PDA

View Full Version : Maybe a bright spot in the MK-14 saga...



Crosseye76
03-16-2007, 10:39 PM
I found this at the superb Torpedoes link:


"Warheads

The second major development, new warheads, involved the switch from TNT to Torpex as the high explosive. Torpex is a mixture rather than a pure chemical compound as TNT is. The components are TNT 41%, RDX (Cyclonite, Hexogen) 41% and aluminum powder 18% (8). Torpex is attractive because of the increased explosive energy and higher detonation velocity of RDX as compared to TNT and the prolongation of the pressure wave by the aluminum. On a weight basis, Torpex is conservatively about 50% more effective than TNT as an underwater explosive against ships. Torpex is, however, more sensitive than TNT and RDX was expensive and difficult to make safely. The process of converting to Torpex torpedo warheads (and depth charge loadings) began with an order for 20 million pounds in early 1942 (9). The first Torpex loaded warheads (10) followed late the same year. The 640 pounds of Torpex in a Mk.14 warhead was at least the equivalent of 960 pounds of TNT (11) almost twice the destructive power of the original Mk.14.

The reaction of the submariners to Torpex is apparent from an entry for 19 March 1943 in the fourth war patrol report of USS Wahoo:

"0515H; Fired one torpex torpedo at medium sized freighter identified as KANKA MARU, 4,065 tons, range 750 yards, 120 port track, speed 9 knots. Hit. After part of ship disintegrated and the forward part sank in two minutes, and 26 seconds. These Torpex heads carry a [sic] awful wallop."

This very substantial improvement in warheads is often overlooked in part because the torpedo identification does not automatically identify the warhead and even the warhead Mark doesn't unequivocally identify the high explosive. Some Mk.14-3A torpedoes were fitted with TNT warheads, most commonly Mk.15, and others with Torpex warheads, most commonly Mk.16. Furthermore torpedo warheads could be easily changed by a tender or depot. The standard ComSubPac format for war patrol reports did not require listing torpedo or warhead Marks and Mods. until after April 1943.

____________________



8 Torpex ranges from 45% TNT, 37% RDX, 18% Al to 41% TNT, 41% RDX, 18% Al

9 Interestingly, the US Army was willing to produce cyclonite, RDX, for the Navy's use in Torpex, but was reluctant to use it for Army munitions because of safety concerns.

10 Torpex and TNT warheads were interchangeable. If there was a substantial change in weight, some adjustment to the depth gear was required.

11 Comparisons with Japanese torpedoes often neglect the difference in high explosives. Japanese torpedoes used Type 97 high explosive, which is not significantly more powerful as an underwater explosive than TNT."


I hope this is reflected in the game. It will be some good torpedo news for a change !



Find the full text at:

U.S. Navy Torpedoes (http://www.geocities.com/Pentagon/1592/torpedos.html)

Crosseye76
03-16-2007, 10:39 PM
I found this at the superb Torpedoes link:


"Warheads

The second major development, new warheads, involved the switch from TNT to Torpex as the high explosive. Torpex is a mixture rather than a pure chemical compound as TNT is. The components are TNT 41%, RDX (Cyclonite, Hexogen) 41% and aluminum powder 18% (8). Torpex is attractive because of the increased explosive energy and higher detonation velocity of RDX as compared to TNT and the prolongation of the pressure wave by the aluminum. On a weight basis, Torpex is conservatively about 50% more effective than TNT as an underwater explosive against ships. Torpex is, however, more sensitive than TNT and RDX was expensive and difficult to make safely. The process of converting to Torpex torpedo warheads (and depth charge loadings) began with an order for 20 million pounds in early 1942 (9). The first Torpex loaded warheads (10) followed late the same year. The 640 pounds of Torpex in a Mk.14 warhead was at least the equivalent of 960 pounds of TNT (11) almost twice the destructive power of the original Mk.14.

The reaction of the submariners to Torpex is apparent from an entry for 19 March 1943 in the fourth war patrol report of USS Wahoo:

"0515H; Fired one torpex torpedo at medium sized freighter identified as KANKA MARU, 4,065 tons, range 750 yards, 120 port track, speed 9 knots. Hit. After part of ship disintegrated and the forward part sank in two minutes, and 26 seconds. These Torpex heads carry a [sic] awful wallop."

This very substantial improvement in warheads is often overlooked in part because the torpedo identification does not automatically identify the warhead and even the warhead Mark doesn't unequivocally identify the high explosive. Some Mk.14-3A torpedoes were fitted with TNT warheads, most commonly Mk.15, and others with Torpex warheads, most commonly Mk.16. Furthermore torpedo warheads could be easily changed by a tender or depot. The standard ComSubPac format for war patrol reports did not require listing torpedo or warhead Marks and Mods. until after April 1943.

____________________



8 Torpex ranges from 45% TNT, 37% RDX, 18% Al to 41% TNT, 41% RDX, 18% Al

9 Interestingly, the US Army was willing to produce cyclonite, RDX, for the Navy's use in Torpex, but was reluctant to use it for Army munitions because of safety concerns.

10 Torpex and TNT warheads were interchangeable. If there was a substantial change in weight, some adjustment to the depth gear was required.

11 Comparisons with Japanese torpedoes often neglect the difference in high explosives. Japanese torpedoes used Type 97 high explosive, which is not significantly more powerful as an underwater explosive than TNT."


I hope this is reflected in the game. It will be some good torpedo news for a change !



Find the full text at:

U.S. Navy Torpedoes (http://www.geocities.com/Pentagon/1592/torpedos.html)

RedTerex
03-16-2007, 10:54 PM
I believe that Torpex (Torpedo Explosive) was also used in the 'Grand Slam' bombs as dropped by the RAF Lancaster bombers, in particular to sink the German Battleship Tirpitz. 2 Direct hits actually made the ship capzize in shallow waters.

She was cut up after the war for scrap steel.

The power of Torpex went on to be developed I understand into todays equivalent called Semtex, and the explosive force was made more severe by using it in the 'Shaped Charge' configuration.

Realjambo
03-17-2007, 03:16 AM
Good post Crosseye 76 http://forums.ubi.com/images/smilies/25.gif

'Tall Boy' bomb as dropped on the Tirpitz - judging by the scale of the two handlers in the photo, I'd guess a Tall Boy was about 13 feet long?
http://img.photobucket.com/albums/v642/antsmith/p_tirpitz3tallboy.jpg

Tirpitz capsized after the attack, ready to be scrapped
http://img.photobucket.com/albums/v642/antsmith/p_tirpitz8-1.jpg

RedTerex
03-17-2007, 07:20 AM
Thanks for the supporting photos RJ !

Yes there were two such bombs 'tall-boy' and 'grand slam', both developed by Sir Barnes Wallis, the boffin who invented the bouncing bomb too.