Current & Future Escorts - General Discussion

[Ron5]

Babcock's claim they totally redesigned a great deal of the IH to create the T31 including all of the superstructure. If you believe that, I would question why a T26 type mission bay was not added. I doubt if top weight was an issue considering the parent used to have a frikkin' big radar up there to go with a Mk 41.

Complete nonsense. Babcock have made no such claim. In fact they have made the opposite i.e. there has been minimal change. There is an interview by Xav from DSEI 2019? where John Howie talks about it. They have straightened the funnels and moved the weapons deck up to fit the extra boat bay(s) in that's it.

I agree that in 2019 when they were trying to win the contract, they placed huge emphasis on the T31 being a "proven" design that required a tiny bit of change. Hence being the low risk option. I wasn't the only one to raise questions about the huge risk inherent in their total lack of any relevant experience in designing and building frigates at a site where they hadn't built a ship from scratch before. They also said that Rosyth would mainly be assembly of blocks built elsewhere i.e. at experienced shipyards. That didn't happen either.

Nowadays (after winning the contract) they say that seeing the design is mostly theirs: a) it's up the RN standards, b) they can easily modify to meet other requirements and c) they're the best folks to advise on local build. Notice how they shouldered out the Danes to get the Indonesia contract.

Let me quote what a RN guy close to the project wrote last month in response to someone saying the T31 is mostly a Danish design:

Incorrect, hull was a preexisting design, but the T31 version, internal & topside arrangements, systems, weapons, etc. are a British design.

The T31 is Iver Huitfeldt with minor modifications. Widened bridge wings, straightened funnels, APAR removed from foremast, aft radar mast reduced to stub, weapons deck moved up a deck to fit boat bay (it is already an empty void on IH). Internally some mods have been made to meet updated/RN standards and replace obsolete equipment. I understand these are extra bulkhead in the workshop between the two engine rooms. Now it does have a completely different CMS\Radar\Weapons fit to the IH but these are Dutch\Swedish design.

Overall I would say the T31 is a British variant of the IH but it is in no way a British design. Now in comparison the Constellation class version of the FREMM is vastly different to both the Italian and French versions.

It would be interesting how much of the Indonesian money gets passed forward to the Danes. I'm guessing very little.

[Caribbean]

Ships strength is conferred by the hull girder.

Only if it doesn't have a superstructure, like a tanker or bulk carrier. In a ship WITH a superstructure (longer than 15-20% of the hull length, such as in a warship or passenger ship, where the superstructure is often of greater depth than the hull) it contributes significantly to hull strength and is taken into account when specifying the hull design. The early T26 design did not incorporate a mission bay - adding one caused significant design difficulties, presumably with having to transfer the loads through the mission bay roof and around the mission bay doors. The larger the opening, the larger the concentration of stress in the corners of the opening.

Can't remember where I read it originally - probably TD or STRN or some such. However, if you Google, you can find online academic articles that confirm my understanding.

[tomuk]

Babcock's claim they totally redesigned a great deal of the IH to create the T31 including all of the superstructure. If you believe that, I would question why a T26 type mission bay was not added. I doubt if top weight was an issue considering the parent used to have a frikkin' big radar up there to go with a Mk 41.

Complete nonsense. Babcock have made no such claim. In fact they have made the opposite i.e. there has been minimal change. There is an interview by Xav from DSEI 2019? where John Howie talks about it. They have straightened the funnels and moved the weapons deck up to fit the extra boat bay(s) in that's it.

I agree that in 2019 when they were trying to win the contract, they placed huge emphasis on the T31 being a "proven" design that required a tiny bit of change. Hence being the low risk option. I wasn't the only one to raise questions about the huge risk inherent in their total lack of any relevant experience in designing and building frigates at a site where they hadn't built a ship from scratch before. They also said that Rosyth would mainly be assembly of blocks built elsewhere i.e. at experienced shipyards. That didn't happen either.

Nowadays (after winning the contract) they say that seeing the design is mostly theirs: a) it's up the RN standards, b) they can easily modify to meet other requirements and c) they're the best folks to advise on local build. Notice how they shouldered out the Danes to get the Indonesia contract.

