UK Defence Forum

Since when is a type 31 have a much higher cost than 250-300m pounds?

I wouldn’t hold out much hope that a river derived ship with a beam of 13m will be loading offloading 25 tonne assault craft or unmanned systems in any sort of safe way

When it includes all build and support costs, which makes it closer to £400mn.

The first three B2 River class were £350mn including support costs (and a good dose of cost to develop new design techniques and keep a workforce busy for a period of time).

It is perfectly possible to get a capable platform for the role being described at half a T31.

Repulse wrote: ↑11 Mar 2023, 10:17 When it includes all build and support costs, which makes it closer to £400mn.

The first three B2 River class were £350mn including support costs (and a good dose of cost to develop new design techniques and keep a workforce busy for a period of time).

It is perfectly possible to get a capable platform for the role being described at half a T31.

The contract with Babcock is for 1.25b for 5 ships. There is additional contingency and cost to the RN from commissioning a new vessel type into service and government furnished equipment that adds the rest.

No it isn’t unless you’re simply buying a HMS protector type vessel. If you start adding thing that mean the ships will be shot at then quickly head away from civil or offshore patrol vessels and back to a warship eg a type 31.

SW1 wrote: ↑11 Mar 2023, 10:35 No it isn’t unless you’re simply buying a HMS protector type vessel. If you start adding thing that mean the ships will be shot at then quickly head away from civil or offshore patrol vessels and back to a warship eg a type 31.

So there is nothing between a civilian built ice Patrol Ship and a T31 - I don’t even know where to start

SW1 wrote: ↑11 Mar 2023, 09:56 Since when is a type 31 have a much higher cost than 250-300m pounds?

I wouldn’t hold out much hope that a river derived ship with a beam of 13m will be loading offloading 25 tonne assault craft or unmanned systems in any sort of safe way

Sorry, respectfully, too dismissive IMO.

Much of the £250m-£300m suggested was for the XLUUVs, heavy lift UAVs and containerised Captas.

If built most efficiently I wouldn’t expect a batch of five 111m RB3s to cost much more than £800m as long as the weapons and sensors were kept at an OPV level and the working deck remained unenclosed.

As for safe unloading at sea: The RB2 has a beam of 13.5m and has no difficulty unloading a 16t container. The 111m version would also likely have a 13.5m beam and a displacement of around 2400t. The CB90 weights around 15t standard load and 20t full load. It is entirely possible for RN to commission a fast assault craft that fits safely within these parameters. Ditto for a RN XLUUV.

Repulse wrote: ↑11 Mar 2023, 09:53

Poiuytrewq wrote: ↑11 Mar 2023, 09:10 However the capability is worth exploring.

Absolutely, and if the ambition is there then the future (and unknown) design for the four LSV could be that opportunity.

Perhaps but there is virtually no info on these LSVs currently. I am expecting commercial PSVs being converted for the role by covering the working deck and adding side hatches plus stern and gantry cranes. Cheap and cheerful should be the order of the day and I am not sure a Patrol range/endurance is even necessary.

I’m sure there will be the usual big is beautiful discussions, but a ship of a similar size to what you suggest is the right answer to the UK’s Littoral blind spot when combined with unmanned ASW/MCM systems and optionally the ability to act as a platform for sub company level RM operations.

The 111m RB3 would do an admirable job in the Littoral but I think better options exist even for sub £200m vessels.

The 111m RB3 and the T31 are too similar to be a sensible direction of travel. Add another five T32 hybrid Frigates and the entire fleet balance at the patrol end would look like a complete mess.

If current planning adapts and the T32s are cancelled plus the T31s are upgraded from a Patrol to a GP standard then the RB3 becomes a serious proposition. Even then better options exist but the RB3 would not be a bad option.

Poiuytrewq wrote: ↑11 Mar 2023, 11:23

SW1 wrote: ↑11 Mar 2023, 09:56 Since when is a type 31 have a much higher cost than 250-300m pounds?

I wouldn’t hold out much hope that a river derived ship with a beam of 13m will be loading offloading 25 tonne assault craft or unmanned systems in any sort of safe way

Sorry, respectfully, too dismissive IMO.

Much of the £250m-£300m suggested was for the XLUUVs, heavy lift UAVs and containerised Captas.

If built most efficiently I wouldn’t expect a batch of five 111m RB3s to cost much more than £800m as long as the weapons and sensors were kept at an OPV level and the working deck remained unenclosed.

