Could the UK have done a better job of maintaining an independent strategic nuclear deterrent?

[Yellow Palace]

Well, the missile in the vertical tube did not exactly have onboard reload, so... just have the mechanism to eject the whole launch container from the silo in case of troubles.

With HTP, just flooding the tube would probably deal with the emergency. The standard procedure for HTP going bad is just to add lots of water - diluting the HTP makes it much safer, and the water also takes care of cooling. As storable oxidisers go, it's actually pretty well behaved.

 

[JohnCitizen]

Very very interesting, especially from my POV across the pond. However, in this discussion it seems no distinction is made between collaborative development or shared components w/the US on the one hand and actual employment/concept of operations on the other. In other words, while the Blue-series weapons, for example, may have required some US components, they were very much British weapons that the UK could have employed in any doctrinal way they wanted.

Or put another way, there is a big difference between being "dependent" on the US for certain components of a British weapons system and relying on what is essentially a US weapon system with some British inputs. Skybolt, Polaris, and Trident seem to fit the latter category.

Still, once the UK has enough of US-designed "weapon system X," it can use them pretty much however it wants . . . unless the US attaches some strings to the technology transfer (or the UK has truly limited access to the full production line of "weapon systems X").

The French basically build truly indigenous weapons systems and go from there. The French wanted/want a truly independent deterrent in the sense that its totally autonomous from Washington. Or anyone else. I'd argue that's why UK cooperation w/ the French on nukes didn't really go anywhere.

Its interesting alt-history to consider an anti-US paleo-conservative Tory following Churchill's second act (or in lieu of it all together). I don't think Gaullist-style nuclear independence would be worth the cost in lost strategic cooperation, intel sharing, cultural affinity, but that's just me.

 

[zen]

Do we have to point out the obvious?

UK was working on nuclear weapons until merger with US effort. Pooling knowledge and resources.

Hard as this is to understand, it's not actually possible to disentangle US and UK knowledge on the basics of nuclear weapons.

When the US shut the UK out of this in '45 amongst talk of giving Stalin the rest of Europe and having traded away the very basis of the UK's declared red line with Germany (Poland), it was not unreasonable to assume that we might be alone again in some future war with the USSR.

 

[Scott Kenny]

Very very interesting, especially from my POV across the pond. However, in this discussion it seems no distinction is made between collaborative development or shared components w/the US on the one hand and actual employment/concept of operations on the other. In other words, while the Blue-series weapons, for example, may have required some US components, they were very much British weapons that the UK could have employed in any doctrinal way they wanted.

Or put another way, there is a big difference between being "dependent" on the US for certain components of a British weapons system and relying on what is essentially a US weapon system with some British inputs. Skybolt, Polaris, and Trident seem to fit the latter category.

Polaris and Trident have US rocket motors (and US-designed missile compartments), but with British-designed and built warheads. As far as I know, the UK can launch their missiles without any US restrictions. It's not like the NATO dual-key thing where the US would hold the weapons.

Ask France how expensive designing an SLBM ended up...

Its interesting alt-history to consider an anti-US paleo-conservative Tory following Churchill's second act (or in lieu of it all together). I don't think Gaullist-style nuclear independence would be worth the cost in lost strategic cooperation, intel sharing, cultural affinity, but that's just me.

The US also had a pretty hard Isolationist sweep post-war (again).

 

[JohnCitizen]

Polaris and Trident have US rocket motors (and US-designed missile compartments), but with British-designed and built warheads. As far as I know, the UK can launch their missiles without any US restrictions. It's not like the NATO dual-key thing where the US would hold the weapons.

Ask France how expensive designing an SLBM ended up...


The US also had a pretty hard Isolationist sweep post-war (again).

You're correct, there are no restrictions on British Trident SLBMs (nor were there on Polaris). The British designed & built warheads are His Majesty's property.

Speaking of the dual use program, though, or American bombs in Europe more broadly, the Bulletin of the Atomic Scientists has reported a few times that upgrades to RAF Lakenheath's nuclear weapons "vaults" & associated systems are in the works (along with other European bases). The upgrades could foreshadow the return of B61 bombs to Lakenheath, though these aren't for British use. The upgrades could also be standard modernization, ensuring the base is capable of receiving weapons in the future even if there is no plan to do so.

Increasing Evidence that the US Air Force's Nuclear Mission May Be Returning to UK Soil - Federation of American Scientists

New U.S. Air Force budgetary documents strongly imply that the United States Air Force is in the process of re-establishing its nuclear weapons mission on UK soil.

fas.org

 

[uk 75]

Despite some rocky bits the US UK relationship has held up pretty well right up to the present.
Peter Hennessy's excellent books about the nuclear deterrent and the Royal Navy's submarines make it clear that there was no appetite in the Conservative governments throughout for going it alone like France.
Cost was the main obstacle as ever but also no PM could contemplate using nuclear weapons except in a war also involving the US. The Falklands underscored that with Caspar Weinberger and George Schulz receiving honorary Knighthoods for their roles in helping us.

 

[Dilandu]

When the US shut the UK out of this in '45 amongst talk of giving Stalin the rest of Europe and having traded away the very basis of the UK's declared red line with Germany (Poland), it was not unreasonable to assume that we might be alone again in some future war with the USSR.

Well, the very concept that UK would be able to fight a war against USSR alone was extremely dubious even in 1945. By mid-50s it became painfully obvious that even on sea Britain would not be able to compete with Soviet overwhelming industrial and technological superiority.

 

[uk 75]

The UK has always prefered to fight wars with allies to make up for its own weaknesses. We would not have entered either WW1 or 2 without France supplying the bulk of ground forces.
Postwar we were a founding member of NATO for the same reason.

