Demoichelle Ultralight a Mix of Old and New
Electric-powered version of the Demoichelle
The Demoichelle ultralight has an old-time look because it was inspired by the Santos-Dumont Demoiselle of 1908. However, its design, construction, and performance are in line with modern ultralights. The Demoichelle is the latest design coming from Daniel Dalby at the Association for Promotion of the Flying Ladders. The movement began in Europe as a way to build ultralights with minimum cost and building time using conventional aluminum ladders as structural components for the fuselage or even wings.
They no longer use actual ladders in the airframe. After 120 sets of plans were sold for the Pouchel, their first “ladder plane,” the ladder manufacturer objected. Subsequent designs including the Demoichelle follow the ladder concept by relying heavily on extruded aluminum.
The ultralight in the photograph is the electric-powered version called the Demoichellec, which first flew in April of 2010 and made the news when it flew at the Green Aviation Show at Le Bourget Airport in Paris, France. The original internal combustion-powered Demoichelle made its first flight in August of 2009. You can see videos of both versions flying in the multimedia tab at the APEV website. While there, check out the other airplanes and read the history of the ladder airplane movement.
The wing has a single main spar, which is an aluminum extrusion of about 2 x 4 inches. The ribs are foam and wood, and the leading edge is composite. The wingspan is 26.5 feet, and the wing area is 107 square feet, giving a cruise speed of 55 mph and a maximum gross weight of 550 pounds. All of the previous aircraft from APEV were two-axis, tandem-wing Flying Flea derivatives. The Demoichelle uses three-axis control but avoids the complexity of ailerons by pivoting the wings differentially up two degrees and down four degrees for roll control. The construction methods adopted to minimize building time on their Pouchel series of airplanes were also utilized in the Demoichelle. Those details and the wing pivoting mechanism are available in the plans, priced at 100 Euros or about $125. An airframe kit is available for 5,000Euros or about $6,300.