Main Menu

Weedhopper of Utah JC-24 Weedhopper
Chotia Weedhopper

Ultra Systems Weedhopper

 

weedhopper

 

Designed by John Chotia and marketed in kit form by his company, Ultra Systems of PO Box 2253, Ogden, Utah, the Weedhopper is a powered hang glider envisaged as a low cost fun aeroplane that does away with the conventional hang glider's need for a hill and wind, and the bruises, hard landings and other exertions that usually accompany this form of flying. The Weedhopper is Chotia's 23rd design, following 18 hang gliders of both rigid and flex-wing types, and five powered gliders of which several are foot-launched.
 
Weedhopper of Utah was founded in 1977 by John Chotia, who asked Klaus Hill, creator of the Hummingbird, Hummer and the famous Fledgling, to design a minimum‑cost ultralight. His flying wing design was not particularly well accepted in its original form, but fitted with an empennage by John Chotia, it gave rise to one of the most popular of the early ultralights. This ultralight is perhaps the world’s simplest airplane.
 
It was designed from the start to take engine and landing gear loads, and has conventional rudder and elevator controls (but no ailerons) and proper seating for the pilot, who sits suspended under the wing just about on the cg position; this means that the design is not nearly so sensitive to pilot weight changes as other ultralights. The triangle undercarriage is mounted on the small platform-like structure on which the pilot sits, and has a steerable nosewheel. A rigid as distinct from flexible wing was chosen so as to retain control and stability in all attitudes, and the wings are of the 'roll up' kind, which can be dismantled easily for transport. The Weedhopper's structure is basically of aluminium tubing partially covered with dacron sailcloth, which simply bolts together for assembly, and is strong enough to lift a man weighing 200lb at an airfield elevation of 5,000ft. The engine is a 292cc Yamaha which produces 19hp at 5,000 rpm and is mounted just ahead of the wing leading edge on a tubular framework. An optional double-surfaced wing is available together with streamlined struts for pilots of over 190lb weight who wish to fly at airfield elevations of 4,000ft or more, especailly on warm days. The Weedhopper can be stalled safely and does about 30 miles to a gallon of fuel. It is one of a growing number of powered hang gliders and what are termed 'minimum aeroplanes' - ultra-lights of low power and a very simple and basic type of airframe which, unlike motor gliders, are not intended for soaring flight with the engine stopped.
Inspired by the Demoiselle 20 of Santos Dumont, John produced two prototypes and, after an elaborate test flying programme, two pre‑production aircraft in February 1978, followed in November 1979 by a new prototype, this time with a larger wing area.

 

The first production machines were known as the Weedhopper JC-24. Single-seat single-engined high-wing monoplane with two-axis control (three-axis option-al). Wing has swept back leading edge, swept forward trailing edge and tapering chord. cruciform tail. Pitch control by elevator on tail; yaw control by fully flying rudder with additional fin; no separate roll control (option-al roll control by spoilers); control inputs through stick for pitch/yaw (optional: pedals for roll). Wing braced from below by struts; wing profile; single-surface. Undercar-riage has three wheels in tricycle formation; no suspension on any wheels. Push-right go-left nosewheel steering independent from yaw control. Optional brake on nosewheel. Alumi-nium-tube framework, without pod. Engine mounted at wing height driving tractor prop-eller.

John Chotia planed to retain his original two-axis Weedhopper (with a retrofit, three-axis option) for the benefit M nonpilots. "They learn faster and have a much easier time of it with linked controls," says John. "You can't knock it.---The Weedhopper, which was available with three different wings (and which the Navy has purchased for testing) was conceived as a trainer, and consequently it's built like a tank, to withstand "refinements”.

