The Ministry of Defence is seeking industry input to replace the Royal Navy’s ageing secondary radar systems aboard Astute- and Vanguard-class submarines, following persistent reliability concerns with the current solution.
According to a pre-procurement notice published on 19 May 2025, the current Secondary Submarine Radar (SSR) is “a portable Commercial OFF The Shelf (COTS) radar that is deployed when the submarine has surfaced, carried to the bridge fin by the crew, clamped to the boat structure, plugged into a vessel power socket and operated.”
It functions as a backup to the submarine’s primary radar, particularly in high-risk environments such as busy shipping areas or when entering or leaving harbour. The system is manually stored inside the submarine and deployed to the bridge fin when surfaced using “a bag and pulley system for the carriage and modified COTS mounts for attachment of the radome and display to the vessel mast/structure respectively.”
However, the Ministry of Defence has flagged performance issues with this setup. The notice states that “the current and previous SSR solutions were subject to high failure rates.”
As part of the Maritime Radar Update Programme (MRUP), the Defence Equipment & Support (DE&S) Delivery Team now intends to launch a formal competition under the Competitive Flexible Procedure, as defined in the Procurement Act 2023. The new radar system will be expected to improve reliability, comply with submarine-specific environmental requirements, and operate more effectively within electromagnetic and safety constraints.
“The goal is to leverage industry capabilities to deliver a more innovative solution that addresses availability issues and aligns better with platform environmental requirements, including electromagnetic compatibility and toxicity,” the notice explains.
A virtual market engagement event is scheduled for Monday 9 June 2025 at 10:00 via Microsoft Teams. Suppliers capable of meeting the technical and commercial criteria will be invited to attend and engage with MoD officials. A Procurement Specific Questionnaire (PSQ) is expected to be released shortly afterwards, around 10 June 2025, though this may be subject to change.
“The capability is required for a period of 5 years… this is anticipated as a timescale of 6-months for replacement from contract award / commencement of contract, followed by 4.5 years of support,” the MoD said.
