ANTI-SUBMARINE OPERATIONS
The previous chapters have dealt with the changes in organization
carried out at the Admiralty during the year 1917 largely with the
object of being able to deal more effectively with the submarine warfare
against merchant ships. Mention has also been made of the submarine
problem with which the Navy had to deal; particulars of the
anti-submarine and other work carried out will now be examined.
A very large proportion of the successful anti-submarine devices brought
into use during 1917, and continued throughout the year 1918, were the
outcome of the work of the Anti-Submarine Division of the Naval Staff,
and it is but just that the high value of this work should be recognized
when the history of the war comes to be written by future historians. As
has been stated in Chapter I, Rear-Admiral A.C. Duff, C.B., was the
original head of the division, with Captain F.C. Dreyer, C.B., Commander
Yeats Brown, and Commander Reginald Henderson as his immediate
assistants. Captain H.T. Walwyn took the place of Captain Dreyer on
March 1, 1917, when the latter officer became Director of Naval
Ordnance. When Admiral Duff was appointed Assistant Chief of the Naval
Staff, with a seat on the Board, in May, 1917, Captain W.W. Fisher,
C.B., became head of the division, which still remained one of the
divisions of the Staff working immediately under the A.C.N.S. It is to
these officers, with their most zealous, clever and efficient staff,
that the institution of many of the successful anti-submarine measures
is largely due. They were indefatigable in their search for new methods
and in working out and perfecting fresh schemes, and they kept their
minds open to _new ideas_. They received much valuable assistance from
the great civilian scientists who gave such ready help during the war,
the function of the naval officers working with the scientists being to
see that the effort was being directed along practical lines. They were
also greatly indebted to Captain Ryan, R.N., for the exceedingly
valuable work carried out by him at the experimental establishment at
Hawkcraig. Many brilliant ideas were due to Captain Ryan's clever brain.
I doubt whether the debt due to Admiral Duff and Captain Fisher and
their staff for their great work can ever be thoroughly appreciated, but
it is certainly my duty to mention it here since I am better able to
speak of it than any other person. In saying this I do not wish to
detract in the least from the value of the part performed by those to
whose lot it fell to put the actual schemes into operation. Without
them, of course, nothing could have been accomplished.
When the Anti-Submarine Division started in December, 1916, the earlier
devices to which attention was devoted were:
(1) The design and manufacture of howitzers firing shell fitted to
explode some 40 to 60 feet under water with which to attack submarines
when submerged.
(2) The introduction of a more suitable projectile for use against
submarines than that supplied at the time to the guns of destroyers and
patrol craft.
(3) The improvement of and great increase in the supply of smoke
apparatus for the screening of merchant ships from submarines attacking
by gunfire.
(4) A great increase in the number of depth charges supplied to
destroyers and other small craft.
(5) The development of the hydrophone for anti-submarine work, both from
ships and from shore stations.
(6) The introduction of the "Otter" for the protection of merchant ships
against mines.
(7) A very great improvement in the rapidity of arming merchant ships
defensively.
(8) The extended and organized use of air craft for anti-submarine work.
(9) A great development of the special service or decoy ship.
(10) The introduction of a form of net protection for merchant ships
against torpedo fire.
Other devices followed, many of which were the outcome of work in other
Admiralty Departments, particularly the Departments of the Director of
Naval Ordnance and the Director of Torpedoes and Mines, working in
conjunction with the Anti-Submarine or the Operations Division of the
Naval Staff. Some of the new features were the development of
depth-charge throwers, the manufacture and use of fast coastal
motor-boats for anti-submarine work, the production of mines of an
improved type for use especially against submarines, very considerable
developments in the use of minefields, especially deep minefields,
including persistent mining in the Heligoland Bight and the laying of a
complete minefield at varying depths in the Straits of Dover; also,
after the United States entered the war, the laying of a very extensive
minefield right across the northern part of the North Sea. The provision
of "flares" for illuminating minefields at night, and a system of
submarine detection by the use of electrical apparatus were also matters
which were taken up and pressed forward during 1917. During the year the
system of dazzle painting for merchant ships was brought into general
use.
On the operational side of the Naval Staff the work of dealing with
enemy submarines before they passed out of the North Sea was taken in
hand by organized hunting operations by destroyers and other patrol
craft, and by the more extended use offensively of our own submarines,
as vessels became available.
Considerable developments were effected in the matter of the control of
mercantile traffic, and much was done to train the personnel of the
mercantile marine in matters relating to submarine warfare.
Taking these subjects in detail, it will be of interest to examine the
progress made during the year.
HOWITZERS
The _howitzer_ as a weapon for use against the submarine when submerged
was almost non-existent at the beginning of 1917, only thirty
bomb-throwers, on the lines of trench-mortars, being on order. By April
of that year designs for seven different kinds of bomb-throwers and
howitzers had been prepared and approved, and orders placed for 1,006
weapons, of which number the first 41 were due for delivery in May. By
the end of May the number of bomb-throwers and howitzers on order had
been increased to 2,056, of eight different patterns. Over 1,000 of
these weapons fired a bomb or shell carrying a burster exceeding 90 lbs.
in weight, and with a range varying between 1,200 and 2,600 yards. Later
in the war, as we gained experience of the value of this form of attack,
heavier bombs were introduced for use in the existing bomb-throwers and
howitzers. The howitzer as an anti-submarine weapon was handicapped by
the comparatively small weight of the bursting charge of its shell. This
applied more particularly to the earlier patterns, and to inflict fatal
injury it was necessary to burst the shell in close proximity to the
submerged submarine. This weapon, although not very popular at first,
soon, however, proved its value, when employed both from patrol craft
and from merchant ships.
One curious instance occurred on March 28, 1918, of a merchant ship
being saved by a 7.5-inch howitzer. A torpedo was seen approaching at a
distance of some 600 yards, and it appeared certain to hit the ship. A
projectile fired from the howitzer exploded under water close to the
torpedo, deflected it from its course, and caused it to come to the
surface some 60 yards from the ship; a second projectile caused it to
stop, and apparently damaged the torpedo, which when picked up by an
escorting vessel was found to be minus its head.
Delivery of howitzers commenced in June, 1917, and continued as follows:
Total completed,
No. of Howitzers including those
Date. actually issued. under proof.
July 24, 1917 35 48
October 1, 1917 92 167
December 10, 1917 377 422
The slow rate of delivery, in spite of constant pressure, which is shown
by these figures gives some idea of the time required to bring new
devices into existence.
PROJECTILE FOR USE AGAINST SUBMARINES
In January, 1917, the Director of Naval Ordnance was requested by the
Anti-Submarine Division of the Naval Staff to carry out trials against a
target representing the hull of a German submarine, so far as the
details were known to us, to ascertain _the most suitable type of
projectile_ amongst those then in existence for the attack of submarines
by guns of 4.7-inch calibre and below.
The results were published to the Fleet in March, 1917. They afforded
some useful knowledge and demonstrated the ineffectiveness of some of
the shells and fuses commonly in use against submarines from 12-pounder
guns, the weapon with which so many of our patrol craft were armed. The
target at which the shell was fired did not, however, fully represent a
German submarine under the conditions of service. The trials were
therefore continued, and as a result, in June, 1917, a further order was
issued to the Fleet, giving directions as to the type of projectile to
be used against submarines from all natures of guns, pending the
introduction of delay action fuses for the smaller guns; this was the
temporary solution of the difficulty until a new type of shell evolved
from the experience gained at the trials could be produced and issued.
The trials, which were exhaustive, were pressed forward vigorously and
continuously throughout the year 1917, and meanwhile more accurate
information as to the exact form of the hull and the thickness of the
plating of German submarines became available. Early in 1918 the first
supplies of the new fuses were ready for issue.
SMOKE APPARATUS
The earlier _smoke apparatus_ for supply to merchant ships was designed
towards the end of 1916.
One description of smoke apparatus consisted of an arrangement for
burning phosphorus at the stern of a ship; in other cases firework
composition and other chemicals were used. A dense smoke cloud was thus
formed, and, with the wind in a suitable direction, a vessel could hide
her movements from an enemy submarine or other vessel, and thus screen
herself from accurate shell fire.
In another form the apparatus was thrown overboard and formed a smoke
cloud on the water.
