Avia BH-21
| Avia BH-21 | |
|---|---|
|
|
| Type: | Fighter plane |
| Design country: | |
| Manufacturer: | |
| First flight: |
January 1925 |
| Production time: |
1925–? |
| Number of pieces: |
184 |
The Avia BH-21 was a Czechoslovakian biplane - fighter from the second half of the 1920s. It was designed by Pavel Beneš and Miroslav Hajn.
history
It was created as the successor to the BH-17 , which was only built in small numbers because it was difficult to fly. The BH-21 was designed to solve this problem. Some changes have been made; so the I-stems between the upper and lower wings were replaced by N-stems, the view to the front was improved and a different cooler was installed. As with all Avia fighters of that time , the BH-21 was given a slightly larger lower wing than an upper wing.
The first flight took place in January 1925. The tests showed better performance compared to the BH-17. The Czechoslovak Air Force then ordered a series of 137 aircraft, which they used under the military designation B-21 until the early 1930s.
The BH-21 successfully took part in an international competition in Belgium in 1925, whereupon license agreements were concluded with Belgian companies. 39 B-21s were made by SABCA and five more by SEGA.
A special version for racing competitions was created in the spring of 1925 under the name BH-21R . In contrast to the conventional BH-21, this version had a more powerful Hispano-Suiza 8 Fb with 400 HP and a special Reed-Levasseur propeller. In September of the same year, this type won the national speed race over 200 km with an average speed of 300.59 km / h. An unarmed training version was given the designation BH-22 .
One as BH-21J Marked execution was a Bristol-Jupiter - radial engine tested. This model was later used to create the BH-33 , which replaced the BH-21 in the air force in the early 1930s.
Military use
Technical specifications
| Parameter | Data |
|---|---|
| Constructor (s) | Pavel Beneš / Miroslav Hajn |
| span | 8.90 m |
| length | 6.87 m |
| height | 2.74 m |
| Wing area | 21.96 m² |
| Wing loading | 49.5 kg / m² |
| Empty mass | 720 kg |
| Takeoff mass | maximum 1084 kg |
| Engine (s) | a liquid-cooled V8 Hispano-Suiza 8Fb (license Škoda) |
| power | 228 kW (310 hp) |
| Top speed | 245 km / h at an altitude of 3000 m |
| Rise time | 13 min at 5000 m |
| Summit height | 5500 m |
| Range | 550 km |
| crew | 1 pilot |
| Armament | two 7.7 mm rigid Vickers machine guns above the engine |
literature
- Jan Krumbach, Jiří Vraný, Zdeněk Hurt: Avia BH-21, Jak-15, -17 a -23, Supermarine Spitfire Mk.IX a Mk.XVI. Naše vojsko, Prague 1986.
- Avia B-21. In: L + K. 1, r. L.
- Václav Němeček: Československá letadla. Part 1, Naše vojsko, Prague 1958.
- Zdeněk Pilát: Naše letecké motory. In: L + K. 5-10, r. LX.
