ASTM F3316/F3316M-19

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Designation: F3316/F3316M − 18 F3316/F3316M − 19
Standard Specification for
Electrical Systems for Aircraft with Electric or Hybrid-
Electric Propulsion
This standard is issued under the fixed designation F3316/F3316M; 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
1.1 This specification covers the electrical systems, electrical equipment, and electrical power distribution aspects of
airworthiness and design for aircraft with Electric or Hybrid-Electric Propulsion. This specification was written with the focus on
electric propulsion systems with conventional system layout, characteristics, and operation. This specification does not address all
of the requirements that may be necessary for possible hybrid-electric configurations where an EPU and a combustion engine are
used in combination to provide propulsion. The use of this specification combined with the applicable portions of Specification
F3231/F3231M may be necessary for hybrid-electric configurations. This material was developed through open consensus of
international experts in general aviation. This material was created by focusing on Normal Category Airplanes.Aeroplanes. The
content may be more broadly applicable; it is the responsibility of the applicant to substantiate broader applicability as a specific
means of compliance.
1.2 An applicant intending to propose this information as a means of compliance for design approval mustshall seek guidance
from their respective oversight authority (for example, published guidance from applicable CAAs) concerning the acceptable use
and application thereof. For information on which oversight authorities have accepted this standard (in whole or in part) as a Means
of Compliance to their regulatory requirements (Hereinafter referred to as “the Rules”), refer to ASTM F44 webpage
(www.ASTM.org/COMMITTEE/F44.htm).
1.3 Units—This standard may present information in either SI units, English Engineering units, or both; theboth. The values
stated in each system mayare not be exact equivalents. Each necessarily exact equivalents; therefore, to ensure conformance with
the standard, each system shall be used independently of the other; combiningother, and values from the two systems may result
in nonconformance with the standard.shall not be combined.
1.4 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, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
F2490 – 05 Standard Guide for Aircraft Electrical Load and Power Source Capacity Analysis
F2639 Practice for Design, Alteration, and Certification of Aircraft Electrical Wiring Systems
F3060 Terminology for Aircraft
F3061/F3061M Specification for Systems and Equipment in Small Aircraft
F3066/F3066M Specification for Aircraft Powerplant Installation Hazard Mitigation
F3231/F3231M Specification for Electrical Systems for Aircraft with Combustion Engine Electrical Power Generation
F3235 Specification for Aircraft Storage Batteries
F3239 Specification for Aircraft Electric Propulsion Systems
This specification is under the jurisdiction of ASTM Committee F44 on General Aviation Aircraft and is the direct responsibility of Subcommittee F44.50 on Systems
and Equipment.
Current edition approved May 15, 2018Nov. 1, 2019. Published June 2018December. Originally approved in 2018. Last previous edition approved in 2019 as
F3316/F3316M–19. DOI: 10.1520/F3316_F3316M-18.10.1520/F3316_F3316M–19.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’sstandard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F3316/F3316M − 19
F3338 Specification for Design of Electric Propulsion Units for General Aviation Aircraft
2.2 FAA Standard:
DOT/FAA/AR-00/12 Aircraft Materials Fire Test Handbook
3. Terminology
3.1 Terminology specific to this specification is provided below. For general terminology, refer to Terminology F3060.
Available from Federal Aviation Administration (FAA), 800 Independence Ave., SW, Washington, DC 20591, http://www.faa.gov.
F3316/F3316M − 19
3.2 Definitions of Terms Specific to This Standard:
3.2.1 aircraft type code, n—an Aircraft Type Code (ATC) is defined by considering both the technical considerations regarding
the design of the aircraft and the airworthiness level established based upon risk-based criteria; the method of defining an ATC
applicable to this specification is defined in Specification F3061/F3061M.
3.2.2 continued safe flight and landing, n—continued safe flight and landing as applicable to this specification is defined in
Specification F3061/F3061M.
3.2.3 Battery Management System (BMS)—a battery management system is any electronic system that manages a rechargeable
battery (cell or battery pack), such as by protecting the battery from operating outside its Safe Operating Area, monitoring its state,
calculating secondary data, reporting that data, controlling its environment, authenticating it or balancing it, or both.
3.2.4 Electric Propulsion System (EPS)—installation that includes at least one EPU and hardware required to produce
propulsive thrust. Multiple EPUs may be in different arrangements such as serial or parallel or a combination of the two.
3.2.4 Electric Propulsion Unit (EPU)—the EPU shall as a minimum consist EPU is comprised of the electric motor, associated
controllers disconnects and wiring, motor generator, and monitoring gauges and meters.electronic controllers, disconnects, wiring,
and sensors.
