Too fast....??

Bulkhead · 03-19-08, 07:02 PM

Hi. I started a german career with the Type-XVIII. I did a test dive just to see how it worked, and i noticed the walter turbine witch is a kind of fuel engine to use when submerged. The ting is when i hit the "ahed flank" the sub reached a speed of 25 knots. As far as i know these subs where fast submerged, about 17-18 knots. But 25??? Honestly, the sub was flying away under water.
Was the hydrogenperoxide syclus that efficient?

LukeFF · 03-19-08, 07:02 PM

Do some reserch, and you'll get your answer.

Bulkhead · 03-19-08, 07:11 PM

Oh....sorry to disturb the peace..

Ducimus · 03-19-08, 07:15 PM

http://www.uboat.net/types/walter.htm

Bulkhead · 03-19-08, 07:22 PM

thanks

. I stay away

Zantham · 03-19-08, 07:25 PM

The Type VII and IX subs were really more like boats that happened to be able to go under water for a while and come back up again. As such, they were designed to operate better on the surface than submerged.

The Type XVIII and XXI on the other hand were designed to be a true submarine; they operated much more efficiently submerged than the previous uboat designs. Hence they could travel faster submerged than the VII and IX.

The most important difference between the XVIII (which was never actually built) and the XXI was the XVIII had large tanks full of H2O2, whereas the XXI used this space for more batteries.

The diesel motors on the XVIII were capable of producing about 4000 - 4400HP, and usable only on the surface. To go full speed submerged with a snorkel on the diesel would rip the snorkel right off.

The Walther turbine, however, generated close to 4x the power of the diesel, about 15,000HP estimated. This engine also had the benefit of working surfaced or submerged. So combine a hull designed to operate under water with a 15,000HP engine... you can see where 25kts might have really been a possibility. Of course, no one knows the true speeds since one was never built.

The XXI relied on the sheer volume of its high-capacity batteries to attain its 17kt+ speeds under water. Obviously the batteries could not generate 15,000HP so it would not have had quite as much thrust underwater as the Walther turbine might have had.

Bulkhead · 03-27-08, 01:56 PM

Quote:

Originally Posted by LukeFF

Do some reserch, and you'll get your answer.

Why did you reply like this? Too prove that you are smarter than me and many more? I dont see why you replying if you have no more too say. I am not that good in net and research, sorry. This is why i keep bailing out of forums. Some one just cant stand some more or less stupid questions. Well, news for you, I am not that smart. (not remind me, i know it already)
Zantham:thanks, very cool

You dont have to make it hard, if you want me out say so...Bye-bye

Friedmann · 03-28-08, 03:44 PM

Quote:

Originally Posted by Bulkhead

Quote:

Originally Posted by LukeFF

Do some reserch, and you'll get your answer.

Why did you reply like this? Too prove that you are smarter than me and many more? I dont see why you replying if you have no more too say. I am not that good in net and research, sorry. This is why i keep bailing out of forums. Some one just cant stand some more or less stupid questions. Well, news for you, I am not that smart. (not remind me, i know it already)
Zantham:thanks, very cool

You dont have to make it hard, if you want me out say so...Bye-bye

Don't take it personally, he is just trying to raise his post count.

03-19-08, 07:02 PM	#1
Bulkhead 中国水兵 Join Date: Sep 2007 Location: Norway, Hordaland Posts: 279 Downloads: 153 Uploads: 0	Too fast....?? Hi. I started a german career with the Type-XVIII. I did a test dive just to see how it worked, and i noticed the walter turbine witch is a kind of fuel engine to use when submerged. The ting is when i hit the "ahed flank" the sub reached a speed of 25 knots. As far as i know these subs where fast submerged, about 17-18 knots. But 25??? Honestly, the sub was flying away under water. Was the hydrogenperoxide syclus that efficient? __________________ KHJ

03-19-08, 07:02 PM	#2
LukeFF Silent Hunter Join Date: Apr 2005 Location: Riverside, California Posts: 3,610 Downloads: 41 Uploads: 5	Do some reserch, and you'll get your answer. __________________ ROW Sound Effects Contributor RFB Team Leader

03-19-08, 07:11 PM	#3
Bulkhead 中国水兵 Join Date: Sep 2007 Location: Norway, Hordaland Posts: 279 Downloads: 153 Uploads: 0	Oh....sorry to disturb the peace.. __________________ KHJ

03-19-08, 07:22 PM	#5
Bulkhead 中国水兵 Join Date: Sep 2007 Location: Norway, Hordaland Posts: 279 Downloads: 153 Uploads: 0	thanks . I stay away __________________ KHJ

03-19-08, 07:15 PM	#4
Ducimus Rear Admiral Join Date: May 2005 Posts: 12,987 Downloads: 67 Uploads: 2	http://www.uboat.net/types/walter.htm

03-19-08, 07:25 PM	#6
Zantham 中国水兵 Join Date: Feb 2007 Location: Canada Posts: 283 Downloads: 63 Uploads: 1	The Type VII and IX subs were really more like boats that happened to be able to go under water for a while and come back up again. As such, they were designed to operate better on the surface than submerged. The Type XVIII and XXI on the other hand were designed to be a true submarine; they operated much more efficiently submerged than the previous uboat designs. Hence they could travel faster submerged than the VII and IX. The most important difference between the XVIII (which was never actually built) and the XXI was the XVIII had large tanks full of H2O2, whereas the XXI used this space for more batteries. The diesel motors on the XVIII were capable of producing about 4000 - 4400HP, and usable only on the surface. To go full speed submerged with a snorkel on the diesel would rip the snorkel right off. The Walther turbine, however, generated close to 4x the power of the diesel, about 15,000HP estimated. This engine also had the benefit of working surfaced or submerged. So combine a hull designed to operate under water with a 15,000HP engine... you can see where 25kts might have really been a possibility. Of course, no one knows the true speeds since one was never built. The XXI relied on the sheer volume of its high-capacity batteries to attain its 17kt+ speeds under water. Obviously the batteries could not generate 15,000HP so it would not have had quite as much thrust underwater as the Walther turbine might have had.