Let me quote what a RN guy close to the project wrote last month in response to someone saying the T31 is mostly a Danish design:

Incorrect, hull was a preexisting design, but the T31 version, internal & topside arrangements, systems, weapons, etc. are a British design.

The T31 is Iver Huitfeldt with minor modifications. Widened bridge wings, straightened funnels, APAR removed from foremast, aft radar mast reduced to stub, weapons deck moved up a deck to fit boat bay (it is already an empty void on IH). Internally some mods have been made to meet updated/RN standards and replace obsolete equipment. I understand these are extra bulkhead in the workshop between the two engine rooms. Now it does have a completely different CMS\Radar\Weapons fit to the IH but these are Dutch\Swedish design.

Overall I would say the T31 is a British variant of the IH but it is in no way a British design. Now in comparison the Constellation class version of the FREMM is vastly different to both the Italian and French versions.

It would be interesting how much of the Indonesian money gets passed forward to the Danes. I'm guessing very little.

Interesting question did the Danes get a one of upfront license fee or a cut of future sales or a combination of both?

Do you remember these article from last year about a deal between the Indonesians and OMT?
https://www.janes.com/defence-news/news ... nt-frigate

How does that fit with Babcock? What a tangled web.

[seaspear]

This could be a type of U.A.V that may be deployed from the mission bay bringing capabilities complementing the asw abilities of the type 26it may of course be slightly larger and heavier than present abilities to handle such craft but such an ability could be handy
https://www.popularmechanics.com/milita ... es-boeing/
https://nationalinterest.org/blog/reboo ... ure-186005

Trouble with submarine sized UAVs are that they come with submarine sized price tags.

I m not suggesting it would be "cheap" but the a ability to launch submersible assets with similar capabilities
https://news.usni.org/2019/02/13/41119
Certainly, China is deploying submersibles for a range of operations
https://www.taiwannews.com.tw/en/news/4244419
Sending a large such drone in the place of a submarine with some abilities may not replace a conventional submarine but would be cheaper than said submarine if it was able to perform some of those duties certainly at greater depths in some cases

[donald_of_tokyo]

Moved across from T26 news thread....

Because the UK can only afford 14-16 tier one warships and that doesn’t support two yards.

In the recent past, yes.....Going forward I'm not so sure.

Current planning is slowly coming to realise that a western technological superiority can no longer be relied upon. Consequently everything changes. A rate of attrition once again has to be factored into all planning scenarios. Only Fourteen Tier1 Destroyers and Frigates is a ridiculously low number for a nation with 2 CVF's and 4 SSBN's. If the global security picture continues to worsen then more credible escorts will be required probably along with a higher number of F35's.

All these extras cost money and prudence may dictate that the T83 is not built on the finest ASW hull the world has ever seen, the T45 certainly isn't. Therefore, if it's a clean sheet of paper design what advantage does BAE have over Babcock, especially if the new Frigate Factory at Rosyth turns out to be a whole lot more efficient than the Govan/Scotstoun operation?

Contrary to popular belief, I don't think that the T83 will necessarily be based on the T26 hull and if that is the case it's far from a done deal as to which yard is chosen to fabricate the hulls.

Scotland is Scotland.

Yeah, it's really a bit more complex than that.
But this is a news only thread, so perhaps the last dozen posts need deleting.

Simple comments:
- I do not see possibility of RN growing to 20-24 tier-1 escorts, from current 14, anytime soon.
- I agree T83 may not be based on T26-hull, but I do think it must be developed from the team who designed T26. They did a great job.
- If T83 goes to Babcock, then I think BAES Clyde will simply close. It is HMG who insist on "competition", not the industry side.

"Competition in escort building" is a very unique strategy, none of the western country other than USA is taking. There is no guarantee it will be successful. Personally, I see no good way to make it successful. Just growing a few very weak shipyards, BOTH cannot survive without governmental supports. Is this competition?

Anyway, as you all know, final state of competition is "monopoly". Textbook case. To keep the "competition" in this small industry field, HMG needs to balance their order. In short, UK needs "cartel", which is not a competition anymore. Let's call it "quasi-competition".