The rate of supply of sets of the smoke apparatus to ships is shown by
the following figures:
April 1, 1917 - 1,372 sets
July 3, 1917 - 2,563 sets
October 5, 1917 - 3,445 sets
November 26, 1917 - 3,976 sets
DEPTH CHARGES
_Depth charges_, as supplied to ships in 1917, were of two patterns:
one, Type D, contained a charge of 300 lb. of T.N.T., and the other,
Type D*, carried 120 lb. of T.N.T. At the commencement of 1917 the
allowance to ships was two of Type D and two of Type D*, and the supply
was insufficient at that time to keep up the stock required to maintain
on board four per destroyer, the number for which they were fitted, or
to supply all trawlers and other patrol craft with their allowance. The
great value of the depth charge as a weapon against submarines, and the
large number that were required for successful attack, became apparent
early in 1917, and the allowance was increased. Difficulty was
experienced throughout the year in maintaining adequate stocks owing to
the shortage of labour and the many demands on our industries made by
the war, but the improvement is shown by the fact that while the average
output _per week_ of depth charges was only 140 in July, it had become
over 500 by October, and that by the end of December it was raised to
over 800, and was still increasing very rapidly. As a consequence, early
in 1918 it was found possible to increase the supply very largely, as
many as 30 to 40 per destroyer being carried.
Improvements in the details of depth charges were effected during 1917.
One such improvement was the introduction of a pistol capable of firing
at much greater depths than had been in use before. The result was that
all vessels, whether fast or slow, could safely use the 300-lb. depth
charge if set to a sufficient depth. This led to the abolition of the
Type D* charges and the universal supply of Type D.
In spite of the difficulties of dropping depth charges so close to
submarines as to damage them sufficiently to cause them to come to the
surface, very good results were obtained from their use when destroyers
carried enough to form, so to speak, a ring round the assumed position
at which the submarine had dived. In order to encourage scientific
attack on submarines, a system of depth charge "Battle Practice" was
introduced towards the end of 1917.
It is as well to correct a common misapprehension as to the value of
depth charges in destroying submarines.
Many people held very exaggerated ideas on this subject, even to the
extent of supposing that a depth charge would destroy a submarine if
dropped within several hundred yards of her. This is, unfortunately,
very far indeed from being the case; it is, on the contrary, necessary
to explode the charge near the submarine in order to effect destruction.
Taking the depth charge with 300 lb. weight of explosive, ordinarily
supplied to destroyers in 1917, it was necessary to explode it within
fourteen feet of a submarine to ensure destruction; at distances up to
about twenty-eight feet from the hull the depth charge might be expected
to disable a submarine to the extent of forcing her to the surface, when
she could be sunk by gun-fire or rammed, and at distances up to sixty
feet the moral effect on the crew would be considerable and _might_
force the submarine to the surface.
A consideration of these figures will show that it was necessary for a
vessel attacking a submarine with depth charges to drop them in very
close proximity, and the first obvious difficulty was to ascertain the
position of a submarine that had dived and was out of sight.
Unless, therefore, the attacking vessel was fairly close to the
submarine at the moment of the latter diving there was but little chance
of the attack being successful.
HYDROPHONES
The _Hydrophone_, for use in locating submerged submarines, although
first evolved in 1915, was in its infancy, so far as supply to ships was
concerned, at the commencement of 1917. Experiments were being carried
out by the Board of Invention and Research at Harwich, and by Captain
Ryan, R.N., at Hawkcraig, and although very useful results had been
obtained and a considerable number of shore stations as well as some
patrol vessels had been fitted with hydrophones, which had a listening
range of one or two miles, all the devices for use afloat suffered from
the disadvantage that it was not possible to use them whilst the ship
carrying them was moving, since the noise of the vessel's own machinery
and of the water passing along the side prevented the noise made by
other vessels being located. What was required was a listening
instrument that could be used by a ship moving at least at slow speed,
otherwise the ship carrying the hydrophone was herself, when stopped, an
easy target for the submarine's torpedo. It was also essential, before
an attack could be delivered, to be able to locate the _direction_ of
the enemy submarine, and prior to 1917 all that these instruments showed
was the presence of a submarine somewhere in the vicinity.
Much research and experimental work was carried out during the year 1917
under the encouragement and supervision of the Anti-Submarine Division
of the Naval Staff. Two hydrophones were invented in the early part of
1917, one by Captain Ryan, R.N., and one by the Board of Invention and
Research, which could be used from ships at very slow speed and which
gave some indication of the _direction_ of the sound; finally, in the
summer of 1917, the ability and patience of one inventor, Mr. Nash, were
rewarded, and an instrument was devised termed the "fish" hydrophone
which to a considerable extent fulfilled the required conditions. Mr.
Nash, whose invention had been considered but not adopted by the Board
of Invention and Research before he brought it to the Anti-Submarine
Division of the Naval Staff, laboured under many difficulties with the
greatest energy and perseverance; various modifications in the design
were effected until, in October, 1917, the instrument was pronounced
satisfactory and supplies were put in hand.
The next step was to fit the "fish" hydrophone in certain auxiliary
patrol vessels as well as some destroyers, "P" boats and motor launches,
to enter and train men to work it, and finally to organize these vessels
into "submarine hunting flotillas," drill them, and then set them to
their task.
This work, which occupied some time, was carried out at Portland, where
a regular establishment was set up for developing the "fish" hydrophone
and for organizing and training the "hunting flotillas" in its use. A
considerable amount of training in the use of the hydrophone was
required before men became efficient, and only those with a very keen
sense of hearing were suited to the work. The chances of the success of
the hunting flotillas had been promising in the early experiments, and
the fitting out of patrol craft and organizing and drilling them,
proceeded as rapidly as the vessels could be obtained, but largely owing
to the slow production of trawlers it was not until November that the
first hunting flotilla fitted with the "fish" hydrophone was actually at
work. The progress made after this date is illustrated by the fact that
in December, 1917, a division of drifters, with a "P" boat, fitted with
this "fish" hydrophone hunted an enemy submarine for seven hours during
darkness, covering a distance of fifty miles, kept touch with her by
sound throughout this period, and finished by dropping depth charges in
apparently the correct position, since a strong smell of oil fuel
resulted and nothing further could be heard of the submarine, although
the drifters listened for several hours. On another occasion in the same
month a division of drifters hunted a submarine for five hours. The
number of hydrophones was increased as rapidly as possible until by the
end of the year the system was in full operation within a limited area,
and only required expansion to work, as was intended, on a large scale
in the North Sea and the English Channel.
Meanwhile during 1917 _directional_ hydrophones, which had been
successfully produced both by Captain Ryan and by the Board of Invention
and Research, had been fitted to patrol craft in large numbers, and
"hunting flotillas" were operating in many areas. A good example of the
working of one of these flotillas occurred off Dartmouth in the summer
of 1918, when a division of motor launches fitted with the Mark II
hydrophone, under the general guidance of a destroyer, carried out a
successful attack on a German submarine. Early in the afternoon one of
the motor launches dropped a depth charge on an oil patch, and shortly
afterwards one of the hydrophones picked up the sound of an internal
combustion engine; a line of depth charges was run on the bearing
indicated by the hydrophone. The motor launches and the destroyer
remained listening, until at about 6.0 P.M. a submarine came to the
surface not far from Motor Launch No. 135, which fired two rounds at the
submarine before the latter submerged. Other motor launches closed in,
and depth charges were dropped by them in close proximity to the wash of
the submarine. Oil came to the surface, and more depth charges were
dropped in large numbers on the spot for the ensuing forty-eight hours.
Eventually objects came to the surface clearly indicating the presence
of a submarine. Further charges were dropped, and an obstruction on the
bottom was located by means of a sweep. This engagement held peculiar
interest for me, since during my visit to Canada in the winter of 1919
the honour fell to me of presenting to a Canadian--Lieutenant G.L.
Cassady, R.N.V.R.--at Vancouver the Distinguished Service Cross awarded
him by His Majesty for his work in Motor Launch No. 135 on this
occasion.
_Motor Launches_ were organized into submarine hunting flotillas during
the year 1917. These vessels were equipped with the directional
hydrophone as soon as its utility was established, and were supplied
with depth charges. In the summer of 1917 four such hunting flotillas
were busy in the Channel; the work of one of these I have described
already, and they certainly contributed towards making the Channel an
uneasy place for submarine operations.
