THE PRELIMINARY FOR ATTACK

Dominion, Volume 11, Issue 227, 13 June 1918, Page 7

THE PRELIMINARY FOR ATTACK

ORGANISING THE ARTILLERY PREPARATION

ELABORATE SCHEME RE.

QUIRED

Until the affair of Cambrai, on Xovomber 20, 1917, it was considered.an established fact of trench warfare that any infantry attack upon, a largo scalo must , .1)0 preceded by a preliminary bombardment of hoavy artillery. Although the success achieved on this particular occasion justified the omission of this bombardment, it is doubtful whether it will bo practicable to repeat theso surprise tactics, and it is safe to assumo that the preliminary bombardment will remain an essential ]«rt of the preparation for ; attack. As soon as an attack upon any given sector is determined upon, it must be decided how far destruction of the hostile trenches by artillery is necessary. This sottles the number of guns that will be required to support tho attack. Thero will he a certain number of batteries in tho neighbourhood already, but these will require reinforcement by batteries drawn from elsewhere, either from reserve, or from other parts of the line. All preparations, too, must be made for the reception of these batteries. Positions must bo found for tlieni, from which they can fire over the required sector, and, ii' possible, theso positions must bo sot ready before the batteries arrive. The times of the batteries' arrivals must be carefully regulated. They must not be concentrated too soon, in ease warning is thus given to the enemy of the .impending attack. Nor must they bo rushed in at tho last moment, or they -will have no opportunity of learning the country, and of carrying out this necessary registration. They will move into position by night, and tho routes by which [hey travel must be carefully worked out, so that they do not clash, and that other traffic is not blocked. Ammunition Supplies. Besides the allotment of positions, all arrangements must be made beforehand tor ammunition supply. The various tractors and lorries of tho batteries must have a parking ground assigned to them, which must be conveniently situated with regard to" the railhead from which ammunition is .to be drawn as will go to the battery position. The routes that the lorries aru Ui lollow in their journeys Irom railhead to battery must be worked out in Much a wny as lo provide vapid, supply with the least possible obstruction to the roads, which will be overtaxed already by the concentration of troops and by tho suppiy columns that such a concentration necessitates. ]f time and circumstances permit light railways can be constructed lo reliero the roads, and gnus can be seen from these into the battery positions. Such construction will nearly always be necessary if it is proposed to employ guns upon railway mountings. Mobile workshops will bo required to effect repairs to guns put out of action by constant firing or by hostile shell-fire. ■ theso must bo established at centres convenient to all the batteries, and arrange- ; men fa must be ■ made for a system of rapid removal of guns to and from these i workshops. . The question, of supplying rations and water to the personuel of the batteries must bo considered, and in this connection the position of tiieir billets, dug-outs,, or bivouacs must be thought out. It may often be convenient to havo theso some distance from the gums in order to facilitate supply. As soon as the batteries arrive they must be informed of the sector over which they will bo required to lire, and allotted observation posts if such already exist. .Thev wih then carry out registration upon certain paints "in order to correct their line and to ensure the accuracy of subsequent map shooting. It is essential that this registration should be carried out; more or lew deliberately. If several batteries register on the same day, it will be obvious to tho enemy that a quantity of guns has been concentrated in front of him, and ho will naturally infer that an attack 's about to lake place. For tho same reasons, the utmost precautions must be taken at this stage against the discovery of the batteries by hostile aircraft. The Area for Destruction. The next step is to determine cxactly what the preliminary bombardment is to eltect, leaving out sueh operations as wire-cutting and counter-battery work, the typical effect required is the destruc- : tion of certain trenches and strong , points. These trenches and strong points must be divided up between the , butteries, cither by providing each with a list of targets or by allotting a certain area ol ground, to each battery, which yvill engage all targets in that area. It ■ is known by experience approximately ; how many hits by a given size of shell i will destroy a certain tyne of target. ' But, in tho most favourable circumstances, only a certain percentago of I the rounds fired at tho target will be 1 hits, owing to tho variations in trajec- ; toiy which. are a definite condition of 1 ballistics. It is, however, possible .to calculato what this percentage will be by tho application of the theory of prob- '• ability to tho particular factors in each * caso. For instance, supposo it is known e by experience that five hits from a, cer- 1 tain size of howitzer in every twenty f yards of a particular typo of trench will

