In 1929, the Monospar Company Ltd was formed to pursue new techniques of designing cantilever wings, based on the work of Swiss engineer Helmuth J. Stieger, who headed the company. Helmuth John Stieger was born in Zurich in 1902, and educated at the Swiss Federal Polytechnic, and then at the Imperial College of Science in London. While working as a designer for William Beardmore and Company, he formed his own ideas about wing design, and evolved an improved method of building and stressing wings, for which he was later granted a British Patent in December 1927. The principle behind this Patent No. 306,220 was that the wing needed only one spar with torsion loads resisted by an efficient system of strong compression struts, with triangulated bracing in the form of thin wires. The design was revolutionary and very light for its strength.[1]
Based on this design, The Monospar Company designed a twin-engined low-wing aircraft designated the Monospar ST-3, that was built and flown in 1931 by the Gloster Aircraft Company at Brockworth, Gloucestershire. After successful testing of the Monospar ST-3, a new company General Aircraft Ltd was formed to produce aircraft that used the patented Monospar wing designs.[2]
The first production design was the Monospar ST-4, a twin-engined low-wing monoplane with a fixed tailwheel landing gear and folding wings for ground storage.[3] Powered by two Pobjoy R radial engines, the first aircraft (G-ABUZ) first flew in May 1932, and was followed by five production aircraft. The Monospar ST-4 Mk.II, an improved variant with minor differences, followed with a production run of 30. In 1933, the Monospar ST-6 appeared, a similar aircraft to the ST-4, with manually retractable landing gear and room for an extra passenger. The Monospar ST-6 was only the second British aircraft to fly with retractable landing gear (the first, the Airspeed Courier, was flown a few weeks earlier). Another Monospar ST-6 was built, and two ST-4 Mk.IIs were converted. GAL then produced a developed version, the Monospar ST-10, externally the same but powered by two Pobjoy Niagara engines, an improved fuel system, and aerodynamic refinements.[2][4] The Monospar ST-11 was developed from the ST-10, with retractable landing gear, and two were built for export to Australia.[1][5][6] A production batch of ten Monospar ST-12 aircraft was based on the ST-11, but with de Havilland Gipsy Major engines and fixed landing gear.[1]
Monospar ST-10 3 view from l'Aerophile magazine, January 1933
Data fromThe Illustrated Encyclopedia of Aircraft[12]
General characteristics
Capacity: four
Length: 26 ft 4 in (8.03 m)
Wingspan: 40 ft 2 in (12.24 m)
Height: 7 ft 10 in (2.30 m)
Wing area: 217 sq ft (20.16 m2)
Empty weight: 1,840 lb (835 kg)
Gross weight: 2,875 lb (1,304 kg)
Powerplant: 2 × de Havilland Gipsy Major 4-cylinder inverted inline piston engine , 130 hp (97 kW) each
Performance
Maximum speed: 158 mph (254 km/h, 137 kn)
Range: 410 mi (660 km, 360 nmi)
Service ceiling: 21,000 ft (6,400 m)
Incidentsedit
On 6 September 1935, a Monospar ST-12 operated by Australian Transcontinental Airways suffered engine failure, and made an emergency landing on Woodgreen Station in the Northern Territory. Reports vary slightly,[13] but the plane was said to be carrying the pilot J. Maher, with two passengers, Renfrey and Maloney, and a young crocodile that was being transported to Adelaide.[b] Renfrey walked for two days towards Ryan's Well, a watering hole on the Overland Telegraph Line around 40 mi (64 km), to seek assistance. Three men (one of several search parties sent out to look for the men[14]) motoring across the desert found him, and took him to Aileron telegraph station. In the meantime, Don Thomas from Alice Springs drove to Woodgreen to pick up Purvis Sr and two "blackfellows", one of whom managed to track down the plane based on the description of the location given by Renfrey. Maher and Maloney had only six oranges between them for food, but they survived until they were rescued by shooting and eating the crocodile.[15]
^ATA was a short-lived airline registered in Melbourne in 1935 by Harold Berryman, of Ballarat, and four other directors. Its three aeroplanes did the mail run from Darwin to Adelaide, Melbourne and Sydney, until it ceased operations in 1936 owing to the impossibility of importing more planes from Germany at that time.[11]
^Priest, Joan. Virtue in Flying 1975 Angus & Robertson ISBN0-207-13230-5
^Grey, C.G., ed. (1931). Jane's all the World's Aircraft 1931. London: Sampson Low, Marston & company, ltd. pp. 35c–36c.
