Hybrid-electric cars have been quite popular for some time now, with an array of models currently present in the market. Whilst the market for 100% electric cars is also continuously expanding, the aircraft industry takes an important step in finally conducting successful tests with a significantly greener type of airplane.

According to CleanTechnica, the first hybrid airplane that can recharge its batteries took off this week. It is the product of airplane giant Boeing and Cambridge University researchers. The result is an airplane that 30% less fuel than a comparable 100% petrol plane. The test flights took place at Sywell Aerodrome near Northampton. The plane did a series of small hopes along the runway before taking off for evaluation flights at over 1,500 feet.

Continuing with a short technological explanation, hybrid engines combine a battery and a petrol engine. The plane’s petrol engine works with the battery-powered one at take-off and climb, when the plane needs extra power, but the electric motor can then switch into generator mode and recharges the batteries, or help the motor in minimizing fuel consumption.

Gizmag reports that the single-seat aircraft from Boeing, 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. Up until now, the main bottleneck impeding the development has been the price of batteries – but this is a factor undergoing rapid changes to the better.

Hybridization of planes has previously been too costly, but during the last years batteries have rapidly decreased in price. The development of hybrid or fully electrical planes has been held back while the researchers have awaited this drop, which means that from now on there is full speed ahead. The battery industry is currently undergoing a massive transformation and the development even made the recent Mashable list called “6 Trends for 2015 that will Change our Future”, as Mistbreaker earlier reported.

According to Boeing, six test flights have been conducted since 2012 and have proved the capacities of the demonstrator aircraft, including the exceptional fuel economy of the unique liquid-hydrogen propulsion system. Now, in January 2014, the hybrid-electrical plane called Phantom Eye received experimental status from the U.S. Air Force 412th Operations Group, allowing for expanded testing opportunities to bring this capability to market quickly.

Aviation is thought to be responsible for about 2 per cent of man-made carbon emissions. The aerospace industry made global commitments to take action that will see carbon neutral growth from 2020 and a net reduction in CO2 emissions of 50% by 2050 compared to 2005 levels. The researchers told The Independent that the technology is still far from able to be put on commercial airliners, but that the move is an important step. Fully electric aircrafts are probably decades away, but any progress is undoubtedly significant.