Special Aircraft Service

the SAS Hangar => The Lounge => Topic started by: Dreamk on May 27, 2015, 05:17:34 AM

Title: Torpedoes Historical Background - part 2 Soviet torpedoes
Post by: Dreamk on May 27, 2015, 05:17:34 AM

As previously stated, with the uploading of the new extended Torpedoes pack (https://www.sas1946.com/main/index.php/topic,46400.msg516525.html#msg516525), detailed performances data could be found in the pdf document attached to the pack, but the need was felt of details upon the historical back ground of these torpedoes.

So, after the Japanese Aerial torpedoes, let's have a look at the Soviet Aerial torpedoes
(A photo catalog of the various model appears in the main post of the Torpedoes pack https://www.sas1946.com/main/index.php/topic,46400.msg516528.html#msg516528 )

The Soviet torpedoes were based upon naval torpedo models in service with serving with the Soviet Fleet:

• The 45-12 series was based upon the naval torpedo model 1912 (45cm model 1912)
• The 45-15 series was based upon the naval torpedo light model 1910 modified 1915 (45cm 1910/15 L)
• The 45-36 series was based upon the 45H naval torpedo (45cm model 1936) – a license copy of an early model of the Italian Whitehead W200 torpedo series from 1933 (the W200 evolved, after many improvements, into the F200 that entered in service with the Italian AeroSiluranti and the beginning of WW2).
• The 53-27 series was a tentative made in the early thirties to use the 53cm naval torpedo model 1927, with a heavier explosive head, as a basis for a heavy aviation torpedo.

Torpedoes were classified, according to their height of drop, in low altitude (TAN, later AN) and high altitude (TAV, later AVO then AV-A). At the end of ww2 appeared new models AM and CN, developments of captured German F5W torpedoes, these last torpedoes being based themselves originally upon the Italian Whitehead F170 torpedoes.

• High altitude torpedoes:
  The TAV torpedoes were dropped using a heavy, cumbersome, 3-staged, multi parachutes system. The weight of all the parachute system alone was about a ton. After entering in water these torpedoes were set to run either in circles or in spiral.
  
  • The TAV-12 (45-12AVO), TAV-15 (45-15 AVO) and TAV-27 (53-27AVO) were tested. Only the TAV-12 and TAV-15 entered in service. Then, in 1932, the TAV-15 was selected to become the standard high-altitude aviation torpedo.
  • In 1938 was introduced the 45-36AV-A (A for the name of its designer, Alferov). It used a single parachute, stored, together with its launching rope, in a profiled box attached to the aircraft
• Low altitude torpedoes:
  The low altitude AN torpedoes had to be dropped below the height of 15m and at low speeds. After entering in water they ran in straight course.
  
  • The standard low altitude torpedoes of the thirties were the TAN-12 (45-12AN), the TAN-15 (45-15AN).
  • The 45-12AN broke frequently at the entry in water. The 45-15AN had a stronger head.
  • In 1939 was introduced the 45-36AN. It was to remain the mainstay of the Soviet torpedo squadrons for all the duration of WW2.
  • In 1944 was introduced the improved performances 45-36ANU, with a heavier explosive head.
  • At the end of WW2 was introduced the 45-36AM, using a stock of German F5W captured in a factory in Pomerania. The torpedo had a reinforced tail and figured a wooden shock absorber over the head, similar to the one seen on American late war Mk13 models.

The optimal angles of entry in the water were assessed as being within 12-18 °. At smaller angles of entry into water (about 5-10 °) the torpedo would often ricochet, leading to their deformation. At angles of more than 18 °, the torpedo would get stuck into the sea bottom if the depth of the waters was less than 50m.

To insure an optimal angle of entry in water and prevent damage to the torpedo, stabilizers were developed under the direction of Commissar Kravtsev. They had a very limited influence on the drop conditions, both in terms of height and speed.

• The T-18 system used in conjunction with 45-15AN torpedoes was a beam rack insuring, by a system of ropes and pulleys, a controlled release of the torpedo from the aircraft, so as to keep a steady optimal angle. Cumbersome and not very efficient it was soon superseded by tail stabilizers.
• The 45-36AN-42 was equipped with a cylindrical steel stabilizer. Introduced in 1942, it allowed torpedoes to be dropped at heights of 15 to 55 m, and at maximum speed of 300 km/h.
• The 45-36AN-S was equipped with a simple wooden stabilizer reinforced with metal bars, designed by Major Sagayduk. Kravtsev claimed later to be the original designer of this successful stabilizer. Sagayduk understood the urgent needs the torpedo squadrons crews and acted upon the well know principle that “Best in the worst enemy of good”. He decided upon his own authority to complete the development of this stabilizer and deliver it to the operational units, instead of waiting for optimal completion of its development, that could and would take years – there was a war going on…. This stabilizer appears upside down on photographs of IL-4T planes, by comparison with its official drawings – this may reflect this dispute between its designers.
  The Sagayduk stabilizer, introduced in 1942, allowed the torpedo to be dropped within 10-45 m height in waters more than 12 m deep. It would see service till 1951.
• The 45-36CN-45, was introduced in 1945 and would be the best Soviet torpedo stabilizer. A simple design of lightweight metallic “cross and ring”, adapted to the higher speeds of the new torpedo bombers, it would continue being used after the war.
  

Radio-controlled torpedoes:
The TAN-12RUT and TAV-12RUT were a tentative to develop radio controlled, both of low and high altitude, based upon the 45-12AN. It did not lead to series production. The torpedo had colored lights installed on their upper surface, in order to help the operator, aboard the torpedo bomber, to guide them in the water

Torpedo Designation Soviet 45-12AN (TAN-12) 45-12AV-A (TAV-12A) 45-15AN 45-15AV-A (TAV-15) 53-27AN 53-27AV-A (TAV-27) 45-36AN 39 (45-36AN) 45-36AN T-18 45-36AN-S (Sagayduk) 45-36AN-SIL4 45-36AN 42 45-36AV-A (39) 45-36ANU (44) 45-36AV-A (42) 45-36CN 45 (ANU 45) 45-36AM

Max drop speed (km/h)   150 200 160 200 160 160 250 250 250 250 300 250 360 400 400 400

Min Drop Height (m)   10 10 10 600 10 600 10 25 10 10 15 10 20 300 20 20

Max Drop Height (m)   15 2000 20 4000 20 4000 35 35 45 45 56 300 40 3000 100 100

Weight (kg)   665 930 /665 720 1180 /720 1675 1675 950 935 935 935 978 955 940 935 943 943

Explosive (kg)   100 100 132 132 200 200 200 200 200 200 200 200 200 200 200 200

Speed (km/h)   34 53 53 58 79 79 76 76 72 72 72 76 72 72 72 72

Range (m)   2000 3000 3000 3000 1500 1500 3000 3000 4000 4000 4000 3000 4000 4000 4000 4000