These results were, of course, greatly improved on in 1918, as the
numbers of ships fitted with the "fish" and other hydrophones increased
and further experience was gained.
The progress in supply of hydrophones is shown by the following table:
Supply of Directional
Date General Service Mark I and Shark Fin Fish
1917. Portable Type. Mark II. Type. Type.
Jul 31 2,750 500 - -
Aug 31 2,750 700 - -
Sep 30 2,750 850 - -
Oct 31 3,500 1,000 - -
Dec 31 3,680 1,950 870 37
HYDROPHONE STATIONS AND TRAINING SCHOOLS
At the beginning of 1917 four _shore hydrophone stations_ were in use.
During the year eight additional stations were completed and several
more were nearing completion. The first step necessary was a
considerable increase in the instructional facilities for training
listeners both for the increased number of shore stations and for the
large number of vessels that were fitted for hydrophone work during the
year.
The greater part of this training took place at the establishment at
Hawkcraig, near Rosyth, at which Captain Ryan, R.N., carried out so much
exceedingly valuable work during the war. I am not able to give exact
figures of the number of officers and men who were instructed in
hydrophone work either at Hawkcraig or at other stations by instructors
sent from Hawkcraig, but the total was certainly upwards of 1,000
officers and 2,000 men. In addition to this extensive instructional work
the development of the whole system of detecting the presence of
submarines by sound is very largely due to the work originally carried
out at Hawkcraig by Captain Ryan.
The first hydrophone station which was established in the spring of 1915
was from Oxcars Lighthouse in the Firth of Forth; it was later in the
year transferred to Inchcolm. Experimental work under Captain Ryan
continued at Hawkcraig during 1915, and in 1916 a section of the Board
of Invention and Research went to Hawkcraig to work in conjunction with
him. This station produced the Mark II directional hydrophone of which
large numbers were ordered in 1917 for use in patrol craft. It was a
great improvement on any hydrophone instrument previously in use.
Hawkcraig also produced the directional plates fitted to our submarines,
as well as many other inventions used in detecting the presence of
submarines.
In addition to the work at Hawkcraig an experimental station under the
Board of Invention and Research was established near Harwich in January,
1917. The Mark I directional hydrophone was designed at this
establishment in 1917, and other exceedingly valuable work was carried
out there connected with the detection of submarines.
At Malta an experimental station, with a hydrophone training school, was
started in the autumn of 1917, and good work was done both there and at
a hydrophone station established to the southward of Otranto at about
the same time, as well as at a hydrophone training school started at
Gallipoli at the end of the year.
"OTTERS" AND PARAVANES
_The "Otter" system_ of defence of merchant ships against mines was
devised by Lieutenant Dennis Burney, D.S.O., R.N. (a son of Admiral Sir
Cecil Burney), and was on similar lines to his valuable invention for
the protection of warships. The latter system had been introduced into
the Grand Fleet in 1916, although for a long period considerable
opposition existed against its general adoption, partly on account of
the difficulties experienced in its early days of development, and
partly owing to the extensive outlay involved in fitting all ships.
However, this opposition was eventually overcome, and before the end of
the war the system had very amply justified itself by saving a large
number of warships from destruction by mines. It was computed that there
were at least fifty cases during the war in which paravanes fitted to
warships had cut the moorings of mines, thus possibly saving the ships.
It must also be borne in mind that the cutting of the moorings of a mine
and the bringing of it to the surface may disclose the presence of an
hitherto unknown minefield, and thus save other ships.
Similarly, the "Otter" defence in its early stages was not introduced
without opposition, but again all difficulties were overcome, and the
rate of progress in its use is shown in the following statement giving
the number of British merchant ships fitted with it at different periods
of 1917:
By July 1, 95 ships had been fitted.
By September 1, 294 ships had been fitted.
By December 1, 900 ships had been fitted.
The system was also extended to foreign merchant ships, and supplies of
"Otters" were sent abroad for this purpose.
A considerable number of merchant ships were known to have been saved
from destruction by mine by the use of this system.
DEFENSIVE ARMING OF MERCHANT SHIPS
The _defensive arming_ of merchant ships was a matter which was pressed
forward with great energy and rapidity during the year 1917. The matter
was taken up with the Cabinet immediately on the formation of the Board
of Admiralty presided over by Sir Edward Carson, and arrangements made
for obtaining a considerable number of guns from the War Office, from
Japan, and from France, besides surrendering some guns from the
secondary and anti-torpedo boat armament of our own men-of-war,
principally those of the older type, pending the manufacture of large
numbers of guns for the purpose. Orders for some 4,200 guns were placed
by Captain Dreyer, the Director of Naval Ordnance, with our own gun
makers in March, April and May, 1917, in addition to nearly 3,000 guns
already on order for this purpose; 400 90-m.m. guns were obtained from
France, the mountings being made in England. Special arrangements were
also made by Captain Dreyer for the rapid manufacture of all guns,
including the provision of the material and of extra manufacturing
plant.
These orders for 4,200 guns and the orders for 2,026 howitzers placed at
the same time brought the total number of guns and howitzers under
manufacture in England for naval and merchant service purposes in May,
1917, up to the high figure of 10,761.
At the end of the year 1916 the total number of merchant ships that had
been armed since the commencement of the war (excluding those which were
working under the White Ensign and which had received _offensive_
armaments) was 1,420. Of this number, 83 had been lost.
During the first six months of 1917 armaments were provided for an
additional 1,581 ships, and during the last six months of that year a
further total of 1,406 ships were provided with guns, an aggregate
number of 2,987 ships being thus furnished with armaments during the
year. This total was exclusive of howitzers.
The progress of the work is shown by the following figures:
Number or guns that had been
Date. provided for British Merchant
Ships excluding Howitzers.
January 1, 1917 1,420
April 1, 1917 2,181
July 1, 1917 3,001
October 1, 1917 3,763
January 1, 1918 4,407
The figures given include the guns mounted in ships that were lost
through enemy action or from marine risks.
It should be stated that the large majority of the guns manufactured
during 1917 were 12-pounders or larger guns, as experience had shown
that smaller weapons were usually outranged by those carried in
submarines, and the projectiles of even the 12-pounder were smaller than
was desirable. Of the 2,987 new guns mounted in merchant ships during
the year 1917 only 190 were smaller than 12-pounders.
AIRCRAFT FOR ANTI-SUBMARINE WORK
_Anti-submarine work by aircraft_ was already in operation round our
coasts by the beginning of 1917, and during the year the increase in
numbers and improvement in types of machines rendered possible
considerable expansion of the work. Closer co-operation between surface
vessels and aircraft was also secured, and as the convoy system was
extended aircraft were used both for escort and observation work, as
well as for attack on submarines. For actual escort work airships were
superior to heavier-than-air machines owing to their greater radius of
action, whilst for offensive work against a submarine that had been
sighted the high speed of the seaplane or aeroplane was of great value.
In 1916 and the early part of 1917 we were but ill provided with
aircraft suitable for anti-submarine operations at any considerable
distance from the coast, and such aircraft as we possessed did not carry
sufficiently powerful bombs to be very effective in attacking
submarines, although they were of use in forcing these vessels to
submerge and occasionally in bringing our surface craft to the spot to
press home the attack.
The Royal Naval Air Service, under Commodore Godfrey Paine, devoted much
energy to the provision of suitable aircraft, and the anti-submarine
side of the Naval Staff co-operated in the matter of their organization;
with the advent of the large "America" type of seaplane and the
Handley-Page type of aeroplane, both of which carried heavy bombs,
successful attacks on enemy submarines became more frequent. They were
assisted by the airships, particularly those of the larger type.
Improvements which were effected in signalling arrangements between
ships and aircraft were instrumental in adding greatly to their
efficiency, and by the early summer of 1917 aircraft had commenced to
play an important part in the war against submarines and in the
protection of trade.
Thereafter progress became rapid, as the following figures show:
In June, 1917, aeroplanes and seaplanes patrolling for anti-submarine
operations covered 75,000 miles, sighted 17 submarines, and were able to
attack 7 of them.
In September, 1917, the distance covered by anti-submarine patrols of
aeroplanes and seaplanes was 91,000 miles, 25 submarines were sighted,
of which 18 were attacked.
