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This trailer used to be part of a shore trainer in which crews sharpened their attacking skills and drills before going to sea for an operation. The complex of wheeled cabins used to contain sonar simulation of a variety of visual ship models that would be projected by camera into a periscope. Appropriate noises would accompany an attack - successful or otherwise! Such training has come a long way when you consider that the first anti-submarine warfare training used to be conducted during WWII in a London Bus!

The trailer has been converted into a gallery, and in it you can now see a magnificent collection of ship's badges as well as A history of Attacking underpinned by historic examples of 'fruit machines' and attack slide-rules.

For those who want a quick qualifying course in attacking, read on. For those who know how to do it already, go straight to submarine badges!

Quick Qualifying Attack Course

If you are still with me then imagine yourself in a wartime diesel submarine, armed with straight-running torpedoes, and think of the submarine as a barrel of a gun which has to be pointed in the direction of your target.

Before 'smart' weapons were introduced into his armoury, such as the wire-guided Tigerfish and Spearfish torpedo, and fire and forget weapons such as Sub-Harpoon anti-ship missile, a submarine captain had to be a great shot with his straight running torpedoes and had to be able to calculate the Director Angle (DA)(aim-off) before launching his torpedoes against his target. The DA was the resultant of 'the attack triangle'.

There are many ingredients that make up the attack 'cake'. First the attack triangle itself, which is added to the mix already in the bowl of target detection, identification, and the approach phase (which will have been conducted without alerting the target to your presence, particularly taking care not to let him see a 'feather' from your periscope when it is exposed).

There are three vectors involved in this triangle. (a) Target range, course and speed. (b) Own course and speed (c) Weapon course and speed. Your assessments of all three will determine the point in the ocean at which you want to arrive, the ideal firing position being 1000 yards on the target's beam. Be in this point a couple of minutes late, or a couple of hundred yards out of position, and you could stand little chance of success, and you may have wasted many hours of patient preparation. Add in the additional ingredients of target length and angle on the bow (i.e. its virtual length), its draught, prevailing sea-state and visibility, and torpedo reliability (which may not be 100%), and take account of any evasive manoeuvres (e.g. weaving) that the target may be using. Now add the spice of target detection capability against you, its escorts and accompanying aircraft, and their ability to counterattack. Mix in the final ingredients of remaining battery capacity (for evasion once you have created a 'flaming datum'), number of torpedoes remaining (or can you use your gun?), and your bone-weariness induced by many days at sea with little sleep. Now vigorously whisk the mixture before putting it in the oven. If you have got everything right, then your cake will have risen, and the cherry on top will be a successful engagement!

A straight running, impact torpedo was a pretty crude weapon, and because not many could be fitted into the torpedo stowage compartment, they could ill-afford to be wasted. So bit by bit, submarines got bigger to increase their weapon capacity, and more tubes were provided to enable a salvo to be fired to increase the likelihood of a hit. The purpose of the salvo was to provide a spread of weapons across the target's track so that any inaccuracy in the CO's estimations of target course, speed or range would be compensated for. For example a single torpedo fired against a target going two knots slower than estimated could result in it passing ahead. The effect of this misjudgement would be greatly exacerbated by assessing the target's angle on the bow incorrectly (i.e. target course), and further compounded by underestimating the target's range.

If (say) three torpedoes were discharged in a salvo then the first would be fired to hit a 10 knot target, the second to hit a 9 knotter (the estimate), and the third to hit the ship if it were travelling at 8 knots. Torpedo spread across the target's track would be achieved by applying a time interval between torpedo discharge or by observation of the target through the periscope with the CO applying his deflection angle against different parts of the ship (e.g. bow, middle, stern). Salvo size would be varied (provided you had sufficient weapons) depending on the importance of the target, and once again the CO had to apply fine judgement. The largest salvo in history was fired by Lieutenant (later Vice Admiral Sir) Arthur 'Baldy' Hezlet who, as commanding officer of HMS Trenchant during WWII, sank the Japanese battle-cruiser Oshigara which he hit with five torpedoes out a salvo of eight from a range of four thousand yards! Such was the strategic importance of the target, but with the submarine unable to close the range, this brilliant CO applied all the logic discussed above, and achieved his aim by covering all eventualities.

