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View Full Version : Multistatics are making my poor old brain hurt! (One for the Kipper Geeks)


Jackonicko
23rd Aug 2017, 14:59
Since my exchange with ‘Bloodhound Loose’ on the Calling Kipper Fleet Veterans thread, I've been pondering his comment:

"You are correct that multi-statics is a broad term and not unique to P8; however, the P8's multi-static capability will be unique."

Bloodhound clearly knows his onions, and I feel very hesitant about raising any question, but………

Reading Clive Radley's book "Sonobuoy History from a UK Perspective", it would seem counter-intuitive that the US would enjoy a really significant or meaningful lead in Multistatics at the moment.

Obviously the RN's Merlins have a Multistatic Active Coherent capability in service, while the US Navy's Multistatic Active capability still rests (or has until VERY recently rested) on the use of impulsive, 'two-bang' SSQ-110 buoys - something the UK trialled (and rejected) in 1998 on the Nimrod MR2, before the 2001 UK decision to concentrate on coherent electro-acoustic active buoys. This eventually led to an MSA trial on Nimrod MR2 in early 2010 using ALFEA in conjunction with BARRA/HIDAR and to an initial MSA search capability on the Nimrod as it left service in early 2010.

In the meantime, under the UK ASSS/MSA (Active Search Sonobuoy System/Multistatic Active) programme, Multistatic data gathering trials took place in 2004, leading to the development of ALFEA by 2006, and the provision of an MSA-capable operational flight programme on the MR.Mk 2’s new ASQ-971 processor in 2008.

By contrast until SSQ-125 is in full frontline operational service (and I’m not certain as to whether that’s the case yet?), and until P-8 Increment 3, it looks as though the US Navy and the Poseidon won't have a coherent active source buoy, even if a basic MAC processing capability was provided with Increment 2. At Increment 2, however, MAC was assessed thus: “the P-8A’s detection capability with the MAC Phase 1 sensor system is strongly dependent on the environmental conditions present in the search area and the actions taken by adversaries to avoid detection. Although the MAC Phase 1 sensor system provides an effective capability in some environments and scenarios, it fails to deliver the full capability described by the Navy P-8A ASW concept of operations and MAC operational requirement documents.”

Not quite working as intended, then!

I understand that the US Navy will eventually have buoys operating at a slightly lower Frequency than ALFEA, which implies a longer range and a larger search area, but with a lower Pd (probability of detection). And that is, of course, assuming that Ultra have not made any progress at all in the last seven years.

I'd love to understand how all of this translates to a 'unique' and superior active multistatic capability, and what I'm missing?

1771 DELETE
23rd Aug 2017, 16:33
I left the fleet in 2005 when testing was on going, it was looking promising, if you were will to put a lot of noise in the water and loose the element of surprise .
I am going to guess that that you will hit the classified wall very quickly with this conversation and probably not get a reply to your P8 specific question, but bear in mind the the Nimrod had Boeing doing a lot of the internal work and when that folded, Boeing took their knowledge back across the Atlantic.

Jackonicko
24th Aug 2017, 08:50
Thanks 1771, I had been so busy reading that the advantage of Multistatic is that a submarine doesn't know where the receivers are, that I hadn't considered the fact that using active buoys at all, whether mono statically, bistatically or Multistatically does put 'noise in the water.' I guess that's the real significance of the advances made in passive buoys that have been demonstrated by the CP-140.

There's much more out there on ASW than I had realised, and I would have thought that as long as detailed tactics and parametrics remain 'off the table' an intelligent conversation ought to be possible. Without one, some of the more extravagant claims for P-8A and MAC just look like unsupported marketing bollocks, and I have enough respect for those making the claims that I am sure that that cannot be the case.

Your point about Nimrod is also well made. The capabilities promised on MRA4 make me realise why people are so unwilling to talk about that aircraft when discussing P-8A - not that it was superior, overall, just that we were very close to having a very advanced capability in service ten years before we will actually have one.