Heinonen HK-1
| HK-1 | |
|---|---|
| |
| Role | Sport aircraft |
| National origin | Finland |
| Designer | Juhani Heinonen |
| First flight | August 1954 |
| Status | Sole example in the Finnish Aviation Museum |
| Number built | 3 |
The Heinonen HK-1 Keltiäinen[1] is a Finnish single-seat, single-engined sport aircraft of the 1950s. Three examples were built. The first was used by its designer to set a class distance record in 1957 that stood for 18 years before being beaten.
Design and development[edit]
Juhani Heinonen, an aeronautical engineer who had previously worked for the Valmet aircraft factory at Tampere, and then for Finnair, designed a single-seat, single engined aerobatic sport aircraft, the Heinonen HK-1. It was a low winged monoplane of all-wooden construction, powered by a Walter Mikron air-cooled inline engine rated at 48 kilowatts (65 hp) driving a two-bladed propeller. Split flaps were fitted to the wings, while the aircraft had a fixed tailwheel undercarriage, with a steerable tailwheel but no brakes. The pilot sat under a sliding perspex canopy.[2][3] A prototype was built at the glider school at Jämi,[4] first flying in August 1954.[2]
Operational history[edit]
The HK-1 was displayed at the 1955[5] and 1957 Ypenburg airshows.[6] On 10 July 1957, Heinonen flew the HK-1, fitted with an additional ventral fuel tank,[3] non-stop between Madrid, Spain and Turku in Finland, covering a distance of 2,844 kilometres (1,767 mi) in 17 hours 1 minute, setting a class world distance record for aircraft of less than 500 kilograms (1,100 lb) take-off weight.[7][8] For this flight, Heinonen was awarded a Louis Blériot medal by the Fédération Aéronautique Internationale.[9] This record was not broken until 2 July 1975.[10]
The aircraft is now preserved at the Finnish Aviation Museum near Helsinki Airport.[1]
Specifications[edit]
Data from Jane's All The World's Aircraft 1956–57[2]
General characteristics
- Crew: 1
- Length: 5.35 m (17 ft 7 in)
- Wingspan: 6.86 m (22 ft 6 in)
- Height: 2.08 m (6 ft 10 in)
- Wing area: 7.0 m2 (75 sq ft)
- Aspect ratio: 6.8:1
- Empty weight: 250 kg (551 lb)
- Gross weight: 400 kg (882 lb)
- Fuel capacity: 58 L (13 imp gal; 15 US gal)
- Powerplant: 1 × Walter Mikron III air-cooled inverted four-cylinder inline engine, 48 kW (65 hp)
Performance
- Maximum speed: 215 km/h (134 mph, 116 kn) at sea level
- Cruise speed: 185 km/h (115 mph, 100 kn)
- Range: 700 km (430 mi, 380 nmi)
- Rate of climb: 4.5 m/s (880 ft/min)
- Take-off distance to 15.25 m (50 ft): 240 m (790 ft)
- Landing distance from 15.25 m (50 ft): 350 metres (1,150 ft)
See also[edit]
Aircraft of comparable role, configuration, and era
Notes[edit]
- ^ a b "Heinonen HK-1 Keltiäinen" (in Finnish). Suomen Ilmailumuseo. Retrieved 12 July 2014.
- ^ a b c Bridgman 1956, p. 124.
- ^ a b Best-Devereux Flight 17 January 1958, p. 85.
- ^ Flight 17 June 1955, p. 846.
- ^ Flight 10 June 1955, p. 783.
- ^ Flight 21 June 1957, p. 829.
- ^ "FAI Record ID #1894". Fédération Aéronautique Internationale. Retrieved 12 July 2014.
- ^ Taylor 1962, p. 30.
- ^ Flight 30 May 1958, p. 727.
- ^ "Powered Aeroplanes World Records: C1a - Landplanes:take off weight 300 to 500 kg: Distance". Fédération Aéronautique Internationale. Archived from the original on 10 May 2016. Retrieved 12 July 2014.
References[edit]
- Best-Devereaux, H. (17 January 1958). "Ultra-Light Pot Pourri". Flight. Vol. 73, no. 2556. pp. 85–86. Archived from the original on 24 June 2015.
- Bridgman, Leonard (1956). Jane's All The World's Aircraft 1956–57. New York: The McGraw-Hill Book Company, Inc.
- "Club and Gliding News". Flight. Vol. 67, no. 2421. 17 June 1955. p. 846. Archived from the original on 6 March 2016.
- "From All Quarters: F.A.I. Awards". Flight. Vol. 73, no. 2575. 30 May 1958. p. 727. Archived from the original on 5 March 2016.
- "Ilsy 6: Brute Force and Elegance at the Ypenburg Show". Flight. Vol. 71, no. 2526. 21 June 1957. pp. 827–830.
- Taylor, John W. R. (1962). Jane's All The World's Aircraft 1962–63. London: Sampson Low, Marston & Company, Ltd.
- "Ypenburg Impressions". Flight. Vol. 67, no. 2420. 10 June 1955. p. 783. Archived from the original on 5 March 2016.