 

[JohnCitizen]

Despite some rocky bits the US UK relationship has held up pretty well right up to the present.
Peter Hennessy's excellent books about the nuclear deterrent and the Royal Navy's submarines make it clear that there was no appetite in the Conservative governments throughout for going it alone like France.
Cost was the main obstacle as ever but also no PM could contemplate using nuclear weapons except in a war also involving the US. The Falklands underscored that with Caspar Weinberger and George Schulz receiving honorary Knighthoods for their roles in helping us.

"no PM could contemplate using nuclear weapons except in a war also involving the US"

That's so true, though I never quite thought about it so simply! There was not and--as far as I can tell--is not a conceivable scenario in which the UK would use its nuclear weapons but the US wouldn't be involved. However, I think some official MoD line somewhere notes that Britain is an island that once was all alone and has to always be prepared for such a contingency, etc etc The only scenario I can think of, starting under current geopolitical realities, would be more of a case where the bad guys have once again overrun Europe and perhaps the US has made a separate peace with them.

But even that would still fall under the category of a war "involving the US" . . . just in this scenario, the US has checked out!

It's interesting that, because the UK abandoned all types/classes of nuclear weapons but the strategic SSBN/SLBM, there really isn't a scenario other than "Doomsday" (or something close) in which Britain could actually use a nuke.

I realize that for many, especially staunch advocates of the "minimal deterrent" school of thought, that reality may be considered a good thing. It's been over a quarter of a century (wow!) since UK retired the WE.177 and maintained only the SLBMs, so I suppose it long ago became the "new normal" in British strategic thinking that nuclear weapons would cease to effectively have any warfighting purpose.

 

[uk 75]

WE177 was originally developed for independent use by the UK in deployments to the Near East (Cyprus), Gulf, and Far East (Singapore). It was assumed that new nuclear weapons states would need to be deterred without a US presence.
After the 1970s the rationale for a UK weapon is less clear since we were deploying them on behalf of NATO Saceur and Saclant. But since we already had them in service it seemed reasonable to keep them alongside US deployed weapons.
The UK has argued it could use a Trident with small warhead instead but I find this just a sop to politicians. B61 is the NATO tactical nuclear response.

 

[zen]

no PM could contemplate using nuclear weapons except in a war also involving the US

Which can be read in an pro-US, anti-UK way if your biases so run that way.
Or...
You can grasp that we can launch and the USSR will have to launch on NATO and the US.

 

[Yellow Palace]

Polaris and Trident have US rocket motors (and US-designed missile compartments), but with British-designed and built warheads. As far as I know, the UK can launch their missiles without any US restrictions. It's not like the NATO dual-key thing where the US would hold the weapons.

In the case of Chevaline, also a British-designed payload bus - not a full MIRV capability, granted, but the UK demonstrated the ability to build every part of a liquid-propellant IRBM. Integration isn't trivial, and really you'd want solid propellant, but neither of those are massive obstacles.

 

[NOMISYRRUC]

The ALT-Blue Streak SLBM

Development of Blue Streak still begins in 1955 except that it's an SLBM to replace the V-Force in 1965 instead of a MRBM. It wasn't cancelled in favour of Skybolt in 1960 which in turn was cancelled in 1962 by the USA leading to the purchase of Polaris. It entered service on the 4 Real-Resolution class submarines (of 5 planned) that entered service 1967-69 and relieved the RAF's V-Force at midnight on 30th June 1969 - four-and-a-half years late.

Some of the money for the R&D costs came from the £84 million spent on Real-Blue Streak 1955-60, the £32 million spent on Blue Water to 1962 and the £27 million spent on Skybolt to 1962. There would also been the money spent keeping Blue Streak "ticking over" between its cancellation as a MRBM & the start of the Europa project and the money spent on Europa itself. However, that's probably not enough so there's no Blue Steel in this "Version of History" and the money spent on the R&D and production of that stand-off bomb is instead spent on the development of ALT-Blue Streak.

The cost of 4 Resolution class submarines and their support facilities was the same. However, the ALT-Blue Streak missiles probably cost more than the Polaris missiles purchased from the USA. That's in part because the British Polaris missiles were at the end of a production run of 1,409 missiles. Production of the ALT-Blue Streak probably didn't exceed 200 including the missiles fired in the test programme, training rounds, backing rounds and the missiles installed on the submarines. The good news is that they'd be paid for in Pounds Sterling instead of US Dollars which would have helped the Balance of Payments.

ALT-Blue Streak had at least the same performance as Polaris A-3. I want it to be equal to Poseidon C-3. That may be possible on engineering grounds but I'm not sure about the extra cost. One way might be to make it an Anglo-French project to take the place of ELDO/Europa and Concorde. I also want something better than Chevaline which is preferably an equivalent to Trident C-4. However, that's another missile that may be possible on engineering grounds, but is too expensive. Similarly, I'd like a British equivalent to Trident D-5 to arm the Vanguard class.

Can a British equivalent to Polaris A-3 be developed in time to enter service in 1967 & reach full operational capability in 1969 with a start in 1955 and with the money spent on the "Real World's" nuclear armed missile projects? Could the UK have done better than that? Or would it have done worse? Could it have been followed up with equivalents to Poseidon and both versions of Trident without gutting expenditure on conventional forces like France has?

The money spent on Blue Streak, Blue Water & Skybolt was £143 million 1955-62. I don't know how much was spent on keeping Blue Streak "ticking over" between 1960 and the start of Europa. I don't remember how much the UK spent on Europa either, but I think the British contribution was initially 36% and then reduced to 25%.

According to Wynn in "RAF Nuclear Deterrent Forces" the estimated R&D cost of Blue Steel in October 1958 was £35 million plus £150,000 per missile (ex-warhead) which rose in October 1958 had risen to £60 million for the R&D plus £250,000 per missile (ex-warhead). On 17.05.61 the costs were £60 million for the R&D and £21 million for production; of that total £44 million was spent or committed. According to Wood £825,000 was spent on Blue Steel Mk 2 to December 1959. That's a total of £82 million.

