Current & Future Escorts - General Discussion

[Lord Jim]

Would the Mission Bay(s) on the T-31 be able to handle unmanned craft able to carry out the ASW detection role, possible operating as a pair with one as "Pinger" and one as "Listener", with the ships Helicopter being the "Shooter". The former two would be a longer range evolution of the "Troike" Remote Mine Hunting System used by the German Navy, hunting submarines in shallow waters as opposed to mines.

[donald_of_tokyo]

That is why I enjoy discussing things with you so much Donald-san

Thanks...

Doubling the "ping" DOES double the echo.

To double the amount of energy the target receives, the ping must be made 8 times more powerful. Or in other words, doubling the ping will result in an increase of energy at the target of the cube root of 2 (approx 1.3)

This is not correct. Signal is a function of input-pulse power A, and geometry effect (such as distance D).

S = F(A, D, ...).

Distance dependence is, as you said, not linear. The signal reaching the enemy SSK is proportional to 1/D^2 , and then reflected signal to reach the frigate decreases as 1/D^2 . So, final signal is proportional to 1/D^4 .

On the other hand, dependency to input power A is linear (in other words, S = F(A, D, ...) = A x F(D, ...) ). If you put twice a power in your ping, you get twice a power in the bounced-back signal. Just imagine you are speaking to a wall. Your voice reflects from the wall. If you speak with twice stronger voice, what you hear is also twice stronger. This is exactly what a sonar is doing.

(HMS will be) No not that cheap but not that expensive either. The design is supposed to have the ability to fit a hull sonar at a later date according the the RFI. I assume that would imply the space & power for computers/consoles would also be there. Ships complement might have to go up by a couple or 3. Don't forget sonars have utility other than for ASW.

No objection. My point is, ASW capability of hull mounted sonar might be dominated by the ASW analysis system (modern signal processing is very powerful but expensive), and its cost, and not the sonar itself (of course, hardware limit of the sonar surely exists). Using sonar for "other tasks" will be easy (depends on for what), but to hunt a SSK, HMS is deemed to be not powerful enough by all means even in 1990. This is why VDS and TASS, LFAS comes out.

Then, in 2020s, vastly improved signal processing will be changing the issue, and HMS might be not so powerless, but that means it is the analysis system which is the key, not the sonar itself. Space, weight, cabling is OK for Arrowhead140 (or all the other T31 contenders), as it is required as FTR. But, it does not mean it is cheap.

Another way to go is to use "shallow water" ASW system, such as SS2030 by Kongsberg (*1). With relatively high frequency = good resolution AND lower natural and ship-originating noise (stronger below ~2 kHz), but with significant power dumping in water and thus shorter range, it is good at short range and very shallow water. But this means the frigate is always within short range of enemy SSK. Even with good ship-torpedo defense system (decoy), ship maneuver is very important. Thus, large hull of Arrowhead 140 is not good at it and small ship is better.

Would the Mission Bay(s) on the T-31 be able to handle unmanned craft able to carry out the ASW detection role, possible operating as a pair with one as "Pinger" and one as "Listener", with the ships Helicopter being the "Shooter". The former two would be a longer range evolution of the "Troike" Remote Mine Hunting System used by the German Navy, hunting submarines in shallow waters as opposed to mines.

In this regards, USV/UUVs equipped with sonars is promising, as Lord Jim-san says. But, Arrowhead 140's boat alcove (as currently shown) cannot support 12m class USVs (Elbit SeaGull, ATLAS ARCIMS (*2), and Thales' USV, US Fleet-class USV), which is becoming the standard. This is bad. I personally think re-designing the Arrowhead 140's mid-ship boat-handling system is very very critical. No need for Mk.41 VLS. Even the 12-CAMM can be moved elsewhere. But, having a simple and large mission deck (open) or mission bay (enclosed) will be more important. If with a mission bay common in size with T26, any USV/UUV based future systems will be much more easy to be installed fleet-wide in RN, as a whole (*3).

*1: https://www.kongsberg.com/globalassets/ ... ar-ss-2030

*2: ARCIMS from Atlas.
https://www.atlas-ems.de/fileadmin/user ... online.pdf
https://www.atlas-elektronik.com/soluti ... rcims.html

There is an ASW option in the latter site.

*3: M-CUBE MCM system by Thales. https://www.thalesgroup.com/en/worldwid ... ent-system

It is can be integrated on TACTICOS CMS (Arrowhead 140's CMS).

