The Crisis of the Naval War online

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.


CHAPTER IV

THE INTRODUCTION OF THE CONVOY SYSTEM


The question of the introduction of convoys for the protection of
merchant ships was under consideration at various times during the war.
The system had been employed during the old wars and had proved its
value in the case of attack by vessels on the surface, and it was
natural that thoughts should be directed towards its reintroduction when
the submarine campaign developed. There is one inherent disadvantage in
this system which cannot be overcome, although it can be mitigated by
careful organization, viz. the delay involved. Delay means, of course, a
loss of carrying-power, and when tonnage is already short any proposal
which must reduce its efficiency has to be very carefully examined. The
delay of the convoy system is due to two causes, (a) because the speed
of the convoy must necessarily be fixed by the speed of the slowest
ship, and (b) the fact that the arrival of a large number of ships at
one time may cause congestion and consequent delay at the port of
unloading. However, if additional safety is given there is compensation
for this delay when the risk is great. One danger of a convoy system
under modern conditions should be mentioned, viz. the increased risk
from attack by mines. If ships are sailing singly a minefield will in
all probability sink only one vessel - the first ship entering it. The
fate of that ship reveals the presence of the field, and with adequate
organization it is improbable that other vessels will be sunk in the
same field. In the case of a convoy encountering a minefield, as in the
case of a fleet, several ships may be sunk practically simultaneously.

During the year 1916, whilst I was still in command of the Grand Fleet,
suggestions as to convoys had been forwarded to the Admiralty for the
better protection of the ocean trade against attack by surface vessels;
but it was pointed out to me that the number of cruisers available for
escort work was entirely insufficient, and that, consequently, the
suggestions could not be adopted. This objection was one that could only
be overcome by removing some of the faster merchant ships from the trade
routes and arming them. To this course there was the objection that we
were already - that is before the intensive campaign began - very short of
shipping.

Shortly after my taking up the post of First Sea Lord at the Admiralty,
at the end of 1916, the question was discussed once more. At that time
the danger of attack by enemy raiders on shipping in the North Atlantic
was small; the protection needed was against attack by submarines, and
the dangerous area commenced some 300-400 miles from the British
Islands. It was known that unrestricted submarine warfare was about to
commence, and that this would mean that shipping would usually be
subjected to torpedo attack from submarines when in a submerged
condition. Against this form of attack the gun armament of cruisers or
armed merchant ships was practically useless, and, however powerfully
armed, ships of this type were themselves in peril of being torpedoed.
Small vessels of shallow draught, possessing high speed, offered the
only practicable form of protection. Shallow draught was necessary in
order that the protecting vessels should themselves be comparatively
immune from successful torpedo fire, and speed was essential for
offensive operations against the submarines.

Convoy sailing was, as has been stated, the recognized method of trade
protection in the old wars, and this was a strong argument in favour of
its adoption in the late war. It should, however, be clearly understood
that the conditions had entirely changed. Convoy sailing for the
protection of merchant ships against torpedo attack by submarines was
quite a different matter from such a system as a preventive against
attack by surface vessels and involved far greater difficulties. In the
days of sailing ships especially, accurate station keeping was not very
necessary, and the ships comprising the convoy sailed in loose order and
covered a considerable area of water. On a strange vessel, also a
sailing vessel, being sighted, the protecting frigate or frigates would
proceed to investigate her character, whilst the ships composing the
convoy closed in towards one another or steered a course that would take
them out of danger.

In the circumstances with which we were dealing in 1917 the requirements
were quite otherwise. It was essential for the protection of the convoy
that the ships should keep close and accurate station and should be able
to manoeuvre by signal. Close station was enjoined by the necessity of
reducing the area covered by the convoy; accurate station was required
to ensure safety from collision and freedom of manoeuvre. It will be
realized that a convoy comprising twenty to thirty vessels occupies
considerable space, even when steaming in the usual formation of four,
five or six columns. Since the number of destroyers or sloops that could
be provided for screening the convoy from torpedo attack by submarines
was bound to be very limited under any conditions, it was essential that
the columns of ships should be as short as possible; in other words,
that the ships should follow one another at close intervals, so that the
destroyers on each side of the convoy should be able as far as possible
to guard it from attack by submarines working from the flank, and that
they should be able with great rapidity to counter-attack a submarine
with depth charges should a periscope be sighted for a brief moment
above the surface, or the track of a torpedo be seen. In fact, it was
necessary, if the protection of a convoy was to be real protection, that
the ships composing the convoy should be handled in a manner that
approached the handling of battleships in a squadron. The diagram on p.
107 shows an ideal convoy with six destroyers protecting it, disposed in
the manner ordered at the start of the convoy system.

[Illustration on page 107, with caption "Diagram illustrating a convoy
of 25 Merchant Ships, with an escort of 6 Destroyers zigzagging at high
speed for protection. The convoy shown in close order and on its normal
course."]

[Illustration on page 108 shows, according to its caption, "Typical
convoy and escort of 10 Trawlers in the early days of convoy."]

