Aircraft

Hybrid-electric aircraft takes to the skies

Hybrid-electric aircraft takes to the skies
The University of Cambridge and Boeing have partnered to create an electric-hybrid test aircraft (Photo: University of Cambridge)
The University of Cambridge and Boeing have partnered to create an electric-hybrid test aircraft (Photo: University of Cambridge)
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The aircraft is said to be the first capable of recharging its batteries in flight (Photo: University of Cambridge)
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The aircraft is said to be the first capable of recharging its batteries in flight (Photo: University of Cambridge)
The aircraft is said to be the first capable of recharging its batteries in flight
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The aircraft is said to be the first capable of recharging its batteries in flight
The University of Cambridge and Boeing have partnered to create an electric-hybrid test aircraft (Photo: University of Cambridge)
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The University of Cambridge and Boeing have partnered to create an electric-hybrid test aircraft (Photo: University of Cambridge)
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We're all familiar with hybrid cars, but hybrid planes are virtually unheard of. Now though, researchers from the University of Cambridge, UK, have partnered with Boeing to test what they say is the first hybrid-electric aircraft. It is said to use 30 percent less fuel than a gas-only equivalent.

"Although hybrid cars have been available for more than a decade, what's been holding back the development of hybrid or fully-electric aircraft until now is battery technology," says project lead from Cambridge's Department of Engineering Dr Paul Robertson. "Until recently, they have been too heavy and didn't have enough energy capacity. But with the advent of improved lithium-polymer batteries, similar to what you’d find in a laptop computer, hybrid aircraft – albeit at a small scale – are now starting to become viable."

Gizmag is no stranger to hybrid aircraft. Volta Volaré promised its hybrid four-seater GT4 back in 2012, while just last month we featured the Faradair BEHA concept that will theoretically be powered by electric motors and a bio-diesel engine. The Cambridge/Boeing test plane is a much simpler design than both of those, however.

The aircraft is said to be the first capable of recharging its batteries in flight (Photo: University of Cambridge)
The aircraft is said to be the first capable of recharging its batteries in flight (Photo: University of Cambridge)

The single-seat aircraft, which is based on a commercially-available model, is powered by a Honda 4-stroke piston engine and a custom-made electric motor/generator. The two power sources are coupled so that either can drive the propeller. At times when a lot of power is required, such as during take-off, the plane uses both the engine and the motor to drive the propeller.

Once it is at cruising height, however, the motor can continue to assist the engine to help save fuel or be switched into "generator mode" and for it to recharge the batteries while the plane is in flight. According to the University of Cambridge, this is the first time that this has been achieved. A module designed by the engineering department at Cambridge is used to control electrical current to and from the lithium-polymer cell batteries, 16 of which are housed in compartments in the wings.

The hybrid aircraft was tested at the Sywell Aerodrome, near Northampton, UK. Initial tests comprised a series of "hops" along the runway. These were then followed by longer flights at an altitude of over 1,500 ft (457 m). Ongoing tests are aimed at optimizing performance and fuel economy.

The video below provides an introduction to the hybrid plane project.

Source: University of Cambridge

Planes go hybrid-electric

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5 comments
5 comments
watersworm
Hybrid, with more and more efficient combined motors of course, that's the future. Pure lectrical planes , Seems too hypotetical except for small very short range ones. Solar Impulse is "just" (!) a technological display, and a great one, but, IMO it's essentailly a "breaking news" maker.
arationofreason
I think they are playing a zero sum game other than precharging the batteries on the ground for take off. Then unlike fuel weight which burns off the battery dead weight lasts forever. Just what is their plan to make such a scheme more than a technology demonstration?
ezeflyer
As batteries get lighter, hybrid aircraft are becoming more practical. Adding photovoltaics will extend their range. Strong, lightweight composite construction will also help. Now if they can come up with comfortable airline seating, they will really have something.
Esteban Sperber Frankel
Why not with a gyroplane?, by take off you need the petrol + electric engine by flying you need less gas ith battery charge by moving the rotary wings in the top where is the generator, this could be a hybrid gyroplane which needs less track to take off than a common plane, the batteries could be behind the seats.
Dawar Saify
For actual benefit of the current model: 1. Light weight solar panels could be added. 2. plus gaining energy while gliding or the engines could be shut off. Apart from this, currently there is no net gain as the engine is being used to recharge the batteries, drawing power from propeller propulsion, again relying on the energy density quality of the hydrocarbon fuel, and it's loss of weight, and not on the quality of the batteries. This defeats the purpose. For the future this can be improved upon as above 1 and 2, plus as mentioned, better energy density of batteries. In the future: 1. Better light nano material structure, nano tech high density batteries, better solar panels, nano tech extremely low friction engine and motor, super conducting wiring. 2. Even higher density fuels.