As for safe unloading at sea: The RB2 has a beam of 13.5m and has no difficulty unloading a 16t container. The 111m version would also likely have a 13.5m beam and a displacement of around 2400t. The CB90 weights around 15t standard load and 20t full load. It is entirely possible for RN to commission a fast assault craft that fits safely within these parameters. Ditto for a RN XLUUV.

It’s doesn’t unload a container at sea. If you look at all the vessels that do offload heavy systems at sea they are all in 18m beam region specifically for stability.

Repulse wrote: ↑11 Mar 2023, 11:18

SW1 wrote: ↑11 Mar 2023, 10:35 No it isn’t unless you’re simply buying a HMS protector type vessel. If you start adding thing that mean the ships will be shot at then quickly head away from civil or offshore patrol vessels and back to a warship eg a type 31.

So there is nothing between a civilian built ice Patrol Ship and a T31 - I don’t even know where to start

If your are starting to expect vessels to be shot at and adding capabilities that by definition imply that and sending them unescorted to parts of the world where that could happen then yes they need to be built with the redundancy, stability and damage control specifications of a warship rather than civil or offshore patrol vessel construct that do fisheries protection and environmental enforcement.

SW1 wrote: ↑11 Mar 2023, 11:53 It’s doesn’t unload a container at sea. If you look at all the vessels that do offload heavy systems at sea they are all in 18m beam region specifically for stability.

Completely agree but it’s a compromise.

If RN commission a vessel with an 18m beam for stability when launching and recovering off board systems then it will struggle to achieve 25knts like the RB2s. A 111m RB3 with the same propulsion setup would likely achieve 26/27knts. That’s the compromise.

If building to purely commercial standards then widening the beam and upgrading the propulsion system to achieve around 24/25knts should be easily achievable but the vessel will burn a lot more diesel and will likely be operated by the RFA rather than RN.

Although sub-optimal a 111m RB3 could launch and recover a fast assault craft or XLUUV especially in the Littoral in a moderate sea state. The Albions are the only other RN vessel with that capability and the classes are hardly comparable.

Attempting to build a 130m class vessel with a 18m+ beam to naval standards optimised for the Littoral basically results in a T32 and the £500m price tag that goes with it. Even Absalon cannot launch and recover a CB90 or hit 25knts without adaption.

Much better to use inexpensive, simple vessels to perform these tasks in low threat areas and simply escort them in higher threat areas.

Just my opinion.

SW1 wrote: ↑11 Mar 2023, 12:01 If your are starting to expect vessels to be shot at and adding capabilities that by definition imply that and sending them unescorted to parts of the world where that could happen then yes they need to be built with the redundancy, stability and damage control specifications of a warship rather than civil or offshore patrol vessel construct that do fisheries protection and environmental enforcement.

Who said they would be unescorted in a high threat environment? Once again, smaller ships can have much higher damage control than a civil or standard OPV, such as the B2 Rivers.

It feels your vision for the surface fleet is 24 large warships and nothing else, with at best the ability to build a new one every year. It goes against centuries of wisdom of having balanced fleets with tiers of capabilities and numbers. Bonkers

Poiuytrewq wrote: ↑11 Mar 2023, 12:47

SW1 wrote: ↑11 Mar 2023, 11:53 It’s doesn’t unload a container at sea. If you look at all the vessels that do offload heavy systems at sea they are all in 18m beam region specifically for stability.

Completely agree but it’s a compromise.

If RN commission a vessel with an 18m beam for stability when launching and recovering off board systems then it will struggle to achieve 25knts like the RB2s. A 111m RB3 with the same propulsion setup would likely achieve 26/27knts. That’s the compromise.

If building to purely commercial standards then widening the beam and upgrading the propulsion system to achieve around 24/25knts should be easily achievable but the vessel will burn a lot more diesel and will likely be operated by the RFA rather than RN.

Although sub-optimal a 111m RB3 could launch and recover a fast assault craft or XLUUV especially in the Littoral in a moderate sea state. The Albions are the only other RN vessel with that capability and the classes are hardly comparable.

Attempting to build a 130m class vessel with a 18m+ beam to naval standards optimised for the Littoral basically results in a T32 and the £500m price tag that goes with it. Even Absalon cannot launch and recover a CB90 or hit 25knts without adaption.

Much better to use inexpensive, simple vessels to perform these tasks in low threat areas and simply escort them in higher threat areas.

Just my opinion.

Which is sort of my point. I don’t think it’s necessarily so much a compromise as I don’t think a ships with such a short beam is capable from a safety point of view of offloading those heavy weights at sea. if you want such things with the speed with the helicopter with all the rest you very quickly end up at a type 31 sized vessel.