I think that I have demonstrated that much would have been going through the CO and his team's head in determining how and when to fire. Even the most outstanding mathematicians and instinctive attackers needed help, and this saw the invention of crude tactical aids in the form of slide rules. Before they became a patternised item they would be devised by the ship's officers and manufactured by the Engine Room staff from a variety of materials. Those on display date from WWI, and one of particular note was devised by an E-Class captain - I forgot to mention that this class of submarine also had a torpedo tube on either beam as well as forward and aft, so you can imagine the interesting calculation he had to make in determining which tube he could bring to bear the quickest, and what deflection angle he had to apply!

Another tactical aid that became popular in the 1930's was the ISWAS. This device was a relative velocity indicator which, once all the target and torpedo parameters had been applied, provided the necessary vector for ownship to follow to achieve the intercept of the target and achieve a successful attack.

After WWII life became more complicated for the Attack Team when Gyro angling and angular spread capabilities were introduced in to the MK VIII. These
parameters were passed to the electro-mechanical power setting units that plugged into the torpedo which were called GAPSUs and DPSU via the TCCS, (better known as the 'fruit machine'). The biggest advantage derived was that it was no longer necessary to point the submarine like the gun of a barrel, instead the Commanding Officer could fire over his shoulder if necessary, although it must be said that accuracy suffered at the extremities!. In addition he could shift target quickly, and alter the depth on his weapons if necessary. Needless to say 'gadgets' often broke down, so it was necessary for the post war CO to maintain all his basic attacking skills. Indeed during 'Perisher' (the Commanding Officers Qualifying Course), nothing would give 'Teacher' more pleasure than to 'break' the Fruit Machine at the last moment to force the student into breakdown fire. This used to happen regularly if the trainee was getting 'cocky' or being lazy in his approach to the target, and this despite the fact that he had successfully dodged his way past five escorts!

All the discussion hitherto has concerned attacking surface-ships, but what about the enemy submarine? The simple fact is that until the homing torpedo arrived on the scene in the 1950s unless you caught your target on the surface charging his battery or in transit, there were too many imponderables to solve to give your weapons much chance of success.

The first sinking of one submarine by another occurred in 1914 when the German U- spotted HMS C3 surfaced off the Dutch coast and blew her to bits. Although some members of the bridge party were seen afterwards in the water, there were no survivors.

The first sinking in history of a dived submarine by another did not occur until 1944 when Lieutenant Jimmy Launders in command of HMS Venturer (an improved Upholder Class) spotted the periscope of a U boat. Thereafter using a combination of visual sightings and ASDIC (sonar) information, Launders successfully assessed the target's course, speed and range and conducted his historic prosecution. He used a number of mental calculations that were to become familiar to all submariners, particularly the application of bearing rate techniques. In essence a target at 1000 yards doing ten knots at right angles to the line of sight (or sonar bearing) will induce a bearing rate of 10 degrees. Work out, or accurately assess, two out of the three characteristics, then the bearing rate will allow you to work out the third. Simple!

In HMS Alliance's Control Room, in addition to a TCCS 6 for the Mark VIII torpedo, you will see a TGCU 1(Torpedo Guidance Control Unit) for the Mk23 torpedo. The Mk23 was the Royal Navy's first wire guided, homing, torpedo. Driven by a battery, which meant that it was only half as fast as its diesel/shale oil engine powered predecessor, it was controlled by orders passed down a connecting wire to the vicinity of its target by the Command Team, and once close enough to detect the target's noise signature by a small sonar set in its nose, would home in and conduct its own attack. So for the first time it became possible to attack a submarine that was below periscope depth.

The successor to the Mk23 was the Mk24, better known as Tigerfish once it had been re-engineered by GEC-Marconi in the 1970s. The guidance control for this weapon is provided by DCB, and an example of the display can be seen in the SSN Control Room on the ground floor in the Mueum. This weapon is in service today, and many of its capabilities remain classified. However it is a wire guided active/passive homing weapon with both an anti-submarine and anti-surface ship capability. It has an impact and a magnetic fuse (look at the picture in the Weapons Gallery of what it can do to a frigate!) with a range in excess of 10 miles.

To match the full capability of the most capable of Soviet nuclear powered submarines during the Cold War, which were very fast and extremely deep-diving thereby posing a huge threat, GEC-Marconi developed the Spearfish torpedo. This is an awesome weapon which has an attack speed of 65 knots against its target, and can truly be described as 'smart' in that it has target recognition features, and can be used in a fire and forget mode should the tactical situation of the firing submarine require it.