In the four weeks ending December 8, 1917, in spite of the much shorter
days and the far less favourable flying weather experienced, the mileage
covered was again 91,000 miles; 17 submarines were sighted, of which 11
were attacked during this period.
As regards airships the figures again show the increased anti-submarine
work carried out:
In June, 1917, airships engaged in anti-submarine patrol covered 53,000
miles, sighted and attacked 1 submarine.
In September, 1917, they covered 83,000 miles, and sighted 8 submarines,
of which 5 were attacked.
In the four weeks ending December 8, 1917, they covered 50,000 miles,
sighted 6 submarines, and attacked 5 of them.
The airships were more affected by short days, and particularly by bad
weather, than the heavier than air craft, and the fact that they covered
practically the same mileage in the winter days of December as in the
summer days of June shows clearly the development that took place in the
interval.
During the whole of 1917 it was estimated that our heavier than air
craft sighted 135 submarines and attacked 85 of them, and our lighter
than air craft sighted 26 and attacked 15. The figures given in Chapter
IX of the number of submarines sunk during the war by aircraft (viz. 7
as a minimum), when compared with the number of attacks during 1917
alone suggest the difficulties of successful attack.
In September, 1917, as extensive a programme as was consistent with
manufacturing capabilities, in view of the enormous demands of the Army,
was drawn up by the Naval Staff for the development of aircraft for
anti-submarine operations during 1918.
The main developments were in machines of the large "America" type and
heavy bombing machines for attacking enemy bases, as well as other
anti-submarine machines and aircraft for use with the Grand Fleet.
Included in the anti-submarine operations of aircraft during 1917 were
the bombing attacks on Bruges, since the German submarines and the
shelters in which they took refuge were part of the objective.
These attacks were carried out from the aerodrome established by the
Royal Naval Air Service at Dunkirk. During 1917 the Naval Air Forces of
the Dover Command, which included the squadrons at Dunkirk, were under
the command of Captain C.L. Lambe, R.N., and the operations of this
force were of a very strenuous character and of the utmost value.
Bombing operations prior to the year of 1917 had been carried out by
various types of machines, but the introduction of the Handley-Page
aeroplanes in the spring of 1917 enabled a much greater weight of
bombs--viz. some 1,500 lbs.--to be carried than had hitherto been
possible. These machines were generally used for night bombing, and the
weight of bombs dropped on the enemy bases in Belgium rose with great
rapidity as machines of the Handley-Page type were delivered, as did the
number of nights on which attacks were made. It was no uncommon
occurrence during the autumn of 1917 for six to eight tons of bombs to
be dropped in one night. I have not the figures for 1918, but feel no
doubt that with the great increase in aircraft that became possible
during that year this performance was constantly exceeded.
SPECIAL SERVICE OR DECOY SHIPS
The story of the work of these vessels constitutes a record of
gallantry, endurance and discipline which has never been surpassed
afloat or ashore. The earliest vessels were fitted out during the year
1915 at Scapa, Rosyth, Queenstown and other ports, and from the very
first it was apparent that they would win for themselves a place in
history. The earliest success against an enemy submarine by one of these
vessels was achieved by the _Prince Charles_, fitted out at Scapa, and
commanded by Lieutenant Mark-Wardlaw, an officer on the Staff of Admiral
Sir Stanley Colville, then Admiral Commanding the Orkneys and Shetlands.
In the early months of 1917 it was decided to augment greatly the force
of these special service vessels, and steps were taken to organize a
separate Admiralty Department for the work. Special experience was
needed, both for the selection of suitable ships and for fitting them
out, and care was taken to select officers who had been personally
connected with the work during the war; the advice of successful
commanders of decoy ships was also utilized. At the head was Captain
Alexander Farrington, under whose directions several ships had been
fitted out at Scapa with great ingenuity and success. Every class of
ship was brought into the service: steam cargo vessels, trawlers,
drifters, sailing ships, ketches, and sloops specially designed to have
the appearance of cargo ships. These latter vessels were known as
"convoy sloops" to distinguish them from the ordinary sloop. Their
design, which was very clever, had been prepared in 1916 by Sir Eustace
T. D'Eyncourt, the Director of Naval Construction. The enemy submarine
commanders, however, became so wary owing to the successes of decoy
ships that they would not come to the surface until they had inspected
ships very closely in the submerged condition, and the fine lines of the
convoy sloops gave them away under close inspection.
In the early spring of 1917 the Director of Naval Construction was asked
whether the "P" class of patrol boats then under construction could be
altered to work as decoy vessels, as owing to their light draught they
would be almost immune from torpedo attack.
A very good design was produced, and some of the later patrol boats were
converted and called "P Q's." These vessels had the appearance of small
merchant ships at a cursory glance. They would not, however, stand close
examination owing, again, to their fine lines, but being better sea
boats than the "P's," by reason of their greater freeboard, the design
was continued, and they met with considerable success against submarines
(especially in the Irish Sea) by ramming and depth charge tactics, the
submarines when submerged probably not realizing when observing the "P
Q.'s" through a periscope the speed of which they were capable.
During 1917, when the unrestricted submarine warfare was in progress,
many of the decoy vessels were fitted with torpedo tubes, either above
water or submerged, since, as the submarine commanders became more wary,
they showed great dislike to coming to the surface sufficiently close to
merchant ships to admit of the gun armament being used with certainty of
success. A torpedo, on the other hand, could, of course, be used
effectively against a submarine whilst still submerged. The use also
became general of casks or cargoes of wood to give additional flotation
to decoy ships after being torpedoed, so as to prolong their life in
case the submarine should close near enough to allow of effective
gunfire.
Another ruse adopted was that of changing the disguise of a decoy ship
during the night, so that she could not be identified by a submarine
which had previously made an attack upon her. In all cases of disguise
or of changing disguise it was essential that the decoy ship should
assume the identity of some class of vessel likely to be met with in the
particular area in which she was working, and obviously the courses
steered were chosen with that object in view.
Again, since for success it was essential to induce the submarine to
come within close range so that the decoy ship's gunfire should be
immediately effective, it was necessary that her disguise should stand
the closest possible examination through the periscope of a submarine.
German submarine commanders, after a short experience of decoy ships,
were most careful not to bring their vessels to the surface in proximity
to craft that were apparently merchant ships until they had subjected
them to the sharpest scrutiny at short range through the periscope, and
the usual practice of an experienced submarine commander was to steer
round the ship, keeping submerged all the time.
Not only was it essential that there should be no sign of an armament in
the decoy ship, or a man-of-war-like appearance in any respect, but when
the "panic" signal was made to lead the submarine commander to think
that his attack had succeeded, precautions had to be taken against the
presence of more than the ordinary number of men in the boats lowered
and sent away with the supposed whole ship's company; also the sight of
any men left on board would at once betray the real character of the
decoy ship and result in the disappearance of the submarine and the
probable sinking of the disguised craft by torpedo fire.
During the late summer of 1917 it became evident that the submarine
commanders had become so suspicious of decoy craft that the chances of
success by the larger cargo vessels were not sufficient to justify any
further addition to existing numbers in view of the increasing shortage
of shipping; a considerable fleet of steamers building for this purpose
was therefore diverted to trade purposes. The number of smaller vessels,
particularly sailing craft, was, however, increased especially in
Mediterranean waters where they had not been previously operating on an
extensive scale.
It is impossible to close these remarks on this class of vessel without
testifying once more to the splendid gallantry, self-sacrifice, skilful
resource and magnificent discipline shown by those on board. This is
illustrated by descriptions of a few typical actions fought during 1917.
The first which I relate took place on February 17, 1917, when a decoy
vessel, a steamship armed with five 12-pounder guns, commanded by that
most gallant officer, Captain Gordon Campbell, R.N., was torpedoed by a
submarine in a position Lat. 51.34 N., Long. 11.23 W.
