Drone Class C1 UK Rules

What Is a Class C1 Drone?

Class C1 is the second-lightest EASA drone weight category. A drone bearing the C1 mark must have a maximum take-off mass (MTOM) below 900 grams. Unlike the lighter C0 class, C1 drones do not have a maximum speed restriction, but they must be designed so that the kinetic energy transferred to a person upon impact does not exceed 80 joules.

This 80-joule threshold is a critical design feature. It means manufacturers must build C1 drones with materials and structures that absorb energy on impact, reducing the risk of serious injury. The DJI Air 3, for example, sits in a weight range that could qualify for C1 marking with appropriate design verification.

Where Can You Fly a C1 Drone?

C1 drones operate in the Open A1 subcategory, which provides relatively generous flying permissions:

• Near uninvolved people: You may fly close to people who are not participating in your operation. However, you must not intentionally fly directly over them.
• Exception — 80-joule compliance: If the manufacturer has demonstrated that the drone can sustain a maximum of 80 joules of transferred energy upon impact, you are permitted to fly over uninvolved people. This is a design-certified feature, not something you can enable or modify yourself.
• Not over assemblies: As with all Open category drones, flying over organised gatherings of people is prohibited.
• Maximum altitude: 120 metres (400 feet) above ground level.
• Visual line of sight: Direct, unaided visual contact with your drone must be maintained throughout the flight.
• Flight Restriction Zones: FRZs around protected aerodromes are off-limits without CAA authorisation.

Training and Registration Requirements

Operating a C1 drone requires more preparation than a C0:

• Operator registration: You must register as a drone operator with the CAA. The annual fee is £10.33.
• Flyer ID: Complete the CAA's online theory test. This is the same free test required for camera-equipped C0 drones.
• Online training: Before flying a C1 drone in the A1 subcategory, you need to complete the CAA's online training module covering the specific rules for this class. This goes beyond the basic Flyer ID test.
• Operator ID display: Your Operator ID must be visible on the drone.

An A2 Certificate of Competency is not required for C1 operations. That qualification is specific to C2 drones flying in the A2 subcategory.

EASA C1 Mark in the UK — Transitional Rules

The C1 mark originates from EASA's regulatory framework. Post-Brexit, the UK CAA accepts EASA-marked drones during a transitional period. This means a drone carrying the C1 EASA mark can be flown in the UK under the same rules that would apply to a UK1-marked drone.

The UK has developed its own classification system ranging from UK0 to UK6. Once the transitional period ends, only UK-marked drones will be officially recognised. Drone owners should monitor CAA announcements for updates on transition deadlines and any changes to mutual recognition.

C1 vs C0 — Key Differences

• Weight: C0 is under 250g; C1 is under 900g. The heavier weight of C1 drones allows for better cameras, longer flight times, and greater wind resistance.
• Flying over people: C0 drones can fly over uninvolved people. C1 drones cannot — unless they meet the 80-joule energy transfer requirement.
• Training: C1 requires additional online training beyond the Flyer ID test that is sufficient for C0.
• Speed limit: C0 drones are capped at 19 m/s. C1 drones have no speed limit, but must meet the energy transfer design standard.

Who Should Choose a C1 Drone?

C1 drones suit pilots who need more capability than a sub-250g model can offer — better image quality, stronger wind handling, or longer flight endurance — without stepping up to the more restrictive A2 subcategory required for C2 drones. They are well-suited for aerial photography, real estate surveys, and light inspection work where you need to operate near but not directly above members of the public.

If your work requires you to fly directly over people on a regular basis, and the drone meets the 80-joule design standard, a C1 drone gives you that operational flexibility within the A1 subcategory.