Quote:
Originally Posted by Bubblehead1980
I remember watching a 5 part series via youtube a week or so ago about U boats, very good show.I remember one "Ace" was said to use one torpedo for one ship....were German torpedos the powerful?
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1943
Mark 14 torpedo (USN) 643 Pounds/292Kg of Torpex
G7a (German) 661 Pounds/300Kg Hexanite
Torpex consists of 42% RDX, 40% TNT and 18% Aluminum Powder
Hexanite or what the Germans called "SW39a" was 50% TNT, 10% Hexinit, 5% ammonium nitrate, and 35% aluminium powder.
Comparing explosives can be difficult. The term "more powerful" can be misleading. The term "Brisance" is used as a measure of how fast an explosive can reach its maximum pressure.
Explosives with lower Brisance well tend to push an object away (very low Brisance explosives can be used as a propellant). Explosives with a higher Brisance will tend to shatter an object.
Explosives with a lower Brisance will tend to have a longer explosive pulse (the duration of highest pressure). Explosives with a higher Brisance will tend to have a shorter explosive pulse.
So when trying to sink a ship with a torpedo, do you want explosives with a higher or a lower Brisance?
The answer is yes. Because torpedoes have the special advantage of being used underwater, the water can serve as what is called a Tamper. The inertia of water contains the explosive wave therefore increasing the duration (and incidentally focusing) the explosive pulse. What you want is an explosive that has both the effects of a higher Brisance (for the speed to get to maximum pressure) and the effects of a lower Brisance (for the longer duration of that maximum pressure). The trouble is that it is difficult to have both.......unless you are underwater.
The addition of Aluminum Powder to an explosive is an effective way to add the effect of a lower Brisance explosive to the existing higher Brisance.
As we learned in EOD school, a little pinch of powdered Aluminum is always a good thing.
Ok "professor" Platapus, you have used all the big impressive words, what the hell does all this mean?
Simply put, the ability to penetrate the hull of a ship is more affected by the higher Brisance of an explosive. But we don't need to penetrate the hull of a ship to sink it, all we need to do is separate the hull plates (think Titanic). This is more easily accomplished by using an explosive with a longer explosive pulse.
The Germans, in an attempt to economize, developed a combination explosive (Hexanite or SW39a) that while it had a lower total explosive power than Torpex (lower Brisance), the higher proportion of Aluminum powder turned that lower power explosive compound into a more effective explosive compound. Effective for this one purpose, that is.
This is why it is difficult to compare explosives. It depends on the compound and its intended use. This is why we don't just put C-4 in to every piece of ordnance. C-4 is good at what it does, but other explosive compounds are good at what they do. There is no universal "best" explosive.
So to reference back to the original question, yes the German torpedoes using SW39a were more effective at comprimising the integrity of the hull plates of merchant ships, despite being "less powerful" than US torpedoes using Torpex.
If your intended target is an armoured hull of a military ship, the story changes. To penetrate armour (as opposed to spalding the armour) you will need a higher Brisance explosive.
In this case, the US torpedoes with Torpex woudl be more effective at compromising the integrity of the armoured hull of a military ship..... assuming the damned Mark 14/Mark 6 even functioned.. but that is another story.
Probably more than you wanted to know. But when discussing the effectiveness of explosives, some background needs to be understood.
And we did not even touch on the secondary explosive effects or the depth of the explosive pulse.