^Bentley, Amanda (10 September 2019). "Major Harold John Thomas Berryman". Ballarat & District in the Great War. Retrieved 31 October 2022.
^The Illustrated Encyclopedia of Aircraft, p. 1938.
^ ab"Woodgreen Station". Bureau of Aircraft Accidents Archives. Retrieved 31 October 2022.
^"Mishap to Monospar 'plane". Western Argus. Vol. 41, no. 2361. Western Australia. 17 September 1935. p. 2. Retrieved 31 October 2022 – via National Library of Australia.
^"A Monospar down". The Macleay Chronicle. No. 2951. New South Wales, Australia. 11 September 1935. p. 4. Retrieved 31 October 2022 – via National Library of Australia.
Bibliographyedit
The Illustrated Encyclopedia of Aircraft (Part Work 1982–1985). Orbis Publishing, 1985, p. 2158.
Jackson, A.J. 1973. British Civil Aircraft since 1919, Volume 2. Putnam ISBN0-370-10010-7.
Lewis, Peter. 1971. British Racing and Record-Breaking Aircraft. Putnam ISBN0-370-00067-6
Ord-Hume, Arthur W. J. G. (2013) The Monospar, from tailless gliders to vast transport: the story of General Aircraft Ltd of Hanworth. Catrine, Ayrshire: Stenlake Publishing. ISBN9781840336368
Sherwood, Tim. 1999. Coming in to Land: A Short History of Hounslow, Hanworth and Heston Aerodromes 1911–1946. Heritage Publications (Hounslow Library) ISBN1-899144-30-7
Stroud, John. Wings of Peace, Aeroplane Monthly, April 1988
October 28, 2023
general, aircraft, monospar, 1930s, british, family, touring, utility, aircraft, built, general, aircraft, monospar, seriesgal, monospar, acts, hatfield, july, 1934, winning, king, racerole, cabin, monoplanemanufacturer, general, aircraft, ltdfirst, flight, 19. The General Aircraft Monospar was a 1930s British family of touring and utility aircraft built by General Aircraft Ltd GAL Monospar seriesGAL Monospar ST 10 G ACTS Hatfield 14 July 1934 winning the King s Cup Air RaceRole Cabin monoplaneManufacturer General Aircraft LtdFirst flight 1932Number built 45Variants Monospar ST 25 Contents 1 Design and development 2 Operational history 3 Variants 4 Operators 4 1 Civil operators 5 Survivors 6 Specifications Monospar ST 12 7 Incidents 8 See also 9 Footnotes 10 References 10 1 Notes 10 2 BibliographyDesign and development editIn 1929 the Monospar Company Ltd was formed to pursue new techniques of designing cantilever wings based on the work of Swiss engineer Helmuth J Stieger who headed the company Helmuth John Stieger was born in Zurich in 1902 and educated at the Swiss Federal Polytechnic and then at the Imperial College of Science in London While working as a designer for William Beardmore and Company he formed his own ideas about wing design and evolved an improved method of building and stressing wings for which he was later granted a British Patent in December 1927 The principle behind this Patent No 306 220 was that the wing needed only one spar with torsion loads resisted by an efficient system of strong compression struts with triangulated bracing in the form of thin wires The design was revolutionary and very light for its strength 1 Based on this design The Monospar Company designed a twin engined low wing aircraft designated the Monospar ST 3 that was built and flown in 1931 by the Gloster Aircraft Company at Brockworth Gloucestershire After successful testing of the Monospar ST 3 a new company General Aircraft Ltd was formed to produce aircraft that used the patented Monospar wing designs 2 The first production design was the Monospar ST 4 a twin engined low wing monoplane with a fixed tailwheel