The Weedhopper’s basic structure is of seamless, drawn 6061 aluminum tubing, reinforced at all attach points with larger tubing and/or wooden dowels. Premachined brackets or gussets are used to join the tubes. All bolts and hardware are of aircraft quality. Covering is 3.8-ounce stabilized Dacron sailcloth, presewn to slip into place, with no additional sew-ing, gluing or doping necessary. Designer John Chotia disliked the high rpm inefficiencies of snowmobile engines, so he designed his own powerplant, the Chotia 460, that delivers 18.5 hp at 3500 rpm to permit a direct-drive propeller. The Weedhopper has dispensed with any control sur-faces on the wing, relying on a rudder-induced yaw and wing dihedral to achieve a positive roll force and coordinated turns. Power-on stalls result in a loss of just 10-15 feet. Carry-ing 220 pounds, redline speed is 50 mph, and cruise is 30 mph. First year built 1974. Units delivered by June 1981 1,200.

In 1980 the full kit price was US$2995.

By 1981 the standard model was the Weedhopper JC-24B, often known simply as the Weedhopper B, which had a simpler structure than the original JC-24 and which could be fitted with spoilers to give three-axis control, two-axis being the standard arrangement. That year three new models were introduced. First came the Weedhopper JC-24C, often abbrevi-ated to Weedhopper C, which replaced the JC-24B and had a redesigned engine mount, a more striking finish with black anodised tubes and a more comfortable seat. Second came the JC-24BL Weedhopper Two, which de-spite its title was a single-seater. This soaring oriented machine had a larger span and area, a reinforced structure and spoilers, but was only ever distributed in a very small way. Thirdly was the company's two-seater, which took over the 'Two' part of the JC-24BL's title and was dubbed JC-31A Weedhopper Two. At first reserved for dealers, it was later sold openly but without great success.
The JC-24P Pen-guin was a clipped wing model with smaller area, designed not to fly! It was built for Weedhopper dealers to help with ground training. The Gypsy featured ailerons and a pod.
In 1983, the JC-24C with Chotia engine was the only model, sold as a kit requiring 40h assembly for $4095. Options include a soaring specification, developed from experience with the JC-24BL and using 3.0 ft (0. 91 m) wing tip extensions and spoil-ers, 16 inch (41 cm) wheels for $75, double -surface wing for $200, nosewheel brake for $35, and transport covers for $80.
The Weedhopper C is powered by a Chotia 460 two-stroke driving a Weedhopper-built, two-blade, fixed-pitch wooden propeller via direct drive. The engine is mounted in tractor posi-tion forward of the main wing. Fuel is carried in a rotational molded HDPE tank. LANDING GEAR: Tricycle-type with steerable nosewheel. The nosewheel is fitted with a brake, and all wheels are 11” in diameter. The gears are solid mounted.
Weedhopper model 40 2009 Price: US$7995

Weedhopper 40 Standard Features:
Steerable nose wheel
Nosewheel brake
Full front windshield
Instrument Package
Tachometer
Exhaust Gas Temperature Gauge
Cylinder Head Temperature Gauge
Airspeed Indicator
Construction Type: Aluminum tubing airframe with Polyester-Dacron sailcloth wing coverings.

weedhopper-40
Weedhopper Model 40


Weedhopper
Empty wt: 160 lbs
Gross weight 181 lbs
Max pilot weight 220 lbs
Wing span: 28 ft
Engine: Choita 460, 18.5 hp
Vne: 50 mph
Cruise: 30 mph

Weedhopper II

Wingspan, 34 ft
Wing area, 208 sq.ft
Aspect ratio, 5.67
Overall length, 18 ft
Empty weight 195 lbs
Usable payload (include fuel), 400 lbs
Wing loading, 2 lbs/sq.ft
L/D power-off glide ratio, 9.5:1
Cruise speed (85% power), 30 mph
Stall speed, 22 mph
Approach speed, 30 mph
Flair speed, 22 mph
Liftoff speed, 18-22 mph
Takeoff roll distance, 200 ft
Rate of climb, 250 fpm
Fuel capacity, 2 USgal
Range at cruise, 50 mi
Engine: Chotia 460, 456cc
Rated HP, 30 hp
Static thrust 140-150 lbs

