Question to the Ministry of Defence:

To ask the Secretary of State for Defence, what estimate he has made of the additional cost to the public purse of the Royal Air Force transitioning to 100 per cent sustainable aviation fuel by 2040; and whether his Department has undertaken any assessment of the long-term fiscal implications of sustainable or synthetic aviation fuel prices for Defence aviation.

The Royal Air Force (RAF) procures its aviation fuel in the UK from commercial suppliers at market rates. As a result, this makes accurate long-term cost forecasting challenging. The price of aviation fuel, including Sustainable Aviation Fuel (SAF), is subject to market fluctuations, and the level of RAF fuel consumption varies due to numerous factors.

The RAF has not committed to transitioning to 100% SAF by 2040. The RAF will follow the incremental transition to sustainable aviation fuel as set out in the UK Government's SAF mandate, which requires aviation fuel to contain 22% SAF by 2040. This date aligns with the RAF's aim to become a net-zero air force.