destroy it Riifliciontly (o rcndor it useless as a dofewsivo position, and that each battery is allotted about 100 vards ot tins trench. Each battery will'then require lo obtain 25 hits. JJv reference to certain data, and by the application "I the l iitory of probability to the case, it in calculated that the batteries may expect to land, say, 10 per cent, of llio rounds they tiro into (lie trench. Uy proceeding to consider in a similar way each portion of the work allotted to the batteries it is possiblo to discover, the approximate number of rounds that will be required during the preliminary bombardment, and from this ugain the fim.-) that the bomburdment will lake. ■V programme can now bo drawn up, <leliin iik the targets that are to bo engaged and the time and number of rounds to be expanded in engaging them. The details of ammunition supply can also be worked out, tsuch as the number of rounds to be accumulated at each battery position and at dumps in rear before the bombardment commences, aud I the number of rounds to bo supplied from rail head during the nights between the commencement of the bombardment and the delivery of the attack. All these arrangements must bo sufficiently flexible to allow of instant modification of details in case tho unexpected happens, as on practice it generally does. Further tamels may bo discovered; they must be destroyed before the attack; tho flatteries engaged upon counter-battery work may become available tor bombardment, or the foijmer may require assistance from the latter. Weather conditions mav necessitate alterations in the nrogramme, or even the postponement of the attack. Therefore, whilst organisation must ho as perfect as possible, it must not be so rigid as to break down under the strain of sudden modification.

The Question of tlie observation of Ihe I shooting is the most pressing ono to the batteries themselves. Tho more accurate the observation posiblo, tho more thoroughly will tho diutruction lie earned out. The ideal is to find some observation post or posts from which the targets can lie directly observed. Ground observation is tlie most accurate beyond >i doubt, but it is not always that the weather or tho configuration of tho ground admit of it. It' a ridge exists, however 6light, from which tlie enemy's defensive 'systpm ran be Been, thero is usually no difficulty. Failing this, recourse must be had to observation by kite balloons or aeroplanes. Both have their disadvantages. Tho kite balloon must be kept back almost out of range of the enemy's guns, and therefore requires considerable clarity of atmosphere to observe at the range at which it is forced to work. Further, the number of balloons that can see a particular part of the front is limited, and only in exceptional circumstances are they as numerous as tho battorics, which must therefore wait their turns to shoot, and so upset their programmes. The aeroplane will be fully occupied observing for tlie batteries engaged upon Counter battery work, and even if any are available for the destructive batteries, their observations are very liable to jam uno another if many machines are observing at the same time. It is usually the case that, failing ground observation, the batteries must depend upon tho map, basing their calculations upon the most careful and meticulous registration and calibration.

Care of the Guns. In the battery position itself the chief problems are tlie care of the gups and liio supply of ammunition. In a preiiminary bombardment tho period allotted for any given task should be two or three times at least the period in which the necessary number of rounds could ba tired by all the jpins working at their maximum rate. The mechanism of tho modern heavy gun or howitzer is extremely complicated, and although it works with almgst absolute perfection in the circumstances for which it was designed, it very 600u begins to give trouble if the guns are forced for any length of time. Any mobile gun must bo a compromise between strength that means weight and lightness, lightness that means care of moving, dud it must be employed within the limits of this compromise. A slow rate of fire hns the additional Advantage that a ta.sk can bo performed by less than tho total number of guns in the battery, and that consequently ouo or more gun 6 can always be out of action for cleaning aud overhaul. In common with all machinery, guus require cleaning and lubricating, besides tlie periodic renewal of certain minor parts, such us tho packing of glands, of butlers and recuperators, replenishment with liquid and air, and so forth. Systematic attention to these details means that -there is far less likelihood of breakdown if a sudden spirt is called for, as it certainly will be on tho day of assault. The question of ammunition supply resolves itself into the problem of feeding tho shells from the point where tlicv are unloaded from the lorries to tho breeches of the guns. The former point is determined by tho nearest hard road, and may often bo several hundred yards irom the guns, over a sea of mud and water, or, agaiu, it may be close to the guns and connectcd to these by a short length of Becauville track. In any case, arrangements must bo made to transport tho shell between these two points with maximum rapidity and minimum labour. The work of continually firing a heavy gun is very exhausting, mid tho detachments must be saved every ]x>s* siblo exertion in other directions if a rate of firo is to be kept up without nagging.

It must be remembered that during tho preliminary bombardment firing will bo continuous all day, and will only slacken to a certain exlont at night, when inoro ammunition will have to bo unloaded from tho lorries and carried to tho guns. A. thousand rounds, or 50 long, say, is noh an cxcessivo figuro for a battery's expenditure of ammunition during the 2-1 hours, and every ounce of this must be handled by men who are undergoing tho strain of continual firing.