3.2.4.1 Discussion—
See Specification F3338 for additional information.
3.2.5 Energy Storage System (ESS)—any manner that stores some form of a source (component or system) that stores and
provides energy that can be drawn upon at a later time to provide energy for propulsion. Typical energy storage devices include
but are not limited to: batteries, fuel cells, or capacitors.for propulsion.
3.2.5.1 Discussion—
See Specification F3239 for additional information.
3.3 Abbreviations:
3.3.1 BMS—Battery Management System
3.3.2 EPS—Electric Propulsion System
3.3.3 EPU—Electric Propulsion Unit
3.3.4 ESS—Energy Storage System
4. Electrical Systems for Electric Propulsion
NOTE 1—Table 1 provides correlation between various Aircraft Type Codes and the individual requirements contained within this section; refer to 3.2.1.
For each subsection, an indicator can be found under each ATC character field; three indicators are used:
An empty cell ( ) in all applicable ATC character field columns indicates that an aircraft mustshall meet the requirements of that subsection.
A white circle (○) in multiple columns indicates that the requirements of that subsection are not applicable to an aircraft only if all such ATC character
fields are applicable.
A mark-out (×) in any of the applicable ATC character field columns indicates that the requirements of that subsection are not applicable to an aircraft
if that ATC character field is applicable.
Example—An aircraft with an ATC of 1SRLLDLN is being considered. Since all applicable columns are empty for 4.2.1, that subsection is applicable
to the aircraft. Since both the “L” stall speed column and the “D” meteorological column for 4.1.14.1.1.2 contain white circles, then that subsection is
not applicable; however, for an aircraft with an ATC of 1SRMLDLN, 4.1.14.1.1.2 would be applicable since the “M” stall speed column does not contain
a white circle.
4.1 Power Source Capacity and Distribution:
4.1.1 Each installation whose functioning is required for type certification or under operating rules and that requires a power
supply is an “essential load” on the power supply. The power sources and the system mustshall be able to supply the power loads
specified in 4.1.1.1 – 4.1.1.3 in probable operating combinations and for probable durations. The power loads may be assumed to
be reduced under a monitoring procedure consistent with safety in the kinds of operation authorized.
4.1.1.1 The power sources and the electrical distribution system, when functioning normally, mustshall be able to support all
connected loads.
4.1.1.2 The power sources and the electrical distribution system mustshall be able to support all essential loads after the failure
of any one ESS or primary electrical power source. An EPU designed to be connected to only one ESS is excluded from this
requirement.
4.1.1.3 The power sources and the electrical distribution system mustshall be able to support all essential loads for which an
alternate source of power is required, after any failure or malfunction in any one ESS, any one power supply system, any one
distribution system, or any other utilization system. An EPU designed to be connected to only one ESS is excluded from this
requirement.
F3316/F3316M − 19
TABLE 1 ATC Compliance Matrix, Section 4
Number of Type of Meteorological
Certification Level Stall Speed Cruise Speed Altitude Maneuvers
Section Engines Engine(s) Conditions
1 2 3 4 S M R T L M H L H D N I L H N A
4.1
4.1.1 C C
4.1.1
4.1.1.1 C C
4.1.1.1
4.1.1.2 C C C
4.1.1.3 C C C
4.1.2 C C
4.1.2
4.1.2.1 C C
4.1.2.1
4.1.2.2 C C C ×
4.1.2.3 C C C ×
4.1.3 C C
4.1.3
4.2
4.2.1
4.2.2
4.2.3
4.2.4
4.2.5
4.2.6
4.2.7
4.2.8
4.2.9
4.2.10
4.2.11
4.2.12
4.2.13
4.2.14
4.2.15
4.2.16
4.2.15.1
4.2.15.2
4.2.15.3
4.2.17
4.2.16
4.3
4.3.1
4.3.2
4.3.3
4.3.4
4.3.5
4.4
4.4.1
4.4.2
4.4.1.1
4.4.1.2
4.4.3
4.4.2
4.5
4.5.1
4.5.2
4.6
4.6.1
4.6.2
4.6.3
4.6.4
4.6.5
4.6.6
4.6.7
4.6.8
4.7
4.7.1
4.7.2
4.7.3
4.8
4.8.1
4.8.2
4.9
4.9.1
4.9.2
F3316/F3316M − 19
4.9.3
4.9.4
4.9.5
4.9.6
4.9.7
4.9.8
4.9.9
4.1.2 The power source and the electrical distribution system used to satisfy the probable duration requirement of 4.1.1 is
required to provide electrical power to those loads that are essential to continued safe flight and landing including non-continuous
essential loads with enough capacity to meet the requirements of either 4.1.2.1, 4.1.2.2, or 4.1.2.3 as appropriate per Table 1.
