Avia BH-33

Last updated
BH-33
Avia BH-33.jpg
General information
TypeFighter
Manufacturer Avia, PWS (under licence), Ikarus (under licence)
Designer
Primary users Czechoslovak Air Force
History
ManufacturedCa. 110, plus 50 licence-built in Poland and 22 in Yugoslavia
First flight21 October 1927
Developed from Avia BH-21
Avia BH-33 with engine Walter-Jupiter 480-600 HP Avia BH-33 1.jpg
Avia BH-33 with engine Walter-Jupiter 480–600 HP

The Avia BH-33 was a biplane fighter aircraft built in Czechoslovakia in 1927. It was based on the BH-21J which demonstrated promising results by combining the original BH-21 airframe with a licence-built Bristol Jupiter radial engine. Other than the peculiar Avia hallmark of having an upper wing with a shorter span than the lower, it was utterly conventional, even featuring a tail fin for the first time in a Pavel Beneš and Miroslav Hajn design (previous aircraft had a rudder but no fin).

Contents

Design and development

Initial tests of the first prototype were disappointing, displaying performance only marginally better than the BH-21, even when fitted with a more powerful version of the Jupiter. Two further prototypes followed, both designated BH-33-1, each with an increasingly powerful Jupiter variant – one a Jupiter VI, the other a Jupiter VII. The performance of the latter example was finally acceptable for the Czechoslovak defence ministry to order a small production run of only five aircraft.

Three examples were sold to Belgium, where there were plans to build the type under licence, but this did not occur. Licence production was undertaken, however, in Poland, where a single example was sold, along with a licence to build 50 aircraft. These were designated PWS-A and put into service with the Polish Air Force in 1930. [1]

Development continued with an almost total redesign of the fuselage, replacing the wooden, slab-sided structure with one of oval cross-section, built up from welded steel tubes. Designated BH-33E, this was a world-class fighter for its time. Nevertheless, the response from the Czechoslovak military was lukewarm (although two were bought for the national aerobatics team), and Avia again looked abroad for customers, this time selling 20 aircraft to the Kingdom of Yugoslavia, along with a licence to produce another 24. Two or three examples were also bought by Soviet Union for evaluation. [2]

Avia BH-33L Avia BH-33L.jpg
Avia BH-33L

In late 1929, a further development was flown as the BH-33L, featuring longer-span wings, and a Škoda L W-block engine. This version finally brought the company the domestic sales that it had been hoping for, with 80 aircraft ordered by the Czechoslovak Air Force. These became standard equipment with some air regiments up to the outbreak of World War II. [3]

A single, final variant with a BMW-built Pratt & Whitney Hornet engine was built as the BH-33H (later redesignation BH-133) in 1930, but this did not lead to production.

Operational history

Following the outbreak of the Spanish Civil War, a single BH-33 was covertly purchased in Belgium in August 1936 on behalf of the Spanish Republican Air Force. While it was delivered to Spain, the aircraft's machine guns had been removed when the aircraft and pilot was briefly detained in France before being released. [4] The planes were used by Spanish Republican Air Force during Spanish-Civil War. [5] Czechoslovak BH-33s never saw combat, and Poland's examples had long been replaced in service by the time of the German invasion. Two Yugoslavian machines did, however see combat against Luftwaffe Messerschmitt Bf 109s, but were both destroyed and their pilots killed.

Variants

BH-33
First prototype.
BH-33-1
Two prototypes powered by Jupiter VI (second) and Jupiter VII (third) engines plus five serial built aircraft with Jupiter VII engine.
BH-33E
Rebuilt fuselage
BH-33E-SHS
Yugoslav Version powered by IAM K9 engine, 22 built. [6]
BH-33L
Version with longer-span wings, powered by a Škoda L engine, 80 built.
BH-33H (BH-133)
Version powered by Pratt & Whitney Hornet engine, one built.
P.W.S.A
Polish license-built variant of the BH-33 with minor modifications, [1] 50 built between 1929 and 1932.

Operators

Flag of Belgium (civil).svg  Belgium
Flag of Independent State of Croatia.svg Independent State of Croatia
Flag of the Czech Republic.svg  Czechoslovakia
Flag of Greece.svg  Greece
Flag of Poland.svg  Poland
Flag of Slovakia.svg Slovakia
Flag of the Soviet Union.svg  Soviet Union
Flag of Spain 1931 1939.svg Spanish Republic
Flag of Yugoslavia (1918-1943).svg  Yugoslavia

Specifications (BH-33L)

Avia BH-33 Avia BH-33 drawing.jpg
Avia BH-33

Data from Jane's all the World's Aircraft 1928, [7] Combat aircraft of the world [8]

General characteristics

Performance

Armament

See also

Related development

Related lists

References

  1. 1 2 Belcarz 2005, p. 6.
  2. Taylor 1989, p. 86.
  3. Taylor and Alexander 1969, p. 58.
  4. Howson 1999, p. 88
  5. "Spanish Civil War Aircraft". www.zi.ku.dk. Archived from the original on 5 February 2015. Retrieved 1 August 2022.
  6. "Авиа BH-33". Archived from the original on 2014-04-07. Retrieved 2014-04-07.
  7. Grey, C.G., ed. (1928). Jane's all the World's Aircraft 1928. London: Sampson Low, Marston & company, ltd. p. 77c.
  8. Taylor, John W. R.; Alexander, Jean; et al. (1969). Combat aircraft of the world. London: Ebury P.; Michael Joseph. p. 58. ISBN   0-71810-564-8.
  9. "Avia BH-33".

Bibliography

Further reading