[2] The aircraft featured a flat, speedboat-like[3] hull with a square bow and with tailfins blended into each side.
[4][5] The fins were angled to form a butterfly tail and included no moving surfaces.
[5][6] The wings were mounted on struts, parasol-style, and also contained no moving surfaces.
[3][6] The flight controls consisted of a helicopter-style collective that varied the angle of attack of both wings simultaneously,[6][8][9] and a control wheel that varied their angles of attack in relation to one another.
[2] With friend Elliot Dalland, Spratt began construction of the prototype (registered N2236) in 1962.