Taking flight? Aviation's bumpy ride towards a green fuel future

A century ago, Francesco de Pinedo was attempting the unprecedented feat of crossing the Indian subcontinent in a flying boat.

- Gwyn Topham Transport correspondent

The Italian aviator later splashed down on the Tiber in Rome to national acclaim, having flown through Asia to Australia and back in seven months, taking off and landing in water 80 times.

Aviation history has been marked by stop-start journeys on hitherto uncharted courses to unlikely, if not unreachable, destinations. Today's collective act of faith - amid much scepticism - is in following an uncertain path to sustainability through green fuels that are yet to be widely produced.

Most in the industry, even if only through self-interest, are on board. Of the emissions cuts needed for carbon neutrality, 70% rely on sustainable aviation fuels (SAF).

"Without it," says Tim Alderslade, of Airlines UK, "we cannot get anywhere near net zero by 2050."

This year, the first steps were imposed by mandate in the EU and the UK, requiring 2% of jet fuel to be sustainable - by 2030, that reaches 6% in the EU and 10% in Britain.

However, airlines question whether supplies will be available and at what price. A fissure is developing between those that have secured sources of SAF and invested in the technology, and others with a ferocious eye on the bottom line.

Michael O'Leary, the chief executive of Ryanair, dismisses SAF as nonsense: "It is all gradually dying a death, which is what it deserves to do. We have just about met our 2% mandate. There is no possibility of meeting 6% by 2030; 10%, not a hope in hell. We're not going to get to net zero by 2050."