[Tempest414]

The thing with A-140 /type 31 is the Iver Huitfeldt class is

A) Fitted with a hull mounted sonar
B) Is being fitted with a towed array sonar starting now

this mean the RN can see how this hull engines and prop setup works with hull mounted and towed sonars and compare it against both Type 23 and Type 45 to see where it fits. With this being said and what has been talked about i.e maybe A-140 getting 5 bladed props instead of the 4 bladed units on the IH class this work seems to have started and I think Babcock and the RN are pushing hard to reduce noise for a sonar

[Tempest414]

In this regards, USV/UUVs equipped with sonars is promising, as Lord Jim-san says. But, Arrowhead 140's boat alcove (as currently shown) cannot support 12m class USVs (Elbit SeaGull, ATLAS ARCIMS (*2), and Thales' USV, US Fleet-class USV), which is becoming the standard. This is bad. I personally think re-designing the Arrowhead 140's mid-ship boat-handling system is very very critical. No need for Mk.41 VLS. Even the 12-CAMM can be moved elsewhere. But, having a simple and large mission deck (open) or mission bay (enclosed) will be more important. If with a mission bay common in size with T26, any USV/UUV based future systems will be much more easy to be installed fleet-wide in RN, as a whole (*3).

So a bit of fantasy here but lets say we move some kit around on the A-140 to make a working deck. For me maybe we could start by moving the forward and rear 40mm turrets to each side of the hangar next fit 6 or 9 ExLS cells where the forward 40mm was to allow 24 or 36 CAMM then push any SSGW launchers out to the side of the old weapons deck and fit a 26 ton crane between them this should leave enough room for 4 USV's. Plus if we have moved the two 40mm guns each side of the hangar we could put a Phalanx on top of the hangar

of course the the other way is to build in a slip way from the mission bay under the flight deck which could hold 4 USV'a as the ARCIMS is the same size a 20 foot shipping container

[donald_of_tokyo]

So a bit of fantasy here but lets say we move some kit around on the A-140 to make a working deck. For me maybe we could start by moving the forward and rear 40mm turrets to each side of the hangar next fit 6 or 9 ExLS cells where the forward 40mm was to allow 24 or 36 CAMM then push any SSGW launchers out to the side of the old weapons deck and fit a 26 ton crane between them this should leave enough room for 4 USV's. Plus if we have moved the two 40mm guns each side of the hangar we could put a Phalanx on top of the hangar

Interesting.
But, I think "removing" the forward 40 mm gun (the 57 mm gun can do), and moving the 12-cell CAMM there is good enough, with minimal design change.

of course the the other way is to build in a slip way from the mission bay under the flight deck which could hold 4 USV'a as the ARCIMS is the same size a 20 foot shipping container

Uhh, no. 20ft container is 6x2.5x2.5 m3. ACRIMS is 11.3x3.4x3.7 m3. (https://www.atlas-ems.de/fileadmin/user ... online.pdf)

[Ron5]

This is not correct. Signal is a function of input-pulse power A, and geometry effect (such as distance D).

S = F(A, D, ...).

Distance dependence is, as you said, not linear. The signal reaching the enemy SSK is proportional to 1/D^2 , and then reflected signal to reach the frigate decreases as 1/D^2 . So, final signal is proportional to 1/D^4 .

On the other hand, dependency to input power A is linear (in other words, S = F(A, D, ...) = A x F(D, ...) ). If you put twice a power in your ping, you get twice a power in the bounced-back signal. Just imagine you are speaking to a wall. Your voice reflects from the wall. If you speak with twice stronger voice, what you hear is also twice stronger. This is exactly what a sonar is doing.

I won't pretend to understand all this! But I'm guessing you are saying if you double the ping in the exact direction of the target, its echo will also be doubled. But pings are three dimensional so to double the power in one direction, the total ping must be increased 8 fold.

This is why VDS and TASS, LFAS comes out.

I think towed arrays were developed for two main reasons: to get the sonar away from the noise of the host ship and to place the sonar beneath the thermocline.

I personally think re-designing the Arrowhead 140's mid-ship boat-handling system is very very critical. No need for Mk.41 VLS. Even the 12-CAMM can be moved elsewhere. But, having a simple and large mission deck (open) or mission bay (enclosed) will be more important. If with a mission bay common in size with T26, any USV/UUV based future systems will be much more easy to be installed fleet-wide in RN, as a whole

I agree. A quick look at the A140 design makes me think that the deck beneath the weapons deck is relatively empty and maybe could be cleared side to side to enable a T26 type mission deck with doors either side. I think that is what you are suggesting. Good idea.

