Oerlikon is a (originally) Swiss
manufacturing firm. There's a cool story about what it originally manufactured which I swear I will track down one day. In any case, the name became known worldwide after World War I
, when Oerlikon began to produce a line of light, rapid-firing gas-operated cannon
. These weapons were ideal for early anti-aircraft
mounts; in the early years of World War II
were buying their 20mm AA
guns from Oerlikon (thus the metric notation
, so strange to see in the U.S. and British Navies). As France
fell, however, the British became concerned about their ability to tranship these weapons from Switzerland
, and one of the weapon's designers (Antoine Gazda
, an Austrian)was sent to the U.S. He settled in Rhode Island
with a highly secret and coveted
set of blueprints
for the 20mm turret-mount AA gun for naval use.
By the end of the war, the 20mm gun was considered too light for serious AA use, having been supplanted by 5" and 40mm mounts; however, they were still mounted on ships in large numbers. This was partially for the psychological boost provided to seamen through being able to fire back, however ineffectual that fire may have been. This is the weapon that is referred to colloquially as the 'Oerlikon gun.' It was manufactured by both the British and the Americans.
Oerlikon remains in business today, having moved into aerospace engineering, defense systems integration, and electronics among other areas. It has subsidiaries around the world, some of which have split off (Oerlikon Canada is, I believe, a separate entity). They continue to manufacture light, fast automatic cannon, typically for aircraft mounting in modern jet fighters and helicopters.