Magnetic torpedo question

[kapuhy]

Let's say I am directly behind 150 meters long enemy ship in a convoy in a really bad weather - visibility is about 200 meters, so I have no chance to aim a shot properly. But if I fire a magnetic torpedo up his back from those 200 meters, theoretically it should arm itself and explode while still being under the target. Will this work or the torpedo has to be already armed while entering magnetic field of the target ship?

[Gargamel]

In real bad weather, mag eels have a chance of detonating prematurely. They also risk missing the boat completely as the heaving of the seas may lift the boat higher, and the eel pass right under. With a pure stern shot, that's a reduced risk, but the chances of a hit are still low. If you run it shallow, you may hit the rudder or screws and it will probably die or bounce off. You're better off looking for a better shot, or waiting for him to zig zag so you can shoot from the side.

But let's say you manage to side one up the slide of the ship, it should arm while along side, and then it should detonate.

[CCIP]

It might work, you have a chance. Not a very good one, but yes, even ignoring the premature tendency, you have to keep in mind that the waves will mess things up. While torpedoes in SHIII will go straight and level regardless of weather (not as in real life, where they would obviously go up and down with the waves), the ships will definitely go up and down and drafts of individual sections of the ships will change. This can be a problem because your torpedo might either pass under, or more likely, bump into the ship as it's passing under it, before getting armed.

To make this simpler - it's definitely possible, but depending on the target it might not be worth the risk. I'd give it a very low chance of working, and a very high chance of not exploding, hitting the ship before arming and going dud, or otherwise not functioning. Given the impromptu targeting there, I'd give this a 10% chance of success at best. Is that worth a precious torpedo that could sink a whole ship under good conditions? Up to you...

[kapuhy]

Thanks for replies! I was asking because of what happened on my last patrol. I've wandered into a convoy in foulest weather I've ever seen. I damaged a freighter with a "snapshot" from the stern launcher after almost colliding with it and as a result the convoy formation turned into chaos - I was going blind on the surface, with searchlights from destroyers blinking through the rain and freighters going in random directions, appearing suddenly next to me.

I was unable to get a good aim at anything, so I was about to try the tactic I've described above, but didn't get the chance - as I was trying to get into position, a destroyer appeared and started shelling me, so I had to crash dive. I was simply curious if it had a chance to work at all.

[desirableroasted]

Originally Posted by kapuhy

Let's say I am directly behind 150 meters long enemy ship in a convoy in a really bad weather - visibility is about 200 meters, so I have no chance to aim a shot properly. But if I fire a magnetic torpedo up his back from those 200 meters, theoretically it should arm itself and explode while still being under the target. Will this work or the torpedo has to be already armed while entering magnetic field of the target ship?

At that range, it will not arm, and it must be armed before it can explode.

Also, directly behind (000) is a tough shot, though once you get 10 degrees out either way, you should be fine.

At short range (300-500 m), even in rough weather, premature detonation is not a big problem, no matter what the manuals say. Maybe 5% will go off early.

But attacking convoys in really rough weather is not advisable. As you point out, well-considered shots are impossible. Worse, if you do hit something, you will find it very hard to find again. Even worse, you can be sliced in half by another merchant as you try to line up your shot.

On my boat, in rough seas, we go down below and pinch each other.

[kapuhy]

Originally Posted by desirableroasted

At that range, it will not arm, and it must be armed before it can explode.

The idea was for it to arm while being under enemy ship (200 meters range to target's stern and then the entire length of a ship before torpedo leaves magnetic field, so with big ships it should hit 300 meters mark while still inside the field).

Originally Posted by desirableroasted

But attacking convoys in really rough weather is not advisable.

After spending 2 weeks in a raging storm and watching convoys go by I became kind of desperate.

[Sailor Steve]

Originally Posted by kapuhy

The idea was for it to arm while being under enemy ship (200 meters range to target's stern and then the entire length of a ship before torpedo leaves magnetic field, so with big ships it should hit 300 meters mark while still inside the field).

That is true of impact shots as well. Two hundred yards is a bit close, but if it's a trailing shot there's a chance that it will work. As long as the torpedo travels the required 300 yards before getting to the target it will arm.

After spending 2 weeks in a raging storm and watching convoys go by I became kind of desperate.

I know the feeling. I just played an August '39 start in SH3, and after two months at sea I returned home with exactly one kill. I'm currently in an early war mission with SH4 and OM, and it's starting to look like the same thing. Patience, my son.

[desirableroasted]

Originally Posted by kapuhy

The idea was for it to arm while being under enemy ship (200 meters range to target's stern and then the entire length of a ship before torpedo leaves magnetic field, so with big ships it should hit 300 meters mark while still inside the field).



After spending 2 weeks in a raging storm and watching convoys go by I became kind of desperate.

Got you. Many miss the 300m thing.

Watch them go by.. nothing to be done about it.. Trail them as best you can until weather improves.

Unless you are using the "lock cheat," you can't shoot them within arming range, and, even if you could hit them, you can't find the cripples in the murk.

No shame in walking away from a convoy in bad weather.

[bookworm_020]

If you set the torp to run 1.5 to 1.8 meters below the kheel on mag settings and fire your torpedo at no less than 220 meters for a stern shot (with no more than 30 degress off the stern) you have a good chance of a hit in rough weather.

If the taget is coming toward you, 300 meters is the min range to shoot at if your have any chance of a hit.

If your fireing from the beam (90 degrees from the target) aim for the center of the ship as it will have less vertical movement than the bow or the stern.

[desirableroasted]

Originally Posted by bookworm_020

If you set the torp to run 1.5 to 1.8 meters below the kheel on mag settings and fire your torpedo at no less than 220 meters for a stern shot (with no more than 30 degress off the stern) you have a good chance of a hit in rough weather.

If the taget is coming toward you, 300 meters is the min range to shoot at if your have any chance of a hit.

Sorry, comrade, but your advice is rubbish.

He has to consider four variables: 1) his angle on the target, 2) target speed, 3) torpedo speed and 4) torpedo arming range. All affect the mathematical calculation to determine when to fire.

For example, HMS Hood coming straight at him is making 25 knts, or 12.88 meters a second.

A T1 fired at high speed will make 44 knts, or 22.6 m/s. Thus, the T1 needs 13.27 seconds to arm (300 m).

To be armed under his target point under Hood, however, he must consider how far Hood travels in 13.27 seconds -- and that is 171 meters.

A shot of anything less than 471 meters -- 500, really, given lags, itchy fingers -- is going to fail (or not explode where he wants).

Do the freaking math! Obviously, if your torp needs 300 meters to arm, it will not explode under your 300 meter target point if the target is moving toward you .

You can do the math yourself and realize that your 220m from behind rule is equally specious. From directly behind Hood, you could shoot at 150 and be right on the dime.

Now, change out Hood for a slow freighter. And set your T1 to "slow". All the numbers are different.

So let's not toss out "rules of thumb" like "no less than 220 meters from the stern" and "300 meters from the front" without doing a little work with the calculator.

[desirableroasted]

Originally Posted by bookworm_020

If your fireing from the beam (90 degrees from the target) aim for the center of the ship as it will have less vertical movement than the bow or the stern.

Moreover, it has been discussed here many times: impact shots in rough weather should go to the bows, ideally between compartments (the target line generally being under the first crane).

I think this is pretty much doctrine.