At the start of the second world war, the polish air force mostly used old WWI era P.u.W bombs, left behind by the Germans after the Wielkopolska uprising of 1918–1919, and while production on domestic bombs had started to replace the aging P.u.W bombs, the larger variants were still used. In 1932 the stockpile of P.u.W 12.5 started to get low, and the remaining 4800 bombs were converted into training bombs.
German bombs
P.u.W
These first world war era bombs were developed by the Prufanstalt und Werft der Fliergertruppe, the Test establishment and Workshop of the Aviation Troops as an improvement over earlier bombs. They were constructed with high grade steel instead of cast iron to improve penetration, and the fins were slightly angled. They were produced in different weights, 12.5 kg, 50 kg, 100 kg, 300 kg and 1000 kg. After the war stocks of the 4 lighter variants were captured at Poznan-Lawica airfield and the Polish used them till the second world war. During the second world war, the 300kg variant was barely used because it was very difficult to load it onto the PzL.37 bombers due to bad infrastructure.
construction
The bombs were usually painted light blue, with a brass colored fuse at the nose. Reportedly some bombs were also painted light to medium grey, with a black fuse. The wings are angled, giving the bomb a spin during flight. This improved the stability of the bomb and activates the fuse. This design didn’t really change between the different size bombs, just the scale.
| Designation | length | diameter | explosive mass | |
| P.u.W 12.5 kg | 75 cm | 9 cm | 1.2 kg |  |
| P.u.W 50 kg | 170 cm | 16.2 cm | 17 kg |  |
| P.u.W 75 kg | 170 cm | 16 cm | 20 kg |  |
| P.u.W 100 kg | 191 cm | 24,2 cm | 40 kg |  |
| P.u.W 300 kg | 275 cm | 36,5 cm | 185 kg | |
| P.u.W 5 kg incendiary | 75,8 cm | 9 cm | 1 kg |  |
| P.u.W 10 kg incendiary | 84 cm | 13,5 cm | 2,5 kg |
From left to right: P.u.w 12.5 kg, 50 kg, 100 kg and 300 kg 
From left to right: P.u.w 100 kg, 300 kg and 1000 kg
other german bombs
Together with the P.u.W bombs, the Polish also captured German stockpiles of different types of bombs.
B-1e “electron”
The B-1e electron brandbombe was a small anti-personnel incendiary bomb, used to burn down industrial facilities. The bomb was build with a electron casing and a termite filling.
The bomb didn’t explode, but rather ignited by a small the incendiary materials with a small concussion charge in the nose.
| Designation | length | diameter | mass |
| B-1e | 35,2 cm | 5 cm | 0,968 kg |
Polish bombs
WZ. Series
In the 1920’s the polish air force needed new bombs to replace the aging P.u.W bombs. In the late 1920 the wz.29 was developed based on the P.u.W 12.5kg.
Fragmentation and air bombs
| designation | weight | length | diameter | notes | |
|---|---|---|---|---|---|
| wz. 27 | 12 kg | 69.2 cm | 9 cm | Modeled after the German P.u.W 12.5 kg bomb, the bomb could be suspended both vertically and horizontally. The PG-27 fuse in the nose was also modeled after the German counterpart and armed by centrifugal force. |  |
| wz. 29 | 50 kg | 115.8 cm | 19.5 cm | Initially pressed from solid steel, it was later constructed from thick walled steel tubes. After dropping the bomb, the detonator was primed by the unscrewing of the fan |
 |
| Ż wz. 31 | 100 kg | 140 cm | 27.5 | This two part bomb had a nose made from thick sheet metal and a rear of thinner sheet metal. An eye was welded to the top to suspend the bomb to the bomber. Painted with gray oil paint. Over the course of 1939 planes of the polish air force likely dropped about 119 tons of these bombs with PzL.37 and PzL.23 aircraft. |
 |
| T wz. 32 | 50 kg | 115.8 cm | 19.5 cm | Improved version of the wz. 29, designed by Mikolaj Tarnowski. Supposedly a less labor intensive production method was used. | |
| wz. 33 | 12 kg | 69.2 cm | 9 cm | In the early 1930’s the wz. 27’s construction was upgraded and dubbed the wz. 33. Like the wz. 27, this bomb was still similar to the P.u.W 12.5. | |
| T wz. 34 | 0.8 kg | 36 cm | 3.4 cm | The wz. 34 “myszka lotnicza” (flying mouse) was an anti personnel fragmentation bomb designed by Captain Mikolaj Tarnowski as a successor to the German no. 2 flying mouse bombs. It was designed so that it could be created in small factories if necessary. Therefore the main body was a gas pipe. |  |
| wz. 35 | 12 kg | 64.5 cm | 9 cm | In1935, this improved version of the wz. 27 stared production. While the shape was still similar to it’s predecessors, it had four fins instead of three and had a push detonator instead of the centrifugal detonator. |  |
| wz. 36 | 12 kg | 64.5 cm | 9 cm | Export version of the wz. 35 intended for Bulgaria, with a longer fins and an additional hook for vertical ejection. | |
| wz. 39 | 200 kg | 159.3 cm | 34 cm | constructed in 1938. Designated BS-530 during development phase. First Polish developed cylindrical bomb. |  |
