Re: Japan's military build-up
So what's about PRC's Submarine!? They have a big force and still increase it.
In this regard (excluding the SSBN subs), the Chinese sub force is basically a three fold force.
1) Nuclear attack subs.
2) Newer Diesel Electric subs.
3) Older deisel subs.
The nuclear subs are all too loud at this point. They are nuclear, and they can sustain high speeds and keep up with their own high value vessels to protect them, or attempt to intercept adversaries. But the Han (Type 091) are old and near the end of their service life and far too loud. The PLAN tried with the Type 093 to create a newer class which was a lot quieter, but apparently, though the vessels were better than the Hans they were still too loud. The PLAN built two of those, and then are in the process of building four more improved Type 093s which may come up to the Victor III Russian boat level of quietness. It is my understanding that the Type 095 is now being built which they hope will be more quiet...perhaps up to the US Los Angeles class Flight II boats. Such a level represents a very crdible threat, but is still two generations behind the state of the art Russian and US boats. And there will be very small numbers of them for quit some time.
The newer diesel electrics consist of the Kilos (12), the Song or Type 039 (13), and the Yuan or Typre 041 (7) submarines . All are decent vessels and failrly quiet. The newer Yuan class supposeldy has AIP, which will improve its abaility to stay hidden for longer periods of time. However, as diesel electrics, they do not have the speed or the ability to sustain operations in order to escort high value units or very ably intercept high speed adversaries on the high sea. They either have to wait at choke points, or they have to have good enough intelligence (G2) to know where an adversary is going to be and then go there and wait for them. Adversaries know these things and will conduct very stringent ASW operations in those areas.
The older Diesel Electrics, ie Ming or Type 035 (17) are a much older design, although (amazingly) four of them were still built with significant updates into the 2000s. They would be good for coastal water defense, or intelliegence gathering and surveillance, or in Task Force (or Packs) with other, newer diesel electrics where they could provide cover for those more quiet boats.
The JMSDF has trained, in very realsitic operations and in fact against operating Russian boats, both nuclear and diesel/electrics. They have decades of experience and equipment that has been developed and honed specifically for this task. During the cold war, their major task would have been to provide broad, outer ring ASW operations for the US Navy who would use their own escorts for inner ring ASW while the carriers were used for offensive operations.
The two nations have worked on every imagineable ASW scenario for deacdes together and are very good at it, with a LOT of new, very capable vessels. That is why so many say that one cannot and should not underestimate the capabilities of the JMSDF in this regard.
These Akizuki DDGs are the apex and pinnacle of that long line of development and expertise, along with the Hyugas. The Hyugas would provide significant helo ASW capabilities and numbers to saturate any area suspected of harboring adversary submarines.
I'm from the Czech Republic, yes, a country which doesn't have access to sea ... anyway, you mentioned a fairly high displacement of 19DD so I was thinking if it can't be also (in addition to many other things) because the antennas of the FCS-3A radar are distributed, I mean there are four of them foreship and another four atop the hangar? What do you think? By the way, I've read there are also two engine rooms (with two turbines in each of them) on 19DD. Do you think this "redundancy" is important? Thanks!