A study published by the Royal Society has questioned the viability of UK government and airline plans to shift from oil and kerosene to alternative or "green" fuels.
The report said that the availability and accessibility of sustainable feed-stock for all options for such fuel, usually known as sustainable aviation fuel (SAF), remains "a key challenge".
Other avenues, such as the efficient production and storage of hydrogen and ammonia, need more research and development, according to the team that wrote the report, which said that although "low carbon emission jet fuels are to have a strong positive impact on the UK’s Road to Net zero", the replacements should "not cause unacceptable collateral ecological damage
What the group said were "non-CO2 climate impacts" of other fuels would also need to be looked into, as would the need for handling multiple technologies at airports and by carriers.
"Staff and crew will need specialised training on handling alternative fuels, and the public will need to be informed about the relevant safety concerns within the airport and aircraft," said the team, which was chaired by Graham Hutchings, professor of chemistry at Cardiff University and included 14 other scientists at universities across the UK, including Oxford and Imperial College London.
"Some of the science exists, and some of it doesn't", said Hutchings, who warned " we need a cleaner fuel".