From this "balance" to maintain quasi-competition, T83 must go to BAES Clyde. Call it politics, or balance, or cartel. No other way, I think.

[tomuk]

From this "balance" to maintain quasi-competition, T83 must go to BAES Clyde. Call it politics, or balance, or cartel. No other way, I think.

I believe it is called the Defence and Security Industrial Strategy.

[Repulse]

I do not see possibility of RN growing to 20-24 tier-1 escorts, from current 14, anytime soon.

I agree with your overall statement Donald-san, but with a bit more vision and balls to give certainty to suppliers we could get a couple more without a significant increase in funds. For example, I've not seen it written down anywhere but it was heavily rumored that if the MOD had committed to the purchase of 8 T26s rather than 3, BAE would have built a 9th for the same price. It makes perfect business sense for everyone - by buying in "bulk" you get a discount. Now if the MOD did a "bulk" deal for the remaining 5 T26s and T83s over the next two decades, could they get 13 for the price of 11?

[Poiuytrewq]

- I do not see possibility of RN growing to 20-24 tier-1 escorts, from current 14, anytime soon.

Actually, on the balance of probability I think the Tier-1 escort fleet is likely to increase rather than decrease due to the global security situation.

- I agree T83 may not be based on T26-hull, but I do think it must be developed from the team who designed T26. They did a great job.

The best outcome is an AAW version of the T26 which of course would be a closed book. If RN start flirting with a class of cruisers the field is wide open IMO.

- If T83 goes to Babcock, then I think BAES Clyde will simply close. It is HMG who insist on "competition", not the industry side.

Disagree. There is room for both if HMG keeps the drum beats going due to the RN need for so many escorts in the next couple of decades. The big unknown is whether the T26/T83/T31/T32 plan will survive the next SDSR. Personally I would give it nothing better than 50:50.

[Rentaghost]

Slightly off tangent from the recent posts, but something of a historical question - and could be more generally applied but the escort thread seems a decent place to ask...

Why has the RN never gone in for the Prairie/Masker system?

[Tempest414]

for me the tire 1 tier 2 thing is what the navy needs yes we could do with a few more tier 1 something like 9 ASW and 9 AAW ships and the only way this is going to happen is having a type-26 based AAW. As for the tire 2 we could have a full fat type 31 for half the cost of the tire 1's and when I say full fat I mean the type 31 as is with 30 CAMM , 8 x SSGW & a sonar added this would be a good workhorse for the navy

[Timmymagic]

Why has the RN never gone in for the Prairie/Masker system?

UK had/has its own system called Agouti
RN has had a greater focus on reducing signature on ships for longer than the US, but they have used the Prairie part on Type 22 Batch 2's. The props had the 'Agouti' system, which worked similar to the 'Masker' part. Other RN vessels have also had Agouti. Notable that the Type 22's were noisier than Leander and weren't seen as good for ASW as a result. Type 23 focused on noise reduction to an enormous degree. To be honest I'm not sure if they had/have either system.

Interestingly the RAN used Prairie/Masker AND Agouti on their Adelaide Class ships.

[Rentaghost]

Why has the RN never gone in for the Prairie/Masker system?

UK had/has its own system called Agouti
RN has had a greater focus on reducing signature on ships for longer than the US, but they have used the Prairie part on Type 22 Batch 2's. The props had the 'Agouti' system, which worked similar to the 'Masker' part. Other RN vessels have also had Agouti. Notable that the Type 22's were noisier than Leander and weren't seen as good for ASW as a result. Type 23 focused on noise reduction to an enormous degree. To be honest I'm not sure if they had/have either system.

Interestingly the RAN used Prairie/Masker AND Agouti on their Adelaide Class ships.

Huh, that's really interesting - thanks. Guess it's something you don't see much about in the public domain.

I do wonder about the effectiveness of the Prairie system against modern passive sonar systems. I get that the acoustic impedance mismatch will reduce the range at which you could discriminate the specific machinery noises, but it will have it's own self noise - the cavitation from the bubbles- that should be detectable. You might not be able to tell apart one ship from another, but you should be able to tell that there is a ship there...

