Hi Gentlemen,
I have not been here for a some time, so I'll try to answer for some questions in one post.
Interesting stuff Maciek, details like this won't make it into the first version of my game but I will try to implement it into the later main version which should be much more complex.
Nonsense It's much easier to do a lot of this now, at least the basic stuff.
Where can I find info how quickly the different tanks can be filled and how quickly they can be blown?
We were more concerned about f.i. diving time rather than surfacing time. Crash diving required a very well trained crew. With normal preparation and a trained crew you could manage 30 seconds which is pretty fast compared to other similar submarines at that time.
My (hopefully not totally idiotic) calculation for the required time to flood the MBT below the command room (when no other tanks are flooded and the boat can still float on the surface) is something like 11.64 seconds
Do you think that could be OK?
When I use the standard leak formula the result is that the 47 cubic metres of this tank could be theoretically flooded within 2.29 seconds (if the tank would be completely open on top instead of having 2 valves for the air to leave) when the "leak" of a comparable size is at a depth of 4 meters.
My calculation takes the leaving air through the 2 vents into account that's why it's much slower. But 10 seconds fits with some numbers I have read yesterday about flooding a MBT on a "Tauchboot" compared to real modern submarines which flood slightly slower.
Shouldn't the MBTs already have completely filled when you've reached pericope depth? I think the positive buoyancy would be too strong to go that deep that fast otherwise. But that's just my guess…
I have also used some standard formulas for a leak into the tank with opened top. As a result I had about 10 seconds for flooding all three main ballast tanks. Taking into the consideration the diameter of the vent ducts, I think it fits into the practical times of achieving periscope depth.
In the german original version of the manual I've found the sentence:
"Die Regelzellen sind angeschlossen an die Fluteinrichtung in der Zentrale…"
which means:
"The regulating tanks are connected to the flood installation in the command room"
But the english translation says:
"The regulating tanks are connected to the drainage installation in control room"
…in the description of the Torpedo compensating tanks Maciek used "drainage installation" for the word "Lenzleitung" which is correct (and the opposite of a "Fluteinrichtung")
Literally translation of the word
Fluteinrichtung is
flood installation as you said. I have translated it as
drainage installation, because in other parts of manual, this system is called either
Flut- und Lenzeinrichtung or (more common)
Lenzeinrichtung and I tried to keep consistency. This
Flut- und Lenzeinrichtung was used to drain bilges and tanks or to flooding regulating tanks, as Tore explained.
As Tore said, the British English term is rather bilge system or bilge pump rather than (as in American) drain/drainage system. You can easily see this difference while reading British report and ONI report on HMS Graph (or American reports on type IXC and XXI U-Boats). I used rather American naval terms.
The torpedo compensating tanks… in the german version of the manual they write "Die Torpedozellen nehmen das Wasser für den Gewichtsausgleich der Torpedos und Minen sowie das Umhüllungswasser auf" - Maciek forgot to translate the word "Umhüllungswasser" in the english version: "The torpedo compensating tanks are flooded to compensate for the weight of a launched torpedo or mine." - this word is pretty tricky to translate it's like "surrounding water", I guess they mean the water used when flooding the torpedo tubes?
Right you are, my mistake.
Have you seen my document on torpedo tubes?
http://www.ubootwaffe.pl/en/u-boats/equipment/torpedo-tubes-of-german-u-boatsTore, do you know what diameter the lines of the compressed air blowing installation to the tanks had (or the inlet openings for that in the tanks itself? Or was that somehow connected to the air vents of the tank?)… I need that information to calculate the time necessary for blowing tanks at a given depth
The inner and outer diameter of blowing lines are 17 and 20 mm respectively.
--
Regards
Maciek