Royal Navy nuclear surface ships

[Madurai]

What's a nuclear funnel?. What's the role of a funnel in a nuclear ship? ???

As long as we're responding to years-old posts...

There is a reason for a funnel in nuclear surface ships: blowout vents in case of coolant leaks.

 

[CNH]

AS seen in the AEA annual report, ATOM, of 1963.
Discussed in my new book [now at publishers]

 

[CNH]

'An Atomic Empire'

 

[RyanC]

There is a reason for a funnel in nuclear surface ships: blowout vents in case of coolant leaks.

Don't forget air intakes for ventilation! If you place it in a funnel, you have room for the NBC Filters so that they don't impact below decks on precious volume.

 

[CNH]

The text and images have just gone to the publishers for proof reading and type setting. At a guess - sometime in the spring!

 

[RP1]

Regarding funnels on nuclear powered ships;


Remember that you may have a quite substantial back up diesel plant, which needs exhausts. The chimney effect of the funnel can also provide a substantial mount of air circulation to help remove decay heat from the reactor compartment (The reactor may vent steam to the containment, which remains sealed and acts like a buffer, and you can circulate air around the exterior of the containment). The air in the "outer" compartment will become radioactive (isotopes of O2 and N2) in normal operation, but these have short half lives and so just exhausting the air through a tall funnel was deemed to be acceptable in some cases.


RP1

 

[chimeric oncogene]

I thought the French used plutonium in their submarine reactors. In places with reactor fuel reprocessing with PUREX, reactor-grade plutonium should be relatively inexpensive and have similar properties to HEU, perhaps at lower cost.

I think the French have always used LEU submarine fuel, the British always HEU. China, no idea.

 

[chimeric oncogene]

The "French"? all of them? 67 million people, each using plutonium in submarines? woa! All propulsion reactors in France's Marine nationale's use are fuelled with oxyde LEU. MOX, if it is what is meant here, is not involved.

My mistake. Thank you for correcting me.
Why doesn't anyone use reactor-grade plutonium in submarine reactors? The French reprocess their nuclear fuel - reactor grade plutonium should be readily available for a program, if they so desired one?
A reactor with 50% Pu-240 and 50% Pu-239 (this is really bad reactor grade Pu) should outperform one with 50% enriched uranium. And the few tonnes of reactor-grade Pu needed for a reactor should be obtainable from a large 50-GW civil nuclear power program...
The French government is definitely smarter than me, so I'm missing something.

 

[A Tentative Fleet Plan]

I could have sworn that I've seen this elsewhere on the forum, but it's not on this thread, but here is the model described earlier in the thread.

1965 1:96 Scale RFA with Y502 Machinery.

 

[Pioneer]

I know the Italians had (have) very particular styles in Naval Architecture. but could the attached of the poposed Enrico Fermi give any suggestions for a "Military" RFA??

Wow, very impressive armament for a replenishment ship!!

Regards
Pioneer

 

[JFC Fuller]

Prior to lockdown I started doing archive research on RN interest in nuclear propulsion for surface ships. I originally went looking for studies of nuclear propulsion for CVA01 referenced in 1963 cabinet minutes but found there is a significant amount of surviving material relating to studies undertaken from the late 1950s to the late 1960s. I only got one afternoon at this so what follows is not founded on the most rigorous research.

Y502 Replenishment Ship: Following the 1957 review there were eight replenishment ships in the long-term plans, these could be nuclear powered and the option existed to have a smaller number of larger vessels. The reason for the replenishment ship being proposed seems to be that the Admiralty thought they could get the AEA to use it's funds for the development of the reactor under the auspices of an associated civilian ship propulsion programme. The Admiralty apparently having no intention of funding such development itself.

75,000SHP Destroyer Plant: Dating to 1958 this appears to have started out as a generic study into nuclear propulsion for warships that quickly focussed on a hypothetical plant for the Hampshire class, the report is incredibly detailed and culminates in a very detailed machinery space layout for a CONAG plant. However, the reactors are anything but detailed, there is discussion of different reactor types but the ultimate drawings just show empty boxes with the relevant SHP written in them. This study may have been where some of the nuclear propulsion configurations referenced by Friedman in relation to NIGS came from.

