Technology and Operations
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Re: Diving sequence
Posted by:
SnakeDoc
()
Date: June 09, 2010 06:31PM
Hello
Briefly - at this moment I do not have enough time to write it fully:
While the boat is cruising on the surface, is driven by Diesel engines. Flood valves (Kingstons) at the bottom of the main ballast tanks and bow and aft buoyancy tanks (Wasserdicht Heck/Back) vents are open. The boat is trimmed after previously done test/trim diving. The crew is on their stations, crew off duty is in their quarters.
When the "Alarm" is ordered, the helmsman in the conning tower turns on the alarm bell, yell "Alarm". The regulations emphasize that each crew member should repeat "Alarm" order loud in case of failure of the alarm bell, flashing lights and general noise.
The helmsman sets the "Diving" ("Tauchen" ) order on the Bb and Stb Machine Order Telegraph Transmitter. Then the crew in Diesel Engines and Electric Motors Room switches drive to electric motors and answers the order "All ahead".
Diesel engines are turned off, Diesel engine clutches are disengaged, all induction air and exhaust valves are closed. The bow diving planes are "hard down", aft - in zero position.
The LI beside of indicating installation should ask if the Diesel Engine Room is ready to dive. The indicating installation has lamps, which signals if all holes in pressure hull are closed.
When LI receives the notification that Engine Room is ready, he reports it to the Commander ("Ist Klar" ). Then Watch Officer reports closing Conning Tower hatch ("Ist zu" ). The Commander orders "Flood" ("Fluten" ), the LI repeats order.
The ballast tanks vents are opened - the No 1 MBT vent when LI orders "Eins". The crew in Control Room reports numbers of the MBT, which vents are already opened.
The LI reports that all vents are opened. The Commander orders - "Depth XX meters", LI repeats order and passes it to all compartments.
When MB Tanks are flooded, the Diesel Engines and Electric Motor Rooms accomplish full dive readiness and report it to LI: "Hinterschiff ist
tauchklar". They are controlling the water pressure in cooling system and tightness of the exhaust system.
Meantime the boat inclines - the upper deck starts submerge. The angle of the inclination should be adjusted in such way, that upper bottom of the Bridge and Stern submerge at the same time.
This angle should be:
- type II, VII: 8 - 15 deg
- type IXC, IXD, XB, XIV: 7 - 12 deg
After reaching the 20 meters, the boat trim is adjusted to 15 - 30 deg - to faster dive.
If the boat is equipped in Negative Tanks (Untertriebszelle), there are few more operations. During surfaced cruise these tanks are flooded. When the "Alarm" is ordered, after opening the MBT vents the LI orders blowing the Negative tanks ("Ausdrucken" ). The best depth to blow is 8 - 12 m. During blowing the water level meters are observed to close flood valves, when tanks are empted.
Written based on: "Tauchvorschrift fur Unterseeboote (U-Boots-Tchvschr.), Berlin 1943, Oberkommando der Kriegsmarine, M. Dv. Nr. 381
If you've got any question, go ahead
--
Regards
Maciek
Briefly - at this moment I do not have enough time to write it fully:
While the boat is cruising on the surface, is driven by Diesel engines. Flood valves (Kingstons) at the bottom of the main ballast tanks and bow and aft buoyancy tanks (Wasserdicht Heck/Back) vents are open. The boat is trimmed after previously done test/trim diving. The crew is on their stations, crew off duty is in their quarters.
When the "Alarm" is ordered, the helmsman in the conning tower turns on the alarm bell, yell "Alarm". The regulations emphasize that each crew member should repeat "Alarm" order loud in case of failure of the alarm bell, flashing lights and general noise.
The helmsman sets the "Diving" ("Tauchen" ) order on the Bb and Stb Machine Order Telegraph Transmitter. Then the crew in Diesel Engines and Electric Motors Room switches drive to electric motors and answers the order "All ahead".
Diesel engines are turned off, Diesel engine clutches are disengaged, all induction air and exhaust valves are closed. The bow diving planes are "hard down", aft - in zero position.
The LI beside of indicating installation should ask if the Diesel Engine Room is ready to dive. The indicating installation has lamps, which signals if all holes in pressure hull are closed.
When LI receives the notification that Engine Room is ready, he reports it to the Commander ("Ist Klar" ). Then Watch Officer reports closing Conning Tower hatch ("Ist zu" ). The Commander orders "Flood" ("Fluten" ), the LI repeats order.
The ballast tanks vents are opened - the No 1 MBT vent when LI orders "Eins". The crew in Control Room reports numbers of the MBT, which vents are already opened.
The LI reports that all vents are opened. The Commander orders - "Depth XX meters", LI repeats order and passes it to all compartments.
When MB Tanks are flooded, the Diesel Engines and Electric Motor Rooms accomplish full dive readiness and report it to LI: "Hinterschiff ist
tauchklar". They are controlling the water pressure in cooling system and tightness of the exhaust system.
Meantime the boat inclines - the upper deck starts submerge. The angle of the inclination should be adjusted in such way, that upper bottom of the Bridge and Stern submerge at the same time.
This angle should be:
- type II, VII: 8 - 15 deg
- type IXC, IXD, XB, XIV: 7 - 12 deg
After reaching the 20 meters, the boat trim is adjusted to 15 - 30 deg - to faster dive.
If the boat is equipped in Negative Tanks (Untertriebszelle), there are few more operations. During surfaced cruise these tanks are flooded. When the "Alarm" is ordered, after opening the MBT vents the LI orders blowing the Negative tanks ("Ausdrucken" ). The best depth to blow is 8 - 12 m. During blowing the water level meters are observed to close flood valves, when tanks are empted.
Written based on: "Tauchvorschrift fur Unterseeboote (U-Boots-Tchvschr.), Berlin 1943, Oberkommando der Kriegsmarine, M. Dv. Nr. 381
If you've got any question, go ahead
--
Regards
Maciek
| Subject | Written By | Posted |
|---|---|---|
Diving sequence
|
Jordanitp | 06/08/2010 02:04AM |
|
Re: Diving sequence
|
SnakeDoc | 06/09/2010 06:31PM |