Don,
Is the Regulating and RFO tank 1 open to the Sea? A while back I had the understanding that this tank had fuel oil floating on top of water and as the oil was used it was replaced with Sea water (a Self Regulation tank). If so, then where is the opening for the sea water to enter the regulating and RFO tank 1?
Regulating and FRO Tank 1 (
Regebunker 1) was not self-compensated tank. It was pressure-proof, flooded and emptied by means of the flooding and drain manifold (
Flut und Lenzverteiler).
It looks like there are 3 blowing distributor systems
1. the Main Blowing Distributor (Plate 17)
2. the Exhaust Blowing Distributor (Plate 16)
3. the Emergency Blowing Manifold (Plate 16 and Plate 17)
Q1. is this correct. where are they located in the control room
Q2. it looks like the Exhaust Blowing Distributor only affects D1 through- D5
Q3. It looks like the other 2 blowing distributors affect all tanks except Regulating Tank 2 because this tank has no flood valve and has to be pumped???
Only main blowing manifold (compressed air) is located in the Control Room - right to the aft diving plane operator station.
The exhaust blowing manifold is outside the pressure hull - (more or less) over the main blowing manifold. Through the pressure hull are passing valve spindles, and only hand wheels are available for operation in the control room. These are eight, small, red hand wheels at the control room ceiling, over the main blowing manifold.
The emergency blowing manifold would be also located outside the pressure hull - in front of the conning tower, in the magnetic compass casing. Would be - because in late-war front going U-Boats it was not fitted (U-995 was not equipped with that). In the HMS Graph report this manifold is mentioned, but from survivors interrogation reports seems, that this manifold was fitted only for the time of U-Boat crew training (that is, when the vessel operated on the relative shallow waters of the Gdansk Bay or similiar).
Here is short discussion:
http://models.rokket.biz/index.php?topic=921.msg12001#msg12001The exhaust blowing manifold indeed affects only ballast tanks.
If there is a down U-boat and a diver hooks up the two lines in order to bring the U-boat to the surface, then all effort is for nothing if no one is conscious and able to open the Tide valves on D2, D3 and D4, and open the hull valves on ALL the other tanks???
All blowing valves of the emergency blowing manifold were located external - so available for diver. The flood valves of the ballast tank 3 was almost never closed when U-Boat was at sea. If the buoyancy gained by blowing all three main ballast tanks was not sufficient to rise the boat, the other measures had to be taken.
To know, how emergency blowing manifold could like, you can sea this diagram:
http://dreadnoughtproject.org/plans/KM_Uboot_Type_II_1934//bergungsplan_100dpi.jpg--
Regards
Maciek