submarine speed

Re: submarine speed

feeds@yuku.com (schudak) — Fri, 18 Apr 2008 00:22:33 GMT

>25 knots?! On one of those little Baltic boats? I wouldn't have thought that possible.

Well, perhaps memory fails me with the top speed. Its twenty years ago
I am just sure that the Spanish certainly did not believe that it was possible back then, too.

The description for SSKs (at least our old Baltics) as "mobile mines" is pretty fitting, imho, though that...

Re: submarine speed

feeds@yuku.com (drunknsubmrnr) — Thu, 17 Apr 2008 21:41:21 GMT

Bad scope drill...it shouldn't have been up for more than 10 seconds. The Periscope Assistant is supposed to help with that.

Basically, the PA's job (he's usually the Steward) is to turn the scope to the correct bearing as it's coming up out of the well, track the amount of time it's been up and knee the scope handler in the nuts if he leaves it up too long.

Never had a problem with the scope being up too long on any boat I sailed on.

Kevin

Re: submarine speed

feeds@yuku.com (Gunnersmate04) — Thu, 17 Apr 2008 21:14:48 GMT

....in wargames with a ASROC. You may ask yourself how a 25 year old DDG of the ADAMS Class which was built primarily for AAW sank a super quiet 688 Class...it was the USS HOUSTON to be exact, well, let me tell you.

After getting "Sunk' every night- 3 nights straight by the HOUSTON, a SN Messcrank noticed that one of the bags of trash he just threw over was following us. The bag had gotten stuck on the sub's periscope and they never knew it. So the Skipper ordered a...

Re: submarine speed

feeds@yuku.com (FreeloaderUK) — Thu, 17 Apr 2008 01:13:16 GMT

HMS Venturer sank a german U-boat while both subs were submerged- the only time it ever happened in WW2. the Venturer went after the u-boat after intelligence picked up signals that it was carrying top secret stuff to Japan. so the Venturer chased the u-boat but hoped it would surface so it could sink it but the u-boat went deeper & zig-zagged. so after a while the captain of the venturer decided to sink the u-boat. they mathematically worked out an underwater firing solution (which is...

Re: submarine speed

feeds@yuku.com (drunknsubmrnr) — Wed, 16 Apr 2008 20:42:58 GMT

"I remember reading that the generator capacity of the ww1-era R-class boats was insufficient for them to actually charge their batteries while underway. "

I think they were able to trickle charge, but it would have taken days to put a full charge in.

A lot of submarines were sunk by other submarines in WWI and WWII. I can't recall any of the sinkings where the attacker was surfaced, although there was one case in WWII where both attacker and target were...

Re: submarine speed

feeds@yuku.com (emc) — Wed, 16 Apr 2008 20:06:52 GMT

CVA02 wrote:

PMN1 wrote:
The RN WW1 R class were an exception, designed in 1917 as submarine hunter with (according to D K Brown's ' The Grand Fleet) a surface speed of around 9.5kt and a submerged speed of 12.5 - 15kts.

Question on this, given the RN had already shown what was possible, why did no-one else copy this?
...

Re: submarine speed

feeds@yuku.com (CVA02) — Wed, 16 Apr 2008 18:55:00 GMT

PMN1 wrote:
The RN WW1 R class were an exception, designed in 1917 as submarine hunter with (according to D K Brown's ' The Grand Fleet) a surface speed of around 9.5kt and a submerged speed of 12.5 - 15kts.

Question on this, given the RN had already shown what was possible, why did no-one else copy this?

http://warships1discussionboards.yuku.com/topic/3850?page=1

...

Re: submarine speed

feeds@yuku.com (drunknsubmrnr) — Wed, 16 Apr 2008 17:12:08 GMT

25 knots?! On one of those little Baltic boats? I wouldn't have thought that possible.

We did 18 knots once, but we had to run the batteries in series. That's 1300 V over a nominal 440 V bus. It was pretty exciting though...lots of screaming creaking and groaning, and that was just the crew. Hydrodynamics were really weird too. I had to put the planes 5 to dive just to keep the bow from lifting due to the "wing shape" sonar dome.

Kevin

Re: submarine speed

feeds@yuku.com (schudak) — Wed, 16 Apr 2008 01:01:30 GMT

>modern SSKs usually around 12knots surfaced, 20knots submerged

20?

Reminds me that the Spanish destroyer on whom we used 25+ knots submerged in an exercise some 20 years ago claimed that he was up against two of us, not one :-)

Not sure what the max speed is today, but 20 is far too low.
Anyway, its noisy and drains the battery. You better know when to use it.