That increases the total spent 1955-62 to £225 million which at the prevailing exchange rate of 2.8 USD to One GBP was $630 million or for the benefit of @Archibald & people making (valid) comparisons to the contemporary French SNF programme 3,110 French Francs.

From memory the 4 British Polaris submarines cost £160 million (sans missiles) out of a total of around £400 million 1962-70. At contemporary exchange rates that's 448 million USD and 2,212 for the submarines (sans missiles and 1,120 million USD & 5,530 million French Francs. My guess is that four British SSBNs built in my timeline would cost £160 million (sans missiles) regardless of whether they were armed with Polaris A-3 missiles or a British equivalent. Similarly the British designed & built warheads on a British SLBM would have cost the same as the British designed & built warheads on the Polaris A-3 missiles that armed the real Polaris submarines.

In my "Version of History" there isn't a TSR.2 because the RAF is forced to buy Buccaneers (which had a half-decent engine from day one) because the RAF is forced to buy the Buccaneer. Thus the £195 million spent on TSR.2 to 1965 and the £46.4 million spent on F-111K to January 1968 which is a total of £241.6 million (676 million USD or 3,337 million French Francs) if the cost of the British SLBM was much as some think (and it may well have been) this money is available if necessary by limiting the number of Buccaneers built to "Real World" numbers.

In my "Version of History" 400-odd Spectres (the British Phantom equivalent & excluding prototypes) were built instead of 250-odd Lightings and 150-odd Sea Vixens (excluding prototypes). There would have been a Spectre Mk 2 which would have been built instead of the P.1154 & Spey-Phantom. As far as I know £21 million was spent on P.1154 1962-65 and the R&D cost of Spey-Phantom was some £100 million for a total of £125 million (350 million USD or 1,728 French Francs). There's also the production cost of the 170 Spey-Phantoms. Again, if the cost of the British SLBM was as much as some think (and it may well have been) the money spent on the P.1154 and Spey-Phantom is available and the RAF & RN will have to make do with the Spectre Mk 1 until replaced by the Tornado and (probably) the Hornet in the RAF & RN respectively.

In my "Version of History" a transport aircraft called the Hawker Siddeley Middlesbrough is built instead of the Blackburn Beverley, Armstrong Argosy, HS.681 and Lockheed C-130K Hercules. It's called the Middlesbrough because I'm from Teesside and is a British equivalent to the C-130 Hercules with engines in the Proteus/Clyde or the Orion/Tyne classes. There would be a Mk 1 built instead of the Beverley, a Mk 2 built instead of the Argossy and a Mk 3 built instead of the HS.681 & C-130K. Once again, if the cost of the British SLBM was as much as some think (and it may well have been) the money spent on the Middlesbrough Mk 3 is available and the RAF will have to make to with the Middlesbrough Mk 1 & 2 aircraft built instead of the Beverley & Argosy.

There isn't a Concorde in my "Version of History" and my figures are that the total cost (to France & the UK) was £1,134 million for the R&D and £654 million production costs of which £278 million was recovered from the airlines. My plan was to spend the UK's share of that money subsidising the British airliner manufactures so they could drive Boeing or Douglas out of the large airliner business. However, if necessary the portion of that which was spent before 1970 could be spent on the British Polaris A-3 analogue and the money spent afterwards could be combined with the money spent on Chevaline to produce something better than Chevaline.

Finally, alternative history isn't necessarily a zero-sum-game. My guess is that the better managed British aerospace industry of my "Version of History" results in a stronger British economy. I want the MoD's share of that extra wealth to be spent on the RN

***** ***** ***** ***** ***** *****​

Interestingly, the original requirement was for 75 Blue Steel stand-off bombs to support a UE of 64 (i.e. 8 squadrons of 8 V-bombers) plus training round and 64 happens to be the number of Polaris (and then Trident 2) missiles aboard the 4 Resolution (and later Vanguard) class submarines.

***** ***** ***** ***** ***** *****​

As comparisons between my British SLBM programme have been made with the French SSBS programme these are the costs that I have it which come from the Encyclopaedia Britannica Books of the Year in Middlesbrough Reference Library, because the internet didn't exist at the time I made the notes from said books.

According to the Book of the Year 1961 (Events of 1960).

• NF 9,500 million [687 million GBP or 1,924 million USD] was to be spent on the Strategic Nuclear Force 1960-64.
• NF 4,000 million [270 million GBP or 1,025 million USD] was to be spent on the uranium isotope plant at Pierrelatte.
  • And.
• 3 atomic bombs were tested in the Sahara Desert and Events of 1961 said a 4th bomb was tested in April 1961.
• 50 Mirage IV were planned.
• There were plans for SSBNs and a nuclear reactor was under development.

[My guess is that the UK wasn't spending money building an equivalent to Pierrelatte because it already had Windscale.]

According to the Book of the Year 1963 (Events of 1962).

• The first Mirage IV squadron would become operational during 1963.
• Hydrogen bombs with a ballistic missile delivery system would be operational by 1970.
• The costs were still NF 9,500 million 1960-64 for the SNF and NF 4,000 million for the uranium isotope separation plant at Pierrelatte which would be operational in 1966. [Meanwhile, No. 1 pile at Windscale became operational in 1950.]
• The USA offered Polaris to France on the same terms as the UK.
• There was to be one KC-135F for every 4 Mirage IVs.

According to the Book of the Year 1964 (Events of 1963).

• The Intervention Force of 6 divisions (including one airborne-amphibious division) were to have tactical atomic weapons by 1970.
• The first of 50 Mirage IV were to become operational in the winter of 1963-64 with deliveries continuing to 1966.
• They were to be replaced by 3 SSBN.

According to the Book of the Year 1965 (Events of 1964).

• Nuclear Expenditure was 25% of the French Defence budget.

According to the Book of the Year 1966 (Events of 1965).

• A force of 30 IRBM & 3 SSBN was planned for the 1970s to replace 60 Mirage IV & their supporting KC-135Fs.
• The first SSBN was to be launched in 1967 and be operational in 1969.