[Ron5]

In this regards, USV/UUVs equipped with sonars is promising, as Lord Jim-san says. But, Arrowhead 140's boat alcove (as currently shown) cannot support 12m class USVs (Elbit SeaGull, ATLAS ARCIMS (*2), and Thales' USV, US Fleet-class USV), which is becoming the standard. This is bad. I personally think re-designing the Arrowhead 140's mid-ship boat-handling system is very very critical. No need for Mk.41 VLS. Even the 12-CAMM can be moved elsewhere. But, having a simple and large mission deck (open) or mission bay (enclosed) will be more important. If with a mission bay common in size with T26, any USV/UUV based future systems will be much more easy to be installed fleet-wide in RN, as a whole (*3).

So a bit of fantasy here but lets say we move some kit around on the A-140 to make a working deck. For me maybe we could start by moving the forward and rear 40mm turrets to each side of the hangar next fit 6 or 9 ExLS cells where the forward 40mm was to allow 24 or 36 CAMM then push any SSGW launchers out to the side of the old weapons deck and fit a 26 ton crane between them this should leave enough room for 4 USV's. Plus if we have moved the two 40mm guns each side of the hangar we could put a Phalanx on top of the hangar

of course the the other way is to build in a slip way from the mission bay under the flight deck which could hold 4 USV'a as the ARCIMS is the same size a 20 foot shipping container

Yes, your first suggestion is just the ticket.

Your second, not so much. I suspect the space under the flight deck is pretty uninviting and just meant as a hold, and rear slipways are kind of unusable in any kind of sea state apart from a flat calm. Midships davits are much more usable.

[Jensy]

I think the suggestion of converting the amidships space into a mission bay is excellent. However I can't see there being any capacity for redesign of the ship. Especially if one believe Francis Tusa's statments to the Defence Select Committee yesterday: https://parliamentlive.tv/Event/Index/6 ... 2cf47b3a04



If I was being mean, I'd say the guy who was adamant that Type 26 had no chance of winning in either Canada or Oz should be taken with a pinch of salt...

Yet it is clear that the Type 31 is at the limit of what the government is currently willing to spend, which is a shame really as I daresay a lot more ship could be delivered for not that much more investment (as the conversation on sonar suggests).

Unfortunately the only scope for an improved Type 31 would appear to be fewer or a less capable Batch 2 Type 26. An idea so illogical and counter-intuitive to the history of both programmes that it must be under serious consideration by the MoD....

[Lord Jim]

They really need to give these people some decent microphones rather than rely on the inbuilt ones in their Laptops!

[shark bait]

So a bit of fantasy here but lets say we move some kit around on the A-140 to make a working deck.

Fixes what I always had down as a bit shortcoming for all the T31 proposals. Very little is interoperable between the different frigates. At a minimum the stuff developed for the T26 mission bay should also work on the T31.

[serge750]

I still hope that we can have a modified ( as you say a common work bay, HMS etc ) better equipped batch 2 version & sell off cheaply the first batch if there is a buyer, would NZ want some nearly new "patrol frigates" for 150m a piece?, just accept that they had work to keep people employed & keep their skills current.

[Tempest414]

So a bit of fantasy here but lets say we move some kit around on the A-140 to make a working deck. For me maybe we could start by moving the forward and rear 40mm turrets to each side of the hangar next fit 6 or 9 ExLS cells where the forward 40mm was to allow 24 or 36 CAMM then push any SSGW launchers out to the side of the old weapons deck and fit a 26 ton crane between them this should leave enough room for 4 USV's. Plus if we have moved the two 40mm guns each side of the hangar we could put a Phalanx on top of the hangar

There is another way which means fitting kit already in service so as above remove the two 40mm and replace with two 30mm one each side of the hangar again as above move the CAMM forward to where the 40mm was next fit a Phalanx from the pool on top of the Hangar and once again as above fit a Crane on the old weapons deck and make it a working deck giving the ship 4 x boat bays and a working deck.

As for the removed 40mm's if they are not ordered take the money and put it towards a HMS or more CAMM if they have been ordered fit one each on the B2 Rivers and 2 on each Carrier leaving 1 as a shore based training unit or pool replacement unit there by spreading the love and maybe making the fleet more balanced

[Lord Jim]

The choice of the 40mm for the T-31 has been a strange choice from my point of view. Introducing two new calibres of weapon when the existing DS30 would do as good as job and we will have a number of these available as the T-23s retire. Then of course there would also have been the choice of fitting the LMM launchers to the DS30.

