A modified Kelly-D was developed on the basis of experience with these aircraft, to offer greatly improved ground handling and a lower landing speed. It used a new wing section and has a 2 ft (61 cm) increase in span. This version became the only one released for home building and pre-welded component parts for the Kelly-D were available, the details below refer to it. At least fifteen Kelly-Ds have been constructed.
The pictured aircraft was constructed by Rogers and subsequently registered to Robert D. Robinson of Warrensburg on February 22, 1985, the aircraft was listed as a Robinson/Rogers Kelly-D; the aircraft changed hands on September 19, 1992. Latest owner, since December 16, 2013, is Larry Plank of Perkins, Oklahoma.
TYPE: Two-seat homebuilt aerobatic biplane.
AIRFRAME: Single-bay biplane, with wire braced N type interplane struts each side. Inverted V-center-section struts and streamline section landing and flying wires. Wing section NACA 4412. Dihedral 3°, on lower wings only. Incidence 2° on both wings. Constant chord, with no sweepback but considerable stagger. Wooden two-spar structure, with fabric covering. Aerodynamically balanced ailerons of wooden construction, fabric covered, on lower wing only. Conventional welded steel tube fuselage and wire braced tail unit, with fabric covering. Fixed incidence tailplane. Trim tab in port elevator.
LANDING GEAR: Non-retractable tailwheel type. Two side Vs and half-axles hinged to fuselage structure. Shock absorption of main units by steel coil spring on each compression strut. Mainwheel tires size 6.00-6, pressure 1.24 bars (18 lb/sq.in, 87.89 kg/sq.m). Tailwheel diameter 6 in (15 cm). Cleveland hydraulic disc brakes. Fairings over mainwheels optional.
POWER PLANT: An 115 hp Avco Lycoming O-235 flat-four engine, driving a Sensenich two-blade fixed-pitch propeller. Fuel tank in fuselage, aft of firewall, with capacity of 24 gal (91 l). Refuelling point on upper surface of fuselage, forward of front cockpit. Oil capacity 1.5 gal (5.7 l).
ACCOMMODATION: Two seats in tandem in open cockpits. Baggage space aft of pilot's seat in rear cockpit, capacity 40 lb (18 kg).
SYSTEMS: Hydraulic system for brakes only. Electrical system includes starter/generator and 12V storage battery.
AVIONICS AND EQUIPMENT: Genave Alpha 200B radio. Navigation lights.
Span (both): 26 ft 4 in (8.03 m)
Length: 19 ft 3 in (5.87 m)
Height: 7 ft 9 in (2.36 m)
Wing area: 210.38 sq.ft (19.54 sq.m)
Wing chord, constant (both): 4 ft 2 in (1.27 m)
Wing aspect ratio: 5.84
Tailplane span: 9 ft 3 in (2.82 m)
Wheel track: 6 ft 0 in (1.83 m)
Wheel base: 13 ft 3 in (4.04 m)
Propeller diameter: 6 ft 2 in (1.88 m)
Empty weight: 950 lb (431 kg)
Max takeoff weight: 1,600 lb (726 kg)
Wing loading: 7.61 lb/sq.ft (37.15 kg/sq.m)
Power loading: 13.91 lb/hp (6.31 kg/hp)
Cruise speed: 90 mph (145 kmh)
Stall speed: 45 mph (73 kmh)
Climb at sea level, pilot only: 900 ft (274 m)/min
Range: 280 mls (450 km)
The prototype of a new single-seat Kelly-DI was being constructed in 1986, but this was not completed. It was said to be powered by a 40 hp engine.
At Sun 'n Fun, held in Lakeland, Florida, in March 1987 was exhibited the new Kelly-DII, for which a complete kit (including all welded assemblies and engine) was marketed by Rogers Aircraft of Sanford, Florida. It retained the general appearance of the Kelly-D, except for the nose cowlings. Although it had smaller overall dimensions, was very much lighter and lower powered by a 40 hp Rotax503 two-cylinder two-stroke engine, it remained a full-size biplane for two adults. However, development was not continued."