BVLOS Requirements for Drone Delivery in the UK: Operational Authorisation and Safety Case

Why BVLOS Is Essential for Drone Delivery

Drone delivery is fundamentally a BVLOS operation. Practical delivery routes extend far beyond the 500-metre visual line of sight limit that applies to standard Open Category operations. Whether delivering medical supplies to rural clinics, parcels to residential addresses, or food to customers, the drone must travel distances that make continuous visual observation by the remote pilot impractical or impossible.

Under CAP 722, BVLOS is not treated as a separate regulatory category. Instead, it is an operational capability that increases the risk level within the Specific Category framework. This elevated risk demands more rigorous mitigations and a more detailed safety case than equivalent visual line of sight operations.

Detect-and-Avoid (DAA) Technology

The most critical technical requirement for BVLOS delivery operations is a functioning detect-and-avoid system. In visual line of sight flights, the remote pilot serves as the primary means of detecting and avoiding other aircraft and obstacles. When the drone is beyond visual range, technology must fulfil this role.

The CAA does not prescribe specific DAA technologies but evaluates them on a case-by-case basis. Systems that delivery operators commonly employ include:

• ADS-B receivers: Detecting cooperative traffic that broadcasts its position via ADS-B transponders
• Radar-based systems: Small onboard radar units capable of detecting non-cooperative aircraft and obstacles
• Optical sensors: Camera-based detection systems using machine learning to identify approaching aircraft
• Acoustic sensors: Microphone arrays that can detect approaching aircraft by sound
• Multi-sensor fusion: Combining multiple detection methods to reduce blind spots and improve reliability

The CAA assesses each DAA system against the specific operational environment. A system adequate for rural delivery routes may not satisfy the CAA for urban operations where traffic density and obstacle complexity are significantly higher.

Command and Control (C2) Link Requirements

A reliable command and control link between the ground control station and the delivery drone is non-negotiable for BVLOS operations. The CAA expects operators to demonstrate that the C2 link provides continuous two-way communication throughout the delivery route, redundancy through backup communication pathways, defined latency limits appropriate to the response time needed, automatic return-to-home or safe landing procedures if the C2 link is lost, and spectrum management compliance with Ofcom requirements.

For delivery operations covering significant distances, operators often use cellular network-based C2 links (4G/5G) as the primary communication pathway, with satellite links or dedicated radio frequencies as backup. The CAA will scrutinise coverage maps and link budget analyses for each planned delivery route.

Airspace Integration and Deconfliction

BVLOS delivery drones share airspace with manned aviation, and the CAA requires robust procedures to prevent conflicts. Key airspace considerations include proximity to controlled airspace (Class A through D) where permission from air traffic services is required, operations near aerodromes where drone flights are restricted, altitude management to minimise interaction with manned traffic, and coordination with NATS (National Air Traffic Services) for operations that may affect controlled airspace.

Electronic conspicuity — making the drone visible to other airspace users through electronic means — is increasingly expected for BVLOS delivery operations. This may involve transmitting ADS-B or equivalent position data so that manned aircraft and air traffic control can see the drone on their displays.

The BVLOS Safety Case

The SORA risk assessment for BVLOS delivery operations must address specific scenarios that do not arise in visual line of sight flights. These include complete loss of the C2 link during delivery, DAA system failure or degraded performance, unexpected weather changes along the delivery route that the pilot cannot directly observe, flyaway scenarios where the drone departs from the planned route, and emergency landing site identification along the entire route — not just near the takeoff point.

The CAA expects the safety case to quantify residual risk after all mitigations are applied. For delivery operations in populated areas, the residual risk of a fatal ground impact must be demonstrably low, typically expressed as a probability per flight hour.

CAA Innovation Team and Sandbox Trials

The CAA Innovation Team actively supports the development of BVLOS delivery capabilities. Through the Regulatory Sandbox programme, operators can conduct supervised BVLOS delivery trials that generate the operational data needed to support a full OA application. Wing (Alphabet) has used this pathway to conduct CAA-approved BVLOS delivery trials in the UK, demonstrating that the regulatory framework can accommodate routine delivery operations when properly evidenced.

Engaging with the Innovation Team before submitting a BVLOS application allows operators to receive feedback on their DAA approach, identify gaps in their safety case early, and potentially access the Sandbox programme for phased operational approval.