According to the Book of the Year 1967 (Events of 1966).

Stage 1 - 62 Mirage IV by the end of 1966 - 50% on 24 hour alert at 12 air bases.​

Stage 2 - 25 MRBM (not IRBM) for completion 1969-72.​

Stage 3 - 3 SSBN for completion 1969-72.​

• The Defence Budget was 4.6% of GNP.
• [The British Defence budget was about 7.0% of a larger GNP at this time.]
• The French SNF was absorbing 21.8% of the French Defence Budget.
• [As far as I know the British Defence budget was larger.]
• Pierrelatte became operational in the spring of 1967, several months ahead of 1967.
• [No. 1 pile at Windscale became operational in 1950.]
• The French Army was to receive French tactical nuclear weapons beginning in 1971 and it was to have 200 warheads by 1975.

According to the Book of the Year 1968 (Events of 1967) development of the French SNF was to be in 3 stages.

Stage 1 - Completed 1967 - 62 Mirage IV and 12 KC-135F.​

Stage 2 - Construction of 25 IRBMs for completion 1969-70.​

Stage 3 - 3 SSBNS for completion 1972.​

​

According to the Book of the Year 1969 (Events of 1968).

• Due to delays the 50 Mirage IVs would have to be retained until 1975.
• The 27 IRBMs planned for 1971 would not be ready until the middle 1970s.
• The 4 SSBNs planned by the middle 1970s were also expected to be delayed.

According to the Book of the Year 1970 (Events of 1969).

• 4 SSBN were planned for 1970-75.
• 5 Divisions were to receive Pluton by 1976. Service entry had been planned for 1974 - See Events of 1966.
• 27 IRBM likely to be made obsolete by ABM and MIRV improvements by the time of their IOC.

According to the Book of the Year 1970 (Events of 1969) the cost overruns on the French SNF were.

• 83% on the second SSBN meaning the postponement of the first SSN.
• 75% on the IRBM leading to the cancellation of the third squadron.
• The first SSBN to enter service in 1971 instead of 1969.

 

[Archibald]

Mirage IVA IOC was October 1964 at Mont-de-Marsan Base Aérienne 118. Order of battle below

https://www.escadrilles.org/histoire-armee-de-l-air/armee-de-l-air-1975/

Unités de Bombardement fin-1975

Escadron		Avion(s)	Base
EB 1/91 Gascogne		Mirage IVA	Mont-de-Marsan
EB 2/91 Bretagne		Mirage IVA	Cazaux
EB 3/91 Beauvaisis		Mirage IVA	Creil
EB 1/92 Bourgogne		Vautour	Mérignac
EB 2/92 Aquitaine		Vautour	Mérignac
EB 1/93 Guyenne		Mirage IVA	Istres
EB 2/93 Cévennes		Mirage IVA	Orange
EB 3/93 Sambre		Mirage IVA	Cambrai
EB 1/94 Bourbonnais		Mirage IVA	Avord
EB 2/94 Marne		Mirage IVA	St-Dizier
EB 3/94 Arbois		Mirage IVA	Luxeuil

Unités de Ravitaillement en Vol fin-1975

ERV 4/91 Landes		C-135F	Mont-de-Marsan
ERV 4/93 Aunis		C-135F	Istres
ERV 4/94 Sologne		C-135F	Avord

This was the climax of the Mirage IVA force, in 1975. Immediately thereafters it was drastically pared down until the ASMP decision in 1978, that modernized 19 airframes (one Mirage crashed so 19 rather than 18 had to be upgraded).

 

[Archibald]

Mirage IVA & C-135FR were, indeed, an interim nuclear vector system. Coming on their heels was a) Plateau d'Albion IRBMs and b) Redoutable class submarines with SLBMs. Both took alert in 1970-71.

Other "nuclear goodies" developed in parallel were tactical weapons: Pluton missiles on AMX-30 chassis for the army and AN-52s for Mirage IIIE and the coming Jaguar. They both made live drops at Moruroa one year apart: in 1973 and 1974. The only other live air drop was a Mirage IVA dropping an AN-11 in July 1966. All others atmospheric tests at Moruroa were either barge or balloon, and eventually underground after 1974.

 

[Archibald]

As for the British missile: yeah, Black Archer, baby. Long story short, there were many different diameter for H2O2/kerosene british rockets: Black Knight 36 inch was too small, but 54 inch and 72 inch were feasible... and the end result was Black Arrow that could hit orbit with three stages, so - could have been an ICBM.
The baffling irony with British missile is that the cruise missile - Blue Steel- uses a H2O2/kerosene indigenous rocket engine; but the IRBM - Blue Streak - is 100% different, american design with kerolox engines.
In a sane world, Blue Streak should have been a member of the extended Blue Steel / Black Knight / Black Arrow family of Gamma rocket engines burning keroxide (kerosene + H2O2). This is exactly what David Andrews at H.S proposed twice or thrice, 1958-1961: and what I called Black Archer.
Unlike Blue Streak, Black Archer is compact enough with no LOX so could in theory be made into a SLBM.

 

[NOMISYRRUC]

Link to Post 54.

I think you're missing the point about the last half of Post 53. I was trying to give a scale of the British SLBM programme in comparison with the French SNF programme. In particular what I know about the latter's costs.

I think the extra costs are the R&D and production of the ALT-Blue Streak missile, because the UK built and paid for the SSBNs and the warheads anyway as part of the Polaris programme. Also the cost of the Polaris missiles can be deducted from the production cost of the ALT-Blue Streaks.

Though for the record.

