the exact date of the week-end's first flight is not known but it was undergoing early flight trials at the start of july 1935. at that time it was powered by the smaller, ava. two had been built by early july and later that month, when the first week-end's tests had proved very successful, a third example was under construction. this was to be powered by a train 4t four cylinder, air-cooled, inverted in-line engine producing . it was designated the gaucher rg.40t.