Lucas L5  The Lucas L5 was a sport aircraft designed in France in the late 1970s and marketed for amateur construction. It was a conventional, low-wing cantilever monoplane with side-by-side seating for two in a fully enclosed cabin. Construction was of metal throughout, and the builder was given the option of fixed, tricycle undercarriage, or tailwheel undercarriage in which the main units were manually retractable.