General Discussions
This is the place to discuss general issues related to the U-boat war or the war at sea in WWII.
Re: U802 was the fwd deck modified for faster diving. Help please.
Posted by:
ARANTALES
()
Date: March 28, 2018 03:10PM
The TNA-record wirth reference ADM281/143 has in topic 30 some comments on the "waisting" of the forward deck of Type IX uboats, based on experienxze with U1232 (Type IXC40).
Dobratz, CO U1232, commented that with the normal casing the bubble had to be kept at about 1 1/2° aft when snorkelling, and the boat about 9 tons heavy when doing this in a heavy sea.
When the boat had to dive deep in an emergency, this 9 tons plus a ton for the compression of the hull had to be pumped out.
With the superstructure waisted, the former 9 tons were reduced to 1 1/2 tons, "an important consideration in being able quickly to slow down when diving deep".
The waisting, Dobratz continues, also had the advantage of improving the dryness of the bridge and a quicker recovery of the bow when plunging into a heavy sea.
This in addition to the main purpose of the waisting: reducing the diving time.
Chr.Aschmoneit remarks that the waisting reduced the diving time of the boat by 3 to 4 seconds, that only a very few uboats received the waisted deck and that the same results could be achieved with larger holes in the superstructure.
Best regards,
Walter
Dobratz, CO U1232, commented that with the normal casing the bubble had to be kept at about 1 1/2° aft when snorkelling, and the boat about 9 tons heavy when doing this in a heavy sea.
When the boat had to dive deep in an emergency, this 9 tons plus a ton for the compression of the hull had to be pumped out.
With the superstructure waisted, the former 9 tons were reduced to 1 1/2 tons, "an important consideration in being able quickly to slow down when diving deep".
The waisting, Dobratz continues, also had the advantage of improving the dryness of the bridge and a quicker recovery of the bow when plunging into a heavy sea.
This in addition to the main purpose of the waisting: reducing the diving time.
Chr.Aschmoneit remarks that the waisting reduced the diving time of the boat by 3 to 4 seconds, that only a very few uboats received the waisted deck and that the same results could be achieved with larger holes in the superstructure.
Best regards,
Walter
| Subject | Written By | Posted |
|---|---|---|
U802 was the fwd deck modified for faster diving. Help please.
|
Colin Gibson | 01/15/2018 12:37PM |
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Re: U802 was the fwd deck modified for faster diving. Help please.
|
Richard Cole | 01/21/2018 02:14AM |
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Re: U802 was the fwd deck modified for faster diving. Help please.
|
ARANTALES | 03/28/2018 03:10PM |