Single seat single engined biplane with conventional three axis control. Wings have un¬swept leading and trailing edges, and constant chord, conventional tail. Pitch control by elevator on tail; yaw control by fin mounted rudder; roll control by full span ailerons on each wing; control inputs through stick for pitch/roll and bar for yaw. Wing braced by struts, and transverse X cables; wing profile Hovey 10; double surface. Tail surfaces of plywood-reinforced foam core. Undercarriage has three wheels in tail dragger formation. Fiberglass-covered laminated fir suspension on main wheels. Push right go right tailwheel steering connected to yaw control. Mahogany plywood closed-box fuselage, without pod, 3” aluminum tube tail boom foam filled for stiffness. Fuselage accommodates seat, rudder bar, standard controls and wing spar sockets. Engine mounted between wings driving pusher propeller.
Bob Hovey started to design the Whing Ding in October 1970 and at the same time he started to build the prototype. The result was that it accomplished its first flight in February 1971, only five months later.

Hovey Whing-Ding Article

Bob’s objective was to design a single seater which was easy to build in minimum time, offering the qualities of a STOL aircraft (short take off and landing), and quickly demountable to fit on to its specially designed road trailer. This 15-hp, 300-pound gross-weight biplane is the ultimate in lightness and simplicity. The tail surfaces are constructed from ½-inch thick Styrofoam art-board faced with high strength kraft paper on both sides, with the critical areas reinforced with 1/8-inch plywood gussets. The tail boom is a 3-inch aluminum pipe filled with foam to resist buckling. The fuselage is basically a 6-inch wide box of plywood filled with foam that serves as an engine mount and a mast support for the wings. The prop is belt-driven from a 15-hp McCulloch two-cycle go-kart engine. The wings have two spars and are fabric covered. The prototype established a record for light aircraft, with an empty weight of less than 121 lb (55 kg), but its designer had to abandon the original design of the tail structure which was made from polyurethane foam covered in kraft paper.
The wing section is an in house design, the Hovey 10, and the two wings are of equal span, staggered by 4O and having 1 O of dihedral. Their structure is a twin spar design in wood, using tubular metal ribs and with a polyurethane foam leading edge, the covering being fabric. The fuselage has a pine frame with mahogany plywood cladding and is filled with polyurethane foam. The pilot sits in front in the open air and leans back on a pylon which joins the two wings and also carries engine. The wings on each side are joined by two straight struts and rigged with two flying and landing wires in an X configuration on each half wing. Construction of the Ding requires around 400 hr.

Engine: McCulloch MC-¬101AA, 12.5 hp at 8000 rpm.
Propeller diameter 48 inch, 1.22m.
No reduction.
Power per unit area 0.13 hp/sq.ft, 1.4 hp/sq.m.
Fuel capacity 0.5 US gal, 0.4 Imp gal, 2.0 litre.
Length overall 13.0 ft, 3.96 m.
Height overall 5.33ft, 1.62m.
Wing span 17.0ft, 5.18m.
Dihedral 1 deg.
Sweepback 0 deg.
Total wing area 98 sq.ft, 9.1sq.m.
Wing aspect ratio 2.9/1.
Empty weight 122 lb, 55kg.
Max take off weight 310 lb, 140kg.
Payload 188 lb, 85kg.
Max wing loading 3.16 lb/sq.ft, 15.4kg/sq.m.
Max power loading 24.8 lb/hp, 11.2kg/hp.
Max level speed 50mph, 80kph.
Never exceed speed 60mph, 97 kph.
Max cruising speed 40 mph, 64 kph.
Stalling speed 26 mph, 42 kph.
Max climb rate at sea level 100ft/min, 0.5m/s.
Take off distance 250 ft, 75 m.
Landing distance 150 ft, 45 m.
Service ceiling 4000 ft, 1220 m.
Range at average cruising speed 20 mile, 32 km.

