Britain’s naval power has reached another major milestone after HMS Agamemnon, the Royal Navy’s newest Astute Class attack submarine, sailed from Barrow-in-Furness to begin sea trials.
The formidable nuclear-powered submarine, affectionately nicknamed “Awesome Aggie”, is the sixth of seven Astute Class boats being built for the Royal Navy and represents some of the finest engineering and shipbuilding expertise in the United Kingdom.
HMS Agamemnon has now departed the BAE Systems shipyard in Cumbria and will undergo an intensive programme of sea trials before entering active service with the Royal Navy.
At 97 metres long and weighing around 7,400 tonnes, the Astute Class boats are the largest and most powerful attack submarines ever operated by the Royal Navy.
And the technology at the heart of Agamemnon is British.
Her nuclear reactor was produced by Rolls-Royce Submarines in Derby, demonstrating once again the vital role played by British industry, including the Midlands, in maintaining the country’s defence capabilities.
The reactor is designed so that the submarine will not need to be refuelled throughout her operational life.
A formidable British fighting machine
HMS Agamemnon has been designed to operate discreetly beneath the waves while carrying out some of the Royal Navy’s most demanding missions.
Her capabilities include anti-submarine warfare, intelligence gathering and precision strikes.
She will be armed with heavyweight Spearfish torpedoes as well as Tomahawk IV land attack missiles, capable of striking targets more than 1,000 miles away.
Astute Class submarines also have an important role supporting Britain’s continuous at-sea nuclear deterrent, protecting maritime task groups and supporting UK, NATO and coalition operations.
Behind the extraordinary vessel are thousands of British workers.
Engineers, technicians and specialists from BAE Systems and the wider Defence Nuclear Enterprise have worked alongside Agamemnon’s ship’s company to bring the submarine to this stage.
The project draws upon expertise stretching far beyond Barrow, sustaining a national network of highly skilled jobs and specialist British industrial capabilities.
More than 14,000 roles in Barrow-in-Furness are supported by defence nuclear work, while the wider Defence Nuclear Enterprise supports more than 47,000 jobs across the United Kingdom.
Britain’s submarine-building tradition continues
HMS Agamemnon formally entered the Royal Navy when she was commissioned by His Majesty the King on September 22, 2025.
She is the sixth Royal Navy vessel to carry the historic name Agamemnon.
Her departure for sea trials is not the end of Britain’s submarine-building programme.
The seventh and final Astute Class submarine, HMS Achilles, is already at an advanced stage of construction in Barrow.
Beyond that comes the next generation.
The Astute Class is due to be succeeded from the late 2030s by up to 12 new SSN-AUKUS nuclear-powered attack submarines, with steel for the first boat expected to be cut in Barrow next year.
The programme means the skills, knowledge and industrial infrastructure required to build some of the most sophisticated submarines on Earth can continue to be maintained here in the United Kingdom.
At a time when the international security environment is becoming increasingly uncertain, HMS Agamemnon is also a powerful reminder of something Britain should never take for granted, its ability to design, build and operate world-class military technology.
From the shipyards of Barrow to the nuclear engineers of Derby and the thousands of people working throughout the supply chain, “Awesome Aggie” is a formidable product of British skill.
Soon, she will be beneath the waves, helping to protect the United Kingdom and its allies.
And she was built in Britain.
Main Image: MOD Crown Copyright News / Editorial Licence.