Is it better then to concentrate on reducing overall acoustic emissions rather than masking them?

[Ron5]

Babcock's claim they totally redesigned a great deal of the IH to create the T31 including all of the superstructure. If you believe that, I would question why a T26 type mission bay was not added. I doubt if top weight was an issue considering the parent used to have a frikkin' big radar up there to go with a Mk 41.

Complete nonsense. Babcock have made no such claim. In fact they have made the opposite i.e. there has been minimal change. There is an interview by Xav from DSEI 2019? where John Howie talks about it. They have straightened the funnels and moved the weapons deck up to fit the extra boat bay(s) in that's it.

I agree that in 2019 when they were trying to win the contract, they placed huge emphasis on the T31 being a "proven" design that required a tiny bit of change. Hence being the low risk option. I wasn't the only one to raise questions about the huge risk inherent in their total lack of any relevant experience in designing and building frigates at a site where they hadn't built a ship from scratch before. They also said that Rosyth would mainly be assembly of blocks built elsewhere i.e. at experienced shipyards. That didn't happen either.

Nowadays (after winning the contract) they say that seeing the design is mostly theirs: a) it's up the RN standards, b) they can easily modify to meet other requirements and c) they're the best folks to advise on local build. Notice how they shouldered out the Danes to get the Indonesia contract.

Let me quote what a RN guy close to the project wrote last month in response to someone saying the T31 is mostly a Danish design:

Incorrect, hull was a preexisting design, but the T31 version, internal & topside arrangements, systems, weapons, etc. are a British design.

The T31 is Iver Huitfeldt with minor modifications. Widened bridge wings, straightened funnels, APAR removed from foremast, aft radar mast reduced to stub, weapons deck moved up a deck to fit boat bay (it is already an empty void on IH). Internally some mods have been made to meet updated/RN standards and replace obsolete equipment. I understand these are extra bulkhead in the workshop between the two engine rooms. Now it does have a completely different CMS\Radar\Weapons fit to the IH but these are Dutch\Swedish design.

Overall I would say the T31 is a British variant of the IH but it is in no way a British design. Now in comparison the Constellation class version of the FREMM is vastly different to both the Italian and French versions.

It would be interesting how much of the Indonesian money gets passed forward to the Danes. I'm guessing very little.

Interesting question did the Danes get a one of upfront license fee or a cut of future sales or a combination of both?

Do you remember these article from last year about a deal between the Indonesians and OMT?
https://www.janes.com/defence-news/news ... nt-frigate

How does that fit with Babcock? What a tangled web.

Yes I remember which is why I mentioned it in my comment

PS most unlikely that either side would just settle for a fixed one time license fee. Most likely would be a license for the RN's T31's and a cut of any T31 export deals based on amount of UK vs Danish content. Hence my comment.

[Ron5]

This could be a type of U.A.V that may be deployed from the mission bay bringing capabilities complementing the asw abilities of the type 26it may of course be slightly larger and heavier than present abilities to handle such craft but such an ability could be handy
https://www.popularmechanics.com/milita ... es-boeing/
https://nationalinterest.org/blog/reboo ... ure-186005

Trouble with submarine sized UAVs are that they come with submarine sized price tags.

I m not suggesting it would be "cheap" but the a ability to launch submersible assets with similar capabilities
https://news.usni.org/2019/02/13/41119
Certainly, China is deploying submersibles for a range of operations
https://www.taiwannews.com.tw/en/news/4244419
Sending a large such drone in the place of a submarine with some abilities may not replace a conventional submarine but would be cheaper than said submarine if it was able to perform some of those duties certainly at greater depths in some cases

I didn't mean to sound like I was criticizing your comment. It's a good one to make as we are discussing mission bays. Merely pointing out something that will limit their widespread use

[Ron5]

Simple comments:
- I do not see possibility of RN growing to 20-24 tier-1 escorts, from current 14, anytime soon.
- I agree T83 may not be based on T26-hull, but I do think it must be developed from the team who designed T26. They did a great job.
- If T83 goes to Babcock, then I think BAES Clyde will simply close. It is HMG who insist on "competition", not the industry side.

