STS for Drone Operations
When to Choose an STS for Drone Operations
As a drone operator in the United Kingdom, it's essential to understand when using a Standard Scenario (STS) in the Specific Category is appropriate. An STS provides a standardized approach for certain drone operations, leading to a more efficient authorisation process and clearer operational guidelines.
What is a Standard Scenario (STS)?
A Standard Scenario (STS) is a predefined drone operation that meets strict requirements and conditions as set out in UK law, specifically under UK Regulation (EU) 2019/947 as retained and amended post-Brexit. The STS falls within the Specific Category framework and helps drone operators by standardising operational parameters, making the application for an operational authorisation more straightforward and efficient.
The STS concept was introduced to avoid the complexities of conducting a full risk assessment using methods like the Specific Operational Risk Assessment (SORA) when all prescribed conditions are fulfilled. This standardisation makes the process for UAS operators clearer, quicker, and more predictable.
- Standardised operational procedures and conditions
- Simplified and faster authorisation process
- Specific technical and operational requirements for drone and mission
When is an STS Applicable?
From 23 April 2025, the United Kingdom replaced the previous Operational Safety Case (OSC) route with UK SORA for Specific Category drone operations. Standard Scenarios now serve as a streamlined method to obtain operational authorisation when your planned operation fits the defined parameters and your drone complies with the requisite 'C' class labelling (e.g., C5 or C6).
If your intended drone operation aligns with a published STS, you can submit a declaration of compliance with that STS to the UK CAA as the basis for your operational authorisation application.
- Identify the matching STS for your operation
- Ensure your drone has the correct C-classification (C5 or C6)
- Submit the declaration to the UK CAA to begin operation
Benefits of Choosing an STS
Choosing an STS offers several advantages over preparing a full bespoke risk assessment such as SORA or PDRA:
Following a recognised STS removes the need to produce a separate, one-off risk assessment, streamlining and accelerating the authorisation process. Operators benefit from clear, predefined requirements which reduce ambiguity and ease compliance checks by the UK CAA.
Moreover, standardised operational conditions improve safety by targeting known risks effectively, and they provide transparency for the regulator which can facilitate smoother oversight.
- Quicker and simpler authorisation process
- Consistent and well-defined safety procedures
- Reduced administrative and risk assessment workload
- Improved regulatory clarity and communication
Practical Considerations for UAS Operators
Before opting for an STS, confirm that your drone is correctly classified according to UK 'C' class labelling, and verify that your operation conforms fully to the defined conditions of that STS. This includes checking the type of environment, line of sight requirements, geographic restrictions, and deployment of observers or other safety mitigations as specified.
If your operation does not fit an STS, you will need to prepare a detailed Concept of Operations (ConOps) and undergo the UK SORA or PDRA risk assessment process to apply for an operational authorisation. This route can involve greater complexity and lead times.
Stay informed on any additional UK-specific rules and consult early with the UK CAA if there is uncertainty, helping to avoid delays or refusals.
- Check your drone’s C-classification (C5 or C6)
- Assess whether your operation meets the STS conditions
- Consider UK SORA or PDRA assessment if your operation deviates
- Plan for ongoing compliance and operational oversight
Summary Checklist for Choosing an STS
Use this checklist to quickly determine whether an STS is appropriate for your drone operation:
1. Does your operation fall within the scope described by STS-01 (Visual Line of Sight in populated areas) or STS-02 (Beyond Visual Line of Sight in sparsely populated areas)?
2. Is your drone equipped with the correct C-label (C5 for STS-01, C6 for STS-02)?
3. Have you fully evaluated the operational limitations and conditions of the applicable STS and confirmed your operation can comply?
4. Are you able to submit a formal declaration of compliance with the STS to the UK CAA?
- 1. Operation within defined STS scenario?
- 2. Drone has required C-class label?
- 3. Compliance with all STS operational requirements?
- 4. Declaration submitted to UK CAA?
Frequently asked questions
What is the difference between STS-01 and STS-02?
STS-01 applies to Visual Line of Sight (VLOS) operations over a controlled ground area in a populated environment using drones with a C5 class label. STS-02 pertains to Beyond Visual Line of Sight (BVLOS) operations with airspace observers over a controlled ground area in a sparsely populated environment, requiring drones with a C6 label. Both aim to simplify authorisation via standardised scenarios.
Can I use an STS for operations outside the defined scenarios?
No. A Standard Scenario can only be used if your drone operation fully complies with the defined parameters and conditions of that STS. For operations outside these parameters, a full operational authorisation must be sought via the UK SORA or PDRA process.
Is a drone with a C-classification always required for an STS?
Yes. The drone must hold the required C-class label that corresponds with the STS to meet the mandatory technical safety standards. This classification is essential to the standardised operational safety conditions.
How do I apply for an STS declaration with the UK CAA?
You must submit a written declaration confirming compliance with all the stipulations of the chosen STS. The application should be made following the UK CAA’s official process. Refer to the UK CAA website for the current guidance and submission procedure.
Does DroneManual assist in preparing an STS declaration?
Yes, DroneManual offers practical guidance and template documents that support compiling your operational dossier, including the STS declaration. This can help you prepare effectively for the authorisation process.