Single outward-leaning interplane struts were constructed around dural and spruce frames, with a plywood covering.

[1] The Racer was powered by a 1,250 hp (930 kW) water-cooled, X-24 cylinder Packard X-2775 loaned by the US Navy, a new design based on pair of V-12s with a common crankshaft.

Later wind tunnel tests showed the corrugations doubled the wing's drag, reducing the Racer's top speed by 20 mph (32 km/h; 17 kn).

Behind the engine the fuselage was a laminated spruce monocoque with an open cockpit aft of the wings faired rearwards into an integral fin with a rectangular rudder.

The forward strut was joined at the side of the engine mounting and the rear one met its opposite partner on the fuselage underside centre-line.

[2] Afterwards the Racer swapped floats for conventional, fixed, wheeled landing gear with faired legs.