How far this ideal was attainable was a matter of doubt. Prior to 1917
our experience of merchant ships sailing in company had been confined to
troop transports. These vessels were well officered and well manned,
carried experienced engine-room staffs, were capable of attaining
moderate speeds, and were generally not comparable to ordinary cargo
vessels, many of which were of very slow speed, and possessed a large
proportion of officers and men of limited sea experience, owing to the
very considerable personnel of the Mercantile Marine which had joined
the Royal Naval Reserve and was serving in the Fleet or in patrol craft.
Moreover, even the troop transports had not crossed the submarine zone
in company, but had been escorted independently; and many naval officers
who had been in charge of convoys, when questioned, were not convinced
that sailing in convoy under the conditions mentioned above was a
feasible proposition, nor, moreover, were the masters of the transports.

In February, 1917, in order to investigate this aspect of the question,
a conference took place between the Naval Staff and the masters of cargo
steamers which were lying in the London docks. The masters were asked
their opinion as to how far their ships could be depended on to keep
station in a convoy of 12 to 20 vessels. They expressed a unanimous
opinion that it was not practicable to keep station under the conditions
mentioned, the difficulty being due to two causes: (1) the inexperience
of their deck officers owing to so many of them having been taken for
the Royal Naval Reserve, and (2) the inexperience of their engineers,
combined with the impossibility of obtaining delicate adjustments of
speed by reason of the absence of suitable engine-room telegraphs and
the poor quality of much of the coal used. When pressed as to the
greatest number of ships that could be expected to manoeuvre together in
safety, the masters of these cargo steamers, all experienced seamen,
gave it as their opinion that two or possibly three was the maximum
number. The opinions thus expressed were confirmed later by other
masters of merchant ships who were consulted on the subject. It is to
the eternal credit of the British Merchant Marine, which rendered
service of absolutely inestimable value to the Empire throughout the
war, that when put to the test by the adoption of the convoy system,
officers and men proved that they could achieve far more than they
themselves had considered possible. At the same time it should be
recognized how severe a strain was imposed on officers, particularly the
masters, of vessels sailing in convoy.

The matter was kept constantly under review. In February, 1917, the
Germans commenced unrestricted submarine warfare against merchant ships
of all nationalities, and as a consequence our shipping losses, as well
as those of Allied and neutral countries, began to mount steadily each
succeeding month. The effect of this new phase of submarine warfare is
best illustrated by a few figures.

During the last four months of 1916 the gross tonnage lost by _submarine
attack_ alone gave the following monthly average: British, 121,500;
Allies, 59,500; neutrals, 87,500; total, 268,500.

In the first four months of 1917 the figures became, in round numbers:

British. Allies. Neutrals. Total.

January 104,000 62,000 116,000 282,000
February 256,000 77,000 131,000 464,000
March 283,000 74,000 149,000 506,000
April 513,000 133,000 185,000 831,000

(The United States entered the war on April 6, 1917.)

NOTE. - In neither case is the loss of fishing craft included.

It will be realized that, since the losses towards the end of 1916 were
such as to give just cause for considerable anxiety, the later figures
made it clear that some method of counteracting the submarines must be
found and found quickly if the Allied cause was to be saved from
disaster.

None of the anti-submarine measures that had been under consideration or
trial since the formation of the Anti-Submarine Division of the Naval
Staff in December, 1916, could _by any possibility_ mature for some
months, since time was necessary for the production of vessels and more
or less complicated matériel, and in these circumstances the only step
that could be taken was that of giving a trial to the convoy system for
the ocean trade, although the time was by no means yet ripe for
effective use of the system, by reason of the shortage of destroyers,
sloops and cruisers, which was still most acute, although the situation
was improving slowly month by month as new vessels were completed.

Prior to this date we had already had some experience of convoys as a
protection against submarine attack. The coal trade of France had been
brought under convoy in March, 1917. The trade between Scandinavia and
North Sea ports was also organized in convoys in April of the same year,
this trade having since December, 1916, been carried out on a system of
"protected sailings." It is true that these convoys were always very
much scattered, particularly the Scandinavian convoy, which was composed
largely of neutral vessels and therefore presented exceptional
difficulties in the matter of organization and handling. The number of
destroyers which could be spared for screening the convoys was also very
small. The protection afforded was therefore more apparent than real,
but even so the results had been very good in reducing the losses by
submarine attack. The protection of the vessels employed in the French
coal trade was entrusted very largely to trawlers, as the ships
composing the convoy were mostly slow, so that in this case more
screening vessels were available, although they were not so efficient,
being themselves of slow speed.

For the introduction of a system of convoy which would protect merchant
ships as far as their port of discharge in the United Kingdom, there
were two requirements: (a) A sufficient number of convoying cruisers or
armed merchant ships, whose role would be that of bringing the ships
comprising the convoy to some selected rendezvous outside the zone of
submarine activity, where it would be met by the flotilla of small
vessels which would protect the convoy through the submarine area. It
was essential that the ships of the convoy should arrive at this
rendezvous as an organized unit, well practised in station-keeping by
day, and at night, with the ships darkened, and that the vessels should
be capable also of zigzagging together and of carrying out such
necessary movements as alterations of course, etc.; otherwise the convoy
could not be safely escorted through the danger area. (b) The other
essential was the presence of the escorting flotilla in sufficient
strength.

It has been mentioned that there was an insufficient number of vessels
available for use as convoying cruisers. It was estimated that about
fifty cruisers or armed merchant ships would be required for this
service if the homeward-bound trade to the British Isles alone was
considered. An additional twelve vessels would be necessary to deal with
the outward-bound trade. At the time only eighteen vessels were
available, and these could only be obtained by denuding the North
Atlantic entirely of cruisers.

The situation in regard to destroyers or other fast vessels presented