Einschießen von 21-Zentimeter-Mörsern mit Ballonbeobachtung an der Westfront

Preparations for the ascent of the captive balloon; observation officer fastens the parachute belt and climbs into the basket; orientation at the map board; checking the field telephone connection; ascent of the balloon; observation of the enemy terrain; transmission of the observation to the mortar battery; mortar in camouflaged positions is prepared for operation, loading and firing; transmission of a message to the observer by flashing light signals; soldiers observe the air space; attack of enemy aeroplanes and defence with antiaircraft guns; retrieval of the balloon.