proposed AD, contact 
Engine Components International Division, 9503 Middlex Drive, San 
Antonio, TX 78217; phone: 210-820-8101; Internet: http://www.eci.aero/pages/tech_svcpubs.aspx. You may view this service information at the 
FAA, Engine & Propeller Directorate, 12 New England Executive Park, 
Burlington, MA. For information on the availability of this material at 
the FAA, call 781-238-7125.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2012-
0002; or in person at the Docket Management Facility between 9 a.m. and 
5 p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this proposed AD, the regulatory evaluation, any comments 
received, and other information. The street address for the Docket 
Office (phone: 800-647-5527) is in the ADDRESSES section. Comments will 
be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Jurgen E. Priester, Aerospace 
Engineer, Delegation Systems Certification Office, FAA, Rotorcraft 
Directorate, 2601 Meacham Blvd., Fort Worth, TX 76137; phone: 817-222-
5190; fax: 817-222-5785; email: [email protected].

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2012-0002; 
Directorate Identifier 2011-NE-42-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We issued an NPRM to amend 14 CFR part 39 by adding an AD that 
would apply to certain AEC replacement PMA cylinder assemblies marketed 
by ECi. These assemblies are used on Continental Motors, Inc. (CMI) 
model 520 and 550 reciprocating engines, and all other CMI engine 
models approved for the use of models 520 and 550 cylinder assemblies 
such as the CMI model 470 when modified by STC. The NPRM published in 
the Federal Register on August 12, 2013 (78 FR 48828). The NPRM 
proposed to require initial and repetitive inspections, immediate 
replacement of cracked cylinder assemblies, and replacement of cylinder 
assemblies at reduced times-in-service (TIS) since new. The NPRM also 
proposed to prohibit the installation of affected cylinder assemblies 
into any engine.
    We subsequently issued an SNPRM which published in the Federal 
Register on January 8, 2015 (80 FR 1008). The SNPRM proposed a modified 
schedule for removal of the affected cylinder assemblies, added that 
overhauled affected cylinder assemblies be removed within 80 hours, 
eliminated a reporting requirement, and removed the requirement for 
initial and repetitive inspections.

Actions Since Previous SNPRM Was Issued

    Since we issued the SNPRM (80 FR 1008, January 8, 2015), we 
received numerous additional comments on the proposed rule. After 
reviewing the comments, we decided to reopen the docket so that we 
could provide additional information to explain the rationale for this 
AD action. We also wanted to provide commenters with the opportunity to 
comment on this additional information. We added the following 
information to Docket No. FAA-2012-0002: (1) The risk analysis 
conducted by the FAA's Chief Scientific and Technical Adviser, Aircraft 
Safety Analysis; (2) a risk analysis using the Small Airplane Risk 
Analysis methods; (3) a June 2011, presentation by Airmotive 
Engineering to the FAA

[[Page 52213]]

concerning its ECi cylinder assemblies; (4) a list of ECi cylinder 
assembly failure reports consisting of only those reports where both 
cylinder serial number and Time in Service are included in the reports; 
(5) a list of additional failures of ECi cylinder assemblies reported 
by a maintenance organization; (6) copies of the slides discussed with 
the NTSB on June 9, 2015 during the meeting with the NTSB to understand 
its comments to 2011-NE-42-AD, and (7) Airmotive Engineering 
Corporation Technical Report 1102-13, dated April 30, 2011.
    In addition, we met with National Transportation Safety Board 
(NTSB) representatives on June 9, 2015, to clarify the NTSB's basis for 
its comments of FAA's actions in this proposed rule.
    We are taking this opportunity to respond to a limited number of 
comments. Specifically, we found that numerous commenters cited 
differences between the FAA's proposed action and the NTSB's 
recommendations in NTSB Safety Recommendation A-12-7. We will respond 
to remaining comments to the initial SNPRM (80 FR 1008, January 8, 
2015) and to this second SNPRM when we issue the final rule.

Comments to the Previous SNPRM

Request To Provide Supporting Information

    Danbury Aerospace, Inc., and others in their comments to the SNPRM 
(80 FR 1008, January 8, 2015), requested that we provide additional 
information that supports this AD action.
    We agree. We added our risk analyses and other technical 
information, such as the list of cylinder failures noted above and ECi 
Technical Report 1102-13 that supports this proposed rule, to Docket 
No. FAA-2012-0002 to help commenters and the general public understand 
the need for this proposed rule.

