Torpedo Stowage

[Mittelwaechter]

They stored G7e aft internal!

KTB Schepke - U-100 - Type VIIb - 2nd War Patrol - Sept. 40
http://www.uboatarchive.net/KTB100-2.htm

Page 11 - 23.15 "Firing tube V G7e relative bearing to target 080°, target speed 8 knots, depth 3 meters, distance 54 seconds."
Page 13 - 0050 "Torpedo fired from tube V, G7e. Relative bearing to target 80°, target speed 8 knots, depth 2 meters, distance 53 seconds."


KTB Metzler - U-69 - 1st Type VIIc - 3rd War Patrol - May to July 41
http://www.uboatarchive.net/KTB69-3.htm

Page 7 - 09.49 "To avoid surprises, gave the steamer a stern shot: Bow left, target angle 90°, depth 2 meters, Eto tube runner ejected with mine gear - Crash dive. Running time 127 seconds - 1900 meters. Hit center." (Eto = Electric torpedo)
Page 8 - 00.36 "Coup de grâce: Stern shot Eto depth 3 meters. Again a tube runner - ejected with the mine gear - running time 30 seconds = 625 meters. Hit center: Steamer sinks immediately."

TypeVIIb and Type VIIc - 1940/1941 - both have performed two stern shots with G7e/Eto

[Aquelarrefox]

hey in external store they could carry fat or lut gas torpedos, or sonly g7aI

[Mittelwaechter]

The FAT and LUT systems were mechanic devices (interconnected rotable disks) to be set from outside the tubes via a special retractable gear (a spindle through the tube wall into the torpedo). There was no maintenance necessary. The external reserves were stored dry, so it shouldn't have been a problem to store a G7a FAT or LUT in the deck containers.

I don't know if they did it.

[LGN1]

Originally Posted by Mittelwaechter

They stored G7e aft internal!

KTB Schepke - U-100 - Type VIIb - 2nd War Patrol - Sept. 40
http://www.uboatarchive.net/KTB100-2.htm

Page 11 - 23.15 "Firing tube V G7e relative bearing to target 080°, target speed 8 knots, depth 3 meters, distance 54 seconds."
Page 13 - 0050 "Torpedo fired from tube V, G7e. Relative bearing to target 80°, target speed 8 knots, depth 2 meters, distance 53 seconds."


KTB Metzler - U-69 - 1st Type VIIc - 3rd War Patrol - May to July 41
http://www.uboatarchive.net/KTB69-3.htm

Page 7 - 09.49 "To avoid surprises, gave the steamer a stern shot: Bow left, target angle 90°, depth 2 meters, Eto tube runner ejected with mine gear - Crash dive. Running time 127 seconds - 1900 meters. Hit center." (Eto = Electric torpedo)
Page 8 - 00.36 "Coup de grâce: Stern shot Eto depth 3 meters. Again a tube runner - ejected with the mine gear - running time 30 seconds = 625 meters. Hit center: Steamer sinks immediately."

TypeVIIb and Type VIIc - 1940/1941 - both have performed two stern shots with G7e/Eto

The KTB must be falsified to confuse the enemy

Just kidding, Mittelwaechter! Great find and thanks for sharing!

My guess still is that probably it was considered unpractical in the beginning, but later it turned out to be practical (unpractical according to peace-time regulations, but in war-time possible).

Regards, LGN1

PS: Just a side note: KTBs were in fact sometimes falsified to hide mistakes, e.g., Lemp was ordered to erase all entries concerning the sinking of Athenia from his KTB, see the book "U-Boat Attack Logs" by D. Morgan & B. Taylor.

[Mittelwaechter]

I fully agree to stay alert and doubtful in matters of military/official information made public. We read, watch and hear what we shall read, watch and hear.

Truth in general is a matter of interpretation - and often a matter of secrecy.

[rudewarrior]

Originally Posted by Mittelwaechter

The external reserves were stored dry, so it shouldn't have been a problem to store a G7a FAT or LUT in the deck containers.

I don't know if they did it.

Per the KTB's that I mentioned in the original post, later in the war they listed TI FaT I's in external storage. Granted it was only for Type IXd's, since by then (with the exception of IXd's and IXc's heading to southern waters) they had stopped storing externals (BTW: this was because depth charges were causing the compartments to flood severely changing the buoyancy and trim of the boat, not allied air power per se). IXd's would imply Type IXc's could as well, and I assume Type VII's as well, since the storage compartments seemed to function the same way between the two types. Same implications for the LuT torpedoes.

Originally Posted by LGN1

My guess still is that probably it was considered unpractical in the beginning, but later it turned out to be practical (unpractical according to peace-time regulations, but in war-time possible).

This is kind of aligned with my theory: In combat, you do what you need to kill enemy and survive. If that means you have to put a G7a in place where a bad support point is, you do it. If that means you have to store a G7e in the rear compartment, you do it. And doubly so if the Kaleun says so. So I think this falls under that "practicality" umbrella.

This is based in part on my non-combat service in the 1990's US Army. There were plenty of times I can remember being told to do something that didn't make any sense or wasn't in some manual somewhere that way. I often got to told to do this by a sergeant, and the choices were to do it or do it after I did some push-ups. I chose to avoid the push-ups.

[Mittelwaechter]

Followup:

I stumbled over Topp's KTB - http://www.uboatarchive.net/KTB552-6.htm

Page 1 - 23/24.10.1941

He loaded 2 Atos and 12 Etos into his 552 VII C - and consequently the Atos were to be stored in the deck containers. So 12 Etos were stored inside the pressure hull, in all available tubes and reserve positions - aft as forward - above and under the floor plates.

Every reserve torpedo storage space was accessable for charging/venting Etos as for greasing the drive shaft and refilling compressed air for the gyros and the depth keeping device.

Maybe they had to lift/shift the torpedos around to service the eels stored under the floor plates (+ center forward). But they definitively stored Etos there too.