Arming and rearming torpedoes

[Lzs von swe]

Greetings
I have tried to find info on this, but no luck.
In real life, did the uboats go with the tubes loaded always or did they load them after an contact? As I understand it they could only arm (set gyro, depth, pistol etc.) the torpedoes in the torpedo room, prior to loading them into the tube.
If they did have the tubes loaded, what was the setting? How time consuming was the process of setting up the torpedo? If they did not have preset torpedoes in the tubes, how long did it take from when the settings in the TDC where set to an correctly armed torpedo in the tube, ready to be fired?:hmm:

[ronbrewer]

The following link has some torpedo information in chapter 3:

http://www.uboatarchive.net/U-841INT.htm

Looks like torpedos were stowed in the tubes during patrols. Though it doesn't provide information on if firing data could be applied while in the tube I'm thinking it could. What I'm not sure about is if the firing data could be updated after the tube doors were opened to flood the tubes.

Good questions, though.

Thanks,
Ron

[Lzs von swe]

Thanks, bookmarking that site

[Sailor Steve]

Torpedo gyro, and depth settings could be changed with the torpedo in the tube. The TDC would either tell the torpedomen the settings and they changed them with a tool, or the TDC sent the information directly to the torpedo via a spindle. Lining up the connections properly is one of the reasons it took so long to reload the torpedoes.

Here is a link to how the Americans did it, originally courtesy of Snowman999 in a thread on the SH4 boards:
http://www.maritime.org/fleetsub/tubes/index.htm

Scroll down to Chapter 7 for some good pictures.

As for the pistol, the best evidence I've seen is that arming the magnetic pistol had to be done outside the tube, without the switch that's in SH3; but I'm not 100% sure of that.

[TarJak]

There does not seem to be a lot of info on how pistol settings were made.

In here http://www.uboatarchive.net/BDUKTB30265.htm

Doenitz makes some interesting observations that give clues but no hard facts:

"Naval War Staff asked whether U-boats could now be operated off Narvik against enemy supplies. The answer was in the negative.

Reasons:

1) In that area it does not get dark any more, the boats would therefore have to operate in positions remote from the disembarking places and would only score chance successes.

It is certain that "MZ" does not function in that sea area, though there is still hope that better results may be obtained with this type of firing in the Atlantic. Experiences with "AZ" have been very bad.
3) The attack on English shipping routes has once more become of first importance.
4) Finally, this area was not cleared of U-boats without reason and these reasons have not changed.

U 26 sailed for Trondheim with supplies for the G.A.F.

U 37 reported in radio message 0045:

"1) Erik Frisell air driven torpedo spontaneous ignition 75 seconds. Sunk with gunfire.
2) Dunster Grange electric torpedo, "MZ" safe. No success. Electric torpedo "MZ" premature detonation 19 seconds. Air driven torpedo miss. Electric torpedo no success at 500 meters. Gun action broken off." In spite of the worst possible experiences during the Norway operation and in spite of the ever increasing danger of degaussing on the part of the enemy, I have not so far abandoned magnetic firing, for the following reasons:
1) Impact firing with switch setting "A" led to practically nothing but failures during October and April, partly because of bad depth-keeping, partly because of failure of the pistol itself.
2) "MZ" brought many successes in the southern and central North Sea and in the Atlantic (last February), despite a number of failures to fire and premature detonators.

Although information received made it appear more and more likely that the enemy was using degaussing, I still hoped to achieve something in open sea areas, until the "AZ" was satisfactorily improved.

A thorough examination of the pistol showed a number of faults in construction, and improvement and adaptation of various parts were begun.

Independently of this, I demanded that the English impact pistol captured in "Seal" be copied. We were to go over to "AZ" as soon as the pistol was in order for impact firing.

Today's report from U 37 alters the situation: of 5 torpedoes, 2 were premature detonators and 2 probably failed to fire. If one or two of the torpedoes were affected by degaussing cannot be decided on present information. In any case magnetic firing has become almost useless. Boats at sea have therefore been ordered to go over to "AZ" with switch setting "A".

It is quite clear to me that I must expect a further considerable number of failures due to the known defects of the "AZ", but

I have no other choice, unless I withdraw the boats altogether. But I cannot lay the boats up now, of all times, without damaging the whole arm to an unpredictable degree. As long as there is the chance of a small percentage of success, operations must be continued.

Work is already in progress on the adaptation of the impact firing unit. It is hoped that by inserting an electric contact a large proportion of the "AZ" failures will be avoided. The boats which are ready to sail will therefore be kept back until they have been fitted out with adapted pistols. The delay of 2-4 days can be accepted if it will mean better results."

[ronbrewer]

Boats at sea have therefore been ordered to go over to "AZ" with switch setting "A".

That's the interesting part for me. To go over to "AZ" sounds like a modification at the head of the torpedo and would seem to have to be done outside the tube like Sailor Steve alluded to.

[SmokinTep]

Interesting stuff. Thanks for the links.

[Jimbuna]

@Sailor Steve

Cool link

[HunterICX]

wow cool link steve,

reading the text and seeying the pictures its like

''How to Build your own Torpedo launcher''

[Lzs von swe]

Yea, you guys rock

Hm, think I´ll set two torps for impact and two for magnetic, and then decide the pistol setting on the reloads upon loading:hmm: Just to add a new dimension to the game