Request To Withdraw the SNPRM Because ECi Cylinder Assemblies Are Not 
Unsafe

    Several operators, maintenance organizations, and private citizens 
asked that we withdraw the SNPRM (80 FR 1008, January 8, 2015) because 
the affected ECi cylinder assemblies have an equivalent, or lower, 
failure rate than that of cylinder assemblies manufactured by the 
original equipment manufacturer (OEM).
    We disagree. We found that the failure rate for ECi cylinder 
assemblies is much higher than for OEM cylinder assemblies over the 
same period. Accident data confirms, that engines and airplanes may not 
always continue to operate safely with a separated cylinder and that 
separated cylinders have been the precipitating event in at least two 
fatal accidents. This accident data is included in the risk analyses 
that we uploaded to the docket (see NTSB Accident Identifiers 
NYC02FA178 and ERA11WA008, which are cited in these analyses). We did 
not withdraw this proposed rule.

Request To Review Comparison of Failure Rate Between OEM and ECi 
Cylinder Assemblies

    The NTSB commented that the comparison between failure rates of OEM 
and ECi cylinder assemblies was not valid because the cylinder heads 
represented substantially different designs.
    We disagree that the comparison between OEM and ECi cylinder 
assemblies is not valid. The ECi PMA design was reverse engineered by 
ECi from earlier vintage OEM cylinders, and uses the same time between 
overhaul (TBO) as the OEM cylinders. Since these ECi cylinder 
assemblies are approved to the same TBO as the OEM cylinders, the ECi 
cylinders should have durability that is equivalent to the OEM 
cylinders. Our comparison of ECi cylinder assembly service history with 
the OEM cylinder assembly history showed that the rate of separation 
for the affected ECi cylinder assemblies is at least 32 times greater 
than that of OEM cylinder assemblies over the same period. We uploaded 
this data for commenter review. It may be viewed in Docket No. FAA-
2012-0002. We did not change this proposed AD.

Request To Revise Applicability

    The NTSB commented that it has not investigated any cases involving 
engines with cylinder assemblies ranging from serial number (S/N) 1 
through S/N 1043. The NTSB indicated that cylinder assemblies in this 
S/N range should not be affected by the AD.
    We disagree. Cylinder assemblies with S/N 1 through S/N 1043 have 
the same design as noted in this SNPRM, exhibit the same unsafe 
condition, and therefore must be included in the applicability. We did 
not change this proposed AD.
    The NTSB also commented that AD 2004-08-10, which was issued on May 
5, 2004, requires replacement before further flight of ECi cylinder 
assemblies ranging from S/N 1044 through S/N 7708 installed on CMI 520 
and 550 series engines. According to AD 2004-08-10, ECi identified a 
manufacturing discrepancy that occurred between September 2002 and May 
2003 affecting cylinder assemblies S/N 1044 through S/N 7708, which 
resulted in an over-hardened condition that would reduce the fatigue 
strength of the aluminum cylinder head. The NTSB commented, therefore, 
that cylinder assemblies S/N 1044 through S/N 7708 should not be 
included in the proposed AD.
    We disagree. AD 2004-08-10 does not apply to all cylinder 
assemblies S/N 1044 through S/N 7708; it applies only to cylinder 
assemblies having specific cast markings. Cylinder assemblies S/N 1004 
through S/N 7708 have the same design as noted in this SNPRM, exhibit 
the same unsafe condition, and therefore must be included in the 
applicability. We did not change this proposed AD.
    The NTSB also commented that, based on its review of the additional 
seal band interference fit data provided by ECi, action is only 
required for 165 cylinder assemblies S/N 36210 through S/N 61176.
    We disagree. We have received reports of separations of cylinder 
assemblies S/N 36210 through S/N 61176 that were not among the 165 
cylinders that ECi claimed may be at risk for separation due to 
insufficient head to barrel interference fit. We have uploaded 
information in Docket No. FAA-2012-0002 that identifies S/Ns of failed 
cylinder assemblies that were not among the 165 cylinder assemblies 
identified by ECi. We did not change this proposed AD.
    The NTSB commented that the applicability represented by the 
SNPRM--S/N 1 through S/N 61176--represents a much larger number of 
affected cylinder assemblies than is supported by its investigations.
    We disagree. ECi's next increase in the design interference fit was 
incorporated beginning with S/N 61177. Consequently, all cylinder 
assemblies S/N 1 through S/N 61176 are at risk for separation in the 
first thread due to insufficient interference fit. We, therefore, find 
that based on service failure data, identified in the docket as ``U.S. 
DOT/FAA--04 ECi 520-550 Cylinder Separations,'' and ECI's 
implementation of design improvements, this proposed AD must apply to 
cylinder assemblies S/N 1 through S/N 61176. We did not change this 
proposed AD.