Hp range: 8-15
Length: 13 ft
Wingspan: 17 ft
Wingarea: 98 sq.ft
Empty weight: 122 lb
Gross weight; 310 lb
Fuel capacity: 1 USG
Top speed: 45 mph
Cruise: 35 mph
Stall: 28 mph
Range: 28 nm
ROC: 200 fpm
TO dist: 250 ft
Landing dist: 100 ft
Service ceiling: 2000 ft
Seats: 1
Landing gear: tailwheel

Engine: McCulloch, 12 hp
Hp range: 8-15
Length: 13 ft
Wingspan: 17 ft
Wingarea: 98 sq.ft
Empty weight: 123 lb
Gross weight: 310 lb
Fuel capacity: 3 USG
Cruise: 35 mph
Stall: 24 mph
ROC: 200 fpm
TO dist: 250 ft
Landing dist: 100 ft
Seats: 1
Landing gear: tailwheel
LSA: yes

The Delta Hawk is all pop-riveted aluminum tube construction covered with light weight dacron. Full span aileron with three-axis controls.

In 1984 the 40 hp Hovey Delta Hawk was sold as plans, $80, plans plus material kit, or fully assembled for $9250.

Gallery

Gross Wt. 446 lb.
Empty Wt. 248 lb.
Fuel capaci¬ty 3 USG.
Wingspan 24ft.
Engine Kawasaki 440
Reduction 2.25/1.
Cruise 45 mph.
Stall 27 mph.
Climb rate 700 ft

Single seat single engined biplane with conventional three axis control. Wing has unswept leading and trailing edges, and constant chord; conventional tall. Pitch control by elevator on tail; yaw control by fin mounted rudder; roll control by full span ailerons on upper wing; control inputs through stick for pitch/roll and pedals for yaw. Wing braced by struts and transverse X cables; wing profile; double surface. Undercarriage has three wheels in tail dragger formation. Push right go right tailwheel steering connected to yaw control. Aluminium tube framework, without pod. Engine mounted between wings driving tractor propeller. Tubing from 6061T6 aluminium; galvanised steel rigging; Dacron wing covering.

This three axis machine is a biplane which was revealed to the public at the EAA convention for amateur constructors, Oshkosh, in August 1982, where it was hailed as a modernised version of the Whing Ding II with a simpler structure and more power. The adoption of an aluminium tubular structure allowed Aircraft Specialties to offer the Delta Bird in plan form, as with the other two aircraft, but also as a kit requiring around 200 h for assembly. In place of the pusher common to the Beta Bird and the Whing Ding II, the motor is mounted as a tractor on a triangular framework at the front of the main framework. The exhaust pipe passes under this triangular section and finishes by the junction of the two triangular frameworks which support the main wheels, an arrangement designed to allow all terrain use. The machine retains conventional controls with ailerons on the trailing edges of the two top wings, a rudder hinging from the fin and the elevators from the horizontal stabiliser; they are all of generous proportions.

Engine: Cuyuna 430R, 30 hp at 5500 rpm.
Propeller diameter and pitch 54 x 27 inch, 1.37 x 0.69 m.
Belt reduction, ratio 2.0/1.
Power per unit area 0.20 hp/sq.ft, 2.1 hp/sq.m.
Fuel capacity 3.5 US gal, 2.9 Imp gal, 13.2 litre.
Length overall 15.0 ft, 4.57 m.
Height overall 6.0ft, 1.83m.
Wing span 24.0ft, 7.31m.
Constant chord 3.5 ft, 1.07 m.
Sweepback 0 deg.
Tailplane span 8.0 ft, 2.44 m.
Fin height 3.7 ft, 1.13 m.
Total wing area 152 sq.ft, 14.1 sq.m.
Fin area 9.0 sq.ft, 0.84sq.m .
Tailplane area 20.0 sq.ft, 1.86 sq.m.
Wing aspect ratio 6.9/1.
Wheel track 6.3ft, 1.92 m.
Main wheels diameter overall 15 inch, 39 cm.
Empty weight 218 lb, 99kg.
Max take off weight 450 lb, 204kg.
Payload 232 lb, 105 kg.
Max wing loading 2.96 lb/sq.ft, 14.5 kg/sq.m.
Max power loading 15.0 lb/hp, 6.8kg/hp.
Load factors +3.5, 3.5 design; +5.3, 5.3 ulti¬mate.
Max level speed 60mph, 97kph.
Never exceed speed 60mph, 97kph.
Max cruising speed 45mph, 72kph.
Stalling speed 26 mph, 42 kph.
Max climb rate at sea level 400 ft/min, 2.0 m/s.
Best glide ratio with power off 6/1.
Take off distance 250 ft, 75 m.
Landing distance 250 ft, 75 m.
Range at average cruising speed 50 mile, 80km.