landing gear and folding wings for ground storage 3 Powered by two Pobjoy R radial engines the first aircraft G ABUZ first flew in May 1932 and was followed by five production aircraft The Monospar ST 4 Mk II an improved variant with minor differences followed with a production run of 30 In 1933 the Monospar ST 6 appeared a similar aircraft to the ST 4 with manually retractable landing gear and room for an extra passenger The Monospar ST 6 was only the second British aircraft to fly with retractable landing gear the first the Airspeed Courier was flown a few weeks earlier Another Monospar ST 6 was built and two ST 4 Mk IIs were converted GAL then produced a developed version the Monospar ST 10 externally the same but powered by two Pobjoy Niagara engines an improved fuel system and aerodynamic refinements 2 4 The Monospar ST 11 was developed from the ST 10 with retractable landing gear and two were built for export to Australia 1 5 6 A production batch of ten Monospar ST 12 aircraft was based on the ST 11 but with de Havilland Gipsy Major engines and fixed landing gear 1 The Croydon factory closed down in 1934 and a larger factory was opened in 1935 at London Air Park Hanworth 7 Operational history editThe Monospar ST 10 prototype G ACTS won the 1934 King s Cup Air Race with an average speed of 134 16 mph 8 Only one other ST 10 was built 1 9 Variants edit nbsp GAL Monospar ST 4Monospar ST 3 Experimental cantilever monoplane powered by two 45 hp 34 kW British Salmson AD 9 engines one built 10 Monospar ST 4 Cantilever touring monoplane powered by two 85 hp 63 kW Pobjoy R radial engines seven built Monospar ST 4 Mk II Improved variant of Monospar ST 4 22 built two later converted to ST 6 standard Monospar ST 6 As Monospar ST 4 with manual retractable landing gear two built plus two conversions from ST 4 Mk IIs nbsp GAL Monospar ST 11 VH USN with pilots Collins and Wylie after flight from UK to Australia February 1935Monospar ST 10 Improved variant with two 90 hp 67 kW Pobjoy Niagara engines two built Monospar ST 11 Development of Monospar ST 10 with retractable landing gear two built Monospar ST 12 Fixed landing gear variant with two de Havilland Gipsy Major engines ten built General Aircraft ST 18 Croydon Ten seat transport with two Pratt and Whitney Wasp Junior engines one built Monospar ST 25 series Development of Monospar ST 10Operators edit nbsp PortugalPortuguese Navy nbsp South AfricaSouth African Air Force nbsp Spanish RepublicSpanish Republican Air Force 1936 from LAPE nbsp SpainSpanish Air Force nbsp TurkeyTurkish Air ForceCivil operators edit nbsp AustraliaAustralian Transcontinental Airways ATA 1935 1936 a nbsp BrazilVASP 1933 1938 nbsp United KingdomInner Circle Air Lines 1935 1935Survivors editOne Monospar ST 12 registration VH UTH is on display at the Newark Air Museum EnglandSpecifications Monospar ST 12 edit nbsp Monospar ST 10 3 view from l Aerophile magazine January 1933Data from The Illustrated Encyclopedia of Aircraft 12 General characteristicsCapacity four Length 26 ft 4 in 8 03 m Wingspan 40 ft 2 in 12 24 m Height 7 ft 10 in 2 30 m Wing area 217 sq ft 20 16 m2 Empty weight 1 840 lb 835 kg Gross weight 2 875 lb 1 304 kg Powerplant 2 de Havilland Gipsy Major 4 cylinder inverted inline piston engine 130 hp 97 kW eachPerformance Maximum speed 158 mph 254 km h 137 kn Range 410 mi 660 km 360 nmi Service ceiling 21 000 ft 6 400 m Incidents editOn 6 September 1935 a Monospar ST 12 operated by Australian Transcontinental Airways