If you are searching for the CAA Operational Safety Case, the most important thing to know is that you can no longer apply for one. On 23 April 2025, the Civil Aviation Authority replaced the OSC with a new method called UK SORA.
That change matters for any business planning drone operations beyond basic Open Category flying. Organisations that hold an OSC-based authorisation need to plan their renewal, and anyone seeking CAA drone approval for the first time needs to know which of today’s two routes applies to them.
This guide explains what the OSC was, what replaced it, how the current routes work, and how to choose the right one for your operation.
What Was the CAA Operational Safety Case?
The Operating Safety Case, widely known as the Operational Safety Case or OSC, was the CAA’s former method for applying for an Operational Authorisation in the Specific Category. It was set out in CAP 722A.
An OSC was largely a written, narrative document. The operator described the operation, identified the hazards and explained how each would be managed. For years it was the main route for operations beyond the standard permissions, such as flying closer to people or in more complex environments.
What Replaced the OSC?
The OSC was replaced by UK SORA (Specific Operations Risk Assessment) from 23 April 2025. The CAA closed the OSC application service to new submissions at the same point.
UK SORA is based on the international JARUS SORA methodology and published by the CAA as CAP 3017. The biggest difference is how risk is assessed:
- OSC: a narrative risk assessment, written around the operator’s own description of the operation.
- UK SORA: a structured, step-by-step method. It scores the ground risk and air risk of the operation, assigns a Specific Assurance and Integrity Level (SAIL), and sets the safety objectives the operator must evidence.
The result is a more consistent process. It is also more demanding: every claim in the application needs evidence that fits the specific operation.
What If You Already Hold an OSC-Based Authorisation?
Your authorisation is not cancelled. An existing OSC-based Operational Authorisation remains valid until its expiry date, and you can still apply for variations to it while it is live.
The change comes at renewal. When your OSC-based authorisation expires, you cannot simply renew the OSC. You will need to apply either for PDRA01, if your operation fits within its limits, or for a new UK SORA-based authorisation.
A UK SORA application is not a reworded OSC. It needs your operation re-assessed under the new methodology, so it is worth starting well before your expiry date.
How to Get CAA Drone Approval Today: PDRA01 or UK SORA
Every Specific Category operation needs an Operational Authorisation from the CAA before you fly. There are now two main ways to get one: PDRA01 or UK SORA.
PDRA01: the standard route
PDRA01 is a pre-defined risk assessment. The CAA has already assessed the risk, so you apply to operate within its fixed limits rather than building your own case. It is the simplest route and covers a large share of everyday commercial work.
Under PDRA01 you can:
- Fly drones from 250g up to 25kg
- Operate within visual line of sight, no more than 500m from the remote pilot
- Fly in residential, commercial, industrial and recreational areas, subject to airspace restrictions
- Stay below 120m (400ft), with limited exceptions near tall structures
You must keep 50m from uninvolved people (30m during take-off and landing) and must not fly over crowds. Remote pilots need a GVC or RPC-L1, and the operator needs an operations manual. PDRA01 currently costs £524 a year and lasts 12 months.
Typical PDRA01 work includes roof and building inspections, site photography and surveys of recreational sites.
UK SORA: for everything beyond PDRA01
If your operation falls outside PDRA01’s limits, you need a UK SORA-based authorisation. The CAA gives these examples:
- Flying beyond visual line of sight (BVLOS)
- Flying close to crowds
- Dropping items from the drone
- Flying above 120m (400ft)
- Swarm operations
- Flying close to people with a legacy drone over 250g
Which route do you need?
If your operation Route
- Fits the Open Category limits No Operational Authorisation needed
- Is VLOS, uses a drone of 250g–25kg, and stays within PDRA01’s distances and heights PDRA01
- Goes beyond PDRA01 in any way (BVLOS, crowds, height, heavier aircraft, dropping items) UK SORA
If you are unsure which side of the line your operation falls on, get that answer before you buy equipment or start an application. Choosing the wrong route is one of the most common causes of wasted time.
Authorisation vs Pilot Competence: Not the Same Thing
An Operational Authorisation and a pilot qualification do different jobs, and you need both. The authorisation is held by the organisation and sets the scope, conditions and limits of what it may do. The qualification is held by each remote pilot and shows they are competent to fly within those limits.
The CAA now recognises four Specific Category pilot qualifications:
Qualification What it covers
- GVC VLOS operations
- RPC-L1 VLOS (Part A), plus BVLOS with visual mitigations (optional Part B)
- RPC-L2 BVLOS where no other air traffic is expected, such as close to infrastructure
- RPC-L3 BVLOS in more complex airspace shared with other traffic
Two points matter for planning:
- The GVC will stop being issued on 31 December 2027. Existing GVCs remain valid until they expire, where an Operational Authorisation accepts them. New pilots will move onto the RPC framework.
- Your authorisation sets the minimum. Each Operational Authorisation states the pilot competence it requires, and it may add extra conditions such as logged flying hours.
If you are also planning BVLOS work, our guide to BVLOS drone operations in the UK explains the higher competence levels in more detail.
Why Businesses Get Expert Support
UK SORA applications succeed or stall on the quality of their evidence. The CAA expects a clear Concept of Operations, ground and air risk assessed for your specific sites, and procedures that match how your team actually works. Generic content leads to questions, revisions and delays, which is costly when operations are waiting to start.
At Enefftech, our UAV consultancy helps organisations:
- Work out whether PDRA01 covers their operation or whether UK SORA is needed
- Plan the move from an expiring OSC-based authorisation to the right current route
- Build the Concept of Operations, risk assessment and procedures a UK SORA application needs
We have supported organisations including nuclear facility operators and critical infrastructure providers, so we understand the level of evidence the CAA expects for safety-critical work. Our CAA-recognised training then gives your pilots the competence their authorisation requires.
Get the Right Authorisation First Time
Whether you hold an OSC-based authorisation that is due for renewal, or you are applying for the first time, the starting point is the same: understand which route your operation really needs.
Contact Enefftech to discuss your operation and your Operational Authorisation requirements.
Frequently Asked Questions
Can I still apply for a CAA Operational Safety Case?
No. The CAA stopped accepting OSC applications on 23 April 2025. New Specific Category applications use either PDRA01 or UK SORA.
Is my existing OSC-based authorisation still valid?
Yes, until its expiry date. You can also apply for variations while it is live. When it expires, you will need to apply through PDRA01 or UK SORA instead.
Do I need UK SORA for BVLOS?
Yes. Flying beyond visual line of sight is outside PDRA01 and requires a UK SORA-based Operational Authorisation, along with higher pilot competence than a GVC.
Is a GVC the same as an Operational Authorisation?
No. A GVC is a pilot qualification. The Operational Authorisation is the organisation’s permission to carry out a particular type of operation. You need both.