4.1.2.1 The time needed to complete the function required, for continued safe flight and landing.
4.1.2.2 A time period of at least 30 minutes which includes the time to recognize the loss of primary power and to take
appropriate load shedding action.
4.1.2.3 A time period of at least 60 minutes which includes the time to recognize the loss of primary power and to take
appropriate load shedding action.
4.1.3 The electrical capacity duration requirement of 4.1.2 shall be demonstrated by test or analysis including all loads essential
tofor continued safe flight.flight and landing.
4.2 Electrical Systems and Equipment:
4.2.1 Electric power sources, their transmission cables, and their associated control and protective devices, mustshall be able
to furnish the required power at the proper voltage and frequency, if applicable to each load circuit essential for safe operation and
maintained within the limits for which the equipment is designed during any probable operating conditions.
4.2.2 Compliance with 4.2.1 mustshall be shown by an electrical load analysis or by electrical measurements that account for
the electrical loads applied to the electrical system in probable combinations and for probable durations.
NOTE 2—Guide F2490 provides information and methodology for an electrical load analysis.
4.2.3 Each electrical system, when installed, mustshall be free from hazards in itself, in its method of operation, and in its effects
on other parts of the aeroplane.
4.2.4 Each electrical system, when installed, mustshall be protected from fuel, oil, water, other detrimental substances, and
mechanical damage.
4.2.5 Each electrical system, when installed, mustshall be designed so that the risk of electrical shock to crew, passengers, and
ground personnel is reduced to a minimum.
4.2.6 Electric power sources mustshall function properly when connected in combination or independently.
4.2.7 No failure or malfunction of any electric power source may impair the ability of any remaining source to supply load
circuits essential for safe operation.
4.2.8 Each electrical system mustshall be designed so that essential load circuits can be supplied in the event of reasonably
probable faults or open circuits including faults in heavy current carrying cables.
4.2.9 A means mustshall be accessible in flight to the appropriate flight crewmembers for the individual and rapid disconnection
of the electrical power sources from the distribution system which includes the distribution busses, their associated feeders, each
control device, and each protective device.
4.2.10 If any particular system or item of equipment requires two independent sources of electrical power, their electrical energy
supply mustshall be ensured by means such as duplicate electrical equipment, throw over switching, or by the use of multichannel
or loop circuits separately routed.
4.2.11 There mustshall be a means to give immediate warning to the appropriate flight crew members of a failure of any primary
electrical power source.
4.2.12 Each electrical power source mustshall have a means to prevent damage to the electrical system, or to equipment supplied
by the electrical system that could result if the power source provided electrical power outside the qualified limits that would
damage the electrical system or equipment.
4.2.13 A means mustshall exist to indicate to appropriate flight crewmembers the electric power system quantities essential for
safe operation.
4.2.14 If provisions are made for connecting external power to the aeroplane, a means mustshall be provided to ensure that no
external power supply having an over voltage, an under voltage, a reverse polarity, or a reverse phase sequence, can supply power
to the aeroplane electrical system.
F3316/F3316M − 19
4.2.15 If provisions are made for connecting external power to the aeroplane, the external power connection must be located
so that its use will minimize the hazard to the aeroplane and ground personnel.
4.2.15 If provisions are made for connecting external power to the aeroplane to charge the aeroplane battery, a means must be
provided to automatically disconnect the external power in the event of aaeroplane, the external power connection shall meet the
requirements of 4.2.15.1 malfunctionthrough 4.2.15.3of the aeroplane battery or battery management system.
4.2.15.1 The external power connection shall be located so that its use will minimize the hazard to the aeroplane.
4.2.15.2 The external power connection shall be located so that its use will minimize the hazard to ground personnel.
4.2.15.3 If the external power connection is utilized to charge the aeroplane battery, a means shall be provided to automatically
disconnect the external power in the event of a malfunction of the aeroplane battery or battery management system.
4.2.16 If equipped with a combustion engine that is part of the Hybrid-Electric Propulsion System, electrical equipment
mustshall be so designed and installed such that in the event of a fire in the combustion engine compartment, during which the
surface of the firewall adjacent to the fire is heated to 1095°C [2000°F]1095 °C [2000 °F] for five minutes or to a lesser temperature
substantiated by the applicant, the equipment essential to continued safe operation and located behind the firewall on the opposite
side of the firewall from the combustion engine compartment will function satisfactorily and will not create an additional fire
...