Caribbean wrote: ↑21 Dec 2021, 12:45 ... I think it would not be unreasonable to expect all RN vessels to carry at least basic ASW/ mine avoidance sonar, alongside SSTD (even the next generation of OPVs)
By sacrificing what? Each ASW system will require ~5 more crews, at least. For 5 T31 and 8 OPVs, we need 75 more crew. In other words, we need to put nearly one T31 into extended readiness, I'm afraid?
<On OPV>
Submarine is very expensive and complicated weapon. If all OPVs are required to handle it in some sense, why not all OPV need to handle super-sonic ASM with Aster30?
History tells that submarine is a very tough target to kill, but by using air-asset, its threat can be significantly reduced. This is simply because modern submarine is very quiet, but it is very slow when being quiet.
Mine avoidance sonar can be there. It is compact and simple. But, I am not sure if it can "detect" mines well. Sending a REMUS pod before deploying there, or using USV-MCM drones to pre-survey the area, will do it much better? Not sure.
<on T31>
It is debatable I agree. But, I think adding CAPTAS-4CI (a compact version of CAPTAS-4) to 2 of the 5 T31s, will be better than adding a hull sonar to all 5 T31s. French FDI is a frigate specifically designed with, "normal (noisy) hull with very good sonar". France is an experienced Navy, so they know what they do, to some extent. at least. So. "big sonar on noisy ship" has some rationale.
If the "ping" sound is the same between CAPTAS-4 and CAPTAS-4CI, it can at least "pretend" to be a Type-26 from a distance, observed from a sub.