UK Defence Forum

I'd be surprised if it was wasn't in there, seems like a no-brainer, remove the CMC and add a couple of VPM.

Might even be a cheaper option in the long run, allowing for more weapons in the ready to fire position, reducing crew and storage requirements.

shark bait wrote:Might even be a cheaper option in the long run, allowing for more weapons in the ready to fire position

Cheaper is like efficient: to get the job done for less money

However, the overall solution (in whatever way the Tomahawks are going to be launched) also needs to be effective, i.e. get the job done. In this respect the Tomahawk is still a 1970s design in that it relies on low altitude to hide from radars.
- and that is not going to change, even though downward-looking radars are proliferating on small AWACS planes and aerostat blimps

There might be some mileage in the GPS III M-code upgrades, which will also improve anti-jamming and anti-spoofing capabilities.
- the same Raytheon that is the prime for Tomahawk makes the satellite/ earth interface part (OCX) for the GPS III "upgrade"

An update by DID also says that "Raytheon and the Navy are looking for more, with a focus on mature technologies to cut down program risk. An ESM system for noticing and geolocating emissions has already begun testing. Raytheon personnel stress its quality, to the point that Navigation via Signals of Opportunity (NAVSOP) might be possible as a backup to GPS. During the attack run, ESM can allow the Tomahawk to home in on an active enemy ship or air defense radars, or even on other intercepted signals. That begins to add autonomous moving target capability" ... like ships

To cut the long intro short, going VLS/ VPM rather than sticking to the "thru the torp tubes" method will be a great "future proofing" insurance against the Tomahawk's impending obsolescense
- e.g. the above mentioned ESM homing (as the third method for targeting) is already funded, jointly by Norway & Oz, for JSM... made by BAE (but in Australia)
- and as our subs with a VPM on them will be a long time in coming, there is a bridging solution (don't know when the Tomahawks are due for re-lifing) as in " Encapsulated launch from a standard torpedo tube based on a JSM baseline configuration utilizing a thrust vector controlled booster are the ground rules for the studies. Babcock is responsible for developing the canister concept. The system will only require minor changes to the JSM airframe; however, all internal components will be kept unchanged. The operational capabilities of NSM-SL will be similar to JSM with stand off ranges well beyond 300 km. Kongsberg is aiming to be ready for the test and integration firings on the Next Generation Norwegian Submarines in 2025." http://www.navyrecognition.com/index.ph ... ystem.html

Someone could say that range is everything? We can go back to the need for actually making it through, to the target.

ArmChairCivvy wrote:

shark bait wrote:Fully expect it to be a Dreadnought with the trident tubes removed

A fat hunter-killer ?
- aren't they meant to be able to move and manoeuvre fast... which makes for a very different noise generation than with the boomers lazily moving about

SSN-21 Is positively pork compared to a 774, but she's quite fast. The next generation of our attack boats might well go down a similar path, to the benefits of payload capacity and sensor size.

There simply has to be a smooth transition from building the Dreadnoughts to that of the successor to he Astutes, piggy backing as much technology as possible from the former to keep costs to a minimum and ideally including something like the Virginia Payload Module to future proof the vessels to some extent. The hard lessons learned from the astute programme must not be forgotten and serious work should be starting now on the design on the next SSN.

Why is the next SSN a not a reverse of the Valiant/Resolution fix. Just build Dreadnoughts without the vertical tubes? Or even leave one 4 tube vertical section to allow for VLS? If you want more SSNs the you could speed up the Dreadnought build program and build "Dreadnought" number 4 as an SSN while extending the programe to 8(?) hulls, with 4, 6, 7 and 8 being SSNs.

I don't think that Dreadnought-class can be easily converted into a SSN.

Halidon wrote:Is positively pork compared to a 774, but she's quite fast.

Russian and French "shapes" are also such; the noise argument (which I put forward, but with a v loose "grounding" I must admit) is a separate one.
- the H I Sutton article (was linked above) contains a nice graphic for shapes & sizes

Old RN wrote:could speed up the Dreadnought build program and build "Dreadnought" number 4 as an SSN while extending the programe

An excellent idea
- the designers will just have to test the speed and flow noise angles to it
- we can only (barely!) afford one military reactor type. Ideally the hunter-killers and boomers would use different types (different grades of fuel, too... which is the underlying argument for a different reactor design)

Isn't the goal to have a common reactor that lasts the life of the Submarine? Also having the quietness of a Boomer is not all that of a bad thing for a Hunter Killer as long as it can speed up when needed. Maybe they should start the design process with taking a Dreadnought and removing the Common Missile Compartment containing section and move forward from there.

abc123 wrote:I don't think that Dreadnought-class can be easily converted into a SSN.

Well, the front half of it is basically an Astute... gotta be helpful.

Going back to the Astutes. I notice HMS Audacious hasn't left Barrow as it should have done this year. It's been around 18 months since she hit the water. I believe the previous one 'Artful' left after around 15 months in the water. I can see the build schedule going back even further. It seems pretty poor that only 3 of the 7 are in service so far. I can imagine when boat 7 enters service her technology will be becoming obsolete.

