Engineering:Mráz Sokol
| M-1 Sokol | |
|---|---|
| |
| M-1C in the Prague Aviation Museum, Kbely | |
| Role | Utility aircraft |
| National origin | Czechoslovakia |
| Manufacturer | Beneš-Mráz, Choceň |
| Designer | Zdeněk Rublič |
| First flight | 9 March 1946 |
| Number built | 287 |
The Mráz M.1 Sokol (English: "Falcon") was a light aircraft built in Czechoslovakia in the years following the end of the Second World War. Designed in secret by Zdeněk Rublič at the Beneš-Mráz factory during the German occupation, the type was put into production in 1946.
Design and development
The Sokol was a conventional, low-wing monoplane that took the pre-war Beneš-Mráz Bibi as its starting point. Two seats were provided side-by-side in an enclosed cabin, and the main units of the tailwheel undercarriage were retractable. Construction throughout was of wood.[1]
The prototype, designated the M.1/1 and registered as OK-ZHA, first flew on 9 March 1946. After testing, the prototype was redesignated the M.1A, as the type entered production. A re-engined two-seater was built designated the M.1B with a 105 hp (78 kW) ZLAS Toma 4 engine, flying for the first time on 19 May 1946 but no more M.1Bs were built. Instead, the M.1A was modified by adding a third seat in the rear, becoming the M.1C and first flying on 16 February 1947. The M.1C became the main production variant with 183 aircraft built.[1]
In 1948 the M.1C was further developed as the M.1D with an enlarged single-piece canopy and a revised rudder. The M.1D first flew on 4 October 1948 and 104 were built. One M.1D was fitted with locally produced floats and re-designated the M.1E, it first flew in September 1949. A minor variant was the Para-Sokol which was fitted with rearward sliding canopy to allow parachutists to leave the aircraft.[2]
Around 287 aircraft were built but the deterioration of the Urea-based glue used caused many examples to be condemned in the early 1960s and withdrawn from use.[2] Nineteen Sokols were recorded as still being registered in 2013 with only a few still flyable.[3]
Variants
- M-1A – original two-seat version with Walter Minor engine
- M-1B – similar to M-1A but with ZLAS Toma 4 engine (1 built)[4]
- M-1C – revised version, with longer fuselage and third seat, and swept leading edges on wing (183 built)
- M-1D – similar to M-1C with new, single-piece canopy and larger rear windows (104 built)
- M-1E – similar to M-1D but equipped with pontoons (at least 1 built)
Operators
Czechoslovakia
- Czechoslovakian National Security Guard
Egypt
Surviving aircraft
An M-1C, registration G-AIXN is maintained in flyable condition in the UK and is based at Turweston Aerodrome[5] Other airworthy examples exist in the Czech Republic at Prague Točná Airport (2016) and in Germany (2012).
- M.1C OK-AHN is on display at the National Technical Museum, Prague, Czech Republic.
- M.1C OK-BHM is on display at the Prague Aviation Museum, Kbely, Czech Republic
- M.1C HA-REA is on display at the Hungarian Technical and Transportation Museum, Budapest, Hungary.
- M.1C 03 is on display at the Beijing Air and Space Museum (previously known as Beijing Aviation Museum), Beijing, China.
- M.1C 04 is on display at the Chinese Aviation Museum, Datangshan, China
Specifications (M-1D)
Data from Jane's All The World's Aircraft 1951–52 [6]
General characteristics
- Crew: 1
- Capacity: 2 passengers
- Length: 7.35 m (24 ft 1 in)
- Wingspan: 10.0 m (32 ft 10 in)
- Height: 2.20 m (7 ft 3 in) (tail up)
- Wing area: 13.8 m2 (149 sq ft)
- Empty weight: 425 kg (937 lb)
- Gross weight: 780 kg (1,720 lb)
- Powerplant: 1 × Walter Minor 4-III air-cooled four-cylinder inverted inline engine, 78 kW (105 hp)
Performance
- Maximum speed: 240 km/h (150 mph, 130 kn)
- Cruise speed: 212 km/h (132 mph, 114 kn)
- Range: 1,000 km (620 mi, 540 nmi)
- Service ceiling: 4,800 m (15,700 ft)
- Rate of climb: 3.0 m/s (590 ft/min)
See also
Related development
References
- ↑ 1.0 1.1 Air-Britain Archive September 2013, pp. 101, 103
- ↑ 2.0 2.1 Air-Britain Archive September 2013, p. 104
- ↑ Air-Britain Archive September 2013, p. 105
- ↑ Air-Britain Archive September 2013, p. 103
- ↑ "The last of the warm ones!" (in en-GB). AviatorUK. 2017-10-27. https://www.aviatoruk.ga/the-last-of-the-warm-ones/.
- ↑ Bridgman 1951, pp. 110c–111c.
- Bridgman, Leonard (1951). Jane's All The World's Aircraft 1951–52. London: Sampson Low, Marston & Company, Ltd..
- "Head-On View: No. 48: The Mraz M.1 Sokol". Air-Britain Archive: 106. September 2013. ISSN 0262-4923.
- Němeček, Václav (1968). Československá letadla. Prague: Naše Vojsko.
- Simpson, R. W. (1995). Airlife's General Aviation. Shrewsbury: Airlife Publishing.
- Taylor, Michael J. H. (1989). Jane's Encyclopedia of Aviation. London: Studio Editions. pp. 571.
- Rare Sokol M1C at Prague Točná Airport
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