Media and aviation industry hype about the sustainability of new flying technologies for air travel is overstated, a tourism expert said.

A new report by an international coalition of academics said ideas such as composite air-frames and biofuels had been heralded as making air travel greener.

Otago University Tourism Department head James Higham, who was involved in the study, said these initiatives would not work.

He said that while they are worthy ideas, they paled into insignificance compared to the sheer volume and growth of the aviation industry.

The report said by 2050 energy-use in aviation would account for 19 per cent of all transport energy, compared to 11 per cent in 2006.

This was in sharp contrast to industry pledges to reduce absolute emissions from aviation through technology, the researchers said.