If you are prepared to make the comprise that off board systems are the focus you end up with a Dutch mcm motherships or even an echo class size vessel or an HMS protector or rss Attenborough but the compromise is no helicopter and a more civil construction or indeed a royal fleet aux it most certainly is not a modified river.

Repulse wrote: ↑11 Mar 2023, 14:03

SW1 wrote: ↑11 Mar 2023, 12:01 If your are starting to expect vessels to be shot at and adding capabilities that by definition imply that and sending them unescorted to parts of the world where that could happen then yes they need to be built with the redundancy, stability and damage control specifications of a warship rather than civil or offshore patrol vessel construct that do fisheries protection and environmental enforcement.

Who said they would be unescorted in a high threat environment? Once again, smaller ships can have much higher damage control than a civil or standard OPV, such as the B2 Rivers.

It feels your vision for the surface fleet is 24 large warships and nothing else, with at best the ability to build a new one every year. It goes against centuries of wisdom of having balanced fleets with tiers of capabilities and numbers. Bonkers

It’s not even high threat it’s any threat, if you’re equipping it with modular systems to hunt ssks it certainly isn’t low threat. The navy class the rivers as opvs, the rivers have not been built or classified as anything more than that and I don’t believe the RN see them from a damage control perspective as anything more than that. You can build smaller ships to warship standards but they generally become expensive and cramped as you are attempting Swiss watch building.

For the escort fleet it would be not much beyond 18 tbh of which around 8/9 would be what you would class as very high end. My investment would be in crews, offboard systems/weapons and the ssn fleet. There is room for for HMS protector and vessels of a similar elk for survey/off board mcm systems in uk waters ect but largely more to the RFA than the RN. Basically offboard systems can be from an RFA/RN vessel or the shore.

I don’t think it does go against the wisdom of centuries, we have a surface fleet set against a certain priority ie NATO and in specific areas of interest to us in relation namely to trade/infrastructure protection. For high end peer naval warfare only the submarine will win out at containing China and Russia.

Repulse wrote: ↑11 Mar 2023, 10:17 When it includes all build and support costs, which makes it closer to £400mn.

The first three B2 River class were £350mn including support costs (and a good dose of cost to develop new design techniques and keep a workforce busy for a period of time).

It is perfectly possible to get a capable platform for the role being described at half a T31.

You cannot be seriously proposing trying to turn River B2 into type 31. 126 million for an OPV with no hangar and a 30m gun. By the time you’d put Camm reader and a couple of guns on it the price would be pretty much the same and you’ve still got a much less stable and survival platform. If you just want to launch drones I’d suggest purchase anither second hand PSV for 10-20 million

SD67 wrote: ↑11 Mar 2023, 17:42 You cannot be seriously proposing trying to turn River B2 into type 31.

No, I’m not.

SD67 wrote: ↑11 Mar 2023, 17:42 By the time you’d put Camm reader and a couple of guns on it the price would be pretty much the same

No, it wouldn’t

SW1 wrote: ↑11 Mar 2023, 17:21 For the escort fleet it would be not much beyond 18 tbh of which around 8/9 would be what you would class as very high end. My investment would be in crews, offboard systems/weapons and the ssn fleet. There is room for for HMS protector and vessels of a similar elk for survey/off board mcm systems in uk waters ect but largely more to the RFA than the RN. Basically offboard systems can be from an RFA/RN vessel or the shore.

I don’t think it does go against the wisdom of centuries, we have a surface fleet set against a certain priority ie NATO and in specific areas of interest to us in relation namely to trade/infrastructure protection. For high end peer naval warfare only the submarine will win out at containing China and Russia.

That means no CBGs and no independent LRGs and no forward basing. More SSNs would be great, but they can only ever be part of the puzzle.

Your ambition is limited to being a regional navy, I can accept that, but don’t agree with it.

Repulse wrote: ↑11 Mar 2023, 22:12

SW1 wrote: ↑11 Mar 2023, 17:21 For the escort fleet it would be not much beyond 18 tbh of which around 8/9 would be what you would class as very high end. My investment would be in crews, offboard systems/weapons and the ssn fleet. There is room for for HMS protector and vessels of a similar elk for survey/off board mcm systems in uk waters ect but largely more to the RFA than the RN. Basically offboard systems can be from an RFA/RN vessel or the shore.

