A U-Boat VIIc/41 Question

[ravenvv]

Ok this may sound like a stupid question but bear with me. I have seen ‘something’ on the bow of some WW2 subs; it looks like a T on the bow. Now I assume this is a rotating form of a hydrophone. My question (assuming that I have not gotten any thing to badly wrong so far) was this on U-Boat type VIIc/41s, I have seen models with them on the bow, but I have never seen any pic of real U-boat (VIIc41) with one. I have seen VIIc U-boats with them but not VIIc41s?

Thanks
Toph

[don prince]

Hi RavenVV,

Jeff would be the

Hi RavenVV,

Jeff would be the better one to respond. But one reason I could see for there not being the rotating sensor on the deck would be because the Type VIIc/41s had the sensor balcony located under the bow of the U-Boat. They increased the number of sensors and most likely gave better information about opponents in the area.

Regards,
Don_

[hakkikt]

What you mean is the

What you mean is the Kristalldrehbasisgerät (KDB), and you are right, it is a rotating array of hydrophones. It was used less and less towards the end of the war because it was only useful at low speed and susceptible to depth-charging.

It was to be replaced by the Balkongerät (balcony device), an almost circular array of hydrophones under the bow, but that was installed in only a few Type VIIC/41s. Among them U 1105 by the way, the boat with the Alberich anechoic rubber coating.

[JWLaRue]

What you mean is the

What you mean is the Kristalldrehbasisgerät (KDB), and you are right, it is a rotating array of hydrophones. It was used less and less towards the end of the war because it was only useful at low speed and susceptible to depth-charging.

It was to be replaced by the Balkongerät (balcony device), an almost circular array of hydrophones under the bow, but that was installed in only a few Type VIIC/41s. Among them U 1105 by the way, the boat with the Alberich anechoic rubber coating.

That agrees with the information that I've read. Though I cannot find specific references that state that the KDB was *not* installed (though not used) even in the late war boats. The KDB had 6 sound receivers mounted in the cross bar of the 'T' that was manually rotated in order to determine the direction for a sound contact. The sound receivers were the same type of receivers as used in the Gruppenhorchgerät, which were the 11 receivers clustered around each bow plane in an arc.

Also, the same Balkon Gerät was part of the standard install on the Type XXI's.

-Jeff

[sam reichart]

What you mean is the

What you mean is the Kristalldrehbasisgerät (KDB), and you are right, it is a rotating array of hydrophones. It was used less and less towards the end of the war because it was only useful at low speed and susceptible to depth-charging.

It was to be replaced by the Balkongerät (balcony device), an almost circular array of hydrophones under the bow, but that was installed in only a few Type VIIC/41s. Among them U 1105 by the way, the boat with the Alberich anechoic rubber coating.

That agrees with the information that I've read. Though I cannot find specific references that state that the KDB was *not* installed (though not used) even in the late war boats. The KDB had 6 sound receivers mounted in the cross bar of the 'T' that was manually rotated in order to determine the direction for a sound contact. The sound receivers were the same type of receivers as used in the Gruppenhorchgerät, which were the 11 receivers clustered around each bow plane in an arc.

Also, the same Balkon Gerät was part of the standard install on the Type XXI's.

-Jeff

Also standard on the XXI's little brother, the Type XXIII.