Default setting for Torpedo pistol selector?

sharkbit · 03-31-12, 05:38 PM

Quote:

Originally Posted by Sailor Steve

We're much luckier than the real kaleuns were. They didn't have a switch that could give you one or the other. To change the torpedo warhead had to be physically removed and the pistos switch out. The operation took about an hour.

Sorry to necro this, but...
I've always been curious about this aspect. I've always been under the impression this is true with US torpedoes but I've never read anything about German torpedoes.

So one of my "personal realism settings" has always been to select one or the other prior to action and not switch it in the middle of the action, both in SH3 and SH4.

While surfing last night, I came across this on the U-boat Archive website about torpedo pistols:

"Pi 2 (Pi 39H) December 1942 Selectable impact and magnetic or impact alone (new German designed magnetic detonator - impact mechanism same as Pi1) G7e TIII "

Here's the link showing the whole article and all of the different pistols and dates used(it is less than a third of the way down on the page):

http://www.uboatarchive.net/KTBNotesArmament.htm

I interperate that as it was selectable at time of firing from 12/42 on on the T3 eels. Earlier pistols didn't seem to be selectable. I'm going to try to some more digging and see if I can find anything more definite.

Gargamel · 03-31-12, 09:37 PM

7.5 points! Good post!

Sorry, I have nothing intelligent to add.

Sailor Steve · 04-01-12, 12:26 AM

Quote:

Originally Posted by sharkbit

Sorry to necro this, but...
I've always been curious about this aspect. I've always been under the impression this is true with US torpedoes but I've never read anything about German torpedoes.

And there's new information. This is the source.
http://eaglescholar.georgiasouthern...._201005_MA.pdf

I got some grief awhile back when I pointed out that there was a switch, but it wasn't available until late 1943, when the magnetic problem was solved. On page 30 the author says that the switch was there from the beginning. Later, on page 48 he says "At the time U-boats carried torpedoes equipped with either the MZ or AZ pistol. The option that would later allow the commander to interchange these settings while on patrol had not yet come into being, so whatever setting the pistol was set to when delivered to the boat was what it was stuck with for the duration of the patrol. It was impossible, in other words, for a commander to change his torpedo’s pistols from MZ to AZ setting and vice-versa.

Either way, the documents should keep you entertained for quite some time.

bigboywooly · 04-01-12, 01:24 AM

Interesting
If you read the KTBs etc of the Norway assault the magnetic failures are well documented.
Boats at sea were advised to change all fuses for impact as magnetic couldnt be trusted.( Later to be found out that impact didnt work correctly either )
So by that reasoning it was possible for them to change fuse types after delivery

Sailor Steve · 04-01-12, 01:52 PM

Quote:

Originally Posted by bigboywooly

So by that reasoning it was possible for them to change fuse types after delivery

It was my understanding before that they could be changed, but they had to be physically replaced. Maybe that was the case at the beginning. Or maybe they were like the US torpedoes, with both types installed, and the magnetic ones had to be removed.

It's hard to tell.

bigboywooly · 04-01-12, 01:58 PM

Yeah not simple
I was under the impression was a setting changed under an inspection panel which is why torps had to be removed from tubes in order to carry out the switch.

You would think with the amount of the things fired there would be plenty of info about on them

Mittelwaechter · 04-01-12, 02:34 PM

The pistol was a combination of an 'allways on' impact mechanism plus a magnetically triggered electric mechanism - switchable to be on/off.
Why should there have been a problem to switch this electric function on/off at torpedos in the tubes, while they could be simply manipulated for running depth, speed and gyroangle?
To switch the mag fuse off you would have had to disconnect/switch an electric circuit and the system would have been disabled.

They had to care for the sensitivity of the magnetic mechanism due to different intensities of the earth magnetic field in different regions.
Therefore they had to remove the torpedos from the tubes to update the mag fuse settings for the current region - as for several other maintenance.
It was a huge problem in the North Sea, because there are pretty much iron ore fields in rather shallow water conditions to irritate the mag fuse.
It was one of the reasons for premature detonations or duds under the keel - they simply didn't match the required sensitivity conditions.

The other major problem with the German torpeos was a little calibrated pressure chamber inside the torpedos - relevant for keeping the set running depth.
This chamber was leaky and influenced by the high pressure conditions during deep diving periods of the U-Boot.

