ISO 24356:2022

INTERNATIONAL ISO
STANDARD 24356
First edition
2022-08
General requirements for tethered
unmanned aircraft systems
Exigences générales relatives aux aéronefs sans pilote captifs
Reference number
ISO 24356:2022(E)
© ISO 2022

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ISO 24356:2022(E)
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© ISO 2022
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Published in Switzerland
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ISO 24356:2022(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 2
5 System general requirements.2
5.1 General requirements . 2
5.2 Composition of tUAS . 3
5.3 Design for long-duration reliability . 3
6 Operator’s manual requirements . 3
6.1 System performance . 3
6.2 Weight limits . 4
6.3 Electrical characteristics . 4
6.4 Environmental characteristics . 4
6.5 Fatigue endurance and life characteristics . 5
6.6 Paintings and markings for tUAS safety . 5
6.7 Lighting . 5
6.8 Others . 5
7 Airborne monitoring system .5
7.1 System functions . 5
7.2 Monitoring software . 6
7.3 Wireless data transmission module . 6
8 Propulsion and electrical system .6
8.1 Propulsion system . 6
8.2 Electrical system . 7
8.2.1 General . 7
8.2.2 Airborne electrical system . 7
8.2.3 Ground electrical system . 8
9 Power transportation system . 8
9.1 Tethering cables . 8
9.2 Winches . 9
9.2.1 Characteristics . 9
9.2.2 Environment adaptability, protection and connectors . 9
9.2.3 Functional elements . 10
10 Remote pilot station .10
11 Test verification .10
11.1 General . 10
11.2 Test purposes . 11
11.3 Test contents. 11
Bibliography .12
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ISO 24356:2022(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
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any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
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World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/
iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 20, Aircraft and space vehicles,
Subcommittee SC 16, Unmanned aircraft systems.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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ISO 24356:2022(E)
Introduction
The purpose of this document is to describe a general technical architecture for tethered unmanned
aircraft systems (tUAS). It addresses the general requirements for components and subsystems,
functions and performance. The objective is to promote international trade, provide a technical basis
for related industrial applications, a guidance for development and manufacturing, and to promote safe
operations.
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INTERNATIONAL STANDARD ISO 24356:2022(E)
General requirements for tethered unmanned aircraft
systems
1 Scope
This document specifies general and manufacturing requirements for tethered unmanned aircraft
systems (tUAS), including heavier-than-air tethered unmanned aircraft (tUA), which are powered by
equipment on the ground. The specifications are intended for tUAS where the purpose for the tether is
to supply power to the tUA as well as to provide a mechanical restraint. Unmanned aircrafts (UAs) that
are not receiving power from and only restrained by the tether are referred to ISO 21384-2; however,
there are clauses in this document that apply to the tethering equipment (e.g. winches and cables).
This document is applicable to the development, manufacturing, industrial applications and delivery of
tUAS.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 21384-2, Unmanned aircraft systems — Part 2: UAS components
ISO 21384-4, Unmanned aircraft systems — Part 4: Vocabulary
ISO 23629 (all parts), UAS traffic management (UTM)
IEC 60228, Conductors of insulated cables
IEC 60811, Common test methods for insulating and sheathing materials of electric cables and optical
cables
IEC 60885-1, Electrical test methods for electric cables — Part 1: Electrical tests for cables, cords and wires
for voltages up to and including 450/750 V
IEC 61076-1, Connectors for electronic equipment — Product requirements — Part 1: Generic specification
IEC 61076-2, Connectors for electronic equipment — Product requirements — Part 2: Circular connectors
IEC 62133, Secondary cells and batteries containing alkaline or other non-acid electrolytes — Safety
requirements for portable sealed secondary cells, and for batteries made from them, for use in portable
applications
IEC 62197-1, Connectors for electronic equipment — Product requirements — Part 1: Generic specification
IEC 62197-2, Connectors for electronic equipment — Product requirements — Part 2: Sectional specification
for circular connectors
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 21384-2, ISO 21384-4 and the
following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
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ISO 24356:2022(E)
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
winch
ground device which is able to automatically or manually coil and uncoil the cables
3.2
heavier-than-air tethered unmanned aircraft
heavier-than-air tUA
tUA (3.5), with a take-off weight that is more than the air it displaces
3.3
uninterruptible power supply
UPS
power supply system that provides emergency power to the unmanned aircraft system when the main
power supply is disrupted
3.4
tethering cable
cable that provides power and a mechanical constraint to an unmanned aircraft, and may also be able
to exchange data with the unmanned aircraft
3.5
tethered unmanned aircraft
tUA
unmanned aircraft with range of movement limited by a tethering cable (3.4) and electrical power
supplied by ground equipment conveyed through the tethering cable
3.6
tethered unmanned aircraft system
tUAS
UAS comprised of a tUA (3.5) and associated components (e.g. tethering cable (3.4), winches (3.1),
ground-based electrical system and with a potential for data exchange)
4 Abbreviated terms
GNSS global navigation satellite system
RPS remote pilot station
tUA tethered unmanned aircraft
tUAS tethered unmanned aircraft system
UA unmanned aircraft
UPS uninterruptible power supply
UTM UAS traffic management
5 System general requirements
5.1 General requirements
General requirements for the tUAS shall be consistent with the general requirements for multirotor UAS
given in ISO 21384-2, including but not limited to requirements for avionics, propulsion, navigation,
flight control system, command and control link, RPS and mission payload interface. Additional
requirements are specified in this document.
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ISO 24356:2022(E)
5.2 Composition of tUAS
A system shall be considered as a tUAS when consisting of a minimum of the following components:
a) tUA, including the airframe, avionics, propulsion, and electrical, navigation and flight control
systems;
b
...