Hawker Cygnet

Hawker Cygnet
Cygnet with the start number 14, as used in the flight competition in Lympne in 1924
Type:	Light aircraft
Design country:	United Kingdom
Manufacturer:	HG Hawker Engineering Company Ltd.
First flight:	1924
Number of pieces:	2

G-EBMB at the RAF Museum Cosford

The Hawker Cygnet was a biplane - light aircraft of the British manufacturer Hawker Engineering from the 1920s.

history

Sidney Camm , who had joined HG Hawker Engineering Company in 1923, designed the Cygnet as his first job with the new employer. Hawker's chief designer, George Carter, supervised the design work and gave Camm the maxim to follow the Sopwith Tabloid and its flight performance, while keeping the weight and engine power 50% lower. The Air Ministry announced on January 10, 1924 that it would have a price of 3000 engl. Pound for a competition of two-seater light aircraft. The engines were allowed to have a maximum displacement of 1100 cm³. As a result, a number of companies began to develop appropriate competition aircraft.

Hawker announced two Cygnets as his contribution a few weeks before the competition date in August 1924. Hawker was able to draw on the long experience with the predecessor company Sopwith regarding the construction of light fighters. The machine finally built weighed only 170 kg with a span of 8.54 m.

At the competition in Lympne, the Anzani-powered machine with starting number 14 and the pilot Fred Raynham competed. The other number 15 Cygnet with the Scorpion engine was flown by Squadron Leader Longton. A number of problems with both engines occurred on the first few flights; a cylinder head and, in another case, several valves had to be replaced. Nonetheless, Raynham and Longton finished third and fourth, respectively. Raynham also won £ 100 for best take-off and landing performance. The performances at the competition in Lympne were as follows:

• No. 14: (Longton), minimum speed reached: 43.95 mph, take-off distance: 269 yd., Landing distance: 66.7 yd., Flight time: 8 hours, distance: 400 mi
• No. 15: (Raynham), achieved minimum speed: 34.42 mph, take-off distance: 250 yd., Landing distance: 72.5 yd., Flight time: 10 hours 29 min., Distance: 437.5 mi

After the Lympne competition, both planes took part in the Grosvenor Challenge Race , where they had to give up in the early stages of the race. The Directorate of Technical Development then issued a report in which the Cygnet was, however, largely positive. Only the low ground clearance of the low chassis was complained about, and there was also the finding that the construction was not robust enough for the tough training operations.

Both machines received civil license plates shortly after the comparison flight, No. 14 received G-EBJH and No. 15 G-EBMB. Despite the difficulties with the Anzani engine, the G-EBJH returned to the Lympne meeting in August 1925, with pilot PWS Bulman winning the International Handicap Race with an average speed of over 100 mi of 75.6 mph.

For the Lympne Lightplane Meeting that took place in September 1926 , both aircraft received the tried and tested Bristol Cherub III engine. The propulsion problems could thus be resolved, so that over a distance of 1994 mi with a total flight time of 30 hours 41 minutes, an average of 64.9 mph could be achieved and the Daily Mail price over 3000 pounds was won with the pilot Bulman . After the competition, the machine was dismantled in front of an audience and it was shown that no important parts had to be replaced or repaired.

Whereabouts

The replica G-EBJI in the Shuttleworth Collection , Old Warden

The G-EBMB continued to be used in races until the certificate of airworthiness expired in March 1929 and then stored in Brooklands and virtually forgotten. It was not rediscovered until the late 1940s and Hawker restored it. The RAF Museum in Hendon received the aircraft as a gift in the 1970s and it was open to viewing at the Sidney Camm Memorial Hall . Today it is in the RAF Museum Cosford. The G-EBJH crashed on takeoff in November 1927 when attempting a non-stop flight from Lympne to Bucharest . There was no more reconstruction.

In the early 1990s, Don Cashmore created a faithful replica of the Cygnet, which flew for the first time in March 1993. As an homage to Sidney Camm, the machine was initially marked G-CAMM, then G-EBJI and is on display in the Shuttleworth Collection Old Warden ( Bedfordshire ).

construction

The cells of the two aircraft were identical, but two different engines were used. Both the British Anzani and the 34 hp two-cylinder ABC Scorpion engine were used.

The Cygnet was a single-handled biplane with staggered wings, with the upper wing being significantly larger. The hull was made up of four longerons , which were braced and braced diagonally. The sides and bottom of the fuselage were flat, and the upper part of the fuselage was rounded by shaped pieces. The wooden box spar of the wings was wrapped in fabric, the rear auxiliary spar was reinforced with screwed-on duralumin profiles. The connection between the two wings consisted of I-stems. Both wings had ailerons that spanned the entire span. The wings could be folded onto the fuselage. The fixed, very low landing gear had the rubber band dampers and spring units common in light aircraft at the time. The pendulum rudder (without the rudder fin) had the same structure as the wings.

During development, great importance was attached to the lowest possible weight, for example only a few metal fittings were used, so that when fully loaded the total weight was only 331 kg.

Technical specifications

Parameter	Data
crew	1
Passengers	1
length	6.18 m
span	8.54 m
height	1.78 m
Wing area	15.33 m²
Empty mass	169.3 kg (with Cherub engine)
Max. Takeoff mass	331.4 kg
Top speed	131 km / h
Engines	1 × Bristol Cherub III two-cylinder engine 34 PS (25 kW)

See also

• List of aircraft types

literature

• Francis K. Mason: Hawker Aircraft since 1920 . London: Putnam, 1991. ISBN 0-85177-839-9 , p. 108 ff.
• Richard Riding: British Pre-War Ultra-Lights Part 55 - Hawker Cygnet . In: Airplane Monthly October 1985, pp. 554 ff.
• Don Cashmore: Cashmore's Cygnet . In: Airplane Monthly September 1994, p. 8 ff.

Web links

Commons : Hawker Cygnet  - collection of images, videos and audio files

Individual evidence

1. ^ Don Cashmore: Airplane Monthly, September 1994, p. 8