The attack against fortified positions

The Bulgarian Инструкция за употреблението н службата въ крепостно-обсадната артилерия при атака и отбрана на крепост ите и изобщо укрепените позиции (Instructions for the employment and the service in the fortress-siege artillery attacking and defending strongholds and fortified positions in general) published in 1906 was an ample text, detailing all the actions that the fortress artillery could be charged to carry in defensive, but especially in offensive combats. It dealt the task of the fortress artillery during any kind of action against a fortified position, analysing the problems concerning the direction of the siege, the choice of the front of the attack, the ideation of the plan for the attack and its execution. Finally it considered the problem relating with the defence of a fortified position.

These Instructions were revised and completed by a text published by the Engineers Inspection in 1911, the Наставление за действията на войски те при атаката и отбраната на крепостите (Direction for the action of the troops attacking and defending strongholds), directly inspired by the regulations adopted by the French and German Army. It was conceived as a general direction addressed to all the Army branches, but it focused especially on the duties and the tasks specific to the engineers. Therefore it did not deal specifically with the features of the fortress guns.

The Instructions published in 1906 comprised three sections :

I. The attack on a fortress : the tasks of the artillery in the different kinds of attack (by surprise, by investment, by bombardment, by force and by gradual attack or siege); the means for conduct of a siege; the choice of the front for the main attack; the plan for the attack; the choice of the place for the siege park; the arrangement and reconnaissance of the artillery positions; the conduct of fire, the various kinds of projectiles and their use, the service at the siege batteries.

II. The defence of a fortress : the task and the arrangement of the fortress artillery; the weapons of the fortress artillery; the task of the engineers; the ammunition and food supplies and the conduct of the defence.

III. The attack and defence of forts and the defence of the coasts.

Generalities. The attack on a fortress arose from the development of the field operations and should be conducted on the basis of the same tactical rules, but with the full use of the siege and fortress artillery and of all the technical resources of the modern warfare. For this reason it was very complex and needed a strong and sustained training in peacetime. The text took into account the duty of the fortress artillery during the surprise attack, the investment, by force, the bombardment, the storming, the gradual attack, and the regular siege. It paid special attention to the storm that was described as a bold and vigorous action directed to seize a detached fort or the fortress itself, after a mass artillery shellfire had overwhelmed the enemy artillery and disheartened the spirits of the defenders.

The preparation of the attack. The attack on fortified positions should be preceded by an accurate reconnaissance carried out at first by cavalry, and then by infantry patrols lead by officers, balloons and observation posts. The fight came immediately after the reconnaissance, and the fire preparation should be planned accurately. The approaching march should be made on a broad front and in several columns, to muddle up the enemy about direction of the main attack. While the infantry strengthened the ground previously occupied, the artillery started a powerful firing preparation. If the assault positions were reached during the night, the attack could start in the middle of the night itself or at dawn, and in that case the artillery stopped firing. In open ground the troops stood out of the range of the enemy rifle fire, waiting the night to occupy and entrench their positions. During the preparation of the attack, the artillery took possession of covered emplacements, the reconnaissance went on by every possible means, and some key points were occupied by skirmishes.

The attack. At dawn artillery opened a concentric fire. The howitzers, alone or together with the light field artillery, fired above the columns and the batteries. At first they should neutralize the enemy artillery in order to cover the movements of the field artillery, then fired at the defender’s batteries, that were impeding the advance of the infantry. In the meantime the field artillery shelled with shrapnel the approaches to the enemy artillery emplacements. Afterwards the heavy artillery fired at the enemy strongholds to demolish shelters and parapets.

During the artillery shellfire the infantry should advance quickly and without stops up to around 300 paces from the enemy line, where it dug in. This advance should be as strong as possible, in order to force the enemy to expose himself, making more effective the fire of the attacking artillery. If the enemy fire made the movement impossible by daylight, the infantry should advance at night.

The final attack should be prepared by a continuous reconnaissance of the ground, in order to determine the level of resistance of the enemy defences. The engineers should remove every hindrance, working under cover of darkness or fog. The passages opened should keep clear by means of the infantry fire. The ways of attack were marked with white marks (black if the ground was covered with snow).

The decisive assault was carried out at the break of day. After a convenient rest, the troops chosen for the attack reached the starting points by night, preceded by a curtain of shooters. At an agreed signal the shooters and the engineers advanced, followed by the attacking columns. Then, 50 paces away from the enemy line, the shooters threw to the ground and opened fire, while the attacking columns through the prearranged approaches charged the enemy with the bayonet. In meantime the artillery with explosive shells and shrapnel cut the communications between the enemy line and the backup troops. After the breakthrough, the attacking columns pursued the enemy, while the shooters grouped together.