ISO 21895:2020

Overview

ISO 21895:2020 - Categorization and classification of civil unmanned aircraft systems - provides a multi-dimensional framework for classifying and grading civil UAS (unmanned aircraft systems). Applicable to both heavier‑than‑air and lighter‑than‑air architectures, the standard supports industrial activities across conception, design, production, delivery, modification, repair and maintenance. ISO 21895 is a technical tool for stakeholders who need more granular UAS classification than regulatory operational categories; note that risk‑based operational categorization remains the prerogative of aviation authorities and is out of scope.

Key topics and technical requirements

ISO 21895 defines structured classification axes and grading rules. Major topics include:

• UA‑configuration: fixed‑wing, glider, single‑rotor helicopter, multicopter, gyroplane, VTOL, aerostats, ornithopters and others.
• Launch and recovery / take‑off & landing modes: horizontal rollout, vertical, catapult/ejection, tether release, manual launch, parachute, net recovery, etc.
• Engine / powerplant and energy source: piston, turbine, electric, rocket, mixed powerplants; liquid, gaseous fuels, batteries, solar and hybrid energy sources.
• Control mode: manual (human in the loop), automatic (human on the loop), autonomous (human out of the loop); control mode can vary by flight phase.
• Performance levels:
  • Maximum achievable height (levels I–V from ≤15 m up to >18 300 m)
  • Maximum airspeed (levels defined in km/h and Mach ranges)
  • Flight endurance (from ≤0.5 h up to >24 h)
  • C2‑link coverage (operating radius categories up to >200 km)
  • Kinetic energy categories (levels I–V); kinetic energy calculated by the standard E = 1/2 m V^2 (with a specified equivalent multiplier for fixed‑wing V)
• Identification mode: unregistered, fixed label, electronic UAS ID, ATC transponder/ADS‑B capability.
• Grading by maximum take‑off mass: Levels I–VI (example ranges from ≤0.25 kg up to >150 kg).

Applications and who uses it

ISO 21895 is valuable for:

• Manufacturers and designers needing consistent classification for product development and compliance planning.
• Certification bodies and testing laboratories that require objective grading criteria for performance and safety assessment.
• Insurance underwriters and risk analysts to refine exposure models based on kinetic energy, mass and control modes.
• Accident investigators and maintenance organizations for post‑incident analysis and component grading.
• System integrators and procurement teams evaluating UAS variants by capability and operational envelope.

Keywords: ISO 21895, UAS classification, drone classification, unmanned aircraft systems, UAS grading, civil UAS standards, UAS certification.

Related standards

• Normative reference: ISO 21384‑4 (Unmanned aircraft systems - Part 4: Vocabulary) - used for terminology consistency.