suffered engine failure and made an emergency landing on Woodgreen Station in the Northern Territory Reports vary slightly 13 but the plane was said to be carrying the pilot J Maher with two passengers Renfrey and Maloney and a young crocodile that was being transported to Adelaide b Renfrey walked for two days towards Ryan s Well a watering hole on the Overland Telegraph Line around 40 mi 64 km to seek assistance Three men one of several search parties sent out to look for the men 14 motoring across the desert found him and took him to Aileron telegraph station In the meantime Don Thomas from Alice Springs drove to Woodgreen to pick up Purvis Sr and two blackfellows one of whom managed to track down the plane based on the description of the location given by Renfrey Maher and Maloney had only six oranges between them for food but they survived until they were rescued by shooting and eating the crocodile 15 See also editGeneral Aircraft ST 18 CroydonRelated lists List of Interwar military aircraft List of aircraft of the Spanish Republican Air ForceFootnotes edit ATA was a short lived airline registered in Melbourne in 1935 by Harold Berryman of Ballarat and four other directors Its three aeroplanes did the mail run from Darwin to Adelaide Melbourne and Sydney until it ceased operations in 1936 owing to the impossibility of importing more planes from Germany at that time 11 One later report says the destination was Melbourne Zoo 13 References edit nbsp Wikimedia Commons has media related to General Aircraft Monospar Notes edit a b c d Ord Hume 2013 The Monospar a b Jackson 1973 pp 208 214 New British Plane Has Hinged Wings Popular Science November 1932 photos showing wings folded Sherwood 1999 Goodall Geoff General Aircraft Monospar in Australia www goodall com au Retrieved 13 June 2022 Priest Joan Virtue in Flying 1975 Angus amp Robertson ISBN 0 207 13230 5 Stroud May 1988 Lewis 1971 p 262 Priest Joan Virtue in Flying 1975 Angus amp Robertson ISBN 0 207 13230 5 Grey C G ed 1931 Jane s all the World s Aircraft 1931 London Sampson Low Marston amp company ltd pp 35c 36c Bentley Amanda 10 September 2019 Major Harold John Thomas Berryman Ballarat amp District in the Great War Retrieved 31 October 2022 The Illustrated Encyclopedia of Aircraft p 1938 a b Woodgreen Station Bureau of Aircraft Accidents Archives Retrieved 31 October 2022 Mishap to Monospar plane Western Argus Vol 41 no 2361 Western Australia 17 September 1935 p 2 Retrieved 31 October 2022 via National Library of Australia A Monospar down The Macleay Chronicle No 2951 New South Wales Australia 11 September 1935 p 4 Retrieved 31 October 2022 via National Library of Australia Bibliography edit The Illustrated Encyclopedia of Aircraft Part Work 1982 1985 Orbis Publishing 1985 p 2158 Jackson A J 1973 British Civil Aircraft since 1919 Volume 2 Putnam ISBN 0 370 10010 7 Lewis Peter 1971 British Racing and Record Breaking Aircraft Putnam ISBN 0 370 00067 6 Ord Hume Arthur W J G 2013 The Monospar from tailless gliders to vast transport the story of General Aircraft Ltd of Hanworth Catrine Ayrshire Stenlake Publishing ISBN 9781840336368 Sherwood Tim 1999 Coming in to Land A Short History of Hounslow Hanworth and Heston Aerodromes 1911 1946 Heritage Publications Hounslow Library ISBN 1 899144 30 7 Stroud John Wings of Peace Aeroplane Monthly April 1988 Retrieved from https en wikipedia org w index php title General Aircraft Monospar amp oldid 1145169475, wikipedia, wiki, book, books, library,
