The UCL ATSlab recently carried out a study looking at the market feasibility of UK domestic hydrogen aircraft operations as part of the NAPKIN project (led by Heathrow Airport, with Rolls Royce as a partner). This work, which demonstrated the conditions under which airlines can cost-effectively operate small hydrogen aircraft, was cited by Rolls Royce in its recent announcement at Farnborough Airshow of a new hydrogen programme. The NAPKIN final report is due to be released soon – watch this space!