A German observation kite balloon in Lorraine in 1915.

January 20, Neider Morschweiler—The increased importance of artillery in the trench warfare in the West and the general shell shortage on both sides made it critical that the artillery be used accurately—that the shells would land where the artillerymen wanted them to. This could be difficult for the artillery to verify directly; artillery ranges were often so long that visual confirmation was not possible from the ground, and enemy positions were often located on the reverse slopes of hills to prevent such easy sighting and to minimize the resulting damage. As a result, artillery spotters—men in elevated positions who would have a better view of where the shells would fall—became an important requirement. Where possible, spotters would use buildings, church spires, etc., but they were not always available and quickly became targets for enemy artillery. An increasingly-used alternative was balloons, which could have an even better view without being vulnerable to enemy artillery, and could also perform other extensive reconnaissance on enemy positions. The first, spherical designs were not suited for poor weather or high winds, but soon “kite balloons” were developed which could steer, after a fashion, and remain aloft in non-ideal conditions. Balloons were most often filled with hydrogen; early in the war, before the widespread use of incendiary weapons, this was not a problem.

The task of taking down enemy balloons was most naturally suited to planes. However, in early 1915 their armaments were crude at best, as the forward-mounted machine gun had yet to be perfected. This did not deter the flyers, however. On January 20, a French two-man Voisin plane managed to destroy a German kite balloon in Alsace by dropping a bomb and 250 darts on it—these did enough damage to its envelope to bring it down.

Sources include: Randal Gray, Chronicle of the First World War (Volume I).