The introduction of the locomotive torpedo triggered Navies to equip their ships with machine-guns capable of sinking (or severely damaging) attacking torpedo-boats. This site looks at how these machine-guns worked, principally the Nordenfelt and Hotchkiss guns, as well as smaller calibre hand-operated machine guns from Gatling, Gardner and the Belgian and French Mitrailleuse. Follow the link to Automatic Machine Guns for animations of Maxim guns.
All the machine-guns discussed here were hand-powered - the gunner had to turn a handle or move a lever to load and fire. The smaller calibre machine guns, Gatling, Gardner and Mitrailleuse were made obsolete by the introduction into service of the self-loading machine-gun by Hiram Maxim in 1889. The large calibre machine guns of Nordenfelt and Hotchkiss were replaced by single-barrelled quick-firing guns in the 1890s, since larger torpedo-boats and the increased range of torpedoes required a larger calibre than could be sensibly provided by the multi-barrelled machine-guns - they would be too heavy.
A limited amount of history is included, and where possible links are provided to sites that provide a greater coverage.
Need for Machine Guns in Naval Service
In the period 1880 - 1895, tactical thought was that battles between capital ships would be fought at short range – very thick armour could not be penetrated except by a large calibre gun at short range and it was very difficult to hit a moving enemy ship at the longer ranges due to own ship’s movements and lack of accurate range-finders. Indeed one school of thought maintained that since the armour could not be penetrated, ramming was the best way of sinking an enemy. Even if you could not manage to ram, boarding remained an option, and there was great value in having rifle-calibre machine-guns mounted in the fighting tops to sweep the enemy’s decks of borders and kill the guns crews.
The following text has been taken from Nordenfelt's Book, 1884. [N3]. I feel it gives a fair explanation of the threat from torpedo boats of the time, and how best to deal with it.
"In future fleet actions ample opportunities will occur for the employment of machine guns under the most favourable conditions, that is to say at short ranges. Such will be afforded when approaching and passing through the enemy’s lines during the first charge of the opposing fleets, or during an attempt to ram, when one disabled ship may drift on to and fall aboard of another vessel, etc.. The experience gained of late, apropos the use of the ram, tends to show that the only chance afforded the crew of a vessel that has been successfully rammed, to escape, is to endeavour by every available means to secure herself by grappling the ship that has rammed her, and then board that vessel. Also it may very possibly happen in an unsuccessful attempt to ram that the two vessels might become locked together for a time. Under all these circumstances the full power, that is ‘the number of shots that can be poured forth in a short space of time’, of machine guns will be effectively developed; and whereas machine guns of some kind or other are generally adopted in all navies, this will resolve itself into a duel between rival machine guns of the vessels engaged, when the most effective weapons, or the best served and manipulated ones will silence the fire of the adversary’s machine guns."[N3]
However, in 1866, Robert Whitehead developed his locomotive torpedo, and within 10 years torpedoes with ranges of up to 600 yards were part of most Navys' weaponry. A torpedo warhead exploding below the armoured belt could easily damage or sink a battleship. The French Navy quickly saw the advantage of large numbers of small, fast and relatively expendable torpedo armed boats for attacking major warships.
"Torpedo boat attacks will mainly be directed against fleet ships, either during a general action or when forming part of a blockading force cruising off an enemy’s port or coasts, etc.., and the torpedo boats will be armed with locomotive or spar torpedoes against which ships are sometimes, comparatively speaking, defenceless. Therefore it is imperatively necessary to provide all vessels of war, and especially fleet ships, with some weapon offering the best chance of disabling the torpedo boat before it can discharge or use its torpedo. The other work delegated to machine guns, such as attack of unarmoured ships, sweeping an enemy’s decks etc.. though undoubtedly of vast importance, yet cannot be compared with this special duty of protecting the costly and comparatively rare fleet ship against torpedo boat attacks.
The principal features of an attacking torpedo craft may be said to be its high rate of speed and the small target presented.
The speed of such craft may be considered as 20 knots per hour, which is a very high average for actual service. At this rate a torpedo boat will traverse:
33 feet in 1 second
300 yards in 26 seconds
500 yards in 44 seconds
It has been roughly demonstrated that a100-foot Thornycroft torpedo boat, with a displacement of some 35 tons, and proceeding at the rate of 20 knots per hour will, on the engines being stopped, come to a standstill in some 35 seconds, and during that time cover a distance of 200 yards. Turning the engine full speed astern from full speed ahead, the boat will be stopped in half her length and be moving astern in a few seconds.
