Author Topic: 540 Coast Regiment  (Read 8475 times)

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Offline John

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Re: 540 Coast Regiment
« Reply #15 on: February 22, 2012, 10:00:35 am »
ii.  Communications.

The Fire Command was originally installed with the standard pre-war communications considered essential for a counter-bombardment layout. Some mention of the alterations that were required to deal with the changing circumstances has already been made, but it will be advantageous to list all the alterations that were eventually made.

As soon as it had been decided that the Battery Commander's place in action should be the B.P.R., the following alterations to the existing communications were authorised.

(i) Telephones from the F.C. Post via Command Exchange to BOPs were withdrawn, except in the case of the 6-inch Battery which had a close defence role in addition, and were replaced by direct lines from the F.C. Post to B.P.R's.

(ii) The two lines from the Rangefinding Exchange to B.O.P's (one for Fortress telephonist, and the other for telephonist to aircraft) were removed, and similar lines installed in the B.P.R. except that it had now been found better to communicate with aircraft with VHF R/T equipment, which was therefore installed in the B.P.R, instead of the second R/F line.

(iii) A two-way loudspeaking Tannoy system was installed between F.C. Post and each B.P.R., which could also be worked on a multiple system, so that Fire Commander and Battery Commanders were able to communicate with each other direct.

(iv) Direct lines from F.C. Post to each Radar Set, and the multiple telephone connecting all Radar Nos 1 have already been mentioned.

These new telephone lines had the additional advantage of making the whole system more flexible, and gave certain very essential alternative communications which did not exist before. As was found in Dover, the communications are the most vulnerable portion of the whole layout, and alternative lines were found to be essential. Even with these lines, a time did come when for a few minutes in action the only communication between the F.C. Post and the 9.2-inch Battery was by means of a No. 17 R/T Set:
"You know, if you don’t read history, you’re a bloody idiot." - James Clavell

Offline John

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Re: 540 Coast Regiment
« Reply #16 on: February 23, 2012, 09:05:43 am »
iii. Observation of Fall of Shot.

Two methods of obtaining fall of shot observations were tried :-

i. From Radar Sets.

ii. From Aircraft (c.A. Co-operation Unit).

The second method can be disposed of in a few words. The method of communication was by VHF equipment, and during practices observations from the Air O.P. pilot in the form of clock-code reports were on the whole very satisfactory. Unfortunately permission to fly by night was very difficult to obtain at the time, and on the one occasion when the pilot went up at night his aircraft developed engine trouble before locating the target, and on its way back to base, crashed. No further night flights during operations were tried although a number of experimental flights with different types of aircraft, (Spitfires, Beaufighters etc) showed that night spotting by aircraft had great possibilities.

On 17 Sep 44, when supporting the Canadians by bombardment at shore targets in daylight, an Air O.P. pilot was the only source of information with regard to fall of shot, and was highly successful.

Observations from Radar Sets improved steadily as the performance of the Set as a Rangefinder advanced. In early actions the only sets available for fall of shot were one "K" (K.147) and one "M" (M.2) and an N.T. 284 which was normally being used as a rangefinder at the same time. The first addition to this was when an experimental "B" set (B(p)X) was installed at M.2 in the place of the "M" set which had been of little or no use for fall of shot.
"You know, if you don’t read history, you’re a bloody idiot." - James Clavell

Offline John

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Re: 540 Coast Regiment
« Reply #17 on: February 24, 2012, 09:11:38 am »
The main trouble with all these sets was the size of the target echo. At the very minimum this had to be taken as 40' in breadth and from 50 yards minus of the target to 250 yards plus, and any shot falling in this area was almost impossible to identify for certain, and if seen, could only be reported as "target area".

The first improvement came when an "L. 17" panel was fitted to the UF" set in the F.C. Post, and the target echo box for range was somewhat reduced. However no improvement was found with regard to bearing, and all sets had great difficulty  reporting more than tendencies Left and Right. In addition, due to the narrowness of the beam transmitted, salvoes more than one degree out for line were seldom picked up at all.

Many methods were tried to overcome this very great failing, the most important of them being :-

1. If three Radar Sets were available for Fall of Shot, the best (normally the "F" set with the L.17 panel) laid on the target itself, while the others were ordered to follow, one a degree in front, and the other one degree behind the target. It Was then found that salvoes reported "0.U" on the main set, were often located by one or other of the flanking sets and a line correction could be given.

2. As it was easier to observe rounds falling short, every now and again a confirmatory salvo would be fired with a large minus correction on it, if a series of  "0.U" or "T.A" (target area) observations had been received. For example:-

Salvo 1. Minus 200    Order Add 200
        2. T.A.         "        -
        3. O.U.         "        -
        4. T.A.         "   Drop 1,000
        5. Minus 900    "   Add 900.
"You know, if you don’t read history, you’re a bloody idiot." - James Clavell

Offline John

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Re: 540 Coast Regiment
« Reply #18 on: February 25, 2012, 08:23:38 am »
3. If a series of salvoes were reported as "0.U" and there was still doubt as to whether the line had been correctly established, subsequent salvoes were fired with successive small corrections for line, normally of 30' each cormnencing in the direction of movement of the target. For example :-

Salvo 1. O.U.
        2. O.U. Order R 30' (target moving left to right).
        3. O.U. Order R 30'
        4. O.U. Order R 30'
        5. O.U. Order L 20
        6. O.U. Order L 30'
        7. Right
        -300 Order L 20' Add 300
        8. K.K.


