The Sunday Times claimed that Type 45 destroyers are able to be heard 100 miles away by Russian submarines.
Rear Admiral Chris Parry, a former director of operational capability for the Ministry of Defence, described the vessels as like ‘a box of spanners’ underwater and that they are ‘as noisy as hell.’
Adm Parry told The Sunday Times: ‘We used to put little wooden wedges between the hatchclips and the hatches in my destroyer to stop them rattling so we could keep the noise down.
‘We have forgotten all about it. Noise suppression has been probably the biggest dirty secret since the end of the Cold War that people have been cheerfully ignoring.’
The investigation also found that jet engines on the warships, which cost £1bn each, have a tendency to break down in warmer seas and were designed to work in the North Atlantic.
The MoD said: ‘Britain’s defence budget is the biggest in Europe and it is growing every year. We are investing £178bn as the UK steps up globally.
‘We are focused on maintaining an affordable programme and getting the best value for the taxpayer to deliver the cutting-edge kit we need to keep Britain safe.’