Continuing development and improvements to the B10 design resulted in the B20 model. Requests kept flooding in to the factory for a two-seater version and it was not long before the B22 came on the scene. Sporting dual seats and controls. In 1985 the Micro Aviation NZ Ltd, B22 Bantam, made its successful maiden flight from the company’s Te Kowhai base – a two-place microlight. At the hands of Max Clear, co-founder of the company, the aircraft began a series of proving flights. The B22 model is aimed at the flight training market.

Basically a stretched version of the popular B20, the side-by-side two-seater incorporates a number of new design features including lift struts which replace the two outer flying wires to each wing. However whilst the two inner flying wires have been retained, gone is the familiar kingpost and associated landing wires. A redesigned empennage now means that fin and stabilizer are interchangable, reducing complexity and keeping construction cost down. These refinements were to be incorporated into all future production B20 models as well.

A redesigned wing, incorporating a higher lift aerofoil section, utilises similar construction techniques as the single seat Bantam but an increased span – now 32 feet – gives the B22 162 square feet of wing area – an increase of more than 10 percent. Full span flaperons have been retained. Power is supplied by the Austrian Rotax 503 with an integral gearbox driving a locally manufactured 62″ x 36” Perry prop. Fuel is contained in a 29 litre cylindrical aluminium tank (sufficient fuel for more than 2.5 hours of flying) designed and manufactured by John Smith, the other partner in this venture. Situated directly behind the seats, the tank has an external site gauge easily visible in flight. A wide fibreglass pod and windshield, designed by Micro Aviation and built by Ultralight Aircraft Manufacturing at Ardmore, provides protection while permitting excellent visibility.

Six B-22 Bantams were built, the first flying on 15 January 1986, and – after the paperwork had exceeded the weight of the B-22 Bantam and test pilots had flown a trouble free 150 hours – the type certificate came to hand.
Further impetus to the project was added by the constant stream of visitors to the Te Kowhai hangar, more than a few matching enthusiasm with orders. With a more powerful Rotax 582 engine, it became the standard production model in 1986. Twenty B-22s were completed during 1986; the 50th Bantam being completed shortly after Christmas 1986.

An agricultural spraying version was designated the B22AG.

When the Jabiru engine was first fitted to the B22 it was called the B22J Bantaroo, though this label was soon dropped. The B22J increased gross weight from 377kg to 430kg.

Not that development stopped here either, although all of the models were Type approved in New Zealand, it was found that in order to gain both International recognition and approval to use the aircraft as a trainer, called for the production of a fully Certified version.

As a result the factory geared itself up for this mammoth task. The wing was re-designed with a wider chord, shorter span and Clark-Y airfoil section, plus two more ribs. Changes were also made to the tail section, flaperons and cockpit, to name a few. The New Zealand Department of Civil Aviation supervised, tested and advised throughout this long drawn out process, finally awarding the new B22S full certification status in 1995.

Refinements made the vertical stabiliser and rudder interchangeable with the horizontal stabiliser and more eyebolts in the aileron and rudder and new instrument panel. With the introduction of the B22S in 1994, the serial sequence changed to year then number, at 94-001. The S suffix related to the British CAR regulation section S, including a fuel cock and a shortened fuel tank.

The Bantam B22S and B22J (with the new Jabiru 4-stroke engine) models are marketed in a number in a number of countries with in excess of 240 units having been produced. A paraplegic version with modified flght controls was also available.

Under development in 2009 was the B22UL powered by a ULPower UL260i engine with Full Authority Digital Engine Control, producing 71kW (95hp).

Gallery

Stall: 23 kt / 26 mph / 43 kmh
Cruise: 56 kt / 64 mph / 104 kmh
VNE: 80 kt / 92 mph / 148 kmh
Empty Weight: 176 kg / 388 lbs
MTOW Weight: 430 kg / 948 lbs
Glide Ratio: 7:1
Take-off distance (50ft obstacle): 100 ft / 30 m
Landing distance (50ft obstacle): 100 ft / 30 m

Engine: Rotax 503, 48 hp.
Wing span: 9.8m
Length: 5.5m
Empty wt: 144kg
MAUW: 356 kg
Max cruise: 104 kph
Range: 260km

Engine: Rotax 532, 64 hp.

Engine: Rotax 582, 63 hp
Wing span: 9.03 m
Wing area: 15.1 sq.m
MAUW: 378 kg
Empty weight: 176 kg
Fuel capacity: 40 lt
Max speed: 113 kph
Cruise speed: 105 kph
Minimum speed: 42 kph
Climb rate: 3.4 m/s
Certification: BCAR S
Seats: 2
Price (1998): £18,794

B22J
Engine: 4 cylinder Jabiru 2.2 lt.
Gross weight: 430kg

B22S
Engine: Rotax 582

B22UL
Engine: ULPower UL260i, 95 hp.