Request To Include Repetitive Inspection Requirement

    The NTSB commented that we should impose a repetitive inspection 
requirement for certain ECi cylinder assemblies and their removal once 
they reach the manufacturer's recommended TBO. This repetitive 
inspection requirement was part of the NPRM (78

[[Page 52214]]

FR 48828, August 12, 2013), but we removed it from the SNPRM (80 FR 
1008, January 8, 2015).
    The NTSB observed that the FAA had published Special Airworthiness 
Information Bulletin (SAIB) NE-07-09R1, dated March 21, 2007, and 
approved ECi Mandatory Service Bulletin 06-2, Revision 2, dated October 
26, 2006. Both of these documents emphasize the importance of 
conducting periodic inspections of ECi cylinder assemblies.
    We disagree. We have found, based on service experience since the 
publication of SAIB NE-07-09R1, that the inspection and tests are not 
reliable in detecting cracked cylinders and the cost associated with 
such ongoing tests outweighs the safety benefit. In addition, the crack 
propagation growth rate is unknown. As a result, we have received field 
reports of separated cylinders that occurred within the repetitive 50-
hour compression test and leak check inspection intervals proposed by 
the NPRM. We did not change this proposed AD.
    The NTSB also noted that repetitive inspections are not perfect but 
are still effective in detecting cracks that have propagated through 
the cylinder wall. These inspections provide an added level of safety 
from the time of the issuance of the final rule AD until the required 
removal of the cylinder assembly.
    We disagree. We find that repetitive inspections until TBO are 
inconsistent with the serious hazard represented by cylinder assembly 
failures. See the ``U.S. DOT/FAA-01 Risk Analysis White Paper'' for 
2011-NE-42-AD that we uploaded to the AD docket on June 23, 2015. 
Therefore, we are requiring removal of affected cylinder assemblies 
from service prior to TBO. We did not change this proposed AD.

FAA's Determination

    We are proposing this SNPRM to allow the public the opportunity to 
comment on additional information we added to the docket of this 
proposed rule.

Proposed Requirements of this SNPRM

    As proposed in the first SNPRM published on January 8, 2015 (80 FR 
1008), this second SNPRM would require removal of the affected cylinder 
assemblies, including overhauled cylinder assemblies, according to a 
phased removal schedule.

Costs of Compliance

    We estimate that this proposed AD would affect about 5,000 CMI 
models IO-520, TSIO-520, IO-550, and IOF-550 reciprocating engines and 
all other CMI engine models approved for the use of CMI models 520 and 
550 cylinder assemblies (such as the CMI model 470 when modified by 
STC), installed on airplanes of U.S. registry. The average labor rate 
is $85 per hour. We estimate that about 18 hours would be required to 
replace all six cylinder assemblies during overhaul maintenance. We 
estimate the pro-rated value of the cost of replacement of six cylinder 
assemblies to be about $4,202 per engine. Based on these figures, we 
estimate the total cost of this proposed AD to U.S. operators to change 
all ECi cylinder assemblies to be $28,660,000. Our cost estimate is 
exclusive of possible warranty coverage.

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.
    We are 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

    We determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would not 
have a substantial direct effect on the States, on the relationship 
between the national Government and the States, or on the distribution 
of power and responsibilities among the various levels of government.
    For the reasons discussed above, I certify this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979),
    (3) Will not affect intrastate aviation in Alaska to the extent 
that it justifies making a regulatory distinction, and
    (4) 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 
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

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 (AD):

Continental Motors, Inc. (formerly Teledyne Continental Motors, 
Inc., formerly Continental): Docket No. FAA-2012-0002; Directorate 
Identifier 2011-NE-42-AD.

(a) Comments Due Date

    We must receive comments by September 28, 2015.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all Continental Motors, Inc. (CMI) model 520 
and 550 reciprocating engines, and to all other CMI engine models 
approved for the use of model 520 and 550 cylinder assemblies such 
as the CMI model 470 when modified by supplemental type certificate 
(STC), with Airmotive Engineering Corp. replacement parts 
manufacturer approval (PMA) cylinder assemblies, marketed by Engine 
Components International Division (hereinafter referred to as ECi), 
part number (P/N) AEC631397, with ECi Class 71 or Class 76, serial 
number (S/N) 1 through S/N 61176, installed.

(d) Unsafe Condition

    This AD was prompted by multiple failure reports of cylinder 
head-to-barrel separations and cracked and leaking aluminum cylinder 
heads. We are issuing this AD to prevent failure of the cylinder 
assemblies, which could lead to failure of the engine, in-flight 
shutdown, and loss of control of the airplane.

(e) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.
    (1) Review the engine maintenance records to determine if any 
affected cylinder assemblies are installed.
    (2) If you cannot determine based on review of engine 
maintenance records if any affected cylinder assemblies are 
installed, comply with paragraph (e)(4) of this AD.

[[Page 52215]]

    (3) If you do not have any of the affected ECi cylinder 
assemblies installed on your engine, no further action is required.