| designation | weight | length | diameter | notes | |
|---|---|---|---|---|---|
| wz. 27 | 12 kg | 69.2 cm | 9 cm | Modeled after the German P.u.W 12.5 kg bomb, the bomb could be suspended both vertically and horizontally. The PG-27 fuse in the nose was also modeled after the German counterpart and armed by centrifugal force. | |
| wz. 29 | 50 kg | 115.8 cm | 19.5 cm | Initially pressed from solid steel, it was later constructed from thick walled steel tubes. After dropping the bomb, the detonator was primed by the unscrewing of the fan |
|
| Ż wz. 31 | 100 kg | 140 cm | 27.5 | This two part bomb had a nose made from thick sheet metal and a rear of thinner sheet metal. An eye was welded to the top to suspend the bomb to the bomber. Painted with gray oil paint. Over the course of 1939 planes of the polish air force likely dropped about 119 tons of these bombs with PzL.37 and PzL.23 aircraft. |
|
| T wz. 32 | 50 kg | 115.8 cm | 19.5 cm | Improved version of the wz. 29, designed by Mikolaj Tarnowski. Supposedly a less labor intensive production method was used. | |
| wz. 33 | 12 kg | 69.2 cm | 9 cm | In the early 1930’s the wz. 27’s construction was upgraded and dubbed the wz. 33. Like the wz. 27, this bomb was still similar to the P.u.W 12.5. | |
| T wz. 34 | 0.8 kg | 36 cm | 3.4 cm | The wz. 34 “myszka lotnicza” (flying mouse) was an anti personnel fragmentation bomb designed by Captain Mikolaj Tarnowski as a successor to the German no. 2 flying mouse bombs. It was designed so that it could be created in small factories if necessary. Therefore the main body was a gas pipe. |  |
| wz. 35 | 12 kg | 64.5 cm | 9 cm | In1935, this improved version of the wz. 27 stared production. While the shape was still similar to it’s predecessors, it had four fins instead of three and had a push detonator instead of the centrifugal detonator. | |
| wz. 36 | 12 kg | 64.5 cm | 9 cm | Export version of the wz. 35 intended for Bulgaria, with a longer fins and an additional hook for vertical ejection. | |
| wz. 39 | 200 kg | 159.3 cm | 34 cm | constructed in 1938. Designated BS-530 during development phase. First Polish developed cylindrical bomb. | |
Incendiary bombs
| designation | weight | length | diameter | notes | |
|---|---|---|---|---|---|
| wz. 32 | 0.22 kg | 18 cm | 3.4 cm | These bombs were hung under ejectors in cardridges each containing 20 bombs. The minimum drop height was 100 m. | |
| wz. 38 | 12 kg | 72.5 cm | 10 cm | Incendiary bomb. Presumably it was filled with rods made of a compressed mixture of tar, sulfur and an oxidant or compressed termite. |  |
Smoke bombs
| designation | weight | length | diameter | notes | |
|---|---|---|---|---|---|
| G. wz.34 | 10 kg | Produced form 1934 to 1936, this bomb was not mass produced in favour of the 50 kg variant | |||
| G. wz.34 | 50 kg | Produced from 1934 to 1936. |
training bombs
| designation | weight | length | diameter | notes | |
|---|---|---|---|---|---|
| Bomba ślepa 15 kg wz. 39 | 15 kg | 62.5 cm | 9 cm | The dimensions of this bomb were identical to the wz. 33 fragmentation bomb. Introduced in 1939, manufacturer Huta Ludwików received an order for 10000 bombs. 3000 bombs were delivered in June, with the remainder were delivered in December of the same Year. The bomb had a tear shaped body made out of pig iron with four fins. On impact the bomb caused a smoke cloud to see the location up to 4000 meter high. |
|
| Bomba ślepa 6 kg | 6 kg | 60 cm | 10.5 cm | On impact the bomb caused a smoke cloud to see the location of impact up to 4000 meter high. Made out of concrete. |
|
| Bomba ślepa 7 kg wz. 31 | 7 kg | Improved version of the 6 kg training bomb. On impact the bomb caused a smoke cloud to see the location of impact up to 4000 meter high. The front end was made out of 1 part concrete and two parts iron. The back was made of two parts river sand. |
BS Series
The earlier wz. bombs were all teardrop shaped, which gave difficulty fitting these bombs into newer, faster bombers. Mid 1938 a joint venture of Wielkie Pieców and Zakłady Ostrowieckich developed a series of cylindrical bombs. On basis of positive test results, the 200 kg heavy BS 530 was selected for a production run of 100 bombs and given the designation wz.39.
| designation | diameter | length | total weight | explosive mass |
|---|---|---|---|---|
| BS-310 | 19.7 cm | 115 cm | 51.6 kg | 28.3 kg |
| BS-320 | 21 cm | 99 cm | 50.5kig | 27.8 kg |
| BS-330 | 20.5 cm | 103 cm | 50.1 kg | 27.1 kg |
| BS-410 | 27.5 cm | 119.7 cm | 100.1 kg | 54.3 kg |
| BS-420 | 24 cm | 139.2 cm | 99.7 kg | 54.7 kg |
| BS-425 | 26 cm | 134.3 cm | 100 kg | 56.5 kg |
| BS-430 | 26.4 cm | 129.2 cm | 100 kg | 56.6 kg |
| BS-530 | 34 cm | 159.3 cm | 198.7 kg | 114.3 kg |
Sources
Adam Popiel: Armament of Polish aviation 1918-1939