1964 45-50,000 SHP reactor: Circa 1964 consideration was again being given to nuclear propulsion for surface ships. The RN is talking to Babcock and Wilcox about it's Consolidated Nuclear Steam Generator (CNSG) reactor, looking at development of the existing submarine plants and a proposed AEA Burnable Poisons Reference Design (BPRD). Thinking was that one such reactor could be used to propel frigates, two could be used to propel cruisers and three could be used to propel carriers so that the RN would only need one reactor design.

Nuclear Type 82: This was inspired by the 1965 cancellation of the nuclear powered merchant ship by the Ministerial Committee on Economic Development. A steering committee was set up and it suggested a £350,000 9-12 month sketch design of a nuclear powered Type 82. However, prior to the study being started it was decided to link it to ongoing submarine reactor R&D. By now the T82 had been capped at one unit so a ship representative of those to be built in the future would have to be used. There looks to have been no intention to build such a ship, rather it was an exercise in developing a detailed design that could be compared against an actual conventionally powered vessel with otherwise identical characteristics. The RN had been hoping to learn about nuclear propulsion by observing AEA funded projects, when this option finally disappeared they looked at funding their own study.

Small Ship Nuclear Propulsion: A 1968 study looking at nuclear propulsion for smaller ships concludes that a 4-5,000 ton deep displacement warship with a single reactor CONAG plant of 35-45,000 SHP installed power is viable. I only found the report itself but it is tempting to believe that the report was the end result of the nuclear Type 82 study referenced above, with the T82 capped at one unit future frigates would be smaller.

In summary, the nuclear powered replenishment ship was probably something the RN was only interested in if someone else was paying the reactor R&D costs. Aside from that, there was very significant interest in nuclear propulsion for warships for at least a decade, the study work was detailed and rigorous and came to some very interesting conclusions. In the end though, there never seems to have been a truly serious prospect of the RN adopting nuclear propulsion for surface ships.

 

[uk 75]

JFC Thank you for getting this excellent and comprehensive round-up of RN surface ship planning.
The US experience of building and operating nuclear powered escorts reinforces the view that it would have been too costly as well as down sides like not being welcome in certain countries like New Zealand.
Even the mighty USN didnt deploy nuclear powered supply ships, though when NS Savannah was built they might have planned them.
CVA01 would like Charles DeGaulle have been a candidate especially as the RN gave up steam boilered ships, but costs and controversy made it a non starter.
A nuclear County or Type 82 would be one for Hood or Tzoli

 

[Tzoli]

Yes when this Virus fiasco is over (either by running it's course or a cure was found) I would like to hear more about those projects!

 

[Grey Havoc]

I thought that this had already been posted somewhere but apparently my memory is playing tricks on me again. Via the C3L Security blog:

EDIT: Ack! My memory wasn't acting up after all, A Tentative Fleet Plan had posted a link to images of it already!

 

[Grey Havoc]

Some information on the nuclear powered SIGINT ship project, which examined both clean sheet designs & ultimately (and perhaps rather unwisely) a conversion of an existing carrier, can be found in this thread. Cover designation was 'Communications Trials Ship'.

 

[CNH]

Slightly off topic, this is a design for a reactor for a nuclear submarine (thread drift, since obviously not a surface ship) presented at the Harwell Power Conference of 1951. It was graphite moderated and cooled with helium. For a variety of reasons, this was not a particularly practical design.

Putting it into a submarine would be something of a challenge. It does seem rather susceptible to damage in the case of depth charging. Raising steam from such a reactor would probably take quite some time. No examination is made of the nature of the fuel rods, and as we later found out from DRAGON, using helium as a coolant is not the easiest of propositions.

 

[CNH]

I was also rather amused by a further follow-on memorandum: the boffins had decided that a liquid metal cooled reactor might do the job. A report was prepared and sent to the Admiralty. The First Lord of the Admiralty (a political appointment of cabinet rank), who had asked to be kept up-to-date, and was sent a copy of the report, wrote on it, rather plaintively,

'Can someone explain this to me in simple language?! JPLT'

Mind you, this is as nothing compared with the Scottish MP who asked a question in Parliament, referring to nuclear power for ships, as to whether:

‘Can the Minister say how long it will be before this power could be available for fishing trawlers?’

 

[TomS]

Mind you, this is as nothing compared with the Scottish MP who asked a question in Parliament, referring to nuclear power for ships, as to whether:

‘Can the Minister say how long it will be before this power could be available for fishing trawlers?’

