REQUESTING help for a question

[richardphat]

Ok, I argue with someone on another forum.
He said an engagement between two subermeged SUB IS impossible in WW2 and in real life.
So the question is:
Is it possible for submarines from WW2 engaging another sub while submerged in real life?

True, i am not informed if there was a fight. Nothing has proven this case is impossible.
Nothing has proven this is possible. Well until now, i didn't find any source which prove me that. Unless, I have been smacking my head.
But he kept using his talent of sophist to try and convince me. What a tough guy.

[fatty]

It is possible, indeed it did happen: Brit sub HMS Venturer sank U-864 on 9 February 1945 while both were submerged after a 3-4 hour engagement. That does not mean it was common. In fact, this case is the only known instance in naval warfare history where one submerged submarine sank another submerged submarine.

[richardphat]

THX god d***** I love you. Now got to show him that.

[Fincuan]

Here's another one for you, dating back even further. It is from the book Submarines(1982) by Antony Preston(sic). The excerpt is from the WW1 part of the book, where the author mentions a ghost story involving either the U-65 or UB-65. I wasn't able to find a good source for this on the internet, so here goes how it's in the book. Note that according to the most recent knowledge UB-65 wasn't lost at this incident.

Originally Posted by Submarines

UB.65 sailed from the Heligoland Bight on 2 July 1918(still under the command of [Kapitänleutnant] Scheele) avoiding a torpedo from British boat G.6 on the way, but her periscope was sighted off the Fastnet rock by the American submarine AL.2 at a distance of only 80 yards. Lieutenant Foster was maneuvering to attack when he heard an explosion ahead of the U-Boat, followed by the noise of fast-running propellers and then silence. The assumption by modern authorities is that UB.65 had fired a torpedo(whether at AL.2 or another target is open to question) which exploded prematurely as it left the tube. As both submarines were submerged during the encounter it is highly unlikely that Foster saw a ghostly figure and his report makes no mention of it.

Just out of curiosity, did the person you're arguing with state why an engagement between two subs would be impossible?

[Stealth Hunter]

Was this by chance related to U-571?:hmm:

[kurtz]

I know I'm arguing against the evidence but I don't see how a submarine can target another submerged submarine;

Would the submerged boat be able to open torpedo doors?

What's the max depth a torpedo can run at?

Would the hydrophones give an accurate 3D fix?

On the other hand, acoustic torpedos which did operate in three dimensions were dropped from aircraft to destroy subs so maybe, if they were carried?

[SteamWake]

Originally Posted by kurtz

I know I'm arguing against the evidence but I don't see how a submarine can target another submerged submarine;

Would the submerged boat be able to open torpedo doors?

Yes up to 100 feet deep or so.

What's the max depth a torpedo can run at?

Depends on the type. I have been unable to find definative numbers on 'how deep' but I would assume they could run plenty deep enough. If your shallow enough to open the doors that is. Besides what if the target is at periscope depth? Then you would only need 10 feet or so.

Would the hydrophones give an accurate 3D fix?

Of course, conditoins permitting, passive could give a good estimate as to bearing and speed, active could give a solid number on range, only elements missing are AOB and depth. Given you have the other data you could make a good guess on that too. However bear in mind your target would be doing about 6 to 8 knots at best making it a pretty easy target.

On the other hand, acoustic torpedos which did operate in three dimensions were dropped from aircraft to destroy subs so maybe, if they were carried?

Cuties could have been used but not without risk, furthermore I dont know if the target would have a large enough noise signature for the accoustic (of that eara) to find. Perhaps if they were standing on at flank :hmm:

[Raptor1]

Could the Cuties change the depth they were in? (I know the FIDOs they were based on could, but the Cuties were ASuW weapons rather than ASW)

[SteamWake]

Originally Posted by Raptor1

Could the Cuties change the depth they were in? (I know the FIDOs they were based on could, but the Cuties were ASuW weapons rather than ASW)

Probably not though I dont know for sure, Im assuming they were like most torpedoes of that eara where the depth was pre-set.

[Raptor1]

That would make them practically useless as ASW weapons as the target could just dive under them (Unless the target was either unaware of you, or you have an enormous amount of luck (As was the case with HMS Venturer))

[breadcatcher101]

There was an American sub during WW2 that sunk a submerged Japanese sub with a magnetic torpedo. The torpedo exploded when it passed over the hull of the I boat rather than under as it would do with a surfaced vessel. I think the American sub was surfaced at the time, though.

(Info from the book "Silent Victory" by Clay Blair.)

[bookworm_020]

Originally Posted by Stealth Hunter

Was this by chance related to U-571?:hmm:

Don't mention that evil in here It could start some long term flame wars!

or you have an enormous amount of luck (As was the case with HMS Venturer)

They missed with the first three torps, but got luck on the last.

[August]

Originally Posted by bookworm_020

Don't mention that evil in here It could start some long term flame wars!

Best part of that movie was John Bon Jovi getting hit with that flying hatch cover.

[CaptainHaplo]

There was more than one encounter between submerged submarines in WWII. Most were unsuccessful for both sides. However, as to how - it works the same way that modern subs target and track each other. Sure the technology is much advanced - but its still math. Once you have a bearing, and speed (which you can get from screw speed) then its a matter of working out course and range. Depth can also be determined to a point using the sound signal - and its a good bet that a target sub would be at periscope depth or close to it. Course and range can be gotten by bearing changes vs time with a known speed. All this could be done passively like it is now - or you can warn the target and ping it (though in a war this would be very unwise).

OK - you can get course, range and bearing - with those three you can extrapolate the AOB. With speed you have a solution. All without ever having to SEE the target. Since a submerged sub in WW2 wouldnt normally be using high speed while submerged (unless snorkeling - which takes the depth question out entirely) you can bet you would have some time to work out the details and squeeze off a fair shot if you were lucky enough to have a decent position and hear the target coming.

[Fincuan]

Originally Posted by CaptainHaplo

Since a submerged sub in WW2 wouldnt normally be using high speed while submerged (unless snorkeling - which takes the depth question out entirely)

Not even then, the speed limit when snorkeling was pretty low. Many sources seem to put it around six knots, any faster and you'd lose the snorkel. Snorkeling was and is also a very noisy job.

After learning some TMA with only the bearing information available in Dangerous Waters, where it's practically the only way to do it and survive, I've applied the same methods to SH4 with the help of Mobo(which has a simple TMA function included). It works quite well, even though it's rarely necessary given the AIs inability to detect active sonar pings. You can always ping without fearing the results, while in DW you'd maybe do it once to confirm the solution before lobbing an ASROC at the target. Then you'd have to leave the scene and fast since a torpedo would certainly be inbound. They didn't of course have tools like Mobo available during WW2, but they did have other means of achieving the same result.