Captain Campbell saw the torpedo coming and manoeuvred to try and avoid
being hit in the engine-room, but as he purposely always selected a very
slow ship for decoy work his attempt was only partially successful and
the engine-room began to fill. No signal for assistance was made,
however, as Captain Campbell feared that such a signal might bring
another vessel on the scene and this would naturally scare the submarine
away. The usual procedure of abandoning the ship in the boats with every
appearance of haste was carried out, only sufficient hands remaining
hidden on board to work the guns. The periscope of the submarine was
next sighted on the quarter within 200 or 300 yards, and she came slowly
past the ship still submerged and evidently examining the vessel closely
through the periscope. She passed within a few yards of the ship, then
crossed the bow and came to the surface about 200 yards off and passed
down the port side again close to. Captain Campbell waited until every
gun would bear before giving the signal for "action." The decoy ship's
true character was then revealed; concealed gunports were thrown open;
colours were hoisted, and a hot fire opened from all guns. The submarine
was hit at once and continued to be hit so rapidly that it was evidently
impossible for her to submerge. She sank in a very short time. One
officer and one man were picked up. A signal was then made for
assistance and help arrived within a couple of hours. The decoy ship was
rapidly filling, but efforts were made to tow her into port, and with
the greatest difficulty, and entirely owing to the splendid manner in
which all hands stuck to the work, she was brought into Berehaven with
her stern under water thirty-six hours later and beached. The great
restraint shown by Captain Campbell, in withholding fire as the
submarine passed her in a submerged condition, and the truly wonderful
discipline and steadiness and ingenuity which baffled so close an
examination of the ship were the outstanding features of this great
exploit.
On April 22, 1917, a decoy ship known as "Q22," a small sailing vessel
with auxiliary power, armed with two 12-pounder guns, and commanded by
Lieutenant Irvine, R.N.R., while in a position about fifty miles south
of Kinsale Head, sighted a submarine on the surface which opened fire
immediately at a range of about 4,000 yards. The fire was accurate and
the decoy ship was hit frequently, two men being killed and four wounded
in a few minutes and the vessel considerably damaged. As further
concealment appeared useless the guns were then unmasked and the fire
returned with apparently good results, several hits being claimed. The
enemy's fire then fell off in accuracy and she increased the range, and
after about one and a half hours' fighting the light became too bad to
continue the action. It was thought that the submarine was sunk, but
there was no positive evidence of sinking.
On April 30, 1917, a decoy ship--H.M.S. _Prize_--a small schooner with
auxiliary power, armed with two 12-pounder guns and commanded by
Lieutenant W.E. Sanders, R.N.R., a New Zealand officer, sighted, when in
position Lat. 49.44 N., Long. 11.42 W., a submarine about two miles away
on the port beam at 8.30 P.M. At 8.45 P.M. the submarine opened fire on
the _Prize_ and the "abandon ship" party left in a small boat. The
submarine gradually approached, continuing to pour in a heavy fire and
making two hits on the _Prize_ which put the motor out of action,
wrecked the wireless office, and caused much internal damage besides
letting a great deal of water into the ship.
The crew of the _Prize_ remained quietly hidden at their concealed guns
throughout this punishment, which continued for forty minutes as the
submarine closed, coming up from right astern, a position no doubt which
she considered one of safety. When close to she sheered off and passed
to the port beam at a distance of about one hundred yards. At this
moment Lieutenant Sanders gave the order for "action." The guns were
exposed and a devastating fire opened at point blank range, but not
before the submarine had fired both her guns, obtaining two more hits,
and wounding several of the crew of the _Prize_. The first shell fired
from the _Prize_ hit the foremost gun of the submarine and blew it
overboard, and a later shot knocked away the conning tower. The
submarine went ahead and the _Prize_ tried to follow, but the damage to
her motor prevented much movement. The firing continued as the submarine
moved away, and after an interval she appeared to be on fire and to
sink. This occurred shortly after 9.0 P.M., when it was nearly dark. The
_Prize_ sent her boats to pick up survivors, three being taken out of
the water, including the commander and one other officer. The prisoners
on coming on board expressed their willingness to assist in taking the
_Prize_ into port. It did not at this time seem likely that she would
long remain afloat, but by great exertion and good seamanship the leaks
were got under to a sufficient extent to allow of the ship being kept
afloat by pumping. The prisoners gave considerable help, especially when
the ship caught fire whilst starting the motor again. On May 2 she met a
motor launch off the coast of Ireland and was towed into port. In spite
of the undoubted great damage to the submarine, damage confirmed by the
survivors, who were apparently blown overboard with the conning tower,
and who had no thought other than that she had been sunk, later
intelligence showed that she succeeded in reaching Germany in a very
disabled condition. This incident accentuated still further the
recurrent difficulty of making definite statements as to the fate of
enemy submarines, for the evidence in this case seemed absolutely
conclusive. The commander of the submarine was so impressed with the
conduct of the crew of the _Prize_ that when examined subsequently in
London he stated that he did not consider it any disgrace to have been
beaten by her, as he could not have believed it possible for any ship's
company belonging to any nation in the world to have been imbued with
such discipline as to stand the shelling to which he subjected the
_Prize_ without any sign being made which would give away her true
character.
Lieut.-Commander Sanders was awarded the Victoria Cross for his action
and many decorations were given to the officers and ship's company for
their conduct in the action. It was sad that so fine a commander and so
splendid a ship's company should have been lost a little later in action
with another submarine which she engaged unsuccessfully during daylight,
and which followed her in a submerged condition until nightfall and then
torpedoed her, all hands being lost.
It was my privilege during my visit to New Zealand in 1919 to unveil a
memorial to the gallant Sanders which was placed in his old school at
Takapuna, near Auckland.
On June 7, 1917, a decoy ship, the S.S. _Pargust_, armed with one 4-inch
gun, four 12-pounder guns and two torpedo tubes, commanded by Captain
Gordon Campbell, R.N., who had meanwhile been awarded the Victoria
Cross, was in a position Lat. 51.50 N., Long. 11.50 W., when a torpedo
hit the ship abreast the engine-room and in detonating made a hole
through which water poured, filling both engine-room and boiler-room.
The explosion of the torpedo also blew one of the boats to pieces. The
usual procedure of abandoning ship was carried out, and shortly after
the boats had left, the periscope of a submarine was sighted steering
for the port side. The submarine passed close under the stern, steered
to the starboard side, then recrossed the stern to the port side, and
when she was some fifty yards off on the port beam her conning tower
appeared on the surface and she steered to pass round the stern again
and towards one of the ship's boats on the starboard beam. She then came
completely to the surface within one hundred yards, and Captain Campbell
disclosed his true character, opened fire with all guns, hitting the
submarine at once and continuing to hit her until she sank. One officer
and one man were saved. The decoy ship lost one man killed, and one
officer was wounded by the explosion of the torpedo.
As in the case of the action on February 17 the distinguishing feature
of this exploit was the great restraint shown by Captain Campbell in
withholding his fire although his ship was so seriously damaged. The
gallantry and fine discipline of the ship's company, their good shooting
and splendid drill, contributed largely to the success. The decoy ship,
although seriously damaged, reached harbour.
On July 10, 1917, a decoy ship, H.M.S. _Glen_, a small schooner with
auxiliary power and armed with one 12-pounder and one 6-pounder gun,
commanded by Sub-Lieutenant K. Morris, R.N.R., was in a position about
forty miles south-west of Weymouth when a submarine was sighted on the
surface some three miles away. She closed to within two miles and opened
fire on the _Glen_. The usual practice of abandoning ship was followed,
the submarine closing during this operation to within half a mile and
remaining at that distance examining the _Glen_ for some time. After
about half an hour she went ahead and submerged, and then passed round
the ship at about 200 yards distance, examining her through the
periscope, finally coming to the surface about 50 yards off on the port
quarter. Almost immediately she again started to submerge, and fire was
at once opened. The submarine was hit three or four times before she
turned over on her side and disappeared. There was every reason to
believe that she had sunk, although no one was on deck when she
disappeared. No survivors were rescued.
The feature of this action was again the restraint shown by the
commanding officer of the _Glen_ and the excellent discipline of the
crew.
On August 8, 1917, the decoy ship H.M.S. _Dunraven_, in Lat. 48.0 N.,
Long. 7.37 W., armed with one 4-inch and four 12-pounder guns and two
torpedo tubes, commanded by Captain Gordon Campbell, V.C., R.N., sighted
a submarine on the surface some distance off. The submarine steered
towards the ship and submerged, and soon afterwards came to the surface
some two miles off and opened fire. The _Dunraven_, in her character of
a merchant ship, replied with an after gun, firing intentionally short,
made a smoke screen, and reduced speed slightly to allow the submarine
to close.
