Oerlikon 30 mm twin cannon
The Oerlikon 30 mm twin cannon is an anti aircraft gun used by the Royal Navy. They were fitted to Type 42 destroyers after the Falklands War to improve defence against air attack.
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Wikipedia
The Oerlikon 30 mm twin cannon is an anti aircraft gun used by the Royal Navy. They were fitted to Type 42 destroyers after the Falklands War to improve defence against air attack.