"Competition in escort building" is a very unique strategy, none of the western country other than USA is taking. There is no guarantee it will be successful. Personally, I see no good way to make it successful. Just growing a few very weak shipyards, BOTH cannot survive without governmental supports. Is this competition?

Anyway, as you all know, final state of competition is "monopoly". Textbook case. To keep the "competition" in this small industry field, HMG needs to balance their order. In short, UK needs "cartel", which is not a competition anymore. Let's call it "quasi-competition".

From this "balance" to maintain quasi-competition, T83 must go to BAES Clyde. Call it politics, or balance, or cartel. No other way, I think.

Excellent summary Donald-san

[Ron5]

Yes, I know that about Ikara, but why didn't they continue with Ikara on later classes, like Type 22? Or even ASROCs, because I think that even ASROC is better than ordinary torpedo tubes?

End of the Cold War, recognition that VL or canister launched 'sealed rounds' was the way forward from 'built up' systems like Ikara, evolution of the threat (Russian missile boats made Ikara fairly redundant), evolution of helicopters (better ability in all weathers, combined hunter-killers like SeaKing and Merlin), sonar capable of detection at far longer ranges. Whole heap of reasons really.

Ikara was a huge system that didn't work very well and even when it did, wasn't that useful.

[Ron5]

Ships strength is conferred by the hull girder.

Only if it doesn't have a superstructure, like a tanker or bulk carrier. In a ship WITH a superstructure (longer than 15-20% of the hull length, such as in a warship or passenger ship, where the superstructure is often of greater depth than the hull) it contributes significantly to hull strength and is taken into account when specifying the hull design. The early T26 design did not incorporate a mission bay - adding one caused significant design difficulties, presumably with having to transfer the loads through the mission bay roof and around the mission bay doors. The larger the opening, the larger the concentration of stress in the corners of the opening.

Can't remember where I read it originally - probably TD or STRN or some such. However, if you Google, you can find online academic articles that confirm my understanding.

I did a quick Google and didn't find anything to support your claims that the T26 mission bay was difficult and expensive to design and build.

In response to your comments on ship strength:

1. As you point out, how much strength is or is not conferred by superstructure, is by designer choice. Not act of God.

2. There are limits to how much strength should by contributed by warship superstructure due to many factors including: it's usual lighter construction, it's lack of continuity from stem to stern, it's many "empty" box like sub structures such as hangars & boat bays, the requirements of low RCS, and the desire to limit overall ship vulnerability in parts of the ship at higher risk of damage by enemy action.

3. Designing strong steel boxes with "bloody great holes" is not a difficult engineering task. Neither is reinforcing structure around an opening. Tasks that a naval architect is very familiar with. Especially one engaged in warship design. And even if the design causes an architect a few gray hairs, the solution is welded steel. Cheap and easy.

4. The one kinda valid point somebody made was that the T26 mission bay crane is sophisticated and expensive. That's true, it's quite a marvel of engineering. But a mission bay doesn't require such a fancy crane so it's costs are really outside of this discussion.

In conclusion, the T26 mission bay and Chinook flight deck add a few hundred tons of steel to the design. But very little cost. Which is why, as I said before, they probably survived the Treasury's penny pinchers.

[Lord Jim]

Both German and the Netherlands either have or are conducting a competition for their next classes of high end escorts.

[donald_of_tokyo]

Both German and the Netherlands either have or are conducting a competition for their next classes of high end escorts.

Thanks. My impression is that the German shipyards a "balanced", so not a competition. This time "the whole German ship yard" failed against Damen, but I think anyway the ship will be built in the German shipyards? (I am not well informed here, sorry).

Netherlands frigate is, also, looks like in competition but, for me, it is nothing less than quasi-competition. There are no case Damen does not build the hull.

In UK competition, if Rosyth wins, Clyde builds nothing, and vice versa. If such thing happens in Netherlands, actually Damen may survive, because they have a healthy build record and export record of many other vessels. BAES Clyde? Babcock Rosyth? Nothing. All combined, the situation is very very different.

Without "balance", UK escort shipyards will be in monopoly very soon (either BAE Clyde or Babcock Rosyth), I guess. Hence, T83 must go to Clyde.