When the shells from the submarine began to fall close to the ship the
order to abandon her was given, and, as usual with the splendidly
trained ship's company working under Captain Campbell, the operation was
carried out with every appearance of disorder, one of the boats being
purposely left hanging vertical with only one end lowered. Meanwhile the
submarine closed. Several shells from her gun hit the after part of the
_Dunraven_, causing a depth charge to explode and setting her on fire
aft, blowing the officer in charge of the after gun out of his control
station, and wounding severely the seaman stationed at the depth
charges. The situation now was that the submarine was passing from the
port to the starboard quarter, and at any moment the 4-inch magazine and
the remaining depth charges in the after part of the _Dunraven_ might be
expected to explode. The 4-inch gun's crew aft knew the imminence of
this danger, but not a man moved although the deck beneath them was
rapidly becoming red hot; and Captain Campbell was so certain of the
magnificent discipline and gallantry of his crew that he still held on
so that the submarine might come clearly into view on the starboard side
clear of the smoke of the fire aft. In a few minutes the anticipated
explosion occurred. The 4-inch gun and gun's crew were blown into the
air just too soon for the submarine to be in the best position for being
engaged. The explosion itself caused the electrical apparatus to make
the "open fire" signal, whereupon the White Ensign was hoisted and the
only gun bearing commenced firing; but the submarine submerged at once.
Fifteen minutes later a torpedo hit the ship, and Captain Campbell again
ordered "abandon ship" and sent away a second party of men to give the
impression that the ship had now been finally abandoned although her
true character had been revealed. Meanwhile he had made a wireless
signal to other ships to keep away as he still hoped to get the
submarine, which, now keeping submerged, moved round the ship for three
quarters of an hour, during which period the fire gained on the
_Dunraven_ and frequent explosions of ammunition took place.
The submarine then came to the surface right astern where no guns could
bear on her, and recommenced her shellfire on the ship, hitting her
frequently. During this period the officers and men still remaining on
board gave no sign of their presence, Captain Campbell, by his example,
imbuing this remnant of his splendid ship's company with his own
indomitable spirit of endurance. The submarine submerged again soon
afterwards, and as she passed the ship Captain Campbell from his
submerged tube fired a torpedo at her, which just missed. Probably the
range was too short to allow the torpedo to gain its correct depth. She
went right round the ship, and a second torpedo was fired from the other
tube, which again missed. This torpedo was evidently seen from the
submarine, as she submerged at once. The ship was sinking, and it was
obviously of no use to continue the deception, which could only lead to
a useless sacrifice of life; wireless signals for assistance were
therefore made, and the arrival of some destroyers brought the action to
a conclusion. The wounded were transferred to the destroyers and the
ship taken in tow, but she sank whilst in tow forty-eight hours later.
This action was perhaps the finest feat amongst the very many gallant
deeds performed by decoy ships during the war. It displayed to the full
the qualities of grim determination, gallantry, patience and resource,
the splendid training and high standard of discipline, which were
necessary to success in this form of warfare. Lieutenant Charles G.
Bonner, R.N.R., and Petty-Officer Ernest Pitcher, R.N., were awarded the
V.C. for their services in this action, and many medals for conspicuous
gallantry were also given to the splendid ship's company.
Captain Campbell, as will be readily realized, met with great success in
his work, and he was the first to acknowledge how this success was due
to those who worked so magnificently under his command, and he also
realized the magnitude of the work performed by other decoy ships in all
areas, since he knew better than most people the difficulties of
enticing a submarine to her doom.
On September 17, 1917, in position Lat. 49.42 N., Long. 13.18 W., the
decoy ship _Stonecrop_, a small steamer commanded by Commander M.
Blackwood, R.N., armed with one 4-inch, one 6-pounder gun and some
stick-bomb throwers and carrying four torpedo tubes, sighted a
submarine, which opened fire on her at long range, the fire being
returned by the 6-pounder mounted aft. After the shelling had continued
for some time the usual order was given to "abandon ship," and a little
later the periscope of the submarine was sighted some distance away. The
submarine gradually closed, keeping submerged, until within about a
quarter of a mile, when she passed slowly round the ship, and finally
came to the surface at a distance of about 500 yards on the starboard
quarter. She did not close nearer, so the order was given to open fire,
and hitting started after the third round had been fired and continued
until the submarine sank stern first. No survivors were picked up, but
all the indications pointed to the certainty of the destruction of the
submarine.
PATROL GUNBOATS
Mention may here be made of another vessel of a special class designed
in 1917. In the early summer, in consequence of the shortage of
destroyers, of the delays in the production of new ones, and the great
need for more small craft suitable for escorting merchant ships through
the submarine zone, arrangements were made to build a larger and faster
class of trawler which would be suitable for convoy work under
favourable conditions, and which to a certain extent would take the
place of destroyers. Trawlers could be built with much greater rapidity
than destroyers, and trawler builders who could not build destroyers
could be employed for the work, thus supplementing the activities of the
yards which could turn out the bigger craft.
Accordingly a 13-knot trawler was designed, and a large number ordered.
Great delays occurred, however, in their construction, as in that of all
other classes of vessel owing to the pressure of various kinds of war
work and other causes, and only one was delivered during 1917 instead of
the twenty or so which had been promised, whilst I believe that by July,
1918, not more than fourteen had been completed instead of the
anticipated number of forty. I was informed that they proved to be a
most useful type of vessel for the slower convoys, were excellent sea
boats, with a large radius of action, were a great relief to the
destroyers, and even to light cruisers, for convoy work. It is
understood that some fifty were completed by the end of the war.
NET PROTECTION FOR MERCHANT SHIPS
This idea originated in 1915 or 1916 with Captain Edward C. Villiers, of
the _Actaeon_ Torpedo School ship. Experiments were carried out by a
battleship at Rosyth, in the first instance, and later at Scapa. They
were at that time unsuccessful.
At the end of 1916 I gave directions for a reconsideration of the
matter, and fresh trials were made; but early in 1917 there seemed to be
no prospect of success, and the trials were again abandoned. However,
Captain Villiers displayed great confidence in the idea, and he
introduced modifications, with the result that later in the year 1917
directions were given for fresh trials to be undertaken. At the end of
the year success was first obtained, and this was confirmed early in
1918, and the device finally adopted. A curious experience during the
trials was that the vessel carrying them out was actually fired at by a
German submarine, with the result that the net protection saved the ship
from being torpedoed. It is not often that an inventor receives such a
good advertisement.
DEPTH CHARGE THROWERS
The first proposal for this device came from Portsmouth, where the
Commander-in-Chief, Admiral the Hon. Sir Stanley Colville, was
indefatigable in his efforts to combat the submarine; throwers
manufactured by Messrs. Thornycroft, of Southampton, were tried and gave
good results. The arrangement was one by which depth charges could be
projected to a distance of 40 yards from a vessel, and the throwers were
usually fitted one on each quarter so that the charges could be thrown
out on the quarter whilst others were being dropped over the stern, and
the chances of damaging or sinking the submarine attacked were thus
greatly increased.
As soon as the earliest machines had been tried orders were placed for
large numbers and the supplies obtained were as follows:
Deliveries commenced in July, 1917.
By September 1, 30 had been delivered.
By October 1, 97 had been delivered.
By December 1, 238 had been delivered.
COASTAL MOTOR BOATS
At the end of 1916 we possessed 13 fast coastal motor boats, carrying
torpedoes, and having a speed of some 36 knots. They had been built to
carry out certain operations in the Heligoland Bight, working from
Harwich, but the preliminary air reconnaissance which it had been
decided was necessary had not been effected by the end of 1916 owing to
bad weather and the lack of suitable machines.
When winter set in it became impossible, with the type of aircraft then
existing, to carry out the intended reconnaissance, and early in 1917 I
abandoned the idea of the operations for the winter and sent the boats
to the Dover Command for Sir R. Bacon to use from Dunkirk in operations
against enemy vessels operating from Ostend and Zeebrugge. They quickly
proved their value, and it became evident that they would also be useful
for anti-submarine work. A large number were ordered, some for
anti-submarine work and some for certain contemplated operations in
enemy waters, including a night attack on the enemy's light cruisers
known to lie occasionally in the Ems River, an operation that it was
intended to carry out in the spring of 1918. A daylight operation in
this neighbourhood, which was carried out during 1918, did not, from the
published reports, meet with success, the coastal motor boats being
attacked by aircraft, vessels against which they were defenceless. The
new boats were of an improved and larger type than the original 40-feet
boats. Delays occurred in construction owing principally to the
difficulty in obtaining engines by reason of the great demand for
engines for aircraft, and but few of the new boats were delivered during
the year 1917.
