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Simple requirements for approving the initial testing of small experimental aircraft in the UK are now available.

The requirements for experimental aircraft, known as E Conditions, will benefit small-scale aircraft designers and manufacturers by reducing the red tape and financial burdens associated with securing airworthiness and operational approval for new light aircraft designs, encouraging the growth of new design concepts.

The requirements allow aircraft designers to try out a new concept aircraft (up to a maximum take-off mass of 2,000 kg) in the air without going through the costly and time consuming procedures that currently exist to get a new design past the initial stage of proof-of-concept prototype. E Conditions can also be used to test aircraft modifications or if the aircraft is being operated in a manner or role that is previously unproven. If, after trying out a promising idea, it is thought to be viable, then a full certification programme can be planned and funded in the usual way.

Individuals and organisations conducting proof-of-concept flights will still be required to undertake a risk assessment to support the activity and in particular, ensure that the risks to third parties are adequately addressed. For example, flights would not be allowed over congested areas, the pilot must be suitably qualified and no passengers or cargo can be carried. Prior to the commencement of flight, an E Conditions Declaration must be submitted to the CAA relating to the flight test programme.

Noise Certificate Exemption

The CAA has been approved by the Secretary of State to issue a temporary exemption so that aircraft operating under E Conditions do not need to hold a noise certificate. This exemption, ORS4 No.1460, is in place until 31 January 2026. Please check back here for the current status of the noise exemption.

Fee Structure

The fee structure for an E Conditions Declaration submission is defined in the Scheme of Charges (Aircraft Registration).

Contact details

Email: ga@caa.co.uk
Telephone: 01293 573988