Both were two-bay tractor biplanes with unstaggered parallel-chord wings with rounded tips, a deep rectangular section fuselage bearing rectangular steel-framed stabilisers, elevators and rudder with no fixed fin, and an undercarriage with a pair of wheels on a transverse leaf-spring and a long central skid projecting forward of the propeller.

It had a square rather than triangular cross section fuselage, simplifying construction and allowing the crew seats to be lower down, giving more protection.

The wings were supported using an aerodynamically cleaner ordinary two-bay layout, replacing the two and a half bay arrangement of its predecessor, which had a third pair of interplane struts close to the fuselage.

The wire-braced high aspect ratio two-bay wings had ash spars and poplar ribs with the curved ends formed from cane.

A sprung tailskid was mounted below the rudder and small hoops were fitted below the outer interplane struts to protect the wingtips.

[3] Both were water-cooled engines, with pairs of large coiled tube radiators positioned parallel to the fuselage on either side of the front cockpit.

motor was fitted and on 10 March 1912 Duigan, flying solo managed some long, straight flights in his too-evidently underpowered machine.

However, its performance was not up to Roe's expectations, and a second example was built, modified to take the much lighter 50 hp (37 kW) Gnome air-cooled rotary engine.