[Scimitar54]

Or BAE might purchase Babcock.

[Lord Jim]

Yes Damen are working with a German shipyard, forgotten exactly which one, and the new Frigates will be built there. As for teh Netherlands, I agree Damen are all but certain to win that competition, but another competition for four Submarines for the Dutch Navy is also being competed. This time it is far from certain who will win, with the Swedes and the Germans putting in strong bids.

[Poiuytrewq]

In UK competition, if Rosyth wins, Clyde builds nothing, and vice versa.

Too many variables going forward to be sure this still holds true.

Based on current planning the U.K. will construct the following in the coming decades:

8x Type26
5x Type 31
5x Type 32
? Type 83
3x FSS
1x(2x) MRSV
6x MRSS

Plus potential replacements for the OPV’s, Waves and Points etc

Also, how does AUKUS change the landscape?

Will Barrow increase capacity or could Govan and Rosyth pick up some of the work?

Could the T83 become a common AUKUS destroyer in much the same way SSN(R) could become an AUKUS SSN.

A lot depends on the level of HMG’s ambition going forward.

[Dobbo]

There is a lot to be said about substantive commonality between the T-83 and SSNR (at least as between the U.K. and Australia) if both countries wish to have a cutting edge warship / boat in sufficient numbers (for the U.K. I would say that is at least 8 of each with ideally 10 SSNR - the deteriorating situation suggests to me that the RN is likely to grow in the coming decades).

[Poiuytrewq]

More good news!

From the Telegraph:

Admiral Sir Tony Radakin is expected to be formally announced as the new defence chief on Thursday
The First Sea Lord and Chief of the Naval Staff has been selected by the Prime Minister as the next head of the Armed Forces, The Telegraph can reveal.

Admiral Sir Tony Radakin will take over from General Sir Nick Carter as Chief of the Defence Staff, making him the first military chief to come from the Navy since Admiral Sir Michael Boyce in 2001.

Sources close to General Sir Patrick Sanders, who was seen as the First Sea Lord’s biggest threat to securing the role and believed to be the Ministry of Defence’s recommendation for the position, confirmed he had not been successful in the race.

They added that he was “relaxed” about the decision.

Downing Street is expected on Thursday to formally announce Boris Johnson's choice of defence chief.

It is understood that Vice-Admiral Sir Ben Key, who led the Afghanistan evacuation and is in charge of all overseas military operations, will be promoted to Admiral and replace Sir Tony as First Sea Lord.


The contest for the new head of the Armed Forces has long been considered a two-horse race between Sir Tony, for his knowledge of the seas and Sir Patrick, owing to his deep understanding of how to integrate cyber capabilities into the Armed Forces.

However, others in the mix to clinch the post included General Sir Mark Carleton-Smith, the former head of Britain’s special forces and a personal friend of Mr Johnson.

Under Sir Tony, the UK has seen two new aircraft carriers brought into service. He also oversaw the deployment of one, HMS Queen Elizabeth, including escort ships and a hunter-killer submarine, to the Indo-Pacific region. As a result the Royal Navy is seen as embodying the Government’s Global Britain agenda.

Meanwhile sources have said that the recent Aukus deal with the US and Australia over the future provision of nuclear submarine capability reflected well on the First Sea Lord.

Earlier this year The Telegraph revealed that Sir Nick, 62, who was in his third year as Chief of the Defence Staff and was due to retire, would remain in post until the end of the year so that he could lead the transformation of the military following the Integrated Defence Review.

https://www.telegraph.co.uk/news/2021/1 ... ed-forces/

[SD67]

In UK competition, if Rosyth wins, Clyde builds nothing, and vice versa. If such thing happens in Netherlands, actually Damen may survive, because they have a healthy build record and export record of many other vessels. BAES Clyde? Babcock Rosyth? Nothing. All combined, the situation is very very different.

But it's BAE vs Babcock not Clyde vs Rosyth. BAE could lose and sell the Clyde yard to Babcock. BAE could win and shut down the Clyde anyway. In any case they're only an hour apart, workers can and do move between them. Personally I think the Govan at least is going to close anyway because T83 will simply be too large for it.