In previous articles in EVR we have described the new electric stunt plane from EADS in France and the production pure electric sport plane from in China. Here we wind the clock back a little to show how the early work on pure electric aircraft is spawning many other very different aircraft, a common factor being the use of lightweight lithium polymer batteries that need no metal enclosure.
Early work in Japan
From 1960 to 2006 there were over 60 projects where sailplanes and gliders, relying on lift from the air, were motorised electrically to assist the process. Then came pure electric fixed wing planes that could take off and land entirely powered by the electric motor.
In 2006, the Japanese flew the first pure electric manned aircraft.
Source: Tokyo University
It used 160 Panasonic Oyxride Oxy Nickel Hydroxide AA batteries, and it only flew for less than a minute, covering nearly 400 meters (428 yards). The wings stretched a full 31m (102'). It was piloted by 53 kg (117 lb) Tomohiro Kamiya, from the Tokyo Institute of Technology. After that, the development of pure electric aircraft used lithium batteries all the way.
Electra in France
In 2007, a single-seater airplane of standard construction called Electra took to the sky, this time in France. Anne Lavrand, the president of the APAME group, said. "This will be a real aeroplane that will have an airworthiness certificate. It's a machine built for anyone with a pilot's license."
Other details were:
- Brush Industrial motor (designed for pure electric golf cars) by LMC in the UK 18 kW (25 hp)
- Power Electronics developed specifically for this use
- Lithium Batteries - Polymer by Kokam in Japan (total weight: 47 kg)
- Propeller-step adjustable ground ARPLAST suited to this engine
- Scoreboard, throttle, engine mount, flange motor, etc.... developed and produced specifically for this device
APAME is the Association for Promotion of Electrically Driven Aircraft in France (Association pour la Promotion des Aeronefs a Motorisation Electrique).
Shown below, Anne Lavrand, Project Manager of Electra received the Award for Technological Innovation - Prototype Class of the Aero-Club de France in 2008.
In 2009, an exceptionally low cost Ukrainian made motorised glider, the Alatus - M Electric 44 - AOI, was demonstrated, again with lithium polymer batteries. It can fly in still air and it is also produced in France by Randkar of Frossay (Loire Atlantique), equipped with a 26 hp electric drive developed by ELECTRAVIA.
In January 2009, the motorglider Alatus - M Electric 44 - AOI successfully completed its first test from the airfield Vaumeilh Sisteron (Alpes de Haute Provence). Subsequently, PC-Aero has announced an atttractive pure electric sport plane.
Among the manufacturers of lithium polymer traction batteries are ABAT, China BAK, Dow Kokam, Electro Energy, Electrovaya, Kokam, LGChem/ Changan New Energy Automobile joint venture, LG Chem and its Compact Power subsidiary and the LG Chem/ Hyundai Mobis joint venture and Lishen. 18 manufacturers of such batteries are listed with their business contacts in a forthcoming free white paper by IDTechEx. Lithium polymer batteries are now used in aircraft, many forms of land vehicle including military and many forms of water going vehicle including Autonomous Underwater Vehicles AUVs, where light weight, pressure resistance, long life and other benefits are valued.
Image: Motorglider Alatus - M Electric 44 - AOI