Anyone thinking about future ASW drones shall read this article, at least the first one. It is clear and very logical.
We are living in a world that subs cannot be a good ASW node anymore. Subs are getting more quiet, and thus ASW tactics is shifting toward active multi-static. Sub cannot ping, because its only defensive measure is stealth. Thus, looking for a UUV to, at least decouple the "pinger" off board is critically important.
Type-A: Bi-static ASW needs coordination of "pinger" and "listener". If pinger pings at specified time, position and direction, the listener can analyze the reflection. Not much different from S2087 having VDS and TASS separated. This is listed as the first option as ASW UUV in the 1st article.
Type-B: In addition to this, multi-static ASW needs to transfer the accumulated acoustic signal to an analysis node (mother sub), to perform cross correlation analysis of the data, which I believe is the heart of multi-static ASW. This is listed as the second option, and clearly noted technically not easy to do.
By the way, the second issue is largely solved in surface vessel. You just need to use data link. (If need to be stealthy, you can use sat-com, laser communication, or even acoustic, all much easier than those underwater.)
I think the 1st step will be the UUV or USV of type-A. Since it needs power (pinging requires electricity), making it small is not easy (especially for sub-deployed UUV). Making its deploy speed fast is also not easy, not to say about its endurance.
In the surface vessel world, if you want to survey a certain area of sea (say, 100x100km2), you shall deploy slow, long range USVs. For calm water, a 10m-class USV with FLASH dipping sonar is already there. But, it cannot be used for TF escort for sure. For TF escort, I think there is a need for ocean-going pinger to keep the quiet T26 silent. The pinger can be either type-A or B, but need to be ocean going. It could be either manned or unmanned.
- one option is to make it, "snorting small SSK".
- another option is to make a modern version of Flower-class ASW Corvettes. Relatively simple OPV-sized ship to taw (at least) VDS part of multi-static ASW sonar (type-A), or also passive TASS (type-B).
This could be MHPC, or even T31e-ASW capable version.