4. As some sets available for fall of shot were sometimes considerably to a flank at one time the encoding of these reports was tried, but the method was not found to be satisfactory and was dropped.

One golden rule was soon learnt. A "B" Set could not give satisfactoey results as a rangefinder, and at the same time observe fall of shot at long range. Each job at ranges over 30,000 yards was very skilled, and required different settings on the controls. And so it had to be made a rule that when other sets were available, the rangefinding set would not look for fall of shot.

In these early stages fall of shot was a very great problem, and it was a full time job to sort out various reports which were received from sets and obtain a true picture of the M.P.I. of any one salvo. To meet the special circumstances a departure from normal practice was tried, and all fall of shot reports were sent to the F.C. Post, where an officer spent his whole time sorting them out, and deciding on an M.P.I. to be passed to the Battery Commander.
"You know, if you don’t read history, you’re a bloody idiot." - James Clavell

Offline John

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Re: 540 Coast Regiment
« Reply #19 on: February 26, 2012, 14:52:01 pm »
This system had certain disadvantages, chiefly with regard to the additional time it took to get the fall of shot report to the Battery Commander. Nevertheless in spite of this, the system paid handsomely, and the final result was obviously much better than the B.C. would have obtained from his own Battery Set, especially if this had been supplying him with rangefinding information as well.

Most of the difficulties mentioned above were largely eliminated, on the arrival of "CHARLIE" the name given for security reasons for the prototype of the C.A. No. 1 Mk IV which has already been mentioned. This set was designed to act as a rangefinding set and a fall of shot set at the same time, and a separate tube is incorporated for the fall of shot presentation. This tube is graduated both for line and range, so that an M.P.I. can be read straight off the tube, and provided the salvo falls within 3 degrees and 1,000 yards of the target in any direction, there is no reason at all why the fall of shot should not be seen. In addition a separate operator can be observing on the remote tube, so that confirmation is always obtainable. In future when all Batteries are equappedwith this type of set, the troubles experienced with obtaining accurate fall of shot will be almost entirely eliminated.
"You know, if you don’t read history, you’re a bloody idiot." - James Clavell

Offline John

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Re: 540 Coast Regiment
« Reply #20 on: February 27, 2012, 10:07:08 am »
iv. Enemy tactics.

So far difficulties that arise due to the imperfection of equipment have been dealt with, but now it is necessary to consider how the tactics of the enemy will upset even the most perfect equipment.

Throughout the early months of 1942, little if any avoiding action was taken by enemy vessels moving between Calais and Boulogne. The main idea appeared to be to take the shortest route at something that approximated to the fastest speed. Later, however, strong avoiding action was taken, and as fast as counter-action was taken by the guns, SO a new move was tried by the enemy. This was so apparent that it is probable that convoys were taken through the Straits by the same pilots, time after time, who began to learn how the gunner would react to any particular move.

Avoiding action was taken in one of three main forms :-

(a) Disturbance of Radar information by escorting vessels.

If the smaller escorts of a large vessel continually circle round the vessel, the operator on the Radar Set (especially "B" type) has the greatest difficulty in remaining on the same target. Alternatively a Fall of Shot set may give its reports with relation to another target.

The method of combatting this move by the enemy with the older types of Radar Sets has already been mentioned. As all Nos 1 are linked on the same telephone and are encouraged to voice their difficulties, and to compare their bearings and ranges, any sudden alteration will be noticed by one of the Nos 1 who will be able to warn the others, and special care will be taken not to change target.

(b) Violent alterations in course and/or speed.

If these alterations take place between "shot" and "splash" time, it will mean that travel corrections added into the salvo at "shot" are completely stale by "splash".
"You know, if you don’t read history, you’re a bloody idiot." - James Clavell

Offline John

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Re: 540 Coast Regiment
« Reply #21 on: February 28, 2012, 08:55:44 am »
There is no scientific way of counteracting this move, which can have considerable effect when times of flight of as much as 90 sees are involved. It may be able to be overcome by the B.C. anticipating the next move of the helmsman, but this is leaving too much to luck, and the method tried to lessen the effect was to make it more difficult for the helmsman to decide when to turn.

To bring this plan into effect, the assistance of the smaller calibre batteries was sought.  At 35,000 yards the flash produced by any gun of over 6-inch calibre looks approximately the same. And so, all the guns available in the Fire Command were divided into pairs, and by controlling the fire of these pairs from the F.C. Post, it was possible to arrange it that a pair of guns fired every 20 seconds. The following were used 2 x 15-inch, 2 pairs of 9.2-inch, 2 pairs of 5.5-inch and 2 x 6-inch. Whenever the guns able to fire the required range were ready to fire, they were ordered to fire at the next 20-sec interval, and the gaps were filled by the guns of smaller calibre producing a flash.

