Torps - Premature explosions?

[cpt_idaho]

Hi,

Yesterday I lined up to shoot at a convoy at a distance of around 2500 yards; after all the needed calculations I fired 4 torps at one of the merchants. However, after 5-10 seconds they blew up, one by one - as if they hit some invisible barrier.

I reloaded the game, thinking that maybe there was too narrow a gap between the torps, so I gave each 5 seconds before I fired another.. with the same effect. They just exploded after 100 meters.

Is it a bug or, lets say, first torp exploded prematurely and caused another explosions?

[tater]

mk 14s prematured a lot in RL. I gather the weather was bad during your attack? Rough seas make them do this more than calmer seas.

[switch.dota]

Question: does the running depth of the torpedo have any impact on the chance to cause premature explosions?

[cpt_idaho]

mk 14s prematured a lot in RL. I gather the weather was bad during your attack? Rough seas make them do this more than calmer seas.
You are right, the weather wasn't good.. but all 4 of the torpedoes exploding in a similar spot? Is it possible that it was some kind of a chain reaction after the first explosion?

[elanaiba]

If the weather is bad, there are big chances they will premature right at the arming distance.

[cpt_idaho]

elanaiba - yeah, seems that that is what has happened.. then switch.dota's question becomes even more important: does the set running depth changes anything?

[nomad_delta]

Question: does the running depth of the torpedo have any impact on the chance to cause premature explosions?

I went ahead & added your question as #13 in my Q&A thread:
http://www.subsim.com/radioroom/showthread.php?p=592858#post592858

I'd already talked about premature detonations a bit in the answers to questions #2 and #9, and as a side-effect of my testing so far I'm 90% certain that weather is the only thing that has an effect on premature detonation chances in the game. Weather does have a huge effect though, as well as distance-to-target, in a sense. Also "wave-state" (weather) is the only factor mentioned in the "torpedoes_us.sim" for premature detonation chances.

I'll try to do some more specific testing to confirm that torpedo running depth doesn't affect prematures, and I'll post my findings there once I'm done.

nomad_delta

[elanaiba]

Yeah, the deeper they go, the lower the chance for a premature.

[nomad_delta]

Yeah, the deeper they go, the lower the chance for a premature.

I stand corrected, then. I think I'll still run some tests just to be sure. I should join the Ubi QA department or something... :D

nomad_delta

[elanaiba]

No, actually I have to stand corrected myself, checked the code and we didn't get around to have depth influence the prematures rate :( Bad memory :( :(

[nomad_delta]

No, actually I have to stand corrected myself, checked the code and we didn't get around to have depth influence the prematures rate :( Bad memory :( :(

No worries, mate. I'm honestly amazed you guys got as many things working as you did during the short period of time you had to work with. There are a million things SH4 does exactly right, but we don't tend to think about those since they just work and we're so immersed in the game. ;)

nomad_delta

[SteamWake]

Yeah, the deeper they go, the lower the chance for a premature.

I stand corrected, then. I think I'll still run some tests just to be sure. I should join the Ubi QA department or something... :D

nomad_delta

They have one ?

[tycho102]

Hi,
Yesterday I lined up to shoot at a convoy at a distance of around 2500 yards

Keep it under 1000 meters and you'll get *much* better results.

On top of that, if you were in the middle of the convoy, loosing both stern and bow tubes, you're going to get better tonnage per patrol. In the middle of the convoy, you're never more than 1km from the nearest ship -- usually arming distance is the problem because boats are usually closing on you when you start firing. And you're safer in the middle of the convoy because the escorts are usually are the perimeter, giving you time to get some depth before the convoy moves much.

[ae4rv]

In real life it was the magnetic exploder that caused prematures, not the sea state. Torpedoes are not generally suseptable to unwanted explosions due to rough handling... :damn:

[elanaiba]

Magnetic detonators may be triggered by movement caused by rough seas.

[nomad_delta]

Magnetic detonators may be triggered by movement caused by rough seas.

Any word/update on getting the Contact/Influence switch to work so we can at least turn off the magnetics and avoid the premature detonations in rough seas? (We would, of course, then be susceptible to contact-duds, but at least those can be mitigated by not firing at 90 degree angles...)

Were you at least able to replicate and see the issue I described about the switch not working?

nomad_delta

[elanaiba]

Yes, my testing so far seems to confirm it, which is very strange since I remember precisely testing it sometime in the past.

I think it won't be hard to fix, the question is when do we get something else out to you guys.

[Deep6]

I think it won't be hard to fix, the question is when do we get something else out to you guys.

Will one of the female skippers please kiss this man! :D

[kv29]

I think it won't be hard to fix, the question is when do we get something else out to you guys.

Will one of the female skippers please kiss this man! :D

ok, you asked for it...

http://www.subsim.com/radioroom/images/ranks/hangover.jpg

[nomad_delta]

I think it won't be hard to fix, the question is when do we get something else out to you guys.

Will one of the female skippers please kiss this man! :D

If one of them doesn't quick, I just might myself, and I'm not at all sure that'd turn out very well for anyone. :p

nomad_delta

[Reaves]

I think it won't be hard to fix, the question is when do we get something else out to you guys.


:huh:

:up:

[nomad_delta]

Yes, my testing so far seems to confirm it, which is very strange since I remember precisely testing it sometime in the past.

I think it won't be hard to fix, the question is when do we get something else out to you guys.

On a related note (and my lack of knowledge on historical sub torpedoes may be showing here), weren't the magnetic detonators designed (or at least intended) to be triggered only when the torpedo passed underneath the ship -- not out in front of it?