MINING OPERATIONS
The policy which was carried out during 1917 in this respect, so far as
the supply of mines admitted, aimed at preventing the exit of submarines
from enemy ports. Incidentally, the fact that we laid large numbers of
mines in the Heligoland Bight rendered necessary such extensive sweeping
operations before any portion of the High Sea Fleet could put to sea as
to be very useful in giving us some indication of any movement that
might be intended. In view of the distance of the Grand Fleet from
German bases and the short time available in which to intercept the High
Sea Fleet if it came out for such a purpose as a raid on our coasts, or
on convoys, the information thus gathered would have proved of great
value.
In planning mining operations in the Heligoland Bight, it was necessary
to take into consideration certain facts. The _first_ was the knowledge
that the Germans themselves had laid minefields in some portions of the
Bight, and it was necessary for our minelayers to give such suspected
areas a wide berth. _Secondly_, it was obvious that we could not lay
minefields in areas very near those which we ourselves had already
mined, since we should run the risk of blowing up our own ships with our
own mines.
Mining operations had necessarily to be carried out at night, and as
there were no navigational aids in the way of lights, etc., in the
Heligoland Bight, the position in which our mines were laid was never
known with _absolute_ accuracy. Consequently an area in which we had
directed mines to be laid, and to which a minelayer had been sent, could
not safely be approached within a distance of some five miles on a
subsequent occasion.
The use in mining operations of the device known as "taut wire" gear,
introduced by Vice-Admiral Sir Henry Oliver, was of great help in
ensuring accuracy in laying minefields and consequently in reducing the
danger distance surrounding our own minefields.
As our mining operations increased in number we were driven farther and
farther out from the German ports for subsequent operations. This
naturally increased the area to be mined as the Heligoland Bight is
bell-mouthed in shape, but it had the advantage of making the operations
of German minesweepers and mine-bumpers more difficult and hazardous as
they had to work farther out, thus giving our light forces better
chances of catching them at work and engaging them. Such actions as that
on November 17, 1917, between our light forces and the German light
cruisers and minesweepers were the result. We did not, of course, lay
mines in either the Danish or Dutch territorial waters, and these waters
consequently afforded an exit for German vessels as our minefields
became most distant from German bases.
Broadly speaking, the policy was to lay mines so thoroughly in the
Heligoland Bight as to force enemy submarines and other vessels to make
their exits along the Danish or Dutch coasts in territorial waters.
At the end of the exit we stationed submarines to signal enemy movements
and to attack enemy vessels. We knew, of course, that the enemy would
sweep other channels for his ships, but as soon as we discovered the
position of these channels, which was not a very difficult matter, more
mines were laid at the end. In order to give neutrals fair warning,
certain areas which included the Heligoland Bight were proclaimed
dangerous. In this respect German and British methods may be contrasted:
We never laid a minefield which could possibly have been dangerous to
neutrals without issuing a warning stating that a certain area (which
included the minefield) was dangerous. The Germans never issued such a
warning unless the proclamation stating that half the Atlantic Ocean,
most of the North Sea, and nine-tenths of the Mediterranean were
dangerous could be considered as such. It was also intended, as mines
became available, to lay more deep minefields in positions near our own
coast in which enemy submarines were known to work; these minefields
would be safe for the passage of surface vessels, but our patrol craft
would force the submarines to dive into them. This system to a certain
extent had already been in use during 1915 and 1916.
Schemes were also being devised by Admiral of the Fleet Sir Arthur
Wilson, who devoted much of his time to mining devices, by which mines
some distance below the surface would be exploded by an enemy submarine
even if navigating on the surface.
Such was the policy. Its execution was difficult.
The first difficulty lay in the fact that we did not possess a
thoroughly satisfactory mine. A percentage only of our mines exploded
when hit by a submarine, and they failed sometimes to take up their
intended depth when laid, betraying their presence by appearing on the
surface.
Energetic measures were adopted to overcome this latter defect, but it
took time and but few mines were available for laying in the early
months of 1917.
The result of our minelaying efforts is shown in the following table:
Mines laid Deep mines laid
Year. in the Heligoland off our own coasts
Bight. to catch submarines.
1915 4,498 983
1916 1,679 2,573
First quarter of 1917 4,865 )
Second quarter of 1917 6,386 ) 3,843
Third quarter of 1917 3,510 )
In the Straits of Dover, Thames Estuary and off the Belgian coast we
laid 2,664 mines in 1914, 6,337 in 1915, 9,685 in 1916, and 4,669 in the
first three quarters of 1917.
These last mines were laid as fast as the alterations, made with a view
to increasing their efficiency, could be carried out.
During the early part of the year 1917 the new pattern of mine, known as
the "H" Type, evolved in 1916, had been tried, and although not
perfectly satisfactory at the first trials, the success was sufficient
to warrant the placing of orders for 100,000 mines and in making
arrangements for the quickest possible manufacture. This was done by the
Director of Torpedoes and Mines, Rear-Admiral the Hon. Edward
Fitzherbert, under the direction of the then Fourth Sea Lord,
Rear-Admiral Lionel Halsey.
Deliveries commenced in the summer of 1917, but by the end of September
only a little over 1,500 were ready for laying. Some 500 of these were
laid in September in the Heligoland Bight and were immediately
successful against enemy submarines. More were laid in the Bight during
October, November and December, and the remainder, as they were
produced, were prepared for laying in the new minefield in the Straits
of Dover. _In the fourth quarter of the year a total of 10,389 mines was
laid in the Heligoland Bight and in the Straits of Dover._
During this last quarter delivery of "H" pattern mines was as follows:
In October 2,350, November 5,300, December 4,800; total 12,450. So that
it will be seen that the mines were laid as fast as delivery was made.
The great increase in projected minelaying operations during the year
1917 made it necessary also to add considerably to the number of
minelaying vessels.
In January, 1917, the only vessels equipped for this service were four
merchant ships and the Flotilla Leader _Abdiel_, with a total minelaying
capacity of some 1,200 mines per trip. It was not advisable to carry out
minelaying operations in enemy waters during the period near full moon
owing to the liability of the minelayers being seen by patrol craft.
Under such conditions the position of the minefield would be known to
the enemy. As the operation of placing the mines on board occupied
several days, it was not passible to depend on an average of more than
three operations per ship per month from the larger minelayers.
Consequently, with the intended policy in view, it was obvious that more
minelayers must be provided.
It was inadvisable to use merchant ships, since every vessel was
urgently required for trade or transport purposes, and the alternative
was to fit men-of-war for minelaying. The only old vessels of this type
suitable for mining in enemy waters were ships of the "Ariadne" class,
and although their machinery was not too reliable, two of these vessels
that were seaworthy were converted to minelayers. In addition a number
of the older light cruisers were fitted with portable rails on which
mines could be carried when minelaying operations were contemplated, in
place of a portion of the armament which could be removed; a flotilla of
destroyers, with some further flotilla leaders, were also fitted out as
minelayers, and several additional submarines were fitted for this
purpose.
For a projected special scheme of minelaying in enemy waters a number of
lighters were ordered, and some of the motor launches and coastal motor
boats were fitted out and utilized for mining operations on the Belgian
coast towards the end of 1917.
By the end of that year 12 light cruisers, 12 destroyers and flotilla
leaders and 5 submarines had been fitted for minelaying. Two old
cruisers had been added to the minelaying fleet and several other
vessels were in hand for the same purpose. The detailed plans of the
arrangements were prepared and the work of fitting out minelayers
carried out under the supervision of Admiral R.N. Ommanney, C.B., whose
services in this matter were of great value. The rapidity with which
ships were added to the minelaying fleet was largely due to his efforts.
On the entry of the United States of America into the war a further
development of mining policy became feasible. The immense manufacturing
resources of the United States rendered a large production of mines an
easy matter, with the result that as soon as the United States Navy
produced a reliable type of mine the idea of placing a mine barrage
across the northern part of the North Sea which had been previously
discussed became a matter of practical politics. With this end in view a
still further addition to the minelaying fleet became necessary, and
since the mining would be carried out at leisure in this case and speed
was no great necessity for the minelayer owing to the distance of the
minefields from enemy waters, an old battleship was put in hand for
conversion.
