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Re: Torpedo loadouts?
Posted by: SnakeDoc ()
Date: April 17, 2011 09:54PM

Hansel Wrote:
> I see the Type-II listed here with only a pair of
> reloads, however I recall "Aces of the Deep" (A
> rather detailed & realistic U-Boat sim, for the
> time) portraying the Type-IIs as having three
> spares? Is two spares considered "Normal" with a
> third being an occasional thing, or is it simply
> an error?

This is an error - Vesikko (CV 707) as well as all type II
U-Boats had only two spare torpedoes in forward torpedo room.

> I'm already somewhat familiar with the Type-VII's
> setup of six spares forward, a single spare aft,
> and one torpedo in a stowage cylinder fore and aft
> outside the hull. I understand that later in the
> war the external reload tubes were often left
> empty as they were difficult to utilize when you
> were under constant air attack.
> -Did the addition of the schnorchel force the
> removal of either external reload?

No, according to drawings in "The Type VII U-boat Anatomy of the ship" and
"Vom Original Zum Modell - U-Boot Typ VII" the Schnorchel in lowered position
did extend up to the forward torpedo loading hatch. The external forward torpedo
stowage container was located in front of forward torpedo loading hatch.

> -Did the boats ever carry extra torpedoes
> internally to compensate for this?

No, due to lack of space it could not be done. In forward torpedo room of type VII U-Boats were 6 spare torpedoes - four under deck plates and two on deck plates - see: []
Such arrangement made possible access to spare torpedoes on deck plates and the torpedoes from two top torpedo tubes could be drew out. When the spare torpedoes from deck plates were pulled up - the torpedoes under plates could be services and also torpedoes from bottom torpedo tubes could be drew out.

> -I've been told, but I take it as a rumor, that it
> was somewhat common to carry TWO spare torpedoes
> in the aft room instead of just one, is there any
> truth to this?

I have never met such practise. I do not think it would be true - first -
it would make hard or impossible operating the Main Switchboards, second -
it would make hard or impossible drawing out the torpedo from the aft torpedo tube for maintance purposes.

> -Where was the VIIC/42 to have carried the
> additional two torpedoes?

In Rossler book "The U-Boat" it is written, that comparing to VIIC, the type VII/42 has increased length of 1,54 m (VIIC - 67,10 m) and max beam 6,85 m (VIIC 6,18 m). I suppose that two additional torpedoes had to be carried in upper deck external containers.

> The Type-IX series confuses me the most,
> however...
> -Why does the IX carry only four spares up front
> when the smaller VII carries six?

Well, finally they carried also six spare torpedoes - exactly as on type VII - see below.

> -Did the installation of the schnorchel force the
> removal of any of the external torpedo
> containers?

Yes, if you look at the drawings and see the Schnorchel location and external torpedo containers location, you will see, that two containers had to be removed.
See also: Type IXC Design Study, chapter 11 HULL STRUCTURAL, paragraph 4. Superstructure:
"The superstructure consists of a light frame structure of angles, with a strake of plating riveted along the sides, and plating sections secured by machine screws on deck in the way of the two capstans and the 10 topside torpedo stowage tanks. The remainder of the deck is of wood slatting. Note here that the two forward torpedo stowage tanks on the starboard side have been removed in those vessels equipped with snorkels."

> -Did the Type-IXs ever carry additional torpedoes
> internally fore or aft to compensate for the
> inability to retrieve the external spares?

Yes, see the following reports on the interrogations of survivors:
U-66 (IXC)
4 torpedoes in bow tubes
4 torpedoes under floor plates in forward torpedo compartment
6 mines above floor plates in forward torpedo compartment
2 torpedoes in stern tubes
3 torpedoes above floor plates in stern torpedo compartment
6 torpedoes in upper deck containers.

U-172 (IXC)
On her first, second, third, and fourth patrols, U-172 carried 23 torpedoes, stowed as follows:
4 in tubes in Bow Compartment.
2 on floor plates in Bow Compartment.
4 under floor plates in Bow Compartment.
2 in tubes in Stern Compartment.
3 on floor plates in Stern Compartment.
8 in Upper Deck Containers.

U-111 (IXB )
The U-Boat was said to have carried on this cruise eighteen torpedoes, of which six were in the torpedo tubes, four in the bilges and two on the
floor plates forward, two in the bilges aft, and four in the upper deck containers.

U-511 (IXC)
She carried six torpedoes in her tubes, four spares under and two above the floor plates in the forward compartment and two more spares in
the after compartment, making a total of fourteen; it was stated that the four remaining upper deck containers for torpedoes were empty.

U-856 (IXC/40)
Bow tube No. 1 1
Bow tube No. 2 1
Bow tube No. 3 1
Bow tube No. 4 1
Stern tube No. 5 1
Stern tube No. 6 1
On bow plates 2
Under bow plates 4
On stern plates 2

> -Were the external containers left empty later on
> like the VII's, or did they continue attempting to
> use them?

No, they either were unused or more often removed.
See also BdU KTB, page 330, paragraph VI. General: Provision of upper deck containers:

> -Where did the IXD carry the extra torpedoes?


"Distribution of the 24 torpedoes on U-177's second patrol was given as follows:
Bow tubes - 4.
Below plates, forward - 4.
On plates, forward - 2 (1 port, 1 starboard).
Stern tubes - 2.
On plates, aft - 2 (1 port, 1 starboard).
Upper deck containers - 10."

> Finally, for all of the boats with external
> stowage, what type of torpedo was most common for
> external stowage? I recall that "Aces of the
> Deep" depicted ONLY T-1/G7a steam torpedoes in
> external stowage at any/all times of the war. I
> would imagine that battery powered torpedoes might
> be problematic if they were in an area that made
> them hard to maintain?

That's right - in external containers were carried only G7a torpedoes (I have read somewhere - without warheads or fuses).



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Subject Written By Posted
Torpedo loadouts? Hansel 04/10/2011 04:21AM
Re: Torpedo loadouts? SnakeDoc 04/17/2011 09:54PM
Re: Torpedo loadouts? Ken Dunn 04/17/2011 11:27PM
Re: Torpedo loadouts? Hansel 04/18/2011 04:22AM
Re: Torpedo loadouts? Ken Dunn 04/18/2011 01:44PM
Re: Torpedo loadouts? SnakeDoc 04/19/2011 06:02AM
Re: Torpedo loadouts? streetdoc911 05/15/2011 01:16AM
Re: Torpedo loadouts? Jerry and Charla Mason 05/15/2011 02:19PM
Re: Torpedo loadouts? streetdoc911 05/15/2011 03:42PM
Re: Torpedo loadouts? Maurice Eldridge 03/02/2019 12:26PM
Re: Torpedo loadouts? Ken Dunn 03/02/2019 01:17PM
Re: Torpedo loadouts? Maurice Eldridge 03/02/2019 03:01PM
Re: Torpedo loadouts? Jerry and Charla Mason 03/02/2019 07:12PM
Re: Torpedo loadouts? Maurice Eldridge 03/03/2019 11:14AM
Re: Torpedo loadouts? Ã…kerberg 04/18/2011 07:04AM

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