Not a totally daft question in the era when nuclear-powered automobiles were being thrown about in public.

 

[Grey Havoc]

From 1958:
United Kingdom Atomic Energy Authority INDUSTRIAL GROUP
Information Bibliography
NUCLEAR PROPULSION FOR SHIPS

 

[Pioneer]

I know the Italians had (have) very particular styles in Naval Architecture. but could the attached of the poposed Enrico Fermi give any suggestions for a "Military" RFA??

Wow, this Replenishment ships design appears to be better armed than most destroyers!

Was it proposed to be nuclear powered?
Do we know what timeframe/year this design was proposed by Enrico Fermi?


Regards
Pioneer

 

[Pirate Pete]

I know the Italians had (have) very particular styles in Naval Architecture. but could the attached of the poposed Enrico Fermi give any suggestions for a "Military" RFA??

Wow, this Replenishment ships design appears to be better armed than most destroyers!

Was it proposed to be nuclear powered?
Do we know what timeframe/year this design was proposed by Enrico Fermi?


Regards
Pioneer

The ‘Enrico Fermi’ was indeed intended to be nuclear powered.
I cannot recall precisely which publication it came from, but I think it was ‘Maritime Defence’ from the mid to late 1970’s.

 

[Grey Havoc]

On a side note:

Keith Foulger, naval constructor who worked on the UK’s nuclear submarine fleet – obituary

He ensured that there was no mismatch between US and British technology in the design of Britain’s first nuclear submarine, Dreadnought

www.telegraph.co.uk

RIP

Interestingly, not only was he involved in just about every major Royal Navy nuclear powered submarine project of the Cold War, he also seems to have worked on cruiser designs as well, especially during the 1969-1974 period, though some of those were certainly conventional designs.

 

[Grey Havoc]

On a side note:

Keith Foulger, naval constructor who worked on the UK’s nuclear submarine fleet – obituary

He ensured that there was no mismatch between US and British technology in the design of Britain’s first nuclear submarine, Dreadnought

www.telegraph.co.uk

RIP

Interestingly, not only was he involved in just about every major Royal Navy nuclear powered submarine project of the Cold War, he also seems to have worked on cruiser designs as well, especially during the 1969-1974 period, though some of those were certainly conventional designs.

 

[zen]

So Royal Navy's Trident submarines have reactors of US design, right?

Nope. PWR-2 was expressly designed to contain as little US IP as was realistically achievable at the time.

 

[uk 75]

It is worth noting that the ambitious lineup of US Navy surface escort warships which was symbolised by Long Beach and Bainbridge escorting Enterprise in many glorious photos in the early 60s had vanished by the 1970s as the costs and difficulties of operating nuclear surface ships became apparent.
The Virginia class became the last 4 USN nuclear surface escorts. With the end of the Cold War they and their earlier sisters were taken out of service in the early 90s.without replacement.
Without a nuclear CVA01 there was no chance of the RN getting nuclear County's or Tide class RFAs.
They would have fitted well into the Dan Dare world envisaged in the graphic novel Ministry of Space.

 

[Hood]

From reading the history in Friedman's Cold War British Subs it sounds like the Admiralty were far more interested in commerical reactors that could be used on merchant ships, which they thought were the next big thing. That probably explains why the planned use was for an RFA tanker as a more suitable prototype ship to entice commerical buyers.
Nuclear briefly appeared for Type 82 studies but was probably purely a speculative foray for comparative purposes.

Luckily they snapped out of it and focused on submarines and avoided an expensive white elephant.

 

[Grey Havoc]

The TF2050 frigate design (arguably more of a heavy corvette), aka the 'Dreadnought 2050', from a few years back. Nuclear (fusion) and gas turbine powered:

https://www.secretprojects.co.uk/threads/rn-warship-2050-project-startpoint.25277/

 

[A Tentative Fleet Plan]

Mind you, this is as nothing compared with the Scottish MP who asked a question in Parliament, referring to nuclear power for ships, as to whether:

‘Can the Minister say how long it will be before this power could be available for fishing trawlers?’

https://hansard.parliament.uk/Commons/1960-02-03/debates/7ef62542-4ebf-4e46-81e7-b675667aad7c/Shipping

 

[Grey Havoc]

Scotstown, Glasgow

From the arrival of Yarrow Shipbuilders to BAE Systems Surface Ships, Scotstoun is at the very heart of Glasgow Shipbuilding excellence.

www.baesystems.com

Scotstoun briefly became involved in an Admiralty Research project with English Electric although when they withdrew in 1947 a new facility was established and became known as the Yarrow-Admiralty Research Department (Y-ARD). Two other organisations were also formed overseas: Y-ARD (Australia) and the Yarrow African Marine Consultancy which were both set up to meet the demand for land boilers.

