Photograph:
Broadsmith-Ross Bett Biplane at Mascot, NSW in 1924 (Harry Broadsmith)
Country of origin:
Australia
Description:
Single-seat light biplane
Power Plant:
One 19 kw (25 hp) [1,067 cc] Anzani two-cylinder air-cooled engine
Specifications:
- Wingspan: 6.7 m (22 ft)
- Length: 5.18 m (17 ft)
- Wing area: 13.09 m² (141 sq ft)
- Max speed: 113 km/h (70 mph)
- Max altitude: 914 m (3,000 ft)
- Empty weight: 171 kg (376 lb)
- Loaded weight: 254 kg (561 lb)
History:
One of the aeroplanes designed and built for the low-powered aeroplane competition at Richmond, NSW in November/December 1924, the Broadsmith-Ross Bett I Biplane, also known as the Broadsmith B.2, was designed by well known aviation identity of the time, Mr Harry E Broadsmith who, for a period, had some association with A V Roe & Co.
The aircraft was built by Messrs Ross and Broadsmith, the latter mainly providing supervision, with the assistance of three of the employees of The Experimental Air Station at Botany, Broadsmith’s home being used as the main workshop, the living room being used for the fuselage, tail units and parts of the wing spars and ribs. The wings were assembled in a garage and less than thirteen weeks of evenings and weekends were used to build the B.2 and B.4.
The Bett was an equal span cantilever biplane, the upper wings being mounted on centre-section struts, the lower wings being mounted in the manner of a low-wing semi-cantilever monoplane. The wings were of conventional wooden construction with fabric covering, and were braced.
This aircraft was tested at some length during the program, and take-off and climb were found to be good. In the air it was said to handle like a “Sopwith Camel” or a “Pup Scout”. The cockpit was roomy, and the aircraft was of solid construction. However, the Anzani engine was found to produce a considerable amount of vibration and was very unreliable. The official report stated that “had the engine stood up to the job it would probably have taken off every prize at the meeting…” In the competition the Broadsmith-Ross Bett biplane won prize money totalling £200 ($400) for the best speed.
A further machine, known as the Bett monoplane, was also designed and built by the same team but was not completed in time for the meeting. It was also fitted with an Anzani engine, had an empty weight of 152 kg (336 lb), a loaded weight of 236 kg (521 lb), a length of 5.48 m (18 ft) and a wingspan of 6.06 m (19 ft 9 in).