While France had a front line of 36 Mirage IVs in 9 squadrons of 4, supported by 12 KC-135Fs the UK had a front line of 88 Victor & Vulcan Mk 2s (out of 123 that were built) in 11 squadrons of 8 aircraft which were supported by a front line of 16 Valiant tankers in 2 squadrons and then 24 Victor Mk 1 tankers (out of 31 that were converted) in 3 squadrons. Furthermore, 40 of the 88 third-generation V-Bombers were armed with Blue Steel Mk 1. Enough were built for 48 in 6 squadrons, but the third Victor Mk 2 squadron replaced the Valiant LRPR squadron instead of becoming the sixth Blue Steel squadron.

The RAF's V-Force wasn't disbanded when the RN's Polaris submarines relieved it in mid-1969. Instead 32 Vulcans (4 squadrons) were transferred to the SACEUR role where they belatedly relieved the 24 Valiants (3 squadrons) which were retired in 1965 and 16 Vulcans (2 squadrons) were transferred to Cyprus where they replaced 32 Canberra bombers (4 squadrons). The squadrons in Cyprus returned to the UK as part of the Mason Defence Review of 1974-75 and the 48 Vulcans (6 squadrons) remained in service until the early 1980s when they were replaced by the Tornado.

Meanwhile, a seventh Vulcan bomber squadron was converted to a LRPR squadron to replace the Victor SR.2 squadron and the 29 surviving Victor Mk 2s were to be converted to tankers to replace the 31 Victor K Mk 1s virtually one-to-one. But the number of tanker squadrons was cut from 3 to 2 as part of the Mason Defence review and the number of aircraft converted to Victor K.2s was cut to 24.

 

[alertken]

NOM's Q, doing better, presumes sufficient political will to spend even more £ than OTL. He speaks only of Deterrence, so we don't need to address Blue Water SRBM, MADMs, NDBs, Ikara torpedo-thrower, cannon shells...he means Counter Value.
So he is asking: could no lower a scale of Assured Destruction have been better secured...for better let us assume: cheaper and/or more likely to penetrate in volume.
To which the A is clearly Nyet because everything we did was subsidised by US...so if we tried to do something entirely solo...however better it might have been, it could not have been cheaper. That's why posts have centred on Anglo-French...but ignore JC's#42 point: JFK offered SSBN/SLBM to UK and to CDG, who declined, to preserve virginity: why would he favour UK, who had nothing better to offer?

PM Attlee's purpose, 1/47, in copying Fat Man and diverting much Aero from $ exports to the nugatory economics of Big British Bombers, was to deter Stalin from adventures after the 1948 Republican President Brought the Boys Home from W.Germany. Stalin torpedoed that in Berlin, 23/6/48....so there's a Fun Whiff.
WSC then tried to use his personal Special Relationship with Ike, Allies in Korea v PRC/Stalin proxy, to secure US AW Articles, so avoiding great spend. Failing, he initiated Red Beard fission Bomb, the Medium Bomber Force, an MRBM, a supersonic Bomber and a Bigger Bang.

Wow!

His successors knew that lot was unaffordable, uncrewable, inoperable and some/many/all would be fraught. Oh yes!

One, and only one option survives the correctness of the actual kit deployed to meet the politically-afforded Task (waypaving in US collaboration, or solo-delivered Unacceptable Destruction, reducing in maturity from 20 cities to one): GLCMs: a UK Tomahawk, now Storm Shadow, somewhere around 1990, so replacing Trident-on-SSBNs. Launched from SSNs/SSKs (which must anyway be bought for the conventional interlude), or from loitering long endurance a/c, which also have ECM etc roles.

That was derided as Liberal-feeble so likely to create insufficient rubble. How much is Enough?

 

[NOMISYRRUC]

Mirage IVA & C-135FR were, indeed, an interim nuclear vector system. Coming on their heels was a) Plateau d'Albion IRBMs and b) Redoutable class submarines with SLBMs. Both took alert in 1970-71.

Other "nuclear goodies" developed in parallel were tactical weapons: Pluton missiles on AMX-30 chassis for the army and AN-52s for Mirage IIIE and the coming Jaguar. They both made live drops at Moruroa one year apart: in 1973 and 1974. The only other live air drop was a Mirage IVA dropping an AN-11 in July 1966. All others atmospheric tests at Moruroa were either barge or balloon, and eventually underground after 1974.

From memory each SSBS squadron had 10 missiles consisting of one spare and 9 operational missiles. That accounts for some of the discrepancies in the figures that I gave in Post 53. I've read elsewhere that the plan was for 50 SSBS (45 operational and 5 spares) in 5 squadrons, but as we know cost overruns reduced the number deployed to 20 SSBS (18 operational and 2 spares) in 2 squadrons.

Also the Pluton missile was produced in smaller numbers than originally planned too. From memory 120 were originally planned, which was then cut to 30 and then to 25. However, that might have been because it was made obsolete by revised operational requirements rather than cost overruns. Interestingly, 120 Hadès missiles (Pluton's replacement) were planned too if its Wikipedia article is to be believed.

@Archibald as far as I know MSBS, SSBS and the supporting Precious Stones missiles were begun in 1960. Is that correct? If it is the ALT-Blue Streak had a half-decade head start over the MSBS. In my "Version of History" the plan in 1955 was that it would relieve the V-Force in 1965, but due to the usual delays doesn't assume the UK's strategic nuclear deterrent role until mid-1969.

 

[Archibald]

@Archibald as far as I know MSBS, SSBS and the supporting Precious Stones missiles were begun in 1960. Is that correct?

Yes. De Gaulle came back in May 1958, decided to go all out on independant nuclear deterrent, and first move (1958-1961, roughly) was to secure Mirage IVA as an early interim system.
Rockets / missiles came a little later, technology evolved at the speed of light, Minuteman & Polaris clearly showed the way but France was rebuked when asking for their tech - or only as dual-key, MLF as pushed by the two Deans - Rusk and Acheason.

Nota Bene; France atempt(s) to get Polaris outside MLF were not as dramatic as the Nassau crisis and agreement, but it happened nonetheless.

