Posted: 24th August, 2026
As drone operations become more advanced, operators increasingly need to demonstrate that flights can be conducted safely within complex environments. This is particularly important for operations that go beyond the relatively low-risk activities permitted within the Open Category.
In the UK, the UK SORA methodology provides a structured way of assessing the risks associated with a proposed unmanned aircraft system (UAS) operation and identifying the measures required to manage those risks. For organisations developing advanced drone operations, understanding SORA is becoming an increasingly important part of planning, testing and obtaining the appropriate regulatory authorisation.
SORA stands for Specific Operations Risk Assessment. The methodology considers the risks associated with a proposed UAS operation, particularly the potential risk to people on the ground and other aircraft in the air. Rather than treating every drone operation in the same way, SORA provides a structured framework for assessing the characteristics and risks of a particular operation and identifying appropriate mitigations, technical requirements and operational procedures. For operations not covered by an available CAA Pre-Defined Risk Assessment (PDRA), UK SORA is the CAA’s standard route for applying for an Operational Authorisation in the Specific Category.
UK drone operations are divided into regulatory categories based on the level of risk involved. The Open Category covers many lower-risk drone operations that can be conducted within defined limits without an Operational Authorisation. More complex operations may fall within the Specific Category.
These can include activities such as Beyond Visual Line of Sight (BVLOS) operations, flights outside the Open Category height limits, operations that do not meet Open Category separation requirements for uninvolved people or assemblies of people, and operations involving the dropping of material from an unmanned aircraft. Operators conducting activities within the Specific Category will generally require an Operational Authorisation from the Civil Aviation Authority (CAA).
Specific Operations Risk Assessment considers two principal areas of operational safety: ground risk and air risk. Ground Risk Class (GRC) considers the potential risk of the unmanned aircraft striking a person on the ground and causing a fatality. Air Risk Class (ARC) considers the potential for a mid-air collision between an unmanned aircraft and crewed aircraft. These assessments contribute towards determining the Specific Assurance and Integrity Level (SAIL) of the proposed operation. SAIL levels range from 1 to 6. Rather than being a simple risk rating, the SAIL determines the level of assurance, robustness and compliance evidence required for the operation. The resulting SAIL level helps determine the Operational Safety Objectives and other requirements that an operator will need to satisfy.
Another important consideration within UK SORA is the operational volume. This defines the three-dimensional area in which the drone operation is planned to take place and incorporates both the intended flight volume and a contingency volume. Operators must also consider a ground risk buffer and the adjacent area surrounding the operation. Understanding these areas is particularly important when developing more complex UAS operations, where careful flight planning and containment measures may be required.
SORA is particularly relevant to organisations developing Beyond Visual Line of Sight operations. A BVLOS operation is any operation that is not conducted in Visual Line of Sight. This includes situations where the remote pilot cannot maintain continuous unaided visual contact with the unmanned aircraft sufficient to control its flight path in relation to other aircraft, people and obstacles.
This creates significant opportunities for applications including infrastructure inspection, maritime operations, logistics, surveillance and emergency response. However, operating beyond visual line of sight introduces additional considerations around airspace, communications, containment, operational procedures and collision risk. A structured risk assessment can therefore play an important role in demonstrating how these risks will be managed.
Developing a SORA is only part of preparing an advanced UAS operation. Organisations may also need to demonstrate that their aircraft, supporting systems and operational procedures perform as intended. Structured UAS testing can provide an opportunity to validate elements of a proposed operation within a professional aviation environment before progressing towards wider operational deployment. Testing can support the compliance evidence required for a UK SORA application, but it does not itself establish regulatory compliance or guarantee that the CAA will grant an Operational Authorisation.
Drone Certification Agency provides specialist facilities and operational support for organisations developing and testing advanced unmanned aircraft systems. Operating from Portland Heliport in Dorset, DCA provides access to a professional UAS testing environment at a CAA Pre-assessed Test Site, alongside flight test planning and support with SORA development. The combination of aviation infrastructure, operational expertise and access to suitable testing environments enables organisations to develop, evaluate and demonstrate UAS capabilities as they progress towards increasingly complex operations.
The UAS operator remains responsible for its application and operation, and the CAA remains responsible for assessing the application and deciding whether to grant an Operational Authorisation.
Whether you are developing a BVLOS operation, undertaking system integration or preparing a new UAS capability for operational deployment, Drone Certification Agency can support your testing and evaluation requirements.