An experimental electric plane with no moving parts has been successfully designed and flown by scientists in the US.
Instead of propellers or turbines, the five-metre wide craft used electricity to generate something called the "ionic wind" which sent it 60 metres (200ft) through the air.
Weighing just under 2.5kg (5.4lbs), the balsa wood concept is a huge step towards a future in which aircraft can operate without combustion emissions.
Known only as Version 2, the plane was powered by a process called "electroaerodynamic propulsion" which was first proposed in the 1960s.
Electroaerodyamic propulsion uses very high voltages – in the case of the plane 40,000 volts – to generate ions in the air around two electrodes.
Ions – atoms which have an electrical charge – travel through the air between these two electrodes, colliding with the molecules in the air while doing so and producing the so-called ionic wind propelling the plane forward.
Led by Dr Steven Barrett, the researchers from the Massachusetts Institute of Technology (MIT) have published a paper in the journal Nature about their experimental craft.
Dr Barrett came up with the prototype after reexamining the 1960s research in 2009, and told MIT Technology Review he was "inspired by the science fiction ideas of planes and spacecraft. I thought about what physics could allow that."
It has taken him just under a decade to build a flying plane, and there remains a long way to go before the ionic wind can deliver enough thrust to lift a commercial jet rather than a 2.5kg plane being flown away from the wind and for only 12 seconds.
"Although it is still a long way off from commercial gas turbine propulsion… electroaerodynamic propulsion has the potential to be a game-changer for short-range, small-payload drone flights," said Dr Priyanka Dhopade, a researcher at the Oxford Thermofluids Institute.
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"We've only had a few years to develop this technology," said Dr Barrett, adding: "conventional propulsion has had 100 years, so we have some catching up to do. But I think we can".