Kennedy and the Deans tried to bait France with MLF, because cheap Polaris vs Force de Frappe insane costs (also Skipjack nuclear attack subs). But De Gaulle did not liked the proposal. Better pay an arm and a leg (and perhaps a testicle) to Force de Frappe rather than MLF - that was the motto.

 

[NOMISYRRUC]

Another question for @Archibald.

There's no Concorde in my timeline. What does France do with its share of the money? According to what I have the total cost (to France & the UK) was £1,134 million for the R&D and £654 million production costs of which £278 million was recovered from the airlines.

 

[Archibald]

Another question for @Archibald.

There's no Concorde in my timeline. What does France to with its share of the money? According to what I have the total cost (to France & the UK) was £1,134 million for the R&D and £654 million production costs of which £278 million was recovered from the airlines.

Impact of Advanced Air Transport Technology

books.google.fr

$3.25 billion for Concorde, in 1980 dollars. I had found $2 billion something, in other sources: so it makes some sense.

As to what France would do with half of that money - no idea. I think it would stay with civilian aerospace projects, so either Diamant or Europa, CNES and ELDO.
Or maybe to a civilian airliner, but Dassault Mercure was an even more miserable, pathetic commercial failure than Concorde.

 

[NOMISYRRUC]

As to what France would do with half of that money - no idea. I think it would stay with civilian aerospace projects, so either Diamant or Europa, CNES and ELDO.

Fair enough. However, there can't be an ELDO as we know it, because there was no Real-Blue Streak to use as the first stage of Europa. Furthermore, the UK isn't part of ELDO in my timeline because the money's spent on the British SLBM project.

 

[NOMISYRRUC]

Impact of Advanced Air Transport Technology

books.google.fr

$3.25 billion for Concorde, in 1980 dollars. I had found $2 billion something, in other sources: so it makes some sense.

$3.25 billion = £1.398 billion at 1980 exchange rates and FF 13.733 billion at 1980 exchange rates.

Another question for @Archibald.

There's no Concorde in my timeline. What does France do with its share of the money? According to what I have the total cost (to France & the UK) was £1,134 million for the R&D and £654 million production costs of which £278 million was recovered from the airlines.

• My costs are £1,134 million + £654 million = £1,788 million - £278 million = £1,510 million or £1.510 billion.
• Your £1.398 billion is similar to my £1.510 billion.

How much of Plan Bleu or how many Mirage G.8s would your half have bought? Or would the French Government spend it on getting the first SSBNs in service on time and the 3 cancelled SSBS squadrons? Or would they have spent it on accelerating the development of M-2, M-20, M-4 and M-45?

 

[zen]

To which the A is clearly Nyet because everything we did was subsidised by US...

What a history blind statement!

solo...however better it might have been, it could not have been cheaper.

Assumption, not based on facts. Essentially an opinion.

Failing, he initiated Red Beard fission Bomb, the Medium Bomber Force, an MRBM, a supersonic Bomber and a Bigger Bang.

Correct decision.

His successors knew that lot was unaffordable, uncrewable, inoperable and some/many/all would be fraught. Oh yes!

False.
His successors chose other priorities.

On cruise. Inadequate unless at scale....much greater scale = much greater cost.

Liberal sentiments.....defeatist, declinist, luxury beliefs for Anywhere people.
The Foxes must always make way for the Lion.

 

[NOMISYRRUC]

I strongly doubt that. Polaris development was a money sink beyond all money sinks.

In defence of my SLBM programme . . .

Polaris was a crash programme. It went from nothing in September 1955 to George Washington commissioning on the penultimate day of 1959, the completion of 40 additional boats by 1967 and the production of 1,409 missiles which were built in 3 marks. The number of SSBNs built for the RN in both "Versions of History" was literally a tithe of that and the number of missiles would be a fraction of that as there would only be the R&D rounds plus enough to support the Unit Equipment (UE) of 64 missiles aboard the 4 SSBNs.

My SLBM programme was an altogether more sedate and low scale affair. It starts in 1955 because that's when development of the Real-Blue Streak began and at that time it was planned to enter service in 1965 but like the Real-British Polaris submarines the ALT-Resolution class they didn't enter service until 1967-69 and relieve the V-Force in mid-1969.

Interestingly the average cost of the 31 Laffayette class SSBNs was $110 million according to Jane's 1968-69 and if I remember correctly the four Resolution class cost an average of £40 million each (without missiles) which at the 1968 Exchange Rate of 2.4 USD to 1.0 GBP = $96 million.

As I've written a few times in this thread the 4 British SSBNs aught to cost the same regardless of whether they were armed with Polaris or ALT-Blue Streak. I've also written before that the cost of the British designed & built warheads for a British equivalent to Polaris A-3 aught to cost no more than the British designed & built warheads on the Polaris A-3 missiles purchased from the USA in the "Real World".

As I've also written a few times in the thread the imponderable is the R&D cost of the missile and the production cost of the missile from which the cost of the 70-odd missiles that as far as I know were purchased by the UK. I've also written several times in this thread that considerable sums were spent on cancelled strategic weapons projects in the "Real World" (Real Blue Streak et al) and the Blue Steel stand-off-bomb which many people think was a waste of money. There's also the money that the UK spent on Concorde in this "Version of History" and I'm prepared to sacrifice the RAF's Buccaneers (built instead of TSR.2), the RAF & RN's Spectre Mk 2s (built instead of P.1154 & Spey Phantom) & the Middlesbrough Mk 3 (instead of HS.681 & C-130K Hercules). All of which I explained at greater length in Post 53.

 

[NOMISYRRUC]

Look at what happened with the Force d'Frappe, eating the entire defense budget alive and demanding seconds!

I did. Fortunately, there are several things in Britain's favour.