I don’t think it does go against the wisdom of centuries, we have a surface fleet set against a certain priority ie NATO and in specific areas of interest to us in relation namely to trade/infrastructure protection. For high end peer naval warfare only the submarine will win out at containing China and Russia.

That means no CBGs and no independent LRGs and no forward basing. More SSNs would be great, but they can only ever be part of the puzzle.

Your ambition is limited to being a regional navy, I can accept that, but don’t agree with it.

My ambition is for a navy that defends our interests where they need defending.

It’s would be perfectly possible to form a battle group indeed two and fwd base ships from such a construct.

SW1 wrote: ↑11 Mar 2023, 22:42 My ambition is for a navy that defends our interests where they need defending.

It’s would be perfectly possible to form a battle group indeed two and fwd base ships from such a construct.

With 8/9 very high end (I assume these are T26 like vessels) and a similar number of cheaper T31 vessels, then effectively you will have 3 capable ships available at any point in time and another 3 that can do low end ops or need to be escorted themselves. Not enough for your objective.

CSGs are key to your ambition to “defend our interests where they need defending”, and they would be very exposed. You could do it with 18-19 T45s/T26s, but that’s exactly what you’ve argued against.

I’m also interested to note your comment:

SW1 wrote: ↑11 Mar 2023, 17:21Basically offboard systems can be from an RFA/RN vessel or the shore.

So this means you either believe RFAs can be better protected than something smaller than a T31, or that it’s ok they are targets?

Repulse wrote: ↑12 Mar 2023, 08:06

SW1 wrote: ↑11 Mar 2023, 22:42 My ambition is for a navy that defends our interests where they need defending.

It’s would be perfectly possible to form a battle group indeed two and fwd base ships from such a construct.

With 8/9 very high end (I assume these are T26 like vessels) and a similar number of cheaper T31 vessels, then effectively you will have 3 capable ships available at any point in time and another 3 that can do low end ops or need to be escorted themselves. Not enough for your objective.

CSGs are key to your ambition to “defend our interests where they need defending”, and they would be very exposed. You could do it with 18-19 T45s/T26s, but that’s exactly what you’ve argued against.

I’m also interested to note your comment:

SW1 wrote: ↑11 Mar 2023, 17:21Basically offboard systems can be from an RFA/RN vessel or the shore.

So this means you either believe RFAs can be better protected than something smaller than a T31, or that it’s ok they are targets?

The rule of 3s do not apply to the carrier or the lpd. If it’s good enough for them it’s gd enough for their escort. We would have a high/ low group similar to a US expeditionary strike group and principally assigned to nato.

HMS Montrose and now Lancaster has proven the concept of fwd deployed frigates as have many other navy’s doing similar. Ideally each of these ships would have a port and starboard crew arrangement. Type 31s DO NOT need something to escort them. They can be deployed for maritime security/escort and trade/infrastructure protection.

As we have seen they have purchased civil RFA crewed vessels for deployment of MCM and most likely hydrographic operations around the uk so that would continue or from shore. If they were required within the battlegroup the systems and crew would operate from ships within the group.

SW1 wrote: ↑12 Mar 2023, 09:33 The rule of 3s do not apply to the carrier or the lpd. If it’s good enough for them it’s gd enough for their escort. We would have a high/ low group similar to a US expeditionary strike group and principally assigned to nato.

HMS Montrose and now Lancaster has proven the concept of fwd deployed frigates as have many other navy’s doing similar. Ideally each of these ships would have a port and starboard crew arrangement. Type 31s DO NOT need something to escort them. They can be deployed for maritime security/escort and trade/infrastructure protection.

As we have seen they have purchased civil RFA crewed vessels for deployment of MCM and most likely hydrographic operations around the uk so that would continue or from shore. If they were required within the battlegroup the systems and crew would operate from ships within the group.

The rule of 3 is there to ensure that there are trained / worked up units ready for deployment - if you are accepting a lower level of readiness then I understand, but that means less ability to protect interests early.

The T31, as outlined in its requirements, is not meant to be a war fighting unit, it is there for lower level operations. It needs an escort in a high threat environment. Could it be upgraded to be a capable of operating in a high threat environment, quite possibly, but it will not be at the same level as a T26/T45, and it will cost and take time to ramp up - another delay when time is critical.

Your argument that an RFA can be protected as part of a CSG is true, but putting aside the fact that the vessels being discussed would struggle to keep up, the same can be said for the RN Sloops that we’ve been discussing. What’s more by using Sloops you would be able to have a response appropriate to the threat level, can conduct broader roles, have more ships so you can operate in more places, but also you aren’t trying to use the RFA as the RN on the cheap.

