The Deltacraft MD-40 was designed to comply with the Fédération Aéronautique Internationale microlight category, including the category's maximum gross weight of 4500NaN0. The aircraft has a maximum gross weight of 3400NaN0. It features a cable-braced hang glider-style high-wing, weight-shift controls, a single seat open cockpit with a streamlined cockpit fairing, retractable tricycle landing gear and a single engine in pusher configuration.
The aircraft fuselage is made from composites, with its aluminum-framed double surface wing covered in Dacron sailcloth. The wing is supported by a single tube-type kingpost and uses an "A" frame weight-shift control bar. The powerplant is a twin cylinder, air-cooled, two-stroke, dual-ignition 500NaN0 Rotax 503 engine. The MD-40 has an empty weight of 1600NaN0 and a gross weight of 3400NaN0, giving a useful load of 1800NaN0. With full fuel of the payload is 1600NaN0.
A number of different wings can be fitted to the basic carriage, including a wing with an area of 16.7m2 produced by the company.