The B-10, too heavy for Class 1 microlight operation, was refined into the lighter B-20 with a new wing and tailplane section, less drag and a lighter engine. Refinements to the B10 design included pull-on sailcloth and fabricated ribs, resulting in the B20 designation. Appearing much trimmer and performing as well, if not better, than the heavier and more elaborate B-10 Bantam. First flown on 23 December, the B-20 was designed specifically to a lower empty weight in order to meet the microlight philosophy of a very basic flying machine. The result was a Bantam with somewhat better performance than the B-10 and the only penalty being a smaller fuel tank with consequently less endurance. The geared Rotax fitted to the B-20 is much quieter than the belt driven version fitted to the B-10, one B-10 owner has already made the conversion to a geared engine.
Designed by the Max Clear and John Smith design team at Te Kowhai, the B-20 has replaced the B-10 on the production line. The first production B-20 (s/n 0015) was delivered south by pilot Otto Gram to the South Island’s West Coast in early February. After a production run of 17 were built during 1985, the B-20 itself was superseded by the B-22. Two were exported to Australia. There were minor differences, the most significant being the “flaperons” which enhanced an already excellent take-off performance with a reduced approach speed. Conventional 3-axis controls.

Whereas the B 10 was an individually constructed (or at least individually finished) aircraft, the B 20 was the built as the start of the assembly line at Micro Aviation at Te Kowhai.

The B 20 had the same basic airframe as the B 10 but with a differently shaped pod and without the drooped wingtips. It had a tapered wing and a different airfoil to the B 10. It also had pre-sewn covers for the flying surfaces (whereas the B 10 had ceconite fabric glued to the airframe). Original examples had a Rotax 447 engine. 15 Bantam B 20s were made at Te Kowhai before production geared up with Micro Aviation producing the two seat Bantam B 22.

Whereas the B 10 was an individually constructed (or at least individually finished) aircraft, the B 20 was the built as the start of the assembly line at Micro Aviation at Te Kowhai.

The B 20 had the same basic airframe as the B 10 but with a differently shaped pod and without the drooped wingtips. It had a tapered wing and a different airfoil to the B 10. It also had pre-sewn covers for the flying surfaces (whereas the B 10 had ceconite fabric glued to the airframe). Original examples had a Rotax 447 engine. 15 Bantam B 20s were made at Te Kowhai before production geared up with Micro Aviation producing the two seat Bantam B 22.

Engine: Rotax 447, 40 hp.
Wing span: 8.69m.
Length: 5.15m.
Empty wt: 114 kg.
MAUW: 250 kg.
Max cruise: 93 kph.
Range: 170 km.

Of all metal construction, the Pulsar III’s use of an aerofoil section for the leading edge spar plus round-out improved its speed range and low-end performance.

Pulsar III
Engine: Rotax 582, 64 hp
Wing span: 9.2 m
Wing area: 15 sq.m
MAUW: 450 kg
Empty weight: 146 kg
Fuel capacity: 60 lt
Max speed: 160 kph
Cruise speed: 130 kph
Minimum speed: 50 kph
Climb rate: 6 m/s
Fuel consumption: 10 lt/hr
Certification: Espagnole
Seats: 2
Price (1998): 135 000 Fttc
Kit price (1998): 71 900 Fttc

Side by side two seat single engined high-wing monoplane with conventional three axis control. Wing has swept back leading and trailing edges, and tapering chord; no tail. Pitch/roll control by stabilators; yaw control by tip rudders; control inputs through stick for pitch/roll and pedals for yaw. Cantilever wing; wing profile NACA 23015; double-surface. Undercarriage has three wheels in tricycle formation; suspension on all wheels. Push right go right nosewheel steering connected to yaw control. Brake on nosewheel. Aluminium tube/wood/steel tube framework, partially enclosed. Engine mounted below wing driving pusher propeller.
Seeing the need for training aircraft, Micro Aviation decided at the end of 1981 to launch some two seater microlights. To this end, the firm asked Don Mitchell to give it the benefit of his experience in this matter and a prototype called the Two Seat Trainer was duly shown at Oshkosh in August 1982.
By 1983 it has not gone into serious production. The aircraft shown was a direct development of the B10 Mitchell Wing, enlarged and strengthened. It was intended that the two-seater should use a Konig SD570 four cylinder two stroke engine.

Engine: Konig SD570, 28 bhp at 4200 rpm.
Power per unit area 0.16hp/sq.ft, 1.7 hp/sq.m.
Wing span 38.0 ft, 11.58 m.
Mean chord 4.8 ft, 1.45 m.
Total wing area 181 sq.ft, 16.8 sq.m.
Wing aspect ratio 8.0/1.
Empty weight 240 lb, 109kg.
Max take off weight 640 lb, 290 kg.
Payload 400 lb, 181 kg.
Max wing loading 3.55 lb/sq.ft, 17.3 kg/sq.m.
Max power loading 22.9 lb/hp, 10.4kg/hp.
Load factors +6.0, 6.0 design.
Stalling speed 24 mph, 38 kph.
Max climb rate at sea level 400ft/min, 2.0m/s.
Take off distance 350ft, 107m.