This method was found to be very effective, and the ill-effects of a constantly turning target were somewhat reduced, as it was impossible for it to start a new turn every time the 15-inch or 9.2-inch guns fired, and therefore the Battery Commander had a sporting chance of deciding what the target would do during the next 90 seconds. It was greatly assisted by the introduction of an automatic Plotter in the 15-inch B.P.R., which gave the Battery Commander a very up-to-date picture of what the target was doing.

One final point in procedure should be mentioned before closing. A method of witness-point shooting was tried towards the middle of 1944 which had very definite possibilities. Prior to the engagement of a target, the Radar Set was laid at a fixed point, and the bearing and range transmitted to the guns. One salvo was fired, and the guns were then "datumed" on that point, any spotting correction that was required to make them fall on the exact spot being added. This eliminated the chances of large errors on the first salvo, due to inaccuracies in the
"You know, if you don’t read history, you’re a bloody idiot." - James Clavell

Offline John

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Re: 540 Coast Regiment
« Reply #22 on: February 29, 2012, 08:12:11 am »
meteor telegram, or in the assessment of muzzle velocity. Provided the spot chosen could be on approximately the same bearing and at the same range as the opening salvo, that opening salvo should be a lot more accurate than normal.

This method was tried with great success when firing at shore installations, when Radar fall of shot reports were impossible, and when it was necessary to rely entirely upon the air O.P. Both the Royal Marines and the 15-inch Battery fired a salvo at the same bearing and range as the wreck of the "MUNSTERLAND", guns were corrected to this location, and then "lifted" to the shore target indicated. As a result the opening salvo was always close to the target, and gave the Air O.P. pilot a chance of sending an accurate fall of shot report.

The above account gives some indication of the difficulties that were actually encountered by the Dover Batteries in their engagements. It has always been pointed out that the use of the C.A. No. 1 Mk IV Radar Set has eliminated a number of those difficulties, and as Radar and Fire Control Instruments are still further improved, more and more of those difficulties will disappear. What appeared at first to be the almost impossible task of engaging a fast moving target at a distance of over 20 miles has already been made a practical possibility, and will soon be rewarded with almost certain success. The one problem that cannot be solved mechanically is anticipating what an enemy ship will do after a shell has been fired, and before it arrives at the end of its journey. However, even the difficulty occasioned by this will be much reduced if the number of guns at the disposal of the Fire Commander is substantially increased.
"You know, if you don’t read history, you’re a bloody idiot." - James Clavell

Offline John

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Re: 540 Coast Regiment
« Reply #23 on: February 29, 2012, 08:17:36 am »
Here's the final page of the 'Short Story Of The Guns At Dover Engaged With The Enemy'..
"You know, if you don’t read history, you’re a bloody idiot." - James Clavell

Offline John

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Re: 540 Coast Regiment
« Reply #24 on: March 01, 2012, 11:19:59 am »
A photograph sent to me by former 540 Coast Defence Regiment officer Lionel Strange. The picture was taken in 1943 in the garden of South Foreland Lighthouse, and Lionel has provided the names as follows:

Back row, left to right. Unknown, Unknown, Major W.Eaton (OC Fan Bay Battery), Unknown, Captain A.L. Strange (took over Fan Bay in August 1944), Unknown, Unknown, Lieutenant Philpots (Armament Officer).

Front row, left to right. Unknown, Major E.D. Hagger, Unknown, Lieutenant Colonel J.H.W.G. Richards, Major E.B. Edmonds, Major R.F.A. Mallinson, Captain A. Boardman.
"You know, if you don’t read history, you’re a bloody idiot." - James Clavell

Offline John

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Re: 540 Coast Regiment
« Reply #25 on: March 03, 2012, 18:13:21 pm »
Soldiers in the Fire Command Post of 540 Coast Defence Regiment. No names for any of these men unfortunately.
"You know, if you don’t read history, you’re a bloody idiot." - James Clavell

Offline John

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Re: 540 Coast Regiment
« Reply #26 on: May 17, 2012, 07:55:17 am »
War Diary for 540 Coast Regiment, September - December 1941.
"You know, if you don’t read history, you’re a bloody idiot." - James Clavell

Offline John

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Re: 540 Coast Regiment
« Reply #27 on: May 17, 2012, 07:56:07 am »
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"You know, if you don’t read history, you’re a bloody idiot." - James Clavell

Offline John

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Re: 540 Coast Regiment
« Reply #28 on: May 17, 2012, 07:56:50 am »
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"You know, if you don’t read history, you’re a bloody idiot." - James Clavell

Offline John

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Re: 540 Coast Regiment
« Reply #29 on: September 25, 2012, 16:41:11 pm »
Officers and men of 540 Coast Regiment in 1944, possibly at South Foreland 9.2" Battery.
"You know, if you don’t read history, you’re a bloody idiot." - James Clavell