Additional Report of B.C.F. Gunnery Committee

Report

[BTY/6/17/7]

Lion

24th June 1916.

Confidential

Sir,

In furtherance of our advanced report, we have the honour to forward some additional remarks on various points of interest gathered from the ships of the Battle-Cruiser Fleet and 5th Battle Squadron.

1. NOTES ON ENEMY'S GUNNERY

The general impression is that at first fire was very rapid, and accurate for range, but frequently bad for line, the spread was as a rule very small. It appears to be uncertain whether the spread was not occasionally opened out intentionally either by pairs of guns or singly; certainly in some cases the enemy fired salvoes in pairs of turrets. In this connection it is interesting to note that no ship which survived the action appears to have been hit by a complete salvo, but on several occasions ships were undoubtedly hit by two shell in one salvo which struck within a few feet of each other.

Evidence shows that both instantaneous salvoes and some form of very rapid ripple were in use. It appears that one ship at least fired by individual when damaged. The light cruisers certainly fired by director.

Evidence is very inconclusive as to what extent the enemy's early hitting and range keeping were dependent on the accuracy of their rangefinders, but, undoubtedly, on some occasions the enemy's opening ranges were not accurate, and when our ships slightly altered course salvoes fell off and some time was taken in regaining the range.

Many officers noted the efficiency with which the enemy concentrated a rapid fire from more than two ships on a particular ship or on the turning point of our line.

The general impression is that the enemy's fire in the battle-cruiser action fell off gradually, but whether this was due to our fire, the conditions of light, or range, is quite uncertain. In the 2nd phase of the action the enemy's fire was undoubtedly slow and spasmodic, but the light conditions were then entirely reversed, and this is probably sufficient to account for this lack of response to our fire.

On the contrary it must be remembered that on 24th January the enemy, after being severely hit for a long time, suddenly increased his rate and accuracy of fire and never fell to pieces in any way.

Although heavy ships were infrequently hit by shell of small calibre, the enemy made no great use of their secondary armament, except against light cruisers and destroyers. There is no evidence as to whether their secondary armament was fired by director or not.

Rear Admiral 2nd Battle Cruiser Squadron, and the Captains of Valiant and New Zealand remark on the noticeably small splash made by the enemy's heavy shell.

2. SMOKE INTERFERENCE BY OUR OWN DESTROYERS

Some ships complain of interference from torpedo destroyers' smoke, and this raises the question as to whether the position of our submarine screen when cruising is a suitable one for action.

In the case of a High Speed Squadron, a position well ahead appears to meet requirements, for the higher the speed of the screened squadron the further ahead the screen can be placed to keep down submarines. Again, in such a position they are advantageously placed for delivering and countering torpedo craft attacks, and smoke interference will be reduced.

We recommend trials being made of the utility of our own destroyers making smoke on the disengaged side of the large ships to render them more difficult to range and spot on, especially in the event of the enemy having the advantage of the light. It should be possible to rapidly control this by signal.

3. GUNNERY INFORMATION

Heading Added for Continuity.

3. We consider it desirable that in the Senior Officer's ship of every squadron, heavy or light, there should be an experienced officer whose sole duty it is to keep the Senior Officer informed, during an action, on gunnery matters other than those upon which his attention is at the moment riveted. For example, the following are important points which can only be observed to the best purpose by some officer who has no other duty:-

(a) When at a suitable range for opening or re-opening fire.

(b) Whether the squadron is keeping at the desired fighting range from the enemy.

(c) The general effect of our own and enemy's fire from time to time, and any necessary signals as to concentration of fire.

(d) When it is desirable to make use of destroyers' smoke.

In the heat of an action so many other points have to be considered that these may be overlooked unless an organisation for such details has been prepared; and this is especially the case when the action opens and attention tends to be distracted by watching the result of one's own gunfire.

4. DISTANCE APART IN LINE

There appears to be a very general opinion that increased distance up to four cables between ships would be an advantage under many conditions, and would give more freedom for altering course to avoid torpedoes and gunfire, and also under bad conditions of smoke.

5. POSITION OF CONTROL OFFICERS

The opinion of Control Officers as to the best position from which to control is nearly equally divided. It is, however, pointed out that both in Lion on 24th January 1915 and in Warspite on 31st May 1916, a heavy concentrated fire absolutely prevented any view from the gun control tower, and control from this position was impossible. It is therefore recommended that all ships should develop the use of their foretops as, at least, an equally important position as the gun control tower, and that all ships should attach the greatest importance to the development of this position both as regards protection and communication, and that this point should be considered in future construction.