(4) Cylinder Identification and Serial Number Location

    (i) Check the cylinder assembly P/N and Class number. The ECi 
cylinder assembly, P/N AEC631397, Class 71 or Class 76, is stamped 
on the bottom flange of the cylinder barrel. Guidance on the P/N and 
Class number description and location can be found in ECi Service 
Instruction No. 99-8-1, Revision 9, dated February 23, 2009.
    (ii) If you cannot see the cylinder assembly P/N when the 
cylinder assembly is installed on the engine, you may use the 
following alternative method of identification:
    (A) Remove the cylinder assembly rocker box cover.
    (B) Find the letters ECi, cast into the cylinder head between 
the valve stems.
    (C) Check the cylinder head casting P/N. Affected cylinder 
assemblies have the cylinder head casting P/N, AEC65385, cast into 
the cylinder head between the valve stems.
    (D) Find the cylinder assembly S/N as specified in paragraph 
(e)(4)(iii) or (e)(4)(iv) of this AD, as applicable.
    (iii) For ECi cylinder assemblies, P/N AEC631397, manufactured 
through 2008, find the cylinder assembly S/N stamped on the intake 
port boss two inches down from the top edge of the head.
    (iv) For ECi cylinder assemblies, P/N AEC631397, manufactured on 
or after January 1, 2009, find the cylinder assembly S/N stamped 
just below the top edge of the head on the exhaust port side.

(5) Removal From Service

    (i) For any affected cylinder assembly with 680 or fewer 
operating hours time-in-service (TIS) since new on the effective 
date of this AD, remove the cylinder assembly from service before 
reaching 1,000 operating hours TIS since new.
    (ii) For any affected cylinder assembly with more than 680 
operating hours TIS since new and 1,000 or fewer operating hours TIS 
since new on the effective date of this AD, remove the cylinder 
assembly from service within the next 320 operating hours TIS or 
within 1,160 operating hours TIS since new, whichever occurs first.
    (iii) For any affected cylinder assembly with more than 1,000 
operating hours TIS since new on the effective date of this AD, 
remove the cylinder assembly from service within the next 160 
operating hours or at next engine overhaul, whichever occurs first.
    (iv) For any affected cylinder assembly that has been 
overhauled, remove the cylinder assembly from service within the 
next 80 operating hours TIS after the effective date of this AD.

(f) Installation Prohibitions

    After the effective date of this AD:
    (1) Do not repair, or reinstall onto any engine, any cylinder 
assembly removed per this AD.
    (2) Do not install any affected ECi cylinder assembly that has 
been overhauled, into any engine.
    (3) Do not install any engine that has one or more affected 
overhauled ECi cylinder assemblies, onto any aircraft.
    (4) Do not return to service any aircraft that has an engine 
installed with an ECi cylinder assembly subject to this AD, if the 
cylinder assembly has 1,000 or more operating hours TIS.

(g) Alternative Methods of Compliance (AMOCs)

    The Manager, Delegation Systems Certification Office, may 
approve AMOCs for this AD. Use the procedures found in 14 CFR 39.19 
to make your request.

(h) Related Information

    (1) For more information about this AD, contact Jurgen E. 
Priester, Aerospace Engineer, Delegation Systems Certification 
Office, FAA, Rotorcraft Directorate, 2601 Meacham Blvd., Fort Worth, 
TX 76193; phone: 817-222-5190; fax: 817-222-5785; email: 
[email protected].
    (2) For ECi Service Instruction No. 99-8-1, Revision 9, dated 
February 23, 2009, contact Engine Components International Division, 
9503 Middlex Drive, San Antonio, TX 78217; phone: 210-820-8101; 
Internet: http://www.eci.aero/pages/tech_svcpubs.aspx.
    (3) You may view this service information at the FAA, Engine & 
Propeller Directorate, 12 New England Executive Park, Burlington, 
MA. For information on the availability of this material at the FAA, 
call 781-238-7125.

    Issued in Burlington, Massachusetts, on August 10, 2015.
Colleen M. D'Alessandro,
Directorate Manager, Engine & Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 2015-21205 Filed 8-27-15; 8:45 am]
 BILLING CODE 4910-13-P


Current View
CategoryRegulatory Information
CollectionFederal Register
sudoc ClassAE 2.7:
GS 4.107:
AE 2.106:
PublisherOffice of the Federal Register, National Archives and Records Administration
SectionProposed Rules
ActionSupplemental notice of proposed rulemaking (NPRM); reopening of comment period.
DatesWe must receive comments on this SNPRM by September 28, 2015.
ContactJurgen E. Priester, Aerospace Engineer, Delegation Systems Certification Office, FAA, Rotorcraft Directorate, 2601 Meacham Blvd., Fort Worth, TX 76137; phone: 817-222- 5190; fax: 817-222-5785; email: [email protected]
FR Citation80 FR 52212 
RIN Number2120-AA64
CFR AssociatedAir Transportation; Aircraft; Aviation Safety; Incorporation by Reference and Safety

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