Torpedos exploding on CMs

[MBot]

I found some interesting info on this page:

http://milit.ru/torpedoes.htm

Of interest are these expressions:
"passive acoustic noncontact exploder"
"radically new optical exploder"
"active acoustic noncontact exploder"

I know that there is not realy any techical explanation, but the page seems to be written by trustworthy people.

The question now is, how would such fuses react on CMs? Is the stance that torpedos do not detonate on CMs still applicable, or would at least some detonate on CMs because any of the above fuses gets triggered?

Also, what kind of fuses do US torpedos use? Only magnetic and contact? If so, would contact fuses be the only detonators against titanium subs like the Alfas or Sierras?

[LoBlo]

This is really interesting. It doesn't sound a an extremely radical idea, so I'm sure that most of the worlds subforces probably have at least entertained the idea. Question is, how "close" does a torp get to its CM, and how large is the shock wave from the explosion.

Anyone got any data from the old WWII depth charges? Maybe that would give a clue about how close a torp would have to get to be effected by a CM explosion...

[AirHippo]

Off the top of my head, and with a bit of reference to George Franklin's excellent Britain's Anti-Submarine Capacility, 1919-1939, it would seem that the supposed "area of probably serious damage" for a single depth charge, in the Royal Navy, was forty yards. Given that the charges in question were 300-lb Amatol weapons, that seems likely rather more than any countermeasure designed to trigger a torpedo by concussion would be able to generate; even accounting for improvements in explosives, one imagines that a countermeasure should, ideally, be easy to reload.

[MBot]

Oh I think you might have misunderstood me. What I meant is that a torpedo explodes when passing a CM, thinking that it is the target sub (because the torpedos active or passive acoustic fuze gets triggered).

Altough your idea is not far off. As far as I know, the smaller russian ASW mortars like RBU-1000 (rocket propelled depth charges) installed on surface warships, are primary meant as last defence against torpedos. Just like CIWS.

[Castout]

Originally Posted by MBot

...........

Of interest are these expressions:
"passive acoustic noncontact exploder"
"radically new optical exploder"
"active acoustic noncontact exploder"

They are torpedoes fuses.

what do they have to to with torpedoes exploding on countermeasures?
I don't think torpedoes would explode on countermeasures.

That's why the US have the nixie towed torpedo countermeasure because conventional CMs do not detonate torpedoes.
The nixie I believe would in most probability detonate incoming torpedo.

It would be stupid to tow a torpedo countermeasure if conventional CMs would detonate enemy torpedoes.

[MBot]

Why could a torpedo with a active acoustic fuze not detonate on a CM that generates a active sonar return. Or why could a torpedo with a passive acoustic fuze not detonate on a CM that creates a passive sonar signature?

[Castout]

Originally Posted by MBot

Why could a torpedo with a active acoustic fuze not detonate on a CM that generates a active sonar return. Or why could a torpedo with a passive acoustic fuze not detonate on a CM that creates a passive sonar signature?

I do not know for sure why but I could guess.

I believe active or passive homing are merely homing guidance type of the current modern torpedoes. besides of course the wake homing torpedoes.

So you have active-homing torpedoes, passive-homing torpedoes and wake-homing torpedoes. These are merely the type of guidance of the torpedoes.

The torpedo exploders on torpedoes are entirely another thing(another equipment on the warhead). But this is just my guessing.

Another possible reason is that conventional countermeasures are not strong enough to trigger the fuses if the fuses are indeed based on its guidance type. For example the active return from an active countermeasures are never strong and rapid enough to trigger the fuses on the torpedo warhead simply because the countermeasures are too small to mimic genuine terminal return of a real homing torpedo.

Aside from those two possibilities why would the US Navy employ towing of torpedo decoy abroad their surface warship if countermeasures do detonate incoming torpedoes?

Here's a little quote from the link you provided in your first post:

In 1950, the first Soviet homing torpedo outfitted with a passive seeker and electromagnetic exploder, SAET-50, became operational.

the MGT-1 400mm homing torpedo with passive seeker was made to protect submarines against surface ships. Its passive acoustic noncontact exploder detonated the charge near the ship propeller.
This merely means that the guidance system of the torpedo will bring the torpedo to the source of noise which is the propeller but the exploder is a noncontact type of unspecified mechanism.

In 1956 the 53-56 antiship aimed gyrating oxygen torpedo, provided with a radically new optical exploder was designed.
I think the exploder is using a HF sonar mechanism which is called optical exploder. But this is just my guess. The 53-56 guidance system is not specified though though it is stated that the torpedo role is anti shipping. Perhaps it was the progenitor of the wake homing 53-65 K torpedo? Or perhaps it was intended for anti ship because of its limited range and or its limited speed.

[LoBlo]

Originally Posted by MBot

Oh I think you might have misunderstood me. What I meant is that a torpedo explodes when passing a CM, thinking that it is the target sub (because the torpedos active or passive acoustic fuze gets triggered).

Oh...

Well, it *and* even the misunderstood question are pretty interesting.

I think that these fuses are likely trying to achieve an "underhull" detonation (as opposed to a contact detonation) for more destruction power. I don't know what the actual fuze on a Mk48 sonar is... its probably classified