• Despite the UK's economic problems (and despite France enjoying the middle third of its Thirty Years while ALT-Blue Streak was under development) the UK was still richer than France (it wouldn't overtake the UK until the 1970s) and although I haven't checked the UK was probably spending a bigger percentage of a bigger GNP than France on defence in the 1960s.
  • Therefore, there's more defence budget to be eat alive.
• The UK starts its SLBM programme 5 years before France so the cost is spread over about 15 years instead of about 10.
• The UK had a bigger nuclear arms industry in 1955 (when development of ALT-Blue Streak began) than France had in 1960 (when development of MSBS & SSBS began) due to the British having had a nuclear weapons programme since the late 1940s.
  • Therefore, reduced "start up" costs.
• As I've written several times before the Resolution class SSBNs will cost the same whether they're armed with Polaris or a British equivalent.
  • So will the warheads on the missiles.
• The British aren't developing and producing an equivalent to Mirage IV. They already have 330-odd V-bombers.
  • Before you say TSR.2 there isn't one in my timeline because the RAF is forced to buy Buccaneers.
  • However, as also written in other posts I'm prepared to limit British Buccaneer production to the 200-odd (including prototypes) built in the "Real World" and sacrifice the Spectre Mk 2 and Middlesbrough Mk 3 if necessary.
• There isn't a British equivalent to SSBS.
• There isn't a British equivalent to Pluton.

 

[Dilandu]

The money spent on Blue Streak, Blue Water & Skybolt was £143 million 1955-62. I don't know how much was spent on keeping Blue Streak "ticking over" between 1960 and the start of Europa. I don't remember how much the UK spent on Europa either, but I think the British contribution was initially 36% and then reduced to 25%.

As I mentioned above, money is not that much of a problem as total lack of any rocketry experience in UK and inability due to limited resources to adopt a high-risk solutions.

 

[Dilandu]

My SLBM programme was an altogether more sedate and low scale affair. It starts in 1955 because that's when development of the Real-Blue Streak began and at that time it was planned to enter service in 1965 but like the Real-British Polaris submarines the ALT-Resolution class they didn't enter service until 1967-69 and relieve the V-Force in mid-1969.

Look, the problem isn't the pace. The problem is, that UK by 1955 did not have any serious rocket experience and did not have any ballistic missiles to start with. The Royal Navy in 1955 is still not interested in being any part of nuclear warfare, and have literally no missiles at all. And Britain is still unsure about the possibility of making miniature warhead.

Essentially you are trying to launch several major programs in not interconnected spheres; shipborne ballistic missile, missile-carrying submarine, precise guidance system, compact fusion warhead. All those programs for 1955 Britain are high-risk, no experience. If any of them failed, then the others would too.

 

[Dilandu]

As I've written several times before the Resolution class SSBNs will cost the same whether they're armed with Polaris or a British equivalent.

No they wouldn't, because they wouldn't be equivalent. UK missikes would almost certainly be liquid-fueled, since its just more realistic from 1950s than solid fuel. And UK did not have resources of US to switch to solid fuels quickly.

 

[zen]

Hang on we went through this on my thread and those with the knowledge were pretty certain the solid rocket technology was within UK grasp if it was chosen.
It's ultimately just adding more aluminium....

We know that a 42" press was slated for funding and production for a nuclear delivery system.
Talk being of getting to 750nm range, then 1,000nm and then 1,500nm. Ultimately 2,500nm or greater.

We know that it's not beyond the UK science to concieve of and develop small warheads, that discussion did happen I think '56 which is just a year after Edward Teller has indicated such in the US.

We know that the UK RV and safety research efforts were also ahead of the US. It certainly horrified Aldermaston when they got a look at the latest US nuclear weapons designs after '58.

The chief issue is actually precision gyros and their production.

We know Nuclear Submarines were being studied from 1947 and work on shock loads was actually ahead of the US in this period.

The main AH question on subs is whether the UK perseveres with liquid metal reactors or follows the US on Pressurised Water reactors.

We even know that the UK PWR-1 was only late not unresolve-able, when we bought a single US reactor to speed the first SSN into testing and trials.

We'd reused the HTP Submarine experience for chasing high speed subs and tactics needed. Likely an influence on ASW from the late 50's.

So with a small amount of luck and a modest increase in funding and focus. Solid SLBM and SSBN systems packaging Sovereign Nukes along the lines of Acorn are very possible by '65 to '67.

 

[NOMISYRRUC]

The only costs for Polaris that I found on the internet were here.

Polaris

Polaris

www.astronautix.com

R&D $2,231.9 million which at contemporary exchange rates was.

£797.1 million, say £800 million.​

FF10,003 million, say FF 10,000 million.​

Recurring Price $2.813 million in 1965 Dollars, which at contemporary exchange rates was.

£1.00 million​

FF13.87 million​

Flyaway Cost $1.460 million at 1961 prices, which at contemporary exchange rates was.

£0.52 million​

FF7.20 million​

It also says that 1,092 Polaris missiles were made, which consisted of 87 development missiles and 1,005 production missiles. This is considerably less than the 1,409 which I quoted earlier in Post 3 which came from Bill Gunston's rockets & missiles encyclopaedia.

I've looked through the costs of Blue Steel, Blue Streak & Skybolt from the notes I made from Wynn's book about the RAF Nuclear Deterrent Forces to see if there's anything I can use for comparison.