The Admiralty continued to be a key customer for the yard over the next decade, ordering frigates and seaward defence boats and by 1954, the workforce was in excess of 2,500. Scotstoun continued its research into new technologies and in the late 1950s it was deep into the application of nuclear power for marine use. By 1961, Scotstoun marine engineers, shipbuilders and boiler makers at Scotstoun were carrying out extensive research into nuclear powered propulsion units.

 

[Rhinocrates]

Just an RFI at this stage, so I think the 'soon' in the headline is a bit inaccurate.

UK may soon be operating nuclear powered warships

The Royal Navy is exploring the feasibility of nuclear power for large surface ships, including support vessels and surface combatants.

ukdefencejournal.org.uk

The Royal Navy is specifically looking into the possibility of using Generation 4 nuclear technologies, including both larger nuclear reactors and micro modular reactors, for powering large surface ships.

[...]

A key feature is the development of smaller, modular designs like Small Modular Reactors (SMRs), which are more flexible and can be deployed in a wider range of settings, including for naval applications. These reactors also aim to reduce the environmental impact of nuclear power while maintaining high operational performance.

Small modular reactors:

Rolls-Royce SMR - Wikipedia

en.wikipedia.org

Small modular reactors

Rolls-Royce SMR LTD was established to develop an affordable power plant that generates electricity using a small modular reactor.

www.rolls-royce.com

 

[Scott Kenny]

Pardon me for a very old reply:

That would be my understanding of it - the topology shown in the diagrams would be awkward to fit in a submarine (tall and thin), and Babcock & Wilcox didn't design reactors for the USN. Given that this was a civilian plant, using a different design would remove security classifications, also.

Not remove, there's a separate clearance system run by Department of Energy for nuclear stuff, in addition to any military classifications.

I don't know much more about it than that there are two classifications, P and Q, broadly comparable to Secret and Top Secret respectively (I think I have that straight). I'd assume that ordinary reactors get the Secret-equivalent classification and the DOE side of nuclear weapons gets the TS-equivalent.

Oddly enough, Naval Nuclear Propulsion data in the USN is only Confidential-Restricted to US citizens only, not Secret.


=======================

Just an RFI at this stage, so I think the 'soon' in the headline is a bit inaccurate.

UK may soon be operating nuclear powered warships

The Royal Navy is exploring the feasibility of nuclear power for large surface ships, including support vessels and surface combatants.

ukdefencejournal.org.uk

The Royal Navy is specifically looking into the possibility of using Generation 4 nuclear technologies, including both larger nuclear reactors and micro modular reactors, for powering large surface ships.

[...]

A key feature is the development of smaller, modular designs like Small Modular Reactors (SMRs), which are more flexible and can be deployed in a wider range of settings, including for naval applications. These reactors also aim to reduce the environmental impact of nuclear power while maintaining high operational performance.

I doubt that it will end up happening, unless the new designs need a lot fewer people to operate.

Nuclear power takes a lot of bodies to run the reactor, while Gas Turbines take maybe 1/4 as many.

So you'd need to find the people with the right mindset, run them through training that is literally designed to fail at least 1 student every class cycle, and pray you find enough people.

I have a record of one submarines training evaluation, it's specifically unclassified: "Training was not rigorous enough, in that there were no overall examination failures and no individual question failures." And that's for continuing education. Someone is required to fail every test, and at least one question per test is supposed to be so hard NO ONE gets it right.

Crud, even the USN struggles to find enough Nukes.

 

[Rhinocrates]

Crud, even the USN struggles to find enough Nukes.

I've read somewhere why the RN isn't too worried that the QE class carriers or other surface ships aren't nuclear powered:

Some nations/ports ban nuclear powered vessels, limiting options for deployment

Security required when docked is much higher

Still need to replenish food, aviation fuel, and ammunition regularly anyway, the carriers are very rarely going to sail alone and the other vessels in the task group still need to be refuelled.

