Keel construction detail

[bianco64squalo]

Hi everybody,
are there some drawings showing, in detail, how was the U-Boat Type VII keel constructed ? I'm very interested in that question...
Another question: what are, exactly, the two fairings present on the hull near bow ( see the posted fdrawing ).
Thanks in advance.
Filippo

[tore]

Hi Filippo.
Below is my image of the keel cross section. The keel was sometimes used as a cargohold, welding the " hatches" water/pressure tight. The blisters fairing on your image are a kind of ejectors to facilitate a proper draining of the very narrow freeflood aerea between the bow casing and the pressurehull as you shall see on my image below.
Tore

[bianco64squalo]

Thanks Tore,
are you saying that those fairings had an hole on the back side ? I never saw these holes on a photo....

[bianco64squalo]

I saw that many clever modelers didn't open those fairings, ando so: what kind of draining holes could they were, if closed ?

[tore]

Filippo.
I don`t think you should look at the modellers solution to the blisters. At the very narrow freeflood space where the light bowcasing is welded to the pressure hull you get air pockets which have to be vented, a suction is obtained by placing streamlined blisters under the surface having an opening in the aft end. When the submarine is going ahead a suction is created in the difficult narrow area removing the airpockets prior to the diving.
Tore 

[bianco64squalo]

Thanks Tore,
excellent explanation....as usual, the devil is in details....I'll ask to you many, many questions, during my U-552 Trumpeter building...I think there are not so many experts on U-Boat construction's details in internet, so thanks in advance for your future help....
And now: do you like the deck gun I made ? I had received no opinions in this site....
Cheers.
Filippo

[tore]

Sorry Fillippo, I am a marine engineer and don`t know much about guns.
Tore