Flight of the electric Demoichelle
Despite the 10-15 knot winds cutting across the airfield at Le Bourget in Paris for the Green Air Show, visitors were treated to the wonderful sight of the electric Demoichelle in the air. The treasured creation of the Association for Promotion of Flying Ladders (APEV) the electric monoplane looks as though it was designed by the ghost of Alberto Santos-Dumont himself.
APEV's Charles Donnefort told Gizmag that the electric aircraft on display underneath Concorde (when it wasn't on the airfield) at the Le Salon de l'Aviation Verte in Paris is in fact the same prototype used for the test flights of the group's original combustion-powered Demoichelle in 2009, with a few modifications. The ROTAX engine has been swapped for a reinforced AGNI 112 R electric motor and some Lithium Polymer KOKAM 74V batteries, plus there's a minor size alteration too.
The single spar, 50x100mm aluminum extrusion, wooden reinforced Styrodur rib, composite leading and trailing edge, and DIATEX 1000 covering which makes up the wings has received an extra half a meter on each side to give a little more wing surface, taking the wingspan to over 9 meters (29.5 feet). The actual weight of the e-Demoichelle is almost exactly the same as the thermal version, with the electric motor and the batteries making up for the heavy ROTAX engine.
In common with its predecessor, it stands around 2 meters (6.8 feet) tall and is just over 5 meters (17.3 feet) in length with the pilot sitting below the wing. The stall speed is marginally different, the electric version now between 35 and 40 kph (21.7/24.8 mph) but the maximum speed is still 120 km/h (74.5 mph) although the pilot usually takes things a little easier, with an average cruising speed of around 70kph (43.3 mph).
In the coming months APEV will be busying themselves creating a two-seater biplane (the Hydrochel) and a modern replica of the Piper Cub (the Cubchel). The electric Demoichelle's next public appearance will be in September at the Salon ULM Blois.