Adrian helmet

The M15 Adrian helmet (French: Casque Adrian) was a combat helmet issued to the French Army during World War I. It was the first standard helmet of the French Army and was designed when millions of French troops were engaged in trench warfare, and head wounds from the falling shrapnel generated by the new technique of indirect fire became a frequent cause of battlefield casualties. Introduced in 1915, it was the first modern steel helmet and it served as the basic helmet of many armies well into the 1930s. Initially issued to infantry soldiers, in modified form they were also issued to cavalry and tank crews. A subsequent version, the M26, was used during World War II

At the outbreak of World War I in August 1914 soldiers in the French Army wore the standard kepi cap, which provided no protection against injury. The early stages of trench warfare proved that even basic protection of the head would result in a significantly lower mortality rate among front-line soldiers. By the beginning of 1915 a rudimentary steel skull-cap (calotte métallique, cervelière) was being issued to be worn under the kepi.

Consequently, the French staff ordered development of a metal helmet that could protect soldiers from the shrapnel of exploding artillery shells. Since soldiers in trenches were also vulnerable to shrapnel exploding above their heads, a deflector crest was added along the helmet's axis. Branch insignia in the form of a grenade for line infantry and cavalry, a bugle horn for chasseurs, crossed cannon for artillery, an anchor for colonial troops and a crescent for North African units was attached to the front. Contrary to common misconception, the M15 helmet was not designed to protect the wearer from direct impact by rifle or machine gun bullets. The resulting headgear was credited to Intendant-General August-Louis Adrian.

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