SORA stands for Specific Operations Risk Assessment and its main goal is to determine the risk posed by drone operations. All drone operations which require a permit also require an application in accordance with the flight-specific SORA. This entails all flights above 120 metres, flights with drones exceeding the maximum take-off weight (MTOM) of 25 kg and all beyond visual line of sight (BVLOS) flights.

SORA consist of different documents and guidelines, which help to determine the risks associated with the drone flight and what measures will be taken to mitigate them. SORA sorts all possible risks connected with the flights into to classes: ground risk class (GRC) and air risk class (ARC). Based on the confidence of successful and controlled drone flight, the risk classes are then represented by Specific Assurance and Integrity Levels or SAIL. SAIL can be reduced by different threat barriers and mitigating measures.

What is needed for a successful SORA?

A successful SORA consists of:

• Concept of Operations (ConOps)
  Consisting of technical, operational and system information needed to assess the risk associated with the intended operation, ConOps describes the flight and how it will be carried out.
• Ground Risk Class (GRC) determination
  Ground Risk Class shows the risk of a person being struck by a drone during the operation. GRC value is dependent on the used size, speed and flight type of the drone (VLOS or BVLOS) and the operational scenario, flight area and if any population will be present in it. Mitigations such as Emergency Response Plan (ERP), an emergency parachute being installed or active geofencing can reduce the GRC.
• Air Risk Class (ARC) determination
  ARC shows the likelihood of the drone encountering a manned aircraft in the operations airspace. ARC depends on if the flight takes place in controlled or uncontrolled airspace, whether it’s near an airport, and whether it’s overflying urban or rural areas. Strategic or tactical mitigation can be implemented to lower the ARC. Strategic mitigation lowers the drone’s encounter rate or time of exposure prior to take-off through procedures and operational restrictions. Tactical mitigation consists of procedures undertaken after takeoff by the drone team. Tactical mitigation uses air traffic control (ATC) traffic alert and collision avoidance system (TCAS) and unmanned traffic management (UTM) to lower the rate of collision. ARC is determined when the strategic and tactical mitigations have been applied.
• Specific Assurance and Integrity Level (SAIL) determination
  SAIL combines ground and air risk analysis and gives the flight operation a level of confidence, ranging between 1 and 6. The levels themselves give an overview of objectives that must be met and activities that may support meeting those objectives.
• Operational Safety Objectives (OSO)
  OSO are based on the SAIL levels and list requirements for the drone, its operator and their organisation. Depending on the SAIL level, OSO might require the drone operator to meet certain knowledge and skill levels. OSO also describes the standards for the technical assessment of the drone, equipment, and service. For the organisation conducting drone flights, SORA-compliant Operating Manual has to be created to conduct drone operations safely and efficiently.

How Hepta can help you with your SORA

Having conducted hundreds, if not thousands of drone operations over multiple years, Hepta has both the knowledge and experience to successfully prepare all the needed SORA documentation, regardless of the location or operations goal. Be it BVLOS flights in difficult terrain or conducting operations in residential areas, we know from firsthand experience what is needed and how to achieve it.

Should you need help with creating SORA documents for your organisation, Hepta can help you. For additional information and enquires, feel free to contact Hepta’s SORA specialists