The Type 42 destroyer, due to head south from the naval base this morning, was visited by Birgitte, The Duchess of Gloucester.
She was the ship's sponsor when the ship was launched in 1982.
The Duchess met members of the ship's company ahead of
their deployment to the Falkland Islands and other British south Atlantic territories.
Lieutenant Commander Douggie Ward, the ship's Logistics Officer, said sailors on board were delighted to meet the royal guest.
He said: 'It was certainly a morale booster.'
During her passage south the ship will be on hand to help with counter-narcotic operations, search and rescue missions and humanitarian relief.
When she arrives in the Falkland Islands she will become the lead Royal Navy presence in the region, supported by the patrol vessel HMS Clyde and Royal Fleet Auxiliary vessel Gold Rover.
HMS Gloucester's commanding officer, Commander Iain Lower, said: 'This deployment follows on from a huge amount of effort and work by my ship's company.'
HMS Gloucester is due home in Portsmouth in December.
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