6. AID TO SPOTTER DEVICE

Whenever the target was difficult to distinguish, due to visibility, in ships controlled from aloft, an 'aid to spotter' device was proved essential. In ships controlled from the gun control tower, Evershed's Training Indicators, where fitted, met requirements—if not fitted between the control tower and director tower, immediate instalment should be provided for.

7. EXCHANGE OF INFORMATION BETWEEN CONTROL OFFICERS

Communication between control positions in action was not made use of; those ships which attempted to do so state they were unable to get answers to their signals. It appears from this that the want of the information was felt by some ships. It is therefore recommended that the intercommunication should be the responsible duty of the Assistant Control Officer, where there is one, and that he should continuously communicate by arc lamp the range and the rate (but not the deflection) to the ship to which it is likely to be of most value. The necessity of avoiding time lag is emphasised. The enemy ship fired at should continue to be indicated as at present. Attention should be drawn to G.F.G.O No 65.

8. FATIGUE OF CONTROL OFFICERS, etc.

Fatigue or eyestrain of either Control Officers, Director Layers or Range Takers was not experienced to any inconvenient extent; but ships were seldom continuously engaged for more than three-quarters of an hour.

9. STATE OF CONTROL INSTRUMENTS

Reports show that control instruments generally were unaffected by the action — only one rangefinder being reported as getting seriously out of adjustment.

10. DIRECTOR FIRING GEAR

That director firing is absolutely essential in all light cruisers is the unanimous opinion as the result of the action. The reasons are:—

(a) To prevent our light cruisers being outranged by German light cruisers as occurred frequently on 31st May.

(b) Efficient direction of armament for training both day and night.

(c) Use in rough weather.

11. COMMUNICATIONS

In some cases further extension of communications has been advocated, but as this does not apply to all ships it is considered that Admirals Commanding Squadrons should be instructed to take the necessary action.

12. RANGE CORRECTORS

The range corrector was not used by any ship. This is doubtless due to opinions formed in peace practices at comparatively short ranges and under easier conditions, when the corrections were consequently small. The Committee consider that at the very much greater ranges and more difficult conditions that we now have to contend with, these corrections being greatly increased, must not be neglected if early hitting is to be established. This should be pointed out to the Fleet, and the use of the range corrector insisted upon, all ships being supplied.

13. ALLOWANCE FOR LOSS OF M.V.

The majority of ships made continuous allowance for loss of M.V. during the action. It is considered most important that this should be arranged for on the dip corrector scales in all ships.

14. USE OF AIRCRAFT

It is recommended that immediate use should be made of existing aircraft with the B.C.F. to practise passing information as to movements of enemy ships for the use of the Control Officer.

15. LESSONS TO BE LEARNT FROM NIGHT ACTIONS BETWEEN LIGHT CRUISERS ONLY

The situation experienced by the 2nd L.C.S. on the night of 31st May was approximately as follows. Two forces approached on converging courses, the enemy being to Westward could be seen but, there being doubt as to their identity, a short period elapsed trying without success to identify them, the challenge was then made but shortly after it was started enemy made compass sign by flashing lamp and switched on a combination of coloured lights at the masthead. Southampton then switched on searchlights and opened fire, upon which the whole of the enemy line (five ships) did the same. The other three ships of 2nd L.C.S. did not switch on searchlights but used the enemy light as a point of aim. The German lights, were high, widely separated and were on their object before switching on, and appeared to be controlled by Director and Master Switch.

Not more than two lights appeared to be used in any ship. Enemy appeared to fire at and between our searchlights, as practically all the hits in Southampton were made between them. It appears that all five enemy ships concentrated on the Southampton and the second ship Dublin, whereas the other two ships were not hit and were able to develop a very effective fire. As far as can be ascertained, fire was opened by both squadrons at the same moment. Three of the Southampton's guns probably opened at the wrong ship. The engagement lasted for about 3 1/2 minutes, the enemy using 'rapid independent'.

On these facts the Committee make the following recommendations:—

(a) The enemy's recognition signals were instantaneous while ours required a long signal, which admits of no action being taken until a similarly long reply has been made, and failing such reply there is bound to be some slight indecisive pause before opening fire. This interval may be of the greatest value to the enemy to complete his preparations before attacking. The question of recognition signals therefore requires reconsideration.

