Introduction

Specificity of a block of combat

The general problems of ventilation and air-conditioning are the same ones, for the quartering and the blocks of combat: to be able to breathe normally and not to be inconvenienced by the temperature and moisture.

However an important component carries it in a block of combat: during the shootings the pollutant gases are produced in very great quantity and are particularly concentrated in the gun of the weapons and the empty cases. The air of the casemate very quickly becomes unbreathable.

In this document we are interested, particularly, with the ventilation of a block of combat.

Insulation of the block of combat

The first precaution consists in isolating the block from combat by a tight door and feeding the block by fresh air drawn from quartering. When the doors remain open (most of the time), this device is not used. In the event of alarm, the doors are closed and the device between concerned.

Fressinea (SFAM)

At the end of the gallery of quartering, one sees the tight door which insulates the active casemate.

Holy Agnes (SFAM)

Behind the tight doors, isolating quartering and block 2 from combat, a powerful ventilator draws the fresh air of quartering.

Diagram - provisional of the ventilation of a block of combat

Treatment of the empty casings

The casings of the weapons of small gauge (FM, JM, AC, etc) are not reusable. They are eliminated by a flexible sheath connecting the cylinder head from the weapons and the outside of the work.

Simserhof (SF Rohrbach)

Under the JM (on the right) one can see the sheath of ejection of the casings.

Case of the casings large gauge

The empty casings, residues of the artillery ammunition and principal pollutant gas vectors, are recovered in a tight room. The latter is broken down by a circuit of extraction of the foul air

Holy Agnes (SFAM)

Door seals of the receiver of casings. One can see the two sheaths: air flow pure (red) and departure of foul air (yellow) which make it possible to cleanse the casings before re-use.

Diagram - provisional of the ventilation of a block of combat

Pieces of ordnance

Ventilation. The solution (selected inter alia by the Italian Genius) consists in isolating the block from combat by a door seals and equipping serving them of the weapons with individual masks connected, by a flexible sheath, with a pure air flow coming from quartering. But the solution is not very practical for the men of crew and neither the problems of the elimination of persistent pollutant gases nor the problem of the entry of poison gases solves.

The solution adopted for the Maginot Line consists in completely isolating the block from combat and putting it in light overpressure. This light overpressure then makes it possible to eliminate pollutant gases present in the heart from the guns. Indeed, when after the shooting the cylinder head opens, a draught pushes these gases towards the outside of the work and, at the same time, is opposed to the entry possible poison gases.

So that it is effectively maintained, this overpressure (higher than that reigning in quartering) has a considerable cost because it requires particular installations:

- need for one hopper at the entry of the block;

- need for tight crenels. The sealing is obtained by a kneecap which encloses the flight of the gun.

- need for an armament specific to the fortification. Indeed, for reason of sealing, the weapons and their embrasures must be adapted the ones to the others. This concept of specific armament is besides a characteristic of fortification CORF. He was wanted, inter alia, to avoid the error made in 1915 when an inappropriate order made disarm the fortifications of the time (equipped with nonspecific artillery material) to the profit of the troops of countryside. Many forts, without defense, then fell to the hands from the Germans and only at the price very heavy human losses could be begun again.

Museum of Fermont (SF Crusnes)

On this trumelage (2 machine-guns and a gun of 25mm) one can see the kneecap returning seals the crenel of the weapon.

Diagram - provisional of the ventilation of a block of combat

Room of neutralization of block

During the shootings, the quantity of air necessary to the overpressure of the block of combat is too important to be taken in quartering. The block thus lays out, for its phases of combat, of an autonomous room of ventilation. then:

it ventilator - fresh air which activates the air coming from quartering is stopped;

it room of ventilation of block draws the air outside the block;

- the air is purified in the filters so necessary;

it ventilator - air gauze sends the air to join the sheaths of distribution of the circuit - fresh air. In certain sheaths the pure air circulation is then reversed.

Diagram - final of the ventilation of a block of combat

Schoenenbourg (SF Haguenau)

Bell of air intake of a room of neutralization of block. It is the adopted solution when, for various reasons, the air cannot be taken in frontage of block.

Bambesch (SF Faulquemont)

Room of neutralization of block

Puzzle of entertainment

Reconstitute the image of the room of neutralization of B2 of the co. Agnes (SFAM) while clicking on the parts of the puzzle. The rules of the game, simple, are to be discovered intuitively.

Excel work!