Questions regarding historical/realistic torpedo settings

Originally Posted by Albrecht Von Hesse

With regards to impact and magnetic pistols, what was involved in changing from one to the other? How long did that take, and could that be performed once the torpedo was in it's tube (outer door closed and outer door open)?

With regards to setting running depth, what was involved to do that? Again, how long did that take to do, and could that be performed once the torpedo was in it's tube (outer door closed and outer door open)?

At the moment doing either is the work of a moment to click impact versus magnetic settings, and the same goes to changing running depth. For one, I'm honestly interested in learning how their torpedoes were fuzed and set, and for another I want to operate/play setting torpedoes realistically.

I've read numerous books on u-boat history and I don't recall any reference to the procedure or method for changing magnetic to contact pistol. I do recall that the magnetic pistol would fire on either the magnet change or on direct contact. I assume if one wished to use a contact only pistol, that would require the torpedo to be pulled out of the tube and a contact only pistol put in place of the magnetic/contact pistol. In the early stage of the war (prior to and immediately after the Norway invasion) commanders were ordered to use contact only pistols.

As to running depth, I'd assume they had some type of mechanism or tool to set the running depth of the torpedo while it was in the tube.

Memoirs by Karl Doentiz gives a pretty good explanation of the torpedo and pistol problems during the war. Besides the defective magnet pistol there were other torpedo malfunctions which made diagnosis of the torpedo problem very difficult to solve: (1) The contact pistol would not always fire on a direct hit because the design of the contact pistol was extremely complex and just poorly designed. I believe this was overcome by recovering a British torpedo and using their rather simple design. (2) Initially the fins on the contact pistol were made in too small a diameter and/or too few fins which resulted in the torpedo bouncing off the side of a ship if the torpedo hit with less than 90-degree angle. (3) There was a major problem with running depth for quite a long period of time. Orders were sent out to set running depth 2 to 3 meters shallower than desired to try to over come this problem, but running depth remained very irratic. The problem was corrected only when the pressure sensing device used to control running depth was found not to be air tight. Air pressure built up in the u-boat as it submerged for longer periods of time, the pressure changed in the sensing device due to air leakage and this caused the torpedo to run deeper that set.

Therefore, in my humble opinion, to be realistic as much as the game will allow, I set the pistol on contact only and use a shallow running depth (1 to 3 meters). I hope this is helpful. And, read as many u-boat books as you can find, they'll give you a great deal of insight.