Green Mace, a British heavy self-propelled anti-aircraft gun prototype in the 1950s [1024x637]

Original description: QF 127/58 SBT X1, known simply as Green Mace, was a British project to develop a Heavy SPAAG (self-propelled anti-aircraft gun) in the 1950s. Developed by Vickers, the specification called for a 5-inch, water cooled gun firing folding-fin sabot dart projectiles at a rate of up to 75 rounds per minute.

Only one proof-of-concept was build, with a 4-inch barrel (102mm). The gun was almost entirely automatic, operated by a single person in a cabin on the side of the vehicle and could fire up to 96 rounds per minute. However, since each ammunition drum held a maximum of 14 rounds, reloading was a frequent event and required a separate crew with a crane to conduct, a process that could take between 10 and 15 minutes.

Green Mace was never accepted into production as the technology it offered was surpassed by guided surface-to-air missile systems which were being successfully developed at the same time.

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