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ASTM F2840-11

(Practice)

Standard Practice for Design and Manufacture of Electric Propulsion Units for Light Sport Aircraft

Standard Practice for Design and Manufacture of Electric Propulsion Units for Light Sport Aircraft

SIGNIFICANCE AND USE
This specification provides designers and manufacturers of electric propulsion for light sport aircraft design references and criteria to use in designing and manufacturing EPUs.
Declaration of compliance is based on testing and documentation during the design, ground testing and flight testing of the EPU by the manufacturer or under the manufacturers’ guidance.
Manufacturers of the EPUs are encouraged to review and incorporate appropriate standards and lessons learned from ground based systems as documented in SAE J2344 and EASA CRI F-58 (see Appendix X2).
Electric aircraft may contain potentially hazardous level of electrical voltage or current. It is important to protect persons from exposure to this hazard. Under normal operating conditions, adequate electrical isolation is achieved through physical separation means such as the use of insulated wire, enclosures, or other barriers to direct contact. There are conditions or events that can occur outside normal operation that can cause this protection to be degraded. Some means should be provided to detect degraded isolation or ground fault. In addition, processes or hardware, or both, should be provided to allow for controlled access to the high voltage system for maintenance or repair. A number of alternative means may be used to achieve these electrical safety goals including automatic hazardous voltage disconnects, manual disconnects, interlock systems, special tools and grounding. The intention of all these means is either to prevent inadvertent contact with hazardous voltages or to prevent damage or injury from the uncontrolled release of electric energy. Lightning strikes are not addressed in this Standard Practice because LSA aircraft are limited to VMC flight only.
SCOPE
1.1 This specification covers minimum requirements for the design and manufacture of Electric Propulsion Units (EPU) for light sport aircraft, VFR use. The EPU shall as a minimum consist of the electric motor, associated controllers, disconnects and wiring, an Energy Storage Device (ESD) such as a battery or capacitor, or both, and EPU monitoring gauges and meters. Optional onboard charging devices, in-flight charging devices or other technology may be included.
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

Status
Historical
Publication Date
28-Feb-2011
ICS
49.050 - Aerospace engines and propulsion systems
Technical Committee
F37 - Light Sport Aircraft
Drafting Committee
F37.20 - Airplane
Current Stage
Ref Project

Relations

Referred By
ASTM F2245-23 - Standard Specification for Design and Performance of a Light Sport Airplane
Effective Date
01-Mar-2011
Referred By
ASTM F3062/F3062M-20 - Standard Specification for Aircraft Powerplant Installation
Effective Date
01-Mar-2011
Referred By
ASTM F2564-14(2022) - Standard Specification for Design and Performance of a Light Sport Glider
Effective Date
01-Mar-2011

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ASTM F2840-11 - Standard Practice for Design and Manufacture of Electric Propulsion Units for Light Sport AircraftASTM F2840-11 - Standard Practice for Design and Manufacture of Electric Propulsion Units for Light Sport Aircraft
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ASTM F2840-11 - Standard Practice for Design and Manufacture of Electric Propulsion Units for Light Sport Aircraft
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: F2840 − 11
StandardPractice for
Design and Manufacture of Electric Propulsion Units for
1
Light Sport Aircraft
This standard is issued under the fixed designation F2840; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3.2 Declaration of compliance is based on testing and
documentation during the design, ground testing and flight
1.1 This specification covers minimum requirements for the
testing of the EPU by the manufacturer or under the manufac-
design and manufacture of Electric Propulsion Units (EPU) for
turers’ guidance.
light sport aircraft, VFR use. The EPU shall as a minimum
3.3 Manufacturers of the EPUs are encouraged to review
consist of the electric motor, associated controllers, discon-
andincorporateappropriatestandardsandlessonslearnedfrom
nects and wiring, an Energy Storage Device (ESD) such as a
groundbasedsystemsasdocumentedinSAEJ2344andEASA
battery or capacitor, or both, and EPU monitoring gauges and
CRI F-58 (see Appendix X2).
meters. Optional onboard charging devices, in-flight charging
devices or other technology may be included.
3.4 Electric aircraft may contain potentially hazardous level
of electrical voltage or current. It is important to protect
1.2 This standard does not purport to address all of the
persons from exposure to this hazard. Under normal operating
safety concerns, if any, associated with its use. It is the
conditions, adequate electrical isolation is achieved through
responsibility of the user of this standard to establish appro-
physical separation means such as the use of insulated wire,
priate safety and health practices and determine the applica-
enclosures, or other barriers to direct contact. There are
bility of regulatory limitations prior to use.
conditions or events that can occur outside normal operation
that can cause this protection to be degraded. Some means
2. Referenced Documents
shouldbeprovidedtodetectdegradedisolationorgroundfault.
2
2.1 ASTM Standards:
Inaddition,processesorhardware,orboth,shouldbeprovided
F2245 Specification for Design and Performance of a Light
to allow for controlled access to the high voltage system for
Sport Airplane
maintenance or repair. A number of alternative means may be
F2279 Practice for QualityAssurance in the Manufacture of
used to achieve these electrical safety goals including auto-
Fixed Wing Light Sport Aircraft
matic hazardous voltage disconnects, manual disconnects,
2.2 Other Standards:
interlocksystems,specialtoolsandgrounding.Theintentionof
3
EASA CRI F-58 Lithium Battery Installations
all these means is either to prevent inadvertent contact with
4
SAE J2344 Guidelines for Electric Vehicle Safety
hazardous voltages or to prevent damage or injury from the
uncontrolled release of electric energy. Lightning strikes are
3. Significance and Use not addressed in this Standard Practice because LSA aircraft
are limited to VMC flight only.
3.1 This specification provides designers and manufacturers
of electric propulsion for light sport aircraft design references
4. Electric Propulsion Unit (EPU) Model Designation
and criteria to use in designing and manufacturing EPUs.
4.1 Electric Propulsion Parts List—A detailed parts list is
required for each electric propulsion unit qualified in accor-
dance with this specification.
1
This practice is under the jurisdiction ofASTM Committee F37 on Light Sport
4.2 New Electric Propulsion Unit Model Designations:
Aircraft and is the direct responsibility of Subcommittee F37.20 on Airplane.
4.2.1 Each new EPU must be qualified in accordance with
Current edition approved March 1, 2011. Published April 2011. DOI: 10.1520/
F2840-11. this practice.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
4.2.2 Design or configuration changes that impact the in-
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
stallation interface, performance, or operability of the EPU
Standards volume information, refer to the standard’s Document Summary page on
require a new EPU model designation.
the ASTM website.
3
Available from EuropeanAviation SafetyAgency (EASA), Postfach 10 12 53,
4.3 Design Changes of Parts—Each design change of a part
D-50452 Koeln, Germany, http://easa.europa.eu/home.php.
4
or component of an EPU model qualified to this specification
Available from SAE International (SAE), 400 Commonwealth Dr.,Warrendale,
PA 15096-0001, http://www.sae.org. shall be evaluated to the requirements of this specification.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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