It is considered feasible to discharge the Whitehead from a boat proceeding at its greatest speed with a fair chance of hitting a fleet ship at a distance of from 300 to 400 yards, but would require considerable skill in setting the rudder apparatus of the torpedo, and therefore under the difficulties attending a night attack, or in a day attack under machine gun fire, would be rarely attempted. On actual service, the speed of the boat would be reduced to some 10 knots, and then its torpedo would be discharged, either right ahead, or in such a manner that on striking the water, it would be deflected towards the vessel aimed at in a line direct from the beam of the torpedo boat.
The time chosen for a torpedo boat attack would be usually during the night, or in thick weather. Its specific object, if armed with the Whitehead torpedo, would be to get within 400 yards of the ship attacked, and there discharge her submarine weapon. Only under exceptional circumstances would she attempt to fire the same from a greater distance. Possibly the torpedo boat might be brought even closer, say within 200 yards before discharging her torpedo, by adopting the tactics of dashing up from ahead or astern of the vessel and firing her weapon as she gets abreast of the ship and is turning her head away from her.
Under ordinary circumstances, when the attack occurs at night or in thick weather, there is little probability of a torpedo boat being discovered at more than 600 yards’ distance. She would not afford the defenders more than some 20 seconds for the purpose of destroying her, until she has reached the proper distance for discharging her torpedo.
In the case of an attack by a boat armed with a spar torpedo, she would endeavour to creep as near as possible to the ship undiscovered and then dash in at full speed, only reversing the engines at the instant of striking the vessel with her torpedo. In this case the time afforded for the defense would be some 40 seconds in which to frustrate the attack, allowing the boat to be observed at a distance of some 500 yards from the ship.
In summary, it may be assumed that the time offered the machine guns of the defense to repel a torpedo boat attack would, when the Whitehead weapon is employed, be at least 20 seconds and at an average range of 400 yards. If a spar torpedo be used, the time would be increased to at least 35 seconds and at a range varying from 500 yards to 50 yards. One most important point must be borne in mind when considering how best to prevent the successful issue of an attack by a torpedo boat, viz..., ‘that after a Whitehead or other locomotive torpedo has been started on its deadly errand, or a spar torpedo has been brought to within 50 yards from the ship, it will then be probably too late to save the ship by destruction of the torpedo boat’.
As regards the fate of the boat making such an attack, there seems little probability of her escaping destruction, even if she succeed in discharging her torpedo, for the defense would have 20 seconds from the time the boat is discovered before the torpedo is discharged, and also the 20 to 30 seconds necessary for the torpedo to travel the space between the boat and the ship. For the purpose of the destruction of the boat that is in all some 40 to 50 seconds with the boat at a range varying from 300 yards to 600 yards.
From the foregoing it may be deduced that for the repelling of a torpedo boat attack the machine guns of the defense should be capable of achieving one or other of the following results:
a. the complete disablement of the torpedo boat itself
b. the disablement of the boat’s torpedoes.
Disablement of the Boat
In the event of the attack being made with a locomotive torpedo this could only be considered as satisfactorily accomplished by seriously damaging the torpedo boat’s machinery and boiler. It the boiler be struck, the probability is that it will be burst and destroy the boat, or if it be completely pierced it will cause such an outrush of steam as to prevent any possibility of the attack being continued. By effecting damage to the machinery in such a manner as to cause the boat to stop or slow down for even a few second under the fire of the machine guns, a further opportunity will be afforded to those weapons of the defense to riddle the boat and effect the penetration of its boiler. It must be remembered that a torpedo boat owes its chance of success to the fact of its great speed, and therefore anything tending to delay the boat must be a serious matter.
Though the torpedo boat may be penetrated sufficiently to cause her to ultimately sink, this could not be done so rapidly as to prevent the torpedo being discharged, and therefore as previously stated, more decided damage must be effected to frustrate entirely such an attack, especially as the hits would generally be above the waterline.
Disablement of the Boat’s Torpedoes
This could be effected by a variety of causes, such as the cutting of the wires or perforation of the charge of the spar torpedo, damaging the ejection tubes, frames or gear, penetrating the engines, air chambers or magazine (containing gun cotton or dynamite) of the Whitehead torpedo. Though penetration of the charge of the torpedo might not cause its explosion, unless in the case of the Whitehead torpedo the firing arrangement is struck, yet the penetration of the hull of the Whitehead in any part would seriously interfere with its efficiency, if not completely disabling it; while in the case of a spar torpedo the electric firing arrangement within it would most probably be rendered useless." [N3]