Hydrogen Sandbox

Closed 10 Jan 2024

Opened 27 Nov 2023


The Civil Aviation Authority is inviting industry, academia, and organisations to join its Regulatory Sandbox to test hydrogen technologies that support the use of hydrogen as an aviation fuel. The tests will identify hazards, risks, safety challenges and gaps in current CAA regulations and evaluate the proposed mitigations through verification and validation.   

Our intention is that the hydrogen sandbox will enable appropriate stakeholders to test hydrogen technologies and show how the proposed mitigations will either comply with or close gaps in current CAA regulations. This outcome of testing will enable the proposal of recommendations to create new hydrogen policies.

The call is open to individual organisations or consortia working on developing and using hydrogen as an aviation fuel.

What happens next

The application period for this sandbox will close on Wednesday, 13 January 2024 at 12:00 hrs GMT. Applications received after this time will not be accepted.

Applications will be reviewed and assessed for inclusion in the sandbox and all bidders will be notified within 7 working days of the outcome.

Successful bidders will be onboarded to the sandbox.

A virtual kick-off meeting will be arranged within 10 working days of notification of onboarding to the sandbox to explain the next steps to all parties.

Individual one-to-one meetings will be held to provide feedback on the proposed ConOps and establish a project timelines.

The sandbox will only be opened once, and once the application phase has closed, no other applications for this sandbox will be accepted.


  • General Aviation
  • Commercial airlines
  • Military
  • Airport operators
  • Ground handling providers
  • RFFS Training Providers
  • Training organisations
  • Regulatory bodies
  • European Aviation Safety Agency
  • International Civil Aviation Organization
  • National representative organisations or institutes


  • Rescue and fire fighting