[ArmChairCivvy]

The choice of the 40mm for the T-31 has been a strange choice from my point of view. Introducing two new calibres of weapon when the existing DS30 would do as good as job

The new 40mm and DS30 are from different centuries... and are oceans apart in all-round capability

[jedibeeftrix]

The choice of the 40mm for the T-31 has been a strange choice from my point of view. Introducing two new calibres of weapon when the existing DS30 would do as good as job and we will have a number of these available as the T-23s retire. Then of course there would also have been the choice of fitting the LMM launchers to the DS30.

Quoting you, but the sense i get widely is that no one is really enthused by them.

Why?

To me it seems like a very positive improvement:
Useful on t31 as a goalkeeper/chokepoint frigate
Useful on river B2's as a miminal form of self defence
Useful on the frigates as an upgrade to the old 30's.
And by the time they are this common, you might even find it cost effective to use them in RFA boats...

Yes, we could delete them, but then we're back to the old british game of fitted for but never with.

[S M H]

The new 40mm and DS30 are from different centuries... and are oceans apart in all-round capability

I watched the problems caused with the 76mm. The treasury shenanigan's. Suggesting it as a cost saving fitting it to then redesigned Type 23 frigates as replacement for the venerable 4.5 gun. The use of requirements to exclude it. This at the detriment of using it as main gun on patrol craft. The Castles were intended to have them and were fitted for but not completed with. The peacock's were ordinally going to be fitted with Breada 40 h twin mountings aft. The were deleted from the completed hulls. Though the rear 40mm was a requirement on the Hong Kong tons. Maybe this time the 40 mm will get into service. Then if possible fitted to patrol craft if we base one east of Suez. Fitting it the main armament of the M.C.M replacement. Therefore releasing 30 mm. to be fitted on the gulf type 31 on the sides of the hangar. Then fitted to the rivers. As done with the amazon's when stored in Ramsden dock at Barrow in Furness. But this is all wishful thinking if they don't end up fitted on completion of the type 31s. on cost savings We should not fall short time thinking that has bedevilled introduction of a new weapons systems.

[Jake1992]

The new 40mm and DS30 are from different centuries... and are oceans apart in all-round capability

I watched the problems caused with the 76mm. The treasury shenanigan's. Suggesting it as a cost saving fitting it to then redesigned Type 23 frigates as replacement for the venerable 4.5 gun. The use of requirements to exclude it. This at the detriment of using it as main gun on patrol craft. The Castles were intended to have them and were fitted for but not completed with. The peacock's were ordinally going to be fitted with Breada 40 h twin mountings aft. The were deleted from the completed hulls. Though the rear 40mm was a requirement on the Hong Kong tons. Maybe this time the 40 mm will get into service. Then if possible fitted to patrol craft if we base one east of Suez. Fitting it the main armament of the M.C.M replacement. Therefore releasing 30 mm. to be fitted on the gulf type 31 on the sides of the hangar. Then fitted to the rivers. As done with the amazon's when stored in Ramsden dock at Barrow in Furness. But this is all wishful thinking if they don't end up fitted on completion of the type 31s. on cost savings We should not fall short time thinking that has bedevilled introduction of a new weapons systems.

It’s daft to keep both the 30mm and 40mm in service together for the longer term, it’ll mean we’ll have 25mm ( phalanxe ) 30mm, 40mm, 57mm, 4.5inch, 5inch all in service for the long term and not just transition.

[S M H]

It’s daft to keep both the 30mm and 40mm in service together for the longer term, it’ll mean we’ll have 25mm ( phalanxe ) 30mm, 40mm, 57mm, 4.5inch, 5inch all in service for the long term and not just transition.

The 40mm 30 mm over lap but thinking beyond the short term. When the type 45 get replaced after the type 26 and introduction of the 31s the 4.5 will be gone they may adopt the 40 mm for the 45 replacement . Had gone for 5 inch instead of trying to use the existing 4.5 up gunned to use two part explosive and shell in a attempt to have a common supply chain. All at the altar of efficiency and paying for the R& D.The 4.5 would never have been fitted to the type 45s. The requirement for main armament on the M.C.M requirement will require a range more than the present 30mm and a longer engagement as operational tactics that they need to defend evolve. The transition will be long due to our poor prior procurement.

[Lord Jim]

The new 40mm and DS30 are from different centuries... and are oceans apart in all-round capability

As I said it surprised me when we have a situation where every penny counts with the T-31e, that we go for a totally new gun, which in order to get the most from it requires additional expense in the form of sensor fused ammunition and so on, where as the DS30 could have been supplies as Government Furnished Equipment. I agree that fully tooled up the Latest Bofors 40mm provides a much greater capability but at a cost.