With the enormous increase in the number of mines on order the problem
of storage became of importance, including as it did the storage of the
very large number, some 120,000, required for the northern barrage. The
Third Sea Lord, Admiral Lionel Halsey, took this matter in hand with
characteristic energy, and in conjunction with United States naval
officers made all the necessary arrangements.
The United States mines were stored in the vicinity of Invergordon, and
the British mines intended for use in the northern barrage were located
at Grangemouth, near Leith, where Rear-Admiral Clinton Baker was in
charge, as well as in other places, whilst those for use in the
Heligoland Bight and Channel waters were stored at Immingham and other
southern depots.
The laying of the North Sea mine barrage was not accomplished without
very considerable delay, and many difficulties were encountered. It was
originally anticipated that the barrage would be completed in the spring
of 1918, but owing to various defects in both British and United States
mines which made themselves apparent when the operations commenced, due
partly to the great depth of water as well as to other causes, a delay
of several months took place; and, even when near completion, the
barrage was not so effective as many had hoped in spite of the great
expenditure of labour and material involved. I have not the figures of
the number of submarines that the barrage is thought to have accounted
for, but it was known to be disappointing.
FLARES
In the late summer of 1917 _flares_ were experimented with; they were
intended to be used from kite balloons with the object of sighting
submarines when on the surface at night. Previously searchlights in
destroyers had been used for this purpose. The flares were not much
used, however, from kite balloons owing to lack of opportunity, but
trials which were carried out with flares from patrol craft, such as
trawlers and drifters, demonstrated that they would be of value from
these vessels, and when the Folkestone-Grisnez minefield was laid in
November and December, 1917, it was apparent that the flares would be of
use in forcing submarines to dive at night into the minefield to escape
detection on the surface and attack by gunfire.
Manufacture on a large scale was therefore commenced, and during 1918
the flares were in constant use across the Straits of Dover.
ELECTRICAL SUBMARINE DETECTOR
The existence of this very valuable device was due to the work of
certain distinguished scientists, and experiments were carried out
during 1917. It was brought to perfection in the late autumn, and orders
were given to fit it in certain localities. Some difficulty was
experienced in obtaining the necessary material, but the work was well
in hand by the end of the year, and quickly proved its value.
SUBMARINE AGAINST SUBMARINE
Prior to the year 1917 the only areas in which our own submarines
operated against enemy vessels of the same type was in the North Sea, or
occasionally in the vicinity of the Hebrides. Grand Fleet submarines
were used in the northern areas during 1916, and Harwich submarines
operated farther south, but the number of underwater craft available was
insufficient for any extended method of attack. Early in 1917, when our
mercantile losses were very heavy, some submarines were withdrawn from
the Harwich and Humber districts and formed into a flotilla off the
coast of Ireland for this form of operation. Some risk had to be
accepted in thus reducing our submarine strength in southern waters. At
the same time some Grand Fleet submarines were organized into a watching
patrol in the area off the Shetland Islands, through which enemy
submarines were expected to pass. The watch off the Horn Reef and in the
Heligoland Bight, which had previously been in force, was also
maintained.
A little later the submarine flotilla off the Irish coast was
strengthened, and a regular patrol instituted near the North Channel
between Ireland and Scotland. The next step was the withdrawal of some
"C" Class submarines from coastal work on our east coast to work in the
area between England and Holland near the North Hinder Lightship, a
locality much frequented by enemy submarines on passage. Still later
some submarines were attached to the Portsmouth Command, where, working
under Sir Stanley Colville, they had some striking successes; others
went to the Dover Command. The latter were fitted with occulting lights
on top of the conning-tower, and were moored at night to buoys in the
Dover Net Barrage, in places where enemy submarines were likely to pass,
in order that they might have a chance of torpedoing them. A division of
submarines was also sent to Gibraltar, to operate against enemy cruiser
submarines working in that vicinity or near the Canaries. Successes
against enemy submarines were also obtained in the latter locality.
Finally, the arrival of some United States submarines enabled the areas
in which this form of attack was in force to be still further extended,
after the American personnel had been trained to this form of warfare.
There was a great increase in the number of enemy submarines sunk by
this method of attack during 1917 as compared with previous years; the
number of vessels sunk does not, however, convey a complete appreciation
of the effect of this form of anti-submarine warfare. The great value of
it lay in the feeling of insecurity that it bred in the minds of the
enemy submarine commanders. The moral effect of the constant
apprehension that one is being "stalked" is considerable. Indeed, the
combination of our aircraft and our submarine patrols led to our vessels
reporting, regretfully, that it was very seldom that German submarines
were found on the surface in daylight, and towards the end of 1917 quite
a large proportion of the attacks on merchant ships took place at night.
The work for our own vessels was very arduous indeed. It was only on
rare occasions that it was possible to bring off a successful attack on
a submarine that had been sighted, the low underwater speed of
submarines making it difficult to get into position when the enemy was
only sighted at short range, which was naturally usually the case.
In order to obviate this difficulty directions were given in 1917 to
design a special type of submarine for this form of warfare, and I
believe that the first vessel was completed by the autumn of 1918.
This account of the development of anti-submarine measures during 1917
would not be complete without mention of the work of the Trade Division
of the Staff, of which Captain Richard Webb, C.B., was the Director
until September.
This Division was either partly or wholly responsible for:
(1) The great increase in the rapidity of placing the armaments on board
merchant ships.
(2) The establishment of schools of instruction for captains and
officers of the Mercantile Marine.
This training scheme was begun at Chatham Barracks in February, 1917, by
Commander E.L.B. Lockyer, acting under Captain Webb, and later was
extended to Portsmouth, Cardiff and Greenock. Its success was so marked,
and its benefit in assisting officers to handle their ships in the
manner best calculated to save them from submarine attack so great, that
the Admiralty was continually being pressed by shipowners and by the
officers of the Mercantile Marine to extend the instruction to more and
more ports. This was done so far as possible, our principal difficulty
being to provide officers capable of giving the instruction required.
(3) The provision of wireless plant and operators to the Mercantile
Marine. This was another matter taken up with energy during 1917, and
with excellent results.
(4) The drilling of guns crews for the merchant ships. Men were invited
to go through a course of drill, and large numbers responded and were
instructed at the Royal Naval Depot at the Crystal Palace.
All these matters were additional to the important work upon which the
Trade Division was constantly employed, which included all blockade
questions, the routeing of merchant ships, examination of ships, etc.
In addition to the instructional anti-submarine course for masters and
officers, gunnery courses for cadets and apprentices were started at
Portsmouth, Chatham and Devonport. A system of visits to ships by
officer instructors for the purpose of affording instruction and for
inspection, as well as for the purpose of lecturing, was instituted, and
arrangements were made for giving instruction in signalling. Some idea
of the work carried out will be gathered from the following figures
showing the instructional work carried out during the year 1917:
Masters 1,929
Officers 2,149
Number of cadets and apprentices passed through
the gunnery course 543
Number of merchant seamen trained in gunnery at
the Crystal Palace 3,964
Number of ships visited by officer instructors 6,927
Numbers attending these lectures:
Masters 1,361
Officers 5,921
Number of officers and men instructed in signalling 10,487
The keenness shown by officers and men of the merchant service
contributed in a marked degree to the success of the courses instituted;
just one example may be given. I visited the Royal Naval Depot at the
Crystal Palace early in 1918, and amongst other most interesting scenes
witnessed a large number of men of the merchant service at gun drill. I
questioned several of them as to their experiences, and many of the men
had had their ships torpedoed under them three, four or five times.
Amongst the gun crews was a steward who had been through this experience
four times. On my asking why he, as a steward, should be going through
the gunnery course, he replied that he hoped that by so doing he might
stand a chance of getting his own back by assisting to sink a submarine.
The knowledge which I possessed of the measures introduced during the
year 1917 to combat the German submarine warfare, and the continual
increase in the efficiency of the anti-submarine work which I knew would
result from increased production of anti-submarine vessels and weapons,
led me in February, 1918, to state that in my opinion the submarine
menace would be "held" by the autumn of the year 1918. The remark, which
was made at what I understood to be a private gathering, was given very
wide publicity, and was criticized at the time, but it was fulfilled, as
the figures will indicate.