 

[Scott Kenny]

I've read somewhere why the RN isn't too worried that the QE class carriers or other surface ships aren't nuclear powered:

Some nations/ports ban nuclear powered vessels, limiting options for deployment

Security required when docked is much higher

Both true.

Still need to replenish food, aviation fuel, and ammunition regularly anyway, the carriers are very rarely going to sail alone and the other vessels in the task group still need to be refuelled.

At least for the US, we can refuel ships off the CVNs, in addition to pushing JP8 to them for running any helicopters they carry.

With the size of the QE class, I'm not sure they can act as a supply ship in addition to taking care of themselves.

 

[Yellow Palace]

Not remove, there's a separate clearance system run by Department of Energy for nuclear stuff, in addition to any military classifications.

Removing the requirement to manage both DoD and DoE restrictions would still be a big help, of course.

As far as DoE clearances go, there were originally three:

• P, for people with no access to Restricted Data and no requirement to access it;
• S, for people who didn't need access to Restricted Data but who would frequently be in places where it might be found; and
• Q. for people who need access to Restricted Data

Why those letters? Because the administrative form completed to grant them was the Personnel Security Questionnaire. The 'S' category has apparently now been retired, but an 'L' category exists (or existed) to provide 'Limited' access to Restricted Data.

How many people have Q Clearance?

Ever wonder how many people currently have the enigmatic Q Clearance, the required security clearance for access to nuclear secrets? Well, I found out.

blog.nuclearsecrecy.com

Someone is required to fail every test, and at least one question per test is supposed to be so hard NO ONE gets it right.

Frankly, that's a bad training system. If the standard is set at the right level, and everybody passes, that's a success. If you keep having to raise the standard to make sure you fail someone, you're arbitrarily reducing the number of qualified people you have access to.

And equally, if the standard is set at the right level, and everybody fails, that's also a success. You've determined that nobody in that class was suitable for the role.

I've read somewhere why the RN isn't too worried that the QE class carriers or other surface ships aren't nuclear powered:

TBH, the main reasons are money, politics, and crew. In more or less that order. The rest of it is largely spin.

If the Warship Fairies gifted the RN a nuclear-powered carrier and the people to crew it, they wouldn't turn around and complain that there were fewer runs ashore and that they still had to provide ammunition ships.

 

[zen]

So it's good practice to ask questions and explore options.....and perhaps not prejudge any conclusions.
In fact back in my day on every design oriented course I ever did, the examination of as many and as varied a set of options was considered the most thorough method.
Even if most be ruled out.
Ruling things out before you start is just bad practice.

 

[RP1]

The whole SMRs-for-ships thing is a bit of a distraction. I have to explain to someone at work roughly once a month that SMRs are around 300MW nett power and the RR ones are a PWR anyway. Nothing new there. Although some of the Gen IV and SMR topologies scale down, what is more interesting for ships are micro reactors, some information on the RR concept is here: Conference presentation link

 

[Scott Kenny]

Removing the requirement to manage both DoD and DoE restrictions would still be a big help, of course.

As far as DoE clearances go, there were originally three:

• P, for people with no access to Restricted Data and no requirement to access it;
• S, for people who didn't need access to Restricted Data but who would frequently be in places where it might be found; and
• Q. for people who need access to Restricted Data

Why those letters? Because the administrative form completed to grant them was the Personnel Security Questionnaire. The 'S' category has apparently now been retired, but an 'L' category exists (or existed) to provide 'Limited' access to Restricted Data.

How many people have Q Clearance?

Ever wonder how many people currently have the enigmatic Q Clearance, the required security clearance for access to nuclear secrets? Well, I found out.

blog.nuclearsecrecy.com

Ah, thanks for that!

Frankly, that's a bad training system. If the standard is set at the right level, and everybody passes, that's a success. If you keep having to raise the standard to make sure you fail someone, you're arbitrarily reducing the number of qualified people you have access to.

And equally, if the standard is set at the right level, and everybody fails, that's also a success. You've determined that nobody in that class was suitable for the role.

If you fail the first test, you get extra instruction on what you failed. I think it's failing the retests that get you kicked from program.