ISO 14620-3:2021

Overview

ISO 14620-3:2021 - Space systems - Safety requirements - Part 3: Flight safety systems - defines minimum international requirements for flight safety systems (FSSs) used in commercial and non‑commercial launches of orbital or suborbital, unmanned space vehicles. The standard covers flight termination systems (FTSs) (externally controlled or onboard automatic), range tracking systems (RTS), and telemetry data transmitting systems (TDTSs). Its primary intent is to minimize risk of injury, property damage and environmental harm from launch activities and to provide a common safety baseline for operators, launch authorities and range organizations.

Key topics and technical requirements

• Scope & applicability

  • Applies to orbital and suborbital, unmanned launch activities unless overridden by more restrictive launch‑site rules.
  • Can be adopted by countries, international organizations, agencies, operators and launch authorities.

• Flight safety system (FSS) fundamentals

  • FSS comprises flight-, ground- or space‑based hardware and software for monitoring and protecting people and property.
  • FSS may include FTS, RTS and TDTS.

• Tracking and telemetry

  • All launch vehicles and spent stages (unless risk demonstrated otherwise) must include tracking devices or means for real‑time position/velocity monitoring and instantaneous impact point prediction.
  • TDTS must downlink vehicle performance, FTS and tracking status and function through the end of range safety responsibility.

• Flight termination system (FTS) requirements

  • FTS required when a vehicle or stage can violate the defined safety envelope.
  • FTS flight equipment reliability ≥ 0.999, or must conform to quantitative requirements in ISO 14620‑2 if stricter.
  • Systems must eliminate single failure points (SFPs) that could inhibit or spur undesired outputs; verify via SFP analysis.
  • Termination action must render propulsive systems non‑propulsive; specific measures for liquid and solid propellants (e.g., engine shutdown, destruct charges to destroy pressure integrity).
  • Redundancy for active components, cables, batteries and ordnance; physical separation of redundant lines where feasible.
  • External FTS: antenna/receiver/decoder compatibility with ground support equipment (GSE); RF path assurance; antenna coverage >95% of the radiation sphere; response time sufficient to maintain the safety envelope.
  • Safe and arm (S&A) devices: interlocks, fault tolerance, pre‑launch testing, means to remotely interrupt initiation energy.

• Operational controls

  • Loss of accurate vehicle position normally requires FTS initiation or mission/range rules to specify otherwise.
  • Inability to ascertain position should stop launch countdown.
  • Radioactive payloads must meet applicable regulatory compliance.

Applications - who uses this standard

• Launch vehicle designers and systems engineers (FTS, telemetry and tracking design)
• Launch operators and vehicle integrators (pre‑flight checks, mission rules)
• Range operators, spaceports and ground support equipment (GSE) providers (compatibility and coverage)
• Safety engineers, regulators and certification bodies (risk analysis, SFP analysis, reliability demonstration)
• Insurance underwriters and compliance officers assessing launch safety measures

Related standards

• ISO 14620‑1 - System safety (safety analysis, overall principles)
• ISO 14620‑2 - Launch site operations (quantitative flight safety requirements)
• ISO 10795 - Space systems vocabulary (terms and definitions)

ISO 14620-3:2021 provides a practical, safety‑focused framework for FSS design, verification and operations that supports consistent, internationally harmonized launch safety practices. Keywords: ISO 14620-3:2021, flight safety systems, flight termination system, telemetry, range tracking, launch vehicle safety.