Old RN wrote:leave one 4 tube vertical section to allow for VLS

In a minority of one I’m sure, but perhaps just build a single class of say 12 Hybrid SSN/SSBNs (replacing both the Boomers and Astutes) all with just 4 tubes. With the advent of BDM and Russia proliferating its capability across multiple platforms then sticking to the same seems SSBN only model seems dated.

Using the VPM does give some options, since the basic structure, apparently, is the same missile tube as used in the CMC, meaning that you have the possibility of fitting either 4 SLBMs or 28 conventional missiles into an identically-sized four-tube hull section. Simply for port access reasons, I would differentiate the two classes (many countries won't allow nuclear armed subs into their territorial waters), but building all subs to a common design and simply changing the launch system may have some advantages (and would allow the fall-back of nuclear-armed cruise missiles if that ever became a "thing" again)

Rambo wrote:the previous one 'Artful' left after around 15 months in the water. I can see the build schedule going back even further. It seems pretty poor that only 3 of the 7 are in service so far.

I don't know how much time to allow for "trials" but officially the gap between decommissioning a "T" and getting an operational "A" in its stead is... a year!

Gabriele wrote:Well, the front half of it is basically an Astute... gotta be helpful.

I think we can see a pattern emerging, the boomers introduce new propulsion (back end), and the hunters introduce new sonar (front end).

Are not the trident tubes to long to go in an astute size hull ? but it would be a good idea if we could build 3 x SSBN with 12 tubes then maybe as said before 8 x shorter SSN versions with only 4 x tubes to accommodate trident if needed, but normaly would carry cruise missiles or even UAV's or whatever comes into being...

I'm sure if the anti-nuclear lobby got wind of it they would try to say that there is a massive increase in ICBM capability....

It is, we should not be advocating more ICBMs.

serge750 wrote:Are not the trident tubes to long to go in an astute size hull ?

The Virginia Payload Tubes in the bow of Block III onward 774s, and the tubes in a Virginia Payload Module for Block V, are shorter than a full Trident tube. Even if the next generation of SSNs grow to share hull diameter with SSBNs, I would expect them to have shorter vertical tubes. For one, it would allow them to fit with a miminal fairing which benefits flow noise and speed concerns. For two, it would allow them to avoid arms treaty concerns about their use with the current Trident.

Latest edition of Warship World has a good article on the Silent Service. One suggestion is that with increased Russian activity and size of thier fleet analysts are looking at options to operate RN SSNs from European (Norwegian) ports. But given the dislike of nuclear power, there is a question whether the RN should look a buying some SSKs.

Must admit I’ve always thought that more SSNs would be a better solution, but given limitations on production as the focus turns to the SSBNs, perhaps a small 3-4 SSK fleet might be a good idea for UK / North Atlantic waters. Budget would need to be found from somewhere, but perhaps a better spend than the T31e.

IF we went down the SSK route, and Barrow being occupied with the Dreadnought work, would we go oversea to purchase such vessels also factoring in that we haven't build conventional submarines for how long.

Personally no, I think smaller unmanned submarines will be strategic assets of the future for sea denial. Keep the SSNs for CBG and global submarine ops but shorter range battery subs for UK EEZ and North Atlantic Control.

What's the delay with Audacious?

Repulse wrote:perhaps a small 3-4 SSK fleet might be a good idea for UK / North Atlantic waters.

Agreed but I think I would be a bit more ambitious. Maybe build 4 for UK waters and 2 for operations in the Med, forward based in Gibraltar. Also leave an option open for another 2 just in case things heat up in the South Atlantic.

Repulse wrote:Budget would need to be found from somewhere, but perhaps a better spend than the T31e.

It's a juggling act. The T31 budget might stretch to 4 very small SSK's, just. I think for it to be a realistic proposition new money would have to be secured. It really should be as a lack of SSN numbers is one of the biggest problems RN currently has in my opinion.

Lord Jim wrote:IF we went down the SSK route, and Barrow being occupied with the Dreadnought work, would we go oversea to purchase such vessels also factoring in that we haven't build conventional submarines for how long.

Definitely not but I would bring in a partner to try to keep costs under control and invest further in Barrow to make sure they are UK built. Personally I would avoid the French/Germans and go straight to SAAB. The Gotland replacement, the A26, looks like it has lots of potential.
The modular design is certainly innovative. The VLS module incorporating up 18 TLAM's would be a useful capability for any future RN SSK's operating in the Med but totally unnecessary for ops in UK waters. This versatility would be a big plus.

If a joint project with SAAB couldn't be secured another possible partner could be Japan.

The incorporation of Lithium Ion battery technology makes the Japanese Soryu class an attractive option.

http://www.navyrecognition.com/index.ph ... jmsdf.html

Of course, in an ideal world we would just build more Astute's

Poiuytrewq wrote:The T31 budget might stretch to 4 very small SSK's

Personally would be okay with that - thier primary purpose would be Sea Denial and ASW, leave the rest to the SSNs. Must admit have always thought if something a similar size of the KSS-500A would be a good fit, operating from shore bases but also larger transport ships.

We cannot spend anymore of the defence budget on submarines, it already consumes the equivalent to the entire budget for all combat aircraft, all surface vessels and all helicopters combined!.

The move to non nuclear propulsion for the astute replacement program maybe we’re it’s headed..

SW1, given that the majority of the submarine budget goes towards CASD, I don’t think it’s a fair comparison.