I'll do some more testing on that specifically when I get home (I've been waiting for a bus for the last 1.5 hours... grr!) but I seem to remember the magnetic torpedoes exploding way out in front of the ships rather than beneath them, even when I had prematures completely disabled in the .SIM file.

I wasn't looking for that specifically at the time, though, so I'll test again to be sure.

Is anyone here familiar with how the actual magnetic exploder mechanisms worked, or where I could find a technical drawing or schematic of one? I'm curious about the actual mechanics of how they were put together.

nomad_delta

[theluckyone17]

I think it won't be hard to fix, the question is when do we get something else out to you guys.
Will one of the female skippers please kiss this man! :D
If one of them doesn't quick, I just might myself, and I'm not at all sure that'd turn out very well for anyone. :p

nomad_deltaI'd be happy to buy 'em a beer or three... um, does anyone have any idea what overseas shipping is like on three cases of beer?

On second thought, maybe we ought to pull enough cash together to get the managers and bean counters drunk... drunk enough to approve a good sized team working on SH4?

[elanaiba]

If I remember correctly, the german magnetic triggers would detonate when the torpedo would pass underneath the ship - so it was only sensible to magnetic field detected above the torpedo.

BUT, that's not all. The torpedo would sense the magnetic field of the ship and only detonate when there would be a decrease in that field. Obviously, that would happen when the torpedo passed the keel of the ship and the curvature of the body (heh) would move the iron mass "away" from the torpedo.

So yes, it was all meant to have the torpedo go boom exactly under the keel, breaking the back of the ship.

This was also the intended behavior for our game ;) and more or less made it in.

[PepsiCan]

Yes, my testing so far seems to confirm it, which is very strange since I remember precisely testing it sometime in the past.

I think it won't be hard to fix, the question is when do we get something else out to you guys.

Assuming there will be a fix for the switch, can the premature explosions also include depth as a determinant for premature detonation? From what I have read, firing torpedoes running close to the surface will mean they will run eratic (circulars, running wide, prematuring).

And the best tip is to fire torpedoes from close range. I get few duds, but that's because I tend to attack from under 1200 yards.

And thanks for the patch! I've played it last night and it seems a more difficult and challenging experience.

[John Channing]

One of the main problems with the American detonators was that the inventors did not know enough about physics.

In Northern climates the magnetic field around a metal object tends to be roughly semi-circular in shape. The closer you get to the equator the flatter and shallower the field tends to be, to the point that, when you are at the equator, the field resembles a plate that stretches out from the object for a sizeable distance... thin, wide and shallow.

When a US torpedo would run into this flat, enlarged area it would set off he detonator at the edge of the field and you would get a premature explosion. If you set the torp to run deeper (or if it ran deeper than you meant it to which was the case through 42-43) it would run under the field and never detonate.

This is the reason the US Submarine Service finally had to give up on the magnetic detonators and go with contact only. It is also the reason why the German U-Boats, who operated in more Northerly climates, had more success... although they certainly has their problems too.

JCC

[tater]

I think it won't be hard to fix, the question is when do we get something else out to you guys.

Will one of the female skippers please kiss this man! :D

ok, you asked for it...

http://www.subsim.com/radioroom/images/ranks/hangover.jpg

That's gonna scare him away for sure... unless he likes that sort of thing (or has been at sea a looong tme). :D

tater

[Rockin Robbins]

Well, you have to say that elanaiba and crew are all over our concerns and have really hit a home run with patch 1.3! I can't say enough good about the way they fixed Silent Hunter IV, making it at least equal to SH3 and the best sub simulator the world has ever seen by a long way. I know Ubi is still taking heat over at the Ubisoft forums, but here where the real hardcore simmers hang out, we're happy. Patch 1.3 is an incredible job by a team that obviously cares about making their customers happy.

The premature explosions are actually a product of their dedication to ensuring that the game reflect reality in preference to being "fun" to play. That is a courageous decision and the correct decision. Mods are available that will "fix" it if desired. For the rest of us, we'll just set the switch to contact only as the real skippers did. Except we'll smile as we do it.

[nomad_delta]

The premature explosions are actually a product of their dedication to ensuring that the game reflect reality in preference to being "fun" to play. That is a courageous decision and the correct decision. Mods are available that will "fix" it if desired. For the rest of us, we'll just set the switch to contact only as the real skippers did. Except we'll smile as we do it.

Not to rain on the parade or anything, but you might want read this:

http://www.subsim.com/radioroom/showthread.php?t=118393

(To very quickly summarize, the Contact/Influence switch doesn't actually do anything)

I completely agree that 1.3 is an excellent patch and marks a massive improvement over 1.2. The devs really outdid themselves and I'm sure we all really appreciate their hard work.

That said, I don't want to shut down all discussion of things that could still use improvement just because SH4 is already really great and a lot of fun to play. Please don't take it the wrong way; by pointing out things that might not be working as we expect (or even the way the devs really intended for them to work) I'm not in any way trying to malign the excellent work they've already done.

I think the people here at SubSim (myself included to some extent) are much more likely to notice details that the 'average' gamer would miss entirely, since many of us tend to treat it less like a game and more like a 'reality simulator'.

I don't really think the devs or Ubisoft are under any real obligation to 'fix' or otherwise improve Silent Hunter 4 beyond making it playable and fun for the 'average' gamer, which they've already done quite well.

I really appreciate the fact that Elanaiba & crew are here at Subsim discussing these kinds of details with us, when they don't really have to be at all.

nomad_delta