Alpaero’s Exel Goes Electric

Dean Sigler Electric Powerplants, Sustainable Aviation 2 Comments

Alpaero, a small firm in the southern French alps (hence its name?) created an ultralight sailplane/motorglider about 10 years ago that was originally powered by a two-stroke engine.  Recently, though, it’s gone green with a four-stroke, Briggs & Stratton engine and even greener with an electric motor version. Claude Noin, the designer, wanted to answer the request for a “light autonomous sailplane at a reasonable cost,” able to meet ULM (ultralight) qualifications.  The fixed engine behind the cockpit configuration avoids the complexity of the retractable engine configuration, which Alpaero says can increase drag two or even three times over that of the “clean” sailplane when the engine or motor is extended.  As Dick Van Grunsven has pointed out, the need …