Repulse wrote: ↑12 Mar 2023, 10:07

SW1 wrote: ↑12 Mar 2023, 09:33 The rule of 3s do not apply to the carrier or the lpd. If it’s good enough for them it’s gd enough for their escort. We would have a high/ low group similar to a US expeditionary strike group and principally assigned to nato.

HMS Montrose and now Lancaster has proven the concept of fwd deployed frigates as have many other navy’s doing similar. Ideally each of these ships would have a port and starboard crew arrangement. Type 31s DO NOT need something to escort them. They can be deployed for maritime security/escort and trade/infrastructure protection.

As we have seen they have purchased civil RFA crewed vessels for deployment of MCM and most likely hydrographic operations around the uk so that would continue or from shore. If they were required within the battlegroup the systems and crew would operate from ships within the group.

The rule of 3 is there to ensure that there are trained / worked up units ready for deployment - if you are accepting a lower level of readiness then I understand, but that means less ability to protect interests early.

The T31, as outlined in its requirements, is not meant to be a war fighting unit, it is there for lower level operations. It needs an escort in a high threat environment. Could it be upgraded to be a capable of operating in a high threat environment, quite possibly, but it will not be at the same level as a T26/T45, and it will cost and take time to ramp up - another delay when time is critical.

Your argument that an RFA can be protected as part of a CSG is true, but putting aside the fact that the vessels being discussed would struggle to keep up, the same can be said for the RN Sloops that we’ve been discussing. What’s more by using Sloops you would be able to have a response appropriate to the threat level, can conduct broader roles, have more ships so you can operate in more places, but also you aren’t trying to use the RFA as the RN on the cheap.

There is only two carriers the escorts are on their workup cycle. This protects our interests within NATO area and is the surface combat fleet.


I don’t know how many time that type 31 myth needs busted.. The type 31 are fwd deployed protecting our interests primarily outside of the NATO area

I didn’t say the systems would be on the rfa operating around the U.K.whilst with the battlegroup. They would be operated from ships within the battlegroup. That might be the accompanying rfa tanker/stores ship it might be a frigate it might be a lpd. It most certainly won’t be a “sloop”

Just to be clear the 2 new off the self ships for the RFA will have crews of 24 RFA and 60 RN on them

For me as said time and time again we will need more patrol ships and we all ready have them in service or being built in the form of RB2 and Type 31 these ships are already capable of operating a lot of extra kit they just need to be a bit more fighty and we need 8 of each

RB2's could operate

Containerised UAV's
containerised or deck mounted GSDB
4 x ORC for raiding ( backed up by the UAV and Loiter weapons like Hero 120 for over watch )
4 x 9.5 m Unmanned Ribs capable of limited MCM and ASW or area control if fitted with 12.7mm or 40mm GMG
A re-enforced Platoon of RM

Type 31 could operate

Containerised TAS
deck mounted NSM & GSDB
OCR for raiding ( backed up by Wildcat , UAV , Hero 120 . NSM , GSDB )
9.5 m Unmanned ribs capable of limited MCM , ASW or area control
Wildcat fitted with 4 x Sea Venom , 20 x LMM , Stingray , or a mix of
A re-enforced Platoon of RM

these 16 ships would be all about being the eyes and ears of the RN over seas but with some real bite

If you /we want to operate large Unmanned kit it should be done from the MRSS fleet or at this time the Bay's or LPD

For me if we could get to a place where we had 4 T-31's and 4 RB2's each side of Suez and have both classes 1.5 Manned and push type 31 for 240 days at sea and the RB2's to 300 days this could mean we could be looking at have a type 31 at sea for just short of 300 days a year in the Gulf , Indian Ocean and Pacific at the same time and the RB2's at sea for 600 days a year in the Indian Ocean and Pacific

SW1 wrote: ↑12 Mar 2023, 10:20 I don’t know how many time that type 31 myth needs busted.. The type 31 are fwd deployed protecting our interests primarily outside of the NATO area

No myth. The RN has very clearly stated the T31's capability and use i.e. flag waving and maritime constabulary.

The RN has also stated that they will act as escorts for the LSG -so not just flag waving & maritime constabulary.

Caribbean wrote: ↑12 Mar 2023, 16:01 The RN has also stated that they will act as escorts for the LSG -so not just flag waving & maritime constabulary.

It was also stated by the last Sea Lord that they would be sent into harms way