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Under Water Warfare The Struggle Against the Submarine Menace 1939 -1945
Surface Ship weapons

Surface Ship weapons.

(a) Gunnery
The Gun remained an important weapon for the Surface Ship to combat a Submarine caught on the surface, or forced to surface as the result of a succesful under water attack. Anti-Aircraft armanent was a means of defending the ship when attacked by enemy Aircraft, any number of air attacks were aborted through spirited defence by the A.A. gunners.

(b) Asdic
This equipment fitted in Surface vessels for the detection of submerged Submarines, took its name from the initials of the "Allied Submarine Detection Investigation Committee," which produced the first primitive equipment towards the conclusion of W.W I. The basics consisted of a transmitter/receiver which sent and then picked up a returning echo which was audibly received through both ear phones and loud speakers.

The "PIING,"could be transmitted on a specitic bearing, thus one searched over a pre-determined arc, each side of the Escort's bows. The time interval between sending out this echo and its return, produced the range of the target which had been struck by the sound wave.

However, not only a Submarine will return an echo, eg. shoals of fish, a tide rip, whales, a wreck, or snapping shrimps, all will send back an echo. Only experience, and much exposure to hearing varying echoes will teach an Asdic Operator, an Officer of the Watch, a Captain, or an Escort Commander, the distinctive difference to a sound returned by a Submarine. Once one has heard the sound which emanates trom a Submarine, it leaves its very own "lasting impression."

This is the time the Asdic Operator, the Specialist Torpedo Anti-Submarine Oflicer, has trained for. The report is "Echo bearing Green 25," your Captain says "Classity" Your response, "Submarine Sir!" The ship alters course to Stem the contact bearing, and the attack commences. Now it's up to you to maintain contact, and not lose the wily enemy.

(c) Depth Charges
At the commencement of hostilities, the depth charge was the main Anti-Submarine weapon in Surface ships. It contained 290 pounds of Amatol within the total container, which weighed 400 pounds, and could be set to explode at varying depths from 50 to 500 feet. By the Spring of 1942, a special depth charge, to be carried by Aircraft had been developed. Its total weight was 250 pounds, having 165 pounds of explosive Amatol, and was designed to detonate at 25 feet below the surface of the ocean.

Depth charges were dropped astern of the attacking ship via rails, and throwers hurled them each side of the Port and Starboard Quarter, so that a pattern of charges would hopefully surround the U-Boat being attacked, and force it to the surface, to be dealt with by the Ship's Gunnery.

Depth Charge explodes astern of Escort

Depth Charge explodes astern of Escort

[ click for enlarged photograph ]

(d) Hedgehog
The use of depth charges had its attendant disadvantages. The Asdic dome was located in the keel usually below the bridge, thus, as the attacking vessel passed over the Submarine there was a dead time, the period elapsing from the last Asdic echo to the depth charge pattern being released from the stern. This is the period when the attacked U-Boat would choose to take evasive action.

Hedgehog Charge explodes

[ click for enlarged photograph ]

To overcome this problem, an ahead throwing weapon was designed, and "Hedgehog," came into being, so that the attacking vessel could still be in Asdic contact with the U-Boat or Submarine. In January of 1942, "Hedgehog," started to be fitted to Escorts. A salvo of 24 charges each weighing 32 pounds was fired ahead of the ship from a Spigot Mortar, the pattern formed an ellipse 120 by 140 feet, and it was hoped it would encompass the U-Boat, and destroy it. But unlike depth charges which exploded at the set depth, a direct hit had to be made with "Hedgehog," before it exploded. No explosion no kill.

To fit a Mortar mounting entailed giving up a foreward Gun Mounting, so the next move in the U-Boat hunting stakes, was the provision of an ahead throwing weapon that could be mounted on the Escort's stern, it was named "SQUID."

Hedgehog Charge explodes

[ click for enlarged photograph ]

(e) Squid
This was a much heavier version of an ahead throwing weapon than "Hedgehog," and comprised two Mortars, each with three barrels, each individual barrel throwing a 350 pound charge over a 700 yard distance, and ahead of the ship's bows. The "Squid," projectile could be pre set to explode at a set depth. and this weapon was too heavy to fit to the Flower class Corvettes, and was confined to Destroyers, Sloops, and Frigates

It made its first kill on the 31st of July, 1944, sinking U333

In my Torpedo Anti-Submarine Specialist capacity, I carried out the acceptance trials for the first "Squid" to be fitted in the R A N in one of Our "Tribal" class Destroyers, and vividly recall being showered with large pieces of Bakelite as they fell onto the bridge as the projectile hurtled over enroute to falling ahead of the ship, some one forgot to remove the protective covers prior to firing the "Squid."

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