zygoma · 04-01-12, 02:59 PM

Somewhere in this thread someone posed the question of whether or not the magnetic declination in the northern latitudes of the North Atlantic might interfere with the magnetic pistols. I believe it should not.
Declination, while it does vary with time, is a very slow process, and would only interfere with navigation by magnetic compasses were it not factored in to one's calculations. While there are local anomalies in several places on the face of the earth, declination changes very slowly. Herr Kapitan Mittelwaechter's point about adjusting for the anomalies is well taken.
I lived for many years in New Jersey, then for even longer in Fairbanks, Alaska. In New Jersey, the declination (difference between magnetic and true north) was only 11° 37' W, changing by 0° 2' W/year. That same year (1972), declination was 28° 53' E changing, by 0° 1' W/year. It's changed over the past 40 years to 20° 7' E changing, by 0° 22' W/year.
So, while it *does* vary with location and time, it's always (well, nearly always) printed on navigation charts, USGS topo maps, and the like.
Since the torpedo was only using a magnetic field disturbance detector to fire its detonator, and not for finding its way, it would never know about the drift of the magnetic north pole.
<sigh> Every once in awhile my old Boy Scout stuff comes struggling out of my brain and rears its ugly head.....
Zygoma
________________________________________________
May all your submarine's surface operations exceed your number of dives by exactly one at the end of your career.

03-31-12, 09:37 PM	#2
Gargamel Lucky Sailor Join Date: Oct 2010 Location: Rome Posts: 4,273 Downloads: 81 Uploads: 0	7.5 points! Good post! Sorry, I have nothing intelligent to add. __________________ Luck is a residue of Design.

04-01-12, 01:24 AM	#4
bigboywooly Rear Admiral Join Date: Apr 2006 Location: Swindon, England Posts: 10,151 Downloads: 35 Uploads: 0	Interesting If you read the KTBs etc of the Norway assault the magnetic failures are well documented. Boats at sea were advised to change all fuses for impact as magnetic couldnt be trusted.( Later to be found out that impact didnt work correctly either ) So by that reasoning it was possible for them to change fuse types after delivery __________________ My mediafire page http://www.mediafire.com/?11eoq19bq9r41

04-01-12, 01:58 PM	#6
bigboywooly Rear Admiral Join Date: Apr 2006 Location: Swindon, England Posts: 10,151 Downloads: 35 Uploads: 0	Yeah not simple I was under the impression was a setting changed under an inspection panel which is why torps had to be removed from tubes in order to carry out the switch. You would think with the amount of the things fired there would be plenty of info about on them __________________ My mediafire page http://www.mediafire.com/?11eoq19bq9r41

04-01-12, 02:34 PM	#7
Mittelwaechter The Old Man Join Date: Apr 2007 Posts: 1,304 Downloads: 35 Uploads: 0	The pistol was a combination of an 'allways on' impact mechanism plus a magnetically triggered electric mechanism - switchable to be on/off. Why should there have been a problem to switch this electric function on/off at torpedos in the tubes, while they could be simply manipulated for running depth, speed and gyroangle? To switch the mag fuse off you would have had to disconnect/switch an electric circuit and the system would have been disabled. They had to care for the sensitivity of the magnetic mechanism due to different intensities of the earth magnetic field in different regions. Therefore they had to remove the torpedos from the tubes to update the mag fuse settings for the current region - as for several other maintenance. It was a huge problem in the North Sea, because there are pretty much iron ore fields in rather shallow water conditions to irritate the mag fuse. It was one of the reasons for premature detonations or duds under the keel - they simply didn't match the required sensitivity conditions. The other major problem with the German torpeos was a little calibrated pressure chamber inside the torpedos - relevant for keeping the set running depth. This chamber was leaky and influenced by the high pressure conditions during deep diving periods of the U-Boot. __________________ 10 happy wolves rear 90 blinded, ensnared sheep. 90 happy sheep banish the wolves. Arrest the 1% - https://www.youtube.com/watch?v=dQ6hg1oNeGE

04-01-12, 02:59 PM	#8
zygoma Loader Join Date: Sep 2006 Posts: 84 Downloads: 66 Uploads: 0	Somewhere in this thread someone posed the question of whether or not the magnetic declination in the northern latitudes of the North Atlantic might interfere with the magnetic pistols. I believe it should not. Declination, while it does vary with time, is a very slow process, and would only interfere with navigation by magnetic compasses were it not factored in to one's calculations. While there are local anomalies in several places on the face of the earth, declination changes very slowly. Herr Kapitan Mittelwaechter's point about adjusting for the anomalies is well taken. I lived for many years in New Jersey, then for even longer in Fairbanks, Alaska. In New Jersey, the declination (difference between magnetic and true north) was only 11° 37' W, changing by 0° 2' W/year. That same year (1972), declination was 28° 53' E changing, by 0° 1' W/year. It's changed over the past 40 years to 20° 7' E changing, by 0° 22' W/year. So, while it does vary with location and time, it's always (well, nearly always) printed on navigation charts, USGS topo maps, and the like. Since the torpedo was only using a magnetic field disturbance detector to fire its detonator, and not for finding its way, it would never know about the drift of the magnetic north pole. <sigh> Every once in awhile my old Boy Scout stuff comes struggling out of my brain and rears its ugly head..... Zygoma ________________________________________________ May all your submarine's surface operations exceed your number of dives by exactly one at the end of your career.