The House of Commons defence committee urged the UK Government on Thursday, October 22, to keep its remaining Type 23 frigates equipped with towed arrays in service until new Type 26 frigates replace them one-for-one.
In its report “Defence in the High North”, the committee counted five frigates fitted with Sonar 2087 against a Ministry of Defence (MOD) requirement for eight.
"Towed array sonar-equipped frigates are central to detecting and tracking hostile submarines in the High North, the North Atlantic and UK waters, including around the UK's nuclear deterrent bases," the committee said. It added that the shortfall, "raises questions about whether the transition from the Type 23 to the Type 26 frigate capability has been properly managed."
The frigate fleet fell from seven to five when HMS Richmond and HMS Iron Duke were decommissioned in mid-2026. Richmond carried Sonar 2087. The MOD had planned to fit a towed array to Iron Duke but cancelled the conversion.
The report sets out a scenario in which two Type 26 frigates being built for the Royal Navy are sold to Norway. Under that scenario, towed-array frigate numbers would stay as low as five for three years and reach eight only in 2037, according to analysis published in Defence Analysis.
Norway's ships are due to be built on the Clyde in slots alongside the UK programme.
In June, the MOD said it was considering whether build slots set aside for the Royal Navy could be offered to Norway. It said all eight ships would still go to the UK in the late 2020s and 2030s.
Responding to the report, the MOD said it recognised the Russian threat and was investing heavily in protecting undersea cables. The government is expected to respond formally within two months.