Re: submarine speed

feeds@yuku.com (NewGolconda) — Wed, 16 Apr 2008 00:12:27 GMT

IMHO that is one of the widely underapreciated aspects of modern SSK operations in the armchair world. The way a modern SSK needs to run on surface with open hatches to utilise most of its internal combustion horsepower. I know I didnt get it, till Kevin pointed it out.

The other one would be AIP, and the number of SSK's operators who have looked at it and thought, why?

Re: submarine speed

feeds@yuku.com (drunknsubmrnr) — Tue, 15 Apr 2008 23:55:41 GMT

Most boats don't go more than a few knots while snorting because at more than about 5 knots or so, you're draining the battery faster than you're charging it. And no, it's not easy to find a boat while it's snorting unless they're being unusually daft about it.

Kevin

Re: submarine speed

feeds@yuku.com (emc) — Tue, 15 Apr 2008 23:44:33 GMT

taschoene wrote:

BenRoethig wrote:
Most modern diesels are going to spend most of their time of the surface. You need the diesels to charge the batteries and the diesels need air.

Modern diesels have something that most wartime subs lacked -- good snorkels that allow them to run engines at periscope depth, not actually surfaced....

Re: submarine speed

feeds@yuku.com (SubsRUs) — Tue, 15 Apr 2008 23:10:41 GMT

AIP has little to do with submarine maximum speeds. It is used to provide low-speed capability for long periods of time, i.e., to patrol an operational area without surfacing or snorkeling, both of which can be readily detected.

For all non-nuclear submarines, maximum submerged speed is attained by, essentially, "dumping" the battery to the propulsion motor. Endurance at maximum speed is typically one hour or less. Hence,...

Re: submarine speed

feeds@yuku.com (FreeloaderUK) — Tue, 15 Apr 2008 19:08:43 GMT

there's also AIP to consider

Re: submarine speed

feeds@yuku.com (taschoene) — Mon, 14 Apr 2008 19:29:23 GMT

BenRoethig wrote:
Most modern diesels are going to spend most of their time of the surface. You need the diesels to charge the batteries and the diesels need air.

Modern diesels have something that most wartime subs lacked -- good snorkels that allow them to run engines at periscope depth, not actually surfaced. Besides, the indiscretion rate (the ratio of engine run time to battery time) is pretty...

Re: submarine speed

feeds@yuku.com (BenRoethig) — Mon, 14 Apr 2008 18:38:06 GMT

Most modern diesels are going to spend most of their time of the surface. You need the diesels to charge the batteries and the diesels need air.

Re: submarine speed

feeds@yuku.com (FreeloaderUK) — Sun, 13 Apr 2008 09:35:05 GMT

if i remember correctly ww2 subs spent a lot of their time on the surface- a fast submerged speed but slow surface speed may have been handy in some circumstances ie whenuchasing another ship. but for ranged missions- she'd have to come upto the surface a lot.

Re: submarine speed

feeds@yuku.com (bager1968) — Sun, 13 Apr 2008 07:28:34 GMT

A prime driver in sub design throughout history has been range... and until the development of highly efficient & powerful underwater propulsion systems, range was most easily accomplished on the surface (where there is air for the engines to use), so subs were optimised for that function.

The "R" class were analogous to today's SSKs... they were intended to protect the waters around the British Isles (primarily from German subs), so range was almost a...

Re: submarine speed

feeds@yuku.com (PMN1) — Sun, 13 Apr 2008 02:29:12 GMT

Would a higher submerged speed have helped RN and USN subs in their methods of operation?

Re: submarine speed

feeds@yuku.com (PMN1) — Sun, 13 Apr 2008 02:09:23 GMT

The RN WW1 R class were an exception, designed in 1917 as submarine hunter with (according to D K Brown's ' The Grand Fleet) a surface speed of around 9.5kt and a submerged speed of 12.5 - 15kts.

Question on this, given the RN had already shown what was possible, why did no-one else copy this?

http://warships1discussionboards.yuku.com/topic/3850?page=1

submarine speed

feeds@yuku.com (FreeloaderUK) — Sat, 12 Apr 2008 22:52:53 GMT

in ww2 a submarine could achieve around 20knots surfaced, 8knots submerged.

modern SSKs usually around 12knots surfaced, 20knots submerged

SSNs usually around 18knots surfaced, over 25knots submerged

obviously variations are wide.

but what i want to know is- how come subs are slower on the surface than dived? in the past it was the other way round