Thales UK will upgrade three of the UK Royal Navy’s Trafalgar-class and three Astute-class submarines with the Sonar 2076 Stage 5 system, under a contract awarded by BAE Systems.

Following the completion of the upgrade, the submarines currently fitted with the 2076 Stage 4 system will be installed with the 2076 Stage 5 system across the navy’s nuclear-powered attack submarine fleet.

The Stage 5 inboard replacement (IR) contract satisfies the navy’s changing mission requirements in terms of reduced through-life costs and the need for rapid capability insertions of new hardware, software functionality and new algorithms.

In addition, the upgrade also delivers an open architecture that allows a high degree of commonality with the future Astute and Vanguard-class submarines, and supports the MoD’s vision for the evolution of a common sonar and combat system across the navy’s submarine fleet.

The Stage 5 IR contract is the latest in a series of developments to improve the capability, efficiency and through-life cost of the system.

Work on the Stage 5 IR contract will include equipment procurement and manufacture and platform upgrades, which is scheduled to be completed by the end of 2011.