Search
Close this search box.

Avia BH-33

The Avia BH-33, constructed in Czechoslovakia in 1927, was a biplane fighter aircraft that took inspiration from the BH-21J model.

This new aircraft combined the original BH-21 airframe with a Bristol Jupiter radial engine, resulting in promising performance.

Noteworthy for its unique design, the Avia BH-33 featured an upper wing with a shorter span than the lower wing, a characteristic that set it apart.

Additionally, this aircraft was the first design by Pavel Beneš and Miroslav Hajn to include a tail fin, a departure from previous models that only had a rudder.

The first prototype’s initial tests yielded unsatisfactory results, showing performance that was only slightly superior to the BH-21, even with a more robust version of the Jupiter engine.

Subsequent prototypes, both labelled BH-33-1, were developed with more powerful Jupiter variants – one featuring a Jupiter VI, and the other a Jupiter VII.

The performance of the latter prototype met the standards set by the Czechoslovakian defence ministry, leading to an order for a limited production run of just five aircraft.

Belgium purchased three examples of the aircraft, with intentions of manufacturing it under licence.

However, this plan did not come to fruition.

On the other hand, Poland took up the task of licence production and acquired one aircraft, along with the rights to construct 50 more.

These aircraft, known as PWS-A, were successfully integrated into the Polish Air Force in 1930.

Subsequently, the development of the aircraft progressed, resulting in a significant overhaul of the fuselage.

The previous wooden, slab-sided structure was replaced with an oval cross-section made from welded steel tubes.

This upgraded version, designated as BH-33E, gained recognition as a top-tier fighter during its era.

However, despite the lack of interest from the Czechoslovakian military (except for two aircraft purchased for the national aerobatics team), Avia decided to explore international markets once again.

This time, they successfully sold 20 aircraft to the Kingdom of Yugoslavia and even obtained a licence to manufacture an additional 24 planes.

Additionally, a few examples were acquired by the Soviet Union for evaluation purposes.

In the later part of 1929, Avia introduced a new version called the BH-33L.

This variant featured longer-span wings and was equipped with a Škoda L W-block engine.

The BH-33L proved to be a significant milestone for the company, as it finally attracted domestic sales.

The Czechoslovak Air Force placed an order for 80 aircraft, fulfilling Avia’s long-awaited hopes.

These aircraft became standard equipment within certain air regiments and remained in service until the outbreak of World War II.

Despite the company’s efforts, only one final variant, the BH-33H (later redesignated as BH-133), equipped with a BMW built Pratt & Whitney Hornet engine, was built in 1930.

Unfortunately, this variant did not progress to mass production.

Variants

BH-33

First prototype.

BH-33-1

Two prototypes powered by Jupiter VI (second)

&

Jupiter VII (third) engines plus five serially built aircraft with Jupiter VII engines.

BH-33E

Rebuilt fuselage

BH-33E-SHS

Yugoslav Version powered by IAM K9 engine, 22 built.

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, 

50 built between 1929 and 1932.

Specifications

BH-33L

Crew

One

Length

7.22 m (23 ft 8 in)

Wingspan

8.90 m (29 ft 2 in)

Height

3.13 m (10 ft 3 in)

Wing area

25.5 m2 (274 sq ft)

Empty weight

1,117 kg (2,463 lb)

Gross weight

1,560 kg (3,439 lb)

Powerplant

1 × Škoda L , 430 kW (580 hp)

Performance

Maximum speed

298 km/h (186 mph, 162 kn)

Cruise speed

280 km/h (174 mph, 151 kn)

Range

450 km (280 mi, 240 nmi)

Service ceiling

8,000 m (26,247 ft)

Rate of climb

9.9 m/s (1,940 ft/min)

Armament

2 × fixed forward firing 7.7 mm (.303 in) Vickers machine guns

Or

2 × fixed forward firing 7.92mm vz.28 machine guns

Sources
Czechoslovakian Air Force, 1918-1970, Aircam Aviation Special 05-Richard Ward, Zdenek Titz & Gordon C. Davies.
Ceskoslovenské Letectvo, 1918-1924-Jiří Rajlich & Jiří Sehnal.

Avia BH-33-Jiri Vrany.

Polish Aircraft 1893-1939-Jerzy B. Cynk.

 

Share on facebook