The Royal Navy's newest attack submarine HMS Audacious has been formally commissioned into the fleet during a ceremony at Clyde naval base.
Members of Audacious' company and personnel from the Submarine Flotilla were joined at the Faslane ceremony by the Astute-class nuclear-powered submarine's sponsor Lady Elizabeth Jones.
It marked the completion of extensive tests and sea trials for the 97-metre vessel with Audacious now ready for global operations.
Commander Jim Howard, Commanding Officer of HMS Audacious, said: "As we now move from sea trials into our operational sea training programme, I and the whole ship's company are ready for the challenge ahead.
"This formal commissioning ceremony marks another major milestone in the platform being fully operational and ready for tasking."
According to the Navy, the Astute-class submarines are the largest, most advanced and most powerful attack submarines ever operated by the Senior Service.
The vessels, which are equipped with sophisticated sensors, can carry Tomahawk Land Attack Cruise Missiles and Spearfish heavyweight torpedos – HMS Audacious recently conducted trials of the upgraded Spearfish torpedo in the Bahamas.
The Astute-class submarines will gradually replace the Trafalgar-class and can circumnavigate the globe while submerged, producing their own oxygen and drinking water.
They are also the Navy's quietest class of submarines yet and the first to be fitted without optical periscopes, instead using high-spec video technology.
During the ceremony, Audacious' company formed platoons on the jetty and were inspected by Lady Jones.
She then addressed those gathered for the occasion and cut the commissioning cake.
Commodore Jim Perks, head of the Royal Navy Submarine Service, said the commissioning ceremony is an "extremely important day in the life of HMS Audacious".
"Throughout this pandemic, Audacious has delivered her extensive trials programme without fuss and with considerable style.
"I wish the boat, crew and their families all the very best for the future and look forward to seeing her deliver on operations."
HMS Audacious joins her sister vessels HMS Astute, HMS Artful and HMS Ambush in the fleet.
The boats will eventually be joined by HMS Anson, HMS Agamemnon and HMS Agincourt and will all operate from Clyde naval base.
It was announced last week that £170m was being invested to design the replacement of the Astute-class submarines for when they leave service.
Each Astute-class boat is expected to serve for at least 25 years.