The Royal Navy frigate HMS Sutherland has successfully fired her main gun during capability trials at sea, a key step in the warship’s return to front-line service, the Royal Navy has said. The Type 23 frigate, known by her ship’s company as the Fighting Clan, said she had spent the last two weeks busy at sea, continuing essential capability trials for operations with the successful firing of her 4.5-inch Mk8 gun, alongside her ceremonial saluti…