[serge750]

Yes does seem strange as they are watching every penny & could of added the LMM at a later date,

Perhaps they were going on looks as the 40mm is more aesthetically pleasing or maybe they got a discount on the 40mm,

Would the 40mm have a better development path in the future ?

[Tempest414]

The 40mm Mk4 is a better all round gun system and some may see the 57mm and 40mm with 3P ammo as a strong option which it is. The 30mm is also a good weapon but I think the RN are looking to the future and having both the 57mm and the 40mm gives them options which until now they have not really had. I feel the only reason the B2 Rivers have a 30mm is it was the next weapon in service below the 4.5" gun and there for the only option on a ship built under TOBA. Having both the 57mm and 40mm will give them a option on how to upgrade the weapons package on the B2's and future classes like MH(P)C

[donald_of_tokyo]

57mm 3P has a good future with significant amount of investments from US and other nations. But, adding a 40 mm 3P is not comfortable for me, actually. Too much overlap with BOTH 30mm (in low end) and 57 mm (in high end).

A 30mm gun and a 40mm Bofors 3P differs a lot in capability. But, its cost differs a lot, as well.

I'm not sure what will come after 30mm gun. In many low-end applications, a 40mm gun is too much and too expensive (turret cost, man-power, ammo-cost and maintenance load). So a cheap gun is anyway needed. See HMS Echo/Enterprise, EEZ patrol OPVs, and RFA vessels (when deployed to peaceful region). Going back to the old 20mm guns?

In addition, a 30mm turret added with LMM rounds can cover most, but NOT all, of the 40mm 3P tasks. Again, big overlap. Very unpleasant. So, for me, when thinking about adding something to T31e, the two 40mm guns comes always as the top priority to cut.

[Ron5]

The choice of the 40mm for the T-31 has been a strange choice from my point of view. Introducing two new calibres of weapon when the existing DS30 would do as good as job

The new 40mm and DS30 are from different centuries... and are oceans apart in all-round capability

The Bofors gun was originally designed in the 1930's and the Bushmaster chain gun in the DS30B in the 1980's. So yes, the DS30B is much younger.

Two points about the Bushmaster: firstly, programmable 30mm ammunition is available and can perform all the same functions as the Bofors 3P. Secondly, the Bushmaster is easily upgradable to 40mm (a handful of parts need to be exchanged) and ATK is developing a full range of ammunition for that conversion including programmable. MSI advertises that its mount can handle the 40mm.

The Bushmaster supports dual ammunition feed with almost instantaneous switch over. So regular HE could be supported alongside the more expensive programmable air burst. I do not know if the MSI mounts supports the dual feed, the mounts fitted to the Type 23's do not appear to.

The MSI mounting fitted with the 30/40mm Bushmaster and LMM, with remote EO sensor & control seems to be to be a very capable system that's available at reasonable cost. Made in the UK too with a good record of exports.

The theory on the type 31's was that the builder would decide armament & equipment and would present the package to the MoD. Only CAMM was mandated. So it was Babcock's/Thales that decided the Bofors gun, not the RN. Of course in practice, I doubt if it was this black and white.

[ArmChairCivvy]

The new 40mm

... and the operative word is

I do not know if the MSI mounts supports the dual feed, the mounts fitted to the Type 23's do not appear to.

In practice their function is anti-surface (only); helos , why not, but would any ever venture within range?
- however, USN has had a great experience with the new round (for holing below the waterline). Don't know how that compares with the normal AP, and would a dual feed be useful or just a luxury (putting a lot of AB down the range, towards zig-zagging speed boats must be be more fun than a turkey shoot, though)

[Ron5]

The new 40mm

... and the operative word is

I do not know if the MSI mounts supports the dual feed, the mounts fitted to the Type 23's do not appear to.

In practice their function is anti-surface (only); helos , why not, but would any ever venture within range?
- however, USN has had a great experience with the new round (for holing below the waterline). Don't know how that compares with the normal AP, and would a dual feed be useful or just a luxury (putting a lot of AB down the range, towards zig-zagging speed boats must be be more fun than a turkey shoot, though)

The gun & mechanism in the Bofors Mk IV is not new by any means.

Yes, air burst is very useful in a maritime environment. Well that's what Bofors says when its trying to sell its gun. There's video on YouTube that shows it in action.

Pretty much all of the advantages of the Bofors weapon is due to its 3P ammunition which is very good but the rest of the world is not just sitting around, they're catching/caught up. Esp ATK which pretty much has the western 30mm market sown up.