(b) It is considered essential that all ships should extemporise arrangements for training their searchlights as well as their guns dead on to a suspicious vessel, ready for instant attack, before making the challenge.

(c) Use of searchlights

(1) Lights should never be switched on if it can be avoided, thus denying the enemy a defined point of aim, whilst firing at his lights if he uses them, remembering that his lights are high. (vide Jane, 1914) [sic]

(2) If searchlights must be used, then in one position only; the use of two searchlights widely separated gives away the position of the ship and her alterations of course.

(3) As searchlights form a focus for enemy fire, those on the Bridge should not be used if it can be avoided.

(4) It appears that the best position for our own single searchlight would be right aft. A portable mounting could be used in calm weather.

(5) Searchlights should be fitted high up with the operators beneath them and suitably protected against splinters.

(d) The method of firing recommended to be employed is training by director, with individual laying. Undoubtedly some form of indirect training is essential.

(e) Spare lengths of flexible voicepipes for repairs to communications should be supplied to light cruisers as to battleships.

(f) Open sights fitted on the side of gun shields were of the greatest value in getting and keeping guns on the target. These should be fitted in all light cruisers.

16. EFFECT OF OWN SHELL

Bearing out the experience of previous actions, hits with heavy shell were seldom seen, especially with Lyddite A. P., which constituted the chief proportion of shell fired from battle-cruisers. Lyddite Common, especially from light cruisers, shewed up well. Some ships ranged with C.P.C. and this practice of changing the Committee do not consider promotes hitting.

17. SYMPATHETIC DETONATION OF LYDDITE SHELL

No case occurred of our own shell being detonated to enemy's fire, although in three ships shell burst within a few feet of them, and in some cases the projectiles were dented and driving bands cut.

18. SAFETY PINS OF LYDDITE COMMON

Most of the ships which fired Lyddite Common (both turret and light guns) experienced difficulty in extracting the safety pins; in a few cases shell were fired with the cap on, owing to the pins breaking, although pliers were used. Pliers in most cases met the difficulty.

19. ENEMY'S SHELL

There is no conclusive evidence that shrapnel shell were used. Star shell were undoubtedly used by some ships as night, generally before switching on searchlights. Enemy fired Very's lights during duty action continually, but for what purpose is not known.

20. GUN TUBES

Remarkably few missfires were caused by defective V.S. tubes.

21. SUPPLY OF SPARE PARTS

It is pointed out that no spare gear is supplied for the director. Spare parts as follows should be supplied to each gun, observing that serious delays occurred in one ship through lack of them:— Box slide, electric lock, and vent. bit to each turret gun.

In one ship the supply of 3 1/8" flexible voicepipe was found of the utmost value in effecting rapid repair of communications.

22. CHOKED VENT

A serious case of this occurred in one ship, a wad of shalloon and silk cloth choking vent so effectually that the mushroom head had to be shifted.

23. FLASH DOORS, Etc.

It is strongly recommended that the existing flash doors of the marking position in working chamber should be actuated by the transfer rammer heads instead of by the gunloading cage, and that this alteration should be hastened as much as possible in 13.5" mountings and, where applicable, in 12" mountings.

It is strongly recommended that the clearance between the trunk and the floor of the walking pipe space should be screened by strong flash plates, fitted so as to prevent the flash of a shell penetrating the turret armour going down from the turret, but so as to allow escape of gas pressures from the Handing Room.

As regards turret handing room hatches, it is a very debateable point whether these should be securely closed or not. In 'Q' turret of Lion it was open and relieved the pressure set up by the explosion of several full charges in the handing room: if this hatch had been closed it is probable the magazine bulkheads would have been blown in, observing that they are already distorted. We therefore recommend that handing room hatches should be closed, but not clipped, so as to prevent flame coming down and to relieve pressure going up.

24. DIRECTOR

Generally speaking, the existing director gear gave satisfaction. In one ship only is it reported as having occasionally 'got out of step', and larger fuses to stand more current are suggested.

The rocking trainers' sight proved valuable in one ship with a list.

One ship suggests that two-speed elevating gear to director sight would assist the layer considerably; with frequent alterations of course, ship gets a 'dragging' roll, and lies over for an appreciable time.

25. 12" BREECH MECHANISM

Serious delays having been caused through fracture of tube retainers in a ship with 12" Mk. X guns, it is strongly recommended that either spring link gear or hand operated locks should be supplied for these guns.