First directions to protect the troops against aircrafts
On 18 October 1915 the Bulgarian High Command, at Kjustendil, published the Order on Field Army Nr. 48, signed by maj. gen. Nikola Zhekov, detailing the measures that should be taken to protect the troops against the activity of enemy aircrafts and airships. The text was characterized by a clear underestimate of the power of the air force, whose principal task, if not the only one, was supposed to be reconnaissance, without any concern for its positive use for attack. As weapons aircrafts and airships were regarded as not able to get any appreciable or durable result, since the drop of single bombs, the fire with machine guns or even with light guns could not cause an effective damage to the troops, having only a psychological effect. In addition the flying machines were regarded as very vulnerable to infantry and artillery fire. So even the observation was not an easy task for them, having to fly high to avoid to be hit.
The potential of the aviation was considered very limited. Aircrafts or airships could observe only great and easy visible features, like buildings, marching columns, camps, tents or fortifications, especially when they had regular shape, were well lighted up and their colour showed up against the ground. Troops and supply trains were well observable when moving on macadam road or bridges, but were less discernible when moving on country roads or on fields. Single men or little group of soldiers were almost invisible. Rain, fog or night darkness blocked the air observation, even if the latest pattern of aircrafts were equipped with searchlight and flares.
that the British and French contingents landed at
a) Marching troops in column should interrupt the movement, split between the two sides of the road and lie down in the ballast or, if possible, hide among shrubs or trees. It was very important that the men did not scatter, since the march should be resumed as soon as possible. Artillery, cavalry and supply trains should interrupt their movement and, if possible, hide near the road. Everything should be done calmly and neatly, without confusion, and, as soon as the aircraft had gone away, everybody should quickly take its place in order to resume the march at once. In no case such stops could be used as a pretext not to arrive promptly where the unit had been ordered to go.
b) Every kind of fortification should be well masked also against air observation.
c) Transports and stores, when could not be placed in built-up areas, should be masked from above with bushes or arranged in concealed fold of the ground.
d) When an enemy aircraft was sighted, the troops should inform the nearest command by phone or telegraph, in order to take prompt measures to fire against it.
e) During the battles special detachments, supported by some machine guns and certain artillery batteries, should be designated to fire against enemy aircrafts, while the remaining units should keep their action, without paying attention to them. Disorderly shots were not only useless, but often also harmful, owing to the fall of shells and bullets.
f) During the marches the task of firing against aircrafts should be assigned to the half-companies of the vanguard battalions, while during the rests certain companies should be placed in positions fit for observation for a quick reaction. In addition some machine guns and artillery pieces should be deployed in suitable emplacements and arranged to fire at great angles.
g) Guns and machine guns chosen to fire against aircrafts should be well masked from above and shot before the target along its course of flight.
The presence of the enemy aviation required special care during the movement and the concentration of reserve, manoeuvre troops and reinforcements that should be carried before dawn. Broadly speaking, the troops should move preferably by night or foggy weather. Finally the Order stressed that enemy aircrafts or airships landed for whatever reason should be taken by the nearest unit, carefully preserving the apparatus up to the arrival of the experts sent to store it.