There are two versions of the famous WWI fighter plane, the Spad VII and the Spad XIII.

The Spad VII was a French-made single-gun biplane that first flew in July 1916 it is famous as the plane used by the volunteer American pilots in the Escadrille Lafayette, which eventually became the 103rd Aero Squadron.

The Spad XIII had two Vickers 303 machine guns to counter the newer twin-gun German designs, and was fielded in August of 1917. It was the plane most identified with Eddie Rickenbacker's Hat-in-the-Ring Squadron. There was a lesser-known earlier version that was a two-seater, a "pusher" design (The prop was at the back of the plane) with the gunner's nacelle in front of the pilot so he could fire unobstructed. It was heavier and slower than a single-seat fighter, for obvious reasons, and so wasn't very successful.

A spad is a spike that looks similar to a small flat key, it has a round head with a hole and a long straight shaft with a round point. The spad is driven into a wooden plug in a hole in the roof of an underground mine by a spad gun, from this spad a plumbline is threaded.

The spads become survey station locations including the pointer spad station that allows the forman to align enteries from the main spad station. Each spads location is marked with it's station number using a brass tag, mining survey's are critical in tracking the mining process. Spad locations are considered sacred -- a missing spad in a critical location could create chaos, causing countless hours of additional work regaining control of the mine survey. In early mining days spad station surveying was often the means of determining a miners wages, by mapping advances in the coal seams.

Spad (?), n. (Mining)

A nail one or two inches long, of iron, brass, tin, or tinner iron, with a hole through the flattened head, used to mark stations in underground surveying.

 

© Webster 1913

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