What exactly is a SORA risk analysis, and how can it help you create an Operating Manual for your drone operation in the Specific Category?

JARUS (the Joint Authorities for Rulemaking on Unmanned Systems) developed the Specific Operations Risk Assessment (SORA) to provide drone operators with a methodology for the risk assessment required to apply for an authorisation to operate an Unmanned Aircraft System within the specific category.

The SORA propose risk barriers to keep the operation from getting out of control, as well as harm barriers in the event that it does (e.g. an emergency response plan). The SORA procedure begins with the operator defining an operational volume in which the drone operation will take place. This operational volume is related to adjacent airspace as well as the surrounding ground area. A Ground Risk Model (GRC) and an Air Risk Model (ARC) are included in the SORA to determine risks to the surrounding area and adjacent airspace, as well as to propose mitigation steps to reduce those risks.

In this article, we’ll go through the SORA methodology and how it may assist you in creating an Operating Manual for your drone operation.

The Concept of Operations (ConOps)

The Concept of Operations or ConOps for the drone operation you intend to carry out is the first step in the SORA process. This ConOps requires you to collect and submit enough technical, operational, and human information related to the UAS’s intended use. The ConOps should not only describe your operation but also provide insight into the organisation’s operational safety culture.

Basically, you’ll need to describe the who, what, and where of the operation you’re going to perform. You’ll need information regarding the drone and supporting equipment that will be used, as well as who will pilot the drone (and what qualifications he or she has), how the organisation will ensure that the operation is carried out safely, and where the operation will take place (e.g. the airspace classification and the area that will be overflown).

Determining the Ground Risk Class (GRC)

The unmitigated risk of a person being struck by a drone (in the event of a loss of control) is indicated by Ground Risk Classes (GRC) in the SORA. The initial GRC is derived solely based on the drone’s size and kinetic energy, the kind of operation (VLOS or BVLOS), and the operational scenario (operations over an unpopulated or populated area, if the area is controlled or if the area includes a gathering of people).

Mitigations can be used to control and reduce the unmitigated risk of a person being struck by a UAS. This can be achieved, for example, by having an efficient Emergency Response Plan (ERP). The GRC can also be reduced by minimising the effect of the drone’s ground impact by fitting an emergency parachute. The use of effective technical containment is a third option (e.g. active geofencing).

Each risk mitigation gives you a factor (+1 to -4) that you can apply to the initial GRC to get the final Ground Risk Class. After determining the final GRC, the following stage is to assess the operation’s air risks.

Determining the Air Risk Class (ARC)

The Air Risk Class (ARC) is a qualitative classification of the likelihood of a drone encounter with a manned aircraft in typical civil airspace. It gives an initial indication of the collision risk in the airspace before mitigations are implemented. The ARC can be found by answering questions in the SORA flow chart concerning the operation’s altitude, whether it’s in controlled or uncontrolled airspace, whether it’s near an airport, and whether it’s overflying urban or rural areas.

The flow chart will show you what the initial ARC (a – d) for the operation is. However, because the ARC is a broad classification, you – the operator – could consider that the qualification is too high for the conditions in the intended operational volume. If this is the case, strategic and tactical mitigations can be used to lower the ARC.

Procedures and operational restrictions targeted at lowering the drone’s encounter rate, or time of exposure, prior to take-off are commonly referred to as strategic mitigation. There are two types of strategic mitigations: those that can be controlled by the operator (strategic mitigation by operational restrictions) and those that cannot (strategic mitigation by structures and rules).

Tactical mitigation, often known as “mitigating feedback loops,” is a type of mitigation that is implemented after takeoff. A mitigating feedback loop is a dynamic system that uses updated aircraft conflict information such as air traffic control (ATC) traffic alert and collision avoidance system (TCAS), unmanned traffic management (UTM), and “See and Avoid” to lower the rate of collision (VLOS).

The final ARC can be determined when the strategic and tactical mitigations have been applied. ARC objectives can be formed based on the final ARC results to prevent an infringement of adjacent airspace next to the operational volume. The final ARC, in combination with the final GRC, will determine the Specific Assurance and Integrity Levels (SAIL), which will form the Operational Safety Objectives (OSO).

What are SAIL and OSO?

Specific Assurance and Integrity Levels (SAIL) are the SORA methodology’s chosen parameter for combining ground and air risk analysis. The level of confidence represented by the SAIL is not quantitative but instead corresponds to objectives that must be met, descriptions of activities that may support meeting objectives, and evidence that the objectives have been satisfied.

Operational Safety Objectives (OSO) are established based on the SAIL (levels I – VI) for barriers and mitigations to various threats, such as a technical issue with the UAS, deterioration of external supporting systems, human error, and poor operating conditions. The requirements for the operator’s organisation, the drone, and the pilot are all outlined in these OSOs.

For the pilot, he will be required to meet certain knowledge and skill levels. The right theoretical and practical drone training can help you achieve these goals. The OSO also describes the standards for the technical assessment of the drone, equipment, and service. Having the right drone and equipment is critical for conducting a safe operation. The organisation itself requires a SORA-compliant Operating Manual in order to have the right procedures in place to conduct drone operations safely and efficiently.

Writing a SORA compliant Operating Manual

In order to set up a safe and efficient drone operation, you’ll need a professional Operating Manual. We’ve developed Operating Manuals for a variety of organisations in a variety of industries. And, while each organisation and drone operation is unique, we’ve identified a few must-haves for a SORA-compliant Operating Manual.

The first step is to ensure that your manual is properly organised, with general information clearly separated from operating procedures and other sections. For this, we at Aerofleye adopt a format derived from traditional aviation manuals. It’s also crucial to clarify the organisation behind your flight operation, as well as the roles that have been assigned. A third criterion is to provide sufficient technical information regarding the drones, equipment, and services that are employed in your operation, as well as any applicable maintenance requirements.

The procedures that your employees must follow will be at the heart of your operating manual. It’s vital to establish clear and simple standard operating procedures (SOPs) for all actions, from flight planning to post-flight data processing. All mitigating measures resulting from your SORA analysis must be implemented into your normal, abnormal, and emergency procedures.

The final need is to provide all documentation required for a mission to your personnel. Make sure that they have easy access to all checklists, forms, and other materials. This will save you a lot of time and money if you use a professional Drone Operations Management System.

At Aerofleye, we’ve helped organisations in various industries establish a safe, efficient, and compliant drone operation. Contact us to take advantage of our consultants’ experience, knowledge and expertise. Our experts will guide you on how to use the SORA risk analysis methodology and create a customised operating manual for your operation.