The procurement landscape for the UK submarine industrial base has been underscored by the successful completion of the initial underwater dive for HMS Agamemnon, the sixth vessel in the Astute Class programme.
This event, conducted in the dock facilities at BAE Systems in Barrow-in-Furness, represents a crucial progression in the manufacturing and commissioning cycle, directly impacting the sustained workload and technical requirements placed upon the defence supply chain.
The successful ‘trim dive’ is a prerequisite for a submarine’s transition from yard construction to active sea trials and eventual integration into the Royal Navy fleet, currently composed of HMS Astute, HMS Ambush, HMS Artful, HMS Audacious, and HMS Anson. This phase, managed by BAE Systems in conjunction with the Royal Navy crew and monitored by the Submarine Delivery Agency (SDA) and MOD naval architects, involved two distinct, high-precision activities: the basin dive and the trim and inclining experiment.
The basin dive focused on testing critical on-board systems, primarily the ballast tanks, which are essential for controlling the vessel’s surfacing capability. This stage validates the performance of multiple industrial sub-systems, including high-pressure air and hydraulics, structural integrity, and complex fluid dynamics management systems. For companies supplying these specialized components, the successful execution of this test confirms the rigorous quality and integration standards required for continued programme participation.
Crucially, the trim and inclining experiment confirmed the submarine’s precise centre of gravity, a measurement vital for calculating stability and predicting in-service performance. This operation required the precise manipulation of 16 tonnes of lead weights on board the 7,400-tonne vessel, with measurements taken in both surfaced and submerged conditions. This highly technical process emphasizes the sustained demand for bespoke naval architecture support, precision engineering, and specialized measurement equipment required for the final stages of a nuclear submarine build programme.
With HMS Agamemnon, named in April 2024 and launched in October 2024, now moving closer to service, the supply chain should anticipate a forthcoming shift in focus from new-build manufacturing to through-life support and in-service maintenance contracts. The validation of key platform systems during these initial dives solidifies the long-term requirement for spare parts provision, technical data package maintenance, system upgrades, and specialized support services across the entire 97-metre, Astute Class fleet, ensuring consistent opportunities for businesses prepared to meet the stringent safety and technical standards of the SDA.
Image: HMS Agamemnon – Credit: Royal Navy
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Post written by: Vicky Maggiani
Vicky has worked in media for over 25 years and has a wealth of experience in editing and creating copy for a variety of sectors.
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