At the recently concluded Palm Springs Expo, a keynote address was provided by George Bye, the man behind the Sun Flyer project that aims to put electric two seaters into flight schools. Pipistrel is already selling into this market with its Electro (video) and while only a small number of aircraft are in use, the race is on for more … much more.
Airbus made big news back in July when a race developed to see who would cross the English Channel first in an electric powered airplane. Of course, the whole thing was a bit moot because it had been done years before. Longtime electric pioneer Eric Raymond of Sunseeker Duo noted, “It was already done in 1981 by the Solar Challenger, which flew from Paris to London at 14,000 feet. [Famous hang glider pilot and manufacturer Gerard] Thevenot even flew an electric trike across.
Both 2015 flights crossing the English Channel (around 20 miles over water or a bit over 30 as E-Fan flew) seem rather modest compared to the ocean-spanning attempt by Solar Impulse 2.
Airbus’ E-Fan 1.0 flew 46 miles to Calais in France in 36 minutes at an altitude of about 3,500 feet. The tandem two-seat E-Fan uses a wingspan of 31 feet that produces a 16:1 glide. Its twin ducted electric motors with variable-pitch propellers are powered by a series of 250-volt lithium-ion polymer batteries. Hugues Duval’s miniature airplane, the Cri Cri, beat E-Fan to Calais by about 12 hours. The tiny aircraft has only a 16 foot wingspan lifted by two 35-horsepower Electravia electric motors. Cri Cri flew at 65 mph. According to reports, Duval’s Channel crossing took only 17 minutes, which was good as his battery life was said to be 25 minutes. He benefitted from being launched by another airplane (see earlier article).
A third electric Channel-crosser, Pipistrel, was denied a chance to beat them both when electric motor maker, Siemens, suddenly refused to allow the company to fly its motor over water (though one wonders how the motor was supposed to know it was no longer over land where it performed just fine). Here’s an earlier article about Pipistrel’s WATTsUP, since renamed Electro.
All the corporate race-across-the-Channel drama notwithstanding, the future for electric power has the smell of inevitability, if for no other reason than giant Airbus dropping tens of millions into their development. Why would they make such an investment? Simple: electric airliners are in their future. Airbus stated its goal of creating a 100-passenger electric hybrid planes that could enter service by 2030. I’ll discuss that below (also see image).
The advantages of electric propulsion are several, according to Airbus: lower noise that doesn’t bother airport neighbors; reduced carbon dioxide (CO2), nitrous oxide (NOx), and particulate emissions; and, reduced vibration. All three benefit the pilot as well. For example, when I flew the eSpyder, lower noise was more pleasant and made me aware of noises on the ground that I would never have heard with a headset on and a reciprocating engine roaring. Less vibration is also not only a lesser wear factor for airframes but also for engines and the pilot will benefit physiologically. You might not notice reduced emissions as viscerally but cleaner air surely benefits everyone.
Airbus Group plans what they call the “world’s first series production electric planes,” specifically E-Fan 2.0 and 4.0 aircraft, the latter being a four seater. Work on the new all-electric, battery-powered two-seater pilot training version and the four person hybrid electric motor/combustion engine version will be pursued by Voltair SAS, a wholly-owned subsidiary of Airbus. The two models will be built at a 16,000 square foot facility located at Pau Pyrénées Airport in the southwest of France, sometimes called “Aerospace Valley.”
Construction of the E-Fan assembly line is to start next year and a first E-Fan 2.0 should fly in late 2017. Airbus Group committed about $22 million for development of the E-Fan 2.0 production aircraft. They will build to European CS-LSA certification using ASTM standards at a gross weight of under 600 kg (1,320 pounds). So, the two seater will be a Light-Sport Aircraft even if it may not be called that. The hybrid four seat E-Fan 4.0 is targeting 2019.
Spending by jet engine maker Rolls Royce began in 2012 with nearly a billion dollars for metals, composites, vehicle integration, electronics, systems engineering and information technologies. Airbus joins with Rolls Royce and others, all captioned under something called the DEAP project for Distributed Electric Aerospace Propulsion. Their goals include reducing CO2 emissions by 75%, NOx by 90%, and noise by 65% compared to standards in 2000.
As the nearby image shows, the airliner concept involves three ducted fan motors on each side of the fuselage (looking much like the E-Fan’s motors though much larger). Such a system will obviously required a far higher level of integration with the airframe than just slinging a high bypass jet engine under the wing. An advanced gas-powered unit would provide power for the six motors buried in the wings. Airbus refers to this a “serial hybrid propulsion system.”
Coming back to the present day to the smaller airplanes that fascinate readers of this website (and those who watch our YouTube videos), you might wonder, “Why spend time on projects aimed at 2030 to 2050?” All you need do is consider how giant companies spending many hundreds of millions of dollars can result in developing technologies useful for Light-Sport Aircraft, light kits, and ultralights.
Although we already have electric-powered ultralights that work quite well for single pilots (see short article here and here; a video; or, a full-length article) and while we have emerging LSA that should do duty as flight trainers and local area fun flying, taking bigger strides is necessary for an airline design. Such esoteric ideas as superconducting machines (motors) and cryogenic cooling intended for airline use may be tested on LSA and light GA planes.
While all this sounds rather far-out, a kind of science fiction story, the urgency for lower emitting, quieter airliners, and what will surely be escalating fuel costs may drive some interesting concepts that small airplane makers can use.
Small companies can be very nimble and may more quickly employ ideas behemoth companies like Airbus and Rolls Royce can’t put into use for years. I can’t fully imagine where this electric future leads us but electric power for aircraft is certainly coming.