Weedhopper DeLuxe
Speed max: 62 mph
Cruise: 50 mph
Range: 75 sm
Stall: 22 mph
ROC: 900 fpm
Take-off dist: 50 ft
Landing dist: 100 ft
Service ceiling: 10,000 ft
Engine: Rotax 447, 40 hp
Fuel cap: 5 USG
Weight empty: 252 lbs
Gross: 500 lbs
Height: 6.9 ft
Length: 18.25 ft
Wing span: 28 ft
Wing area: 168 sq.ft
Seats: 1
Landing gear: nose

Weedhopper C
Engine: Chotia 460D, 25 hp at 3700 rpm
Propeller diameter and pitch 44 x 19 inch, 1.11 x 0.48 m
No reduction
Power per unit area 0.14 hp/sq.ft, 1.6 hp/sq.m
Fuel capacity 3.5 US gal, 2.9 Imp gal, 13.2 litre
Length overall 18.5 ft, 5.64 m
Height overall 6.0ft, 1.83m
Wing span 28.0ft, 8.53m
Mean chord 6.0ft, 1.83m
Total wing area 168 sq.ft, 15.6 sq.m
Wing aspect ratio 4.7/1
Nosewheel diameter overall 11 inch, 28cm
Main wheels diameter overall 11 inch, 28 cm
Empty weight 160 lb, 73kg
Max take-off weight 380 lb, 172kg
Payload 220 lb, 100kg
Max wing loading 2.26 lb/sq.ft, 11.0kg/sq.m
Max power loading 15.2 lb/hp, 6.9kg/hp
Load factors; +5.0, -2.0 ultimate
Max level speed 50 mph, 80 kph
Max cruising speed 40mph, 64kph
Economic cruising speed 30 mph, 48 kph
Stalling speed 20 mph, 32 kph
Max climb rate at sea level 600 ft/min, 3.1 m/s
Min sink rate 350 ft/min, 1.7m/s
Best glide ratio with power off 7.3/1
Take-off distance 100ft, 30m
Landing distance 75ft, 23m
Service ceiling 10,000ft, 3050m
Range at average cruising speed 90 mile, 145 km

Weedhopper Standard
Cruise: 50 mph
Stall: 25 mph
Range: 120 sm
Rate of climb: 500 fpm
Takeoff dist: 150 ft
Landing dist: 150 ft
Engine: Rotax 277, 30 hp
Fuel capacity: 5 USG
Empty weight: 235 lb
Gross weight: 485 lb
Length: 17.4 ft
Wing span: 28 ft
Wing area: 168 sq.ft
Seats: 1
Landing gear: nosewheel
LSA: yes

Weedhopper Super

Cruise: 60 mph
Stall: 25 mph
Range: 100 sm
Rate of climb: 800 fpm
Takeoff dist: 150 ft
Landing dist: 150 ft
Engine: Rotax 503, 50 hp
Fuel capacity: 5 USG
Empty weight: 330 lb
Gross weight: 830 lb
Length: 18.6 ft
Wing span: 28 ft
Wing area: 168 sq.ft
Seats: 1
Landing gear: nosewheel
LSA: yes

Weedhopper 40
Engine: Rotax 447, 40 hp
Propeller: Ground Adjustable Composite Powerfin.
VNE: 56 kt / 65 mph / 105 kmh
Cruise: 50 mph
Stall: 17 kt / 20 mph / 32 kmh
Range: 120 sm
Rate of climb: 1000 fpm / 5 m/s
Take-off distance (50ft obstacle): 100 ft / 30 m
Landing distance (50ft obstacle): 100 ft / 30 m
Fuel capacity: 5 USG
Empty weight: 113 kg / 250 lb
Gross weight: 249 kg / 550 lb
Length: 18 ft 6 in
Wing span: 28 ft
Wing area: 168 sq.ft
Height: 6 ft. 9 in.
Seats: 1
Landing gear: nosewheel
Assembly time:25 to 30 hours
LSA: yes

 

 


Copyright © 2017 all-aero. All Rights Reserved.
Joomla! is Free Software released under the GNU General Public License.