• Blue Steel
  • £60 million for the R&D plus £250,000 million (ex-warhead) per missile in October 1960.
  • £60 million for the R&D plus £21 million for the production on 17.05.61.
  • Both were on a run of 57 rounds (48 UE, 5 backing & 4 proof) and 20 training rounds.
• Blue Streak
  • December 1957 - The IOC was expected in 1963 and FOC was expected in 1965.
  • Early in 1958.
    • 23 test firings to the end of 1963 and it was proposed to increase this to 35.
    • The R&D bill was expected to reach £160 million.
  • At 18.11.58.
    • £200 million R&D + £280 million production & deployment = £480 million.
    • IOC 1965 and deployment of 100 rounds by 1970.
  • No dates.
    • The cost of the underground silos had risen from £2.00 million to £2.88 million per site without missiles.
    • There were 2 missile per site so 50 sites were required for 100 missiles.
    • 50 x £2.00 million = £100 million.
    • 50 x £2.88 million = £144 million.
      • Correction, according to the information from C.N. Hill's book it was one missile per site so the costs were.
        • 100 x £2.00 million = £200 million.
          • Enough to pay for 5 Resolution class submarines without missiles.
        • 100 x £2.88 million = £288 million.
          • Enough to pay for 7 Resolution class submarines without missiles.
    • The prototype site was to cost £4.7 million.
  • In November 1959 the total cost was estimated at £500 million for 60 missiles.
  • At 31.01.60 the firing date for round R1 was scheduled for October 1960.
• Skybolt
  • 20.06.60
    • 144 missiles with spares and associated equipment would cost between £76 million and £115 million depending upon the cost of the missile with a Dollar content of £108 million.
    • That's £0.53 million to £0.80 per missile
  • 1962.
    • The UK continuing Skybolt development was estimated at £310 million (£250 million R&D & £60 million production) over 8 years to 1970.
    • That's £2.15 per missile including the R&D cost and £0.42 per missile without the R&D cost, both on a run of 144 missiles.
    • Pandora would cost £100 million to develop over 8 years.
    • £100 million was saved by the cancellation of Skybolt. As £27 was spent at cancellation means a total cost of £127 million, which seems to low as the estimated total cost in June 1960 was £310 million.

I thought Wynn had estimated production & unit costs of the Blue Streak missiles themselves as well. However, I didn't put them in my notes if he did.

 

[Scott Kenny]

One, and only one option survives the correctness of the actual kit deployed to meet the politically-afforded Task (waypaving in US collaboration, or solo-delivered Unacceptable Destruction, reducing in maturity from 20 cities to one): GLCMs: a UK Tomahawk, now Storm Shadow, somewhere around 1990, so replacing Trident-on-SSBNs. Launched from SSNs/SSKs (which must anyway be bought for the conventional interlude), or from loitering long endurance a/c, which also have ECM etc roles.

That was derided as Liberal-feeble so likely to create insufficient rubble. How much is Enough?

Okay. Tomahawks/equivalent range cruise missile. 1500nmi reach. This means that whatever is carrying this SLCM, the sub needs to get very close to the Soviet coast. This means in the Baltic or Black Seas, or working up north past the Scandanavian Peninsulas to sit off the coast of Arkhangelsk.

Ignoring the extreme vulnerability of being that close to Soviet land based ASW, and ignoring the illegality of sneaking a submarine into the Black Sea (subs can legally only transit the Dardanelles and Bosporus while surfaced which makes it very obvious if/when someone sends a sub into the Black Sea; plus all the mixed fresh and salt water layers makes it really dangerous to even attempt to thread the straits submerged), it takes a long time to get from the home port in the UK to those alert areas.

Which means you effectively need one sub in each alert area, and at least one more sub en route to each alert area (with the attending equal numbers of subs coming back from the alert areas). Plus subs plural in refit getting ready to go out to sea. At a minimum, each alert area requires 4 subs, which cannot go do SSN things when they're doing Strategic Deterrent Patrols, basically because they're not in the right places physically and need to be hiding so they're not found if they're on the way to the alert area.

Three alert areas means a minimum of 12 submarines that are also not available to do SSN jobs. And that rotation is assuming dual crews per SSGN, same as the SSBNs operated, so that they can quickly refit and send the submarine back out to sea without completely wrecking the crew.

So instead of 4x SSBNs and 8x crews, you need 12x SSGNs with 24x crews only slightly smaller than those of the SSBN (~15-20 fewer people)...

Yes, I'm absolutely certain that would save money. [/sarcasm]

As I mentioned above, money is not that much of a problem as total lack of any rocketry experience in UK and inability due to limited resources to adopt a high-risk solutions.

I'm going to assume that the UK had sufficiently good engineers as to make "miniature" sized nukes by 1963 or so.

Guidance and rocket engines are definitely areas where the British were well behind everyone else.

No they wouldn't, because they wouldn't be equivalent. UK missikes would almost certainly be liquid-fueled, since its just more realistic from 1950s than solid fuel. And UK did not have resources of US to switch to solid fuels quickly.

Okay, let's use the example of the US Jupiter missile, since it's the same era and is liquid fueled.

Jupiter is 18.3m/60ft long and 2.67m/8'9" in diameter, weighs a good 50mt/110klbs. It's carrying a W49 warhead that weighs 740kg/1640lbs and has a yield of 1.44MT. Range kinda sucks with that heavy warhead, only ~2500km.

Now, instead of that W49, let's stick a Polaris-sized warhead on it. The Polaris used a W47 warhead that weighed 330kg/733lbs with a yield of 1.2MT. That should be enough of a weight drop to get the "Juparis" to reach 4600km, same range as Polaris.

Make no mistake, Jupiter is a freaking huge missile from a submariner's point of view. It's some 50cm/20" bigger in diameter than Trident 2, and at least 4.5m/15 feet longer.

But it would fit into a submarine if you allowed a tall turtleback like on the Soviet Delta-class (Project 667 class) and a hull diameter of about 12.3m/40ft. And once you have submarines with that big a hull and missile tubes, when you develop good solid fuels and even lighter warheads, you get a really capable missile.

 

[NOMISYRRUC]

Questions for @Scott Kenny & @zen.

• Apart form the solid-fuel engines how much harder is a SLBM to develop than a MRBM?

 

[zen]

Questions for @Scott Kenny & @zen.

• Apart form the solid-fuel engines how much harder is a SLBM to develop than a MRBM?

The main unique problem is launch via a gas bubble enveloping the missile as it moves upwards through the water. This is not beyond UK theory or scientific development, but it is more cost.

If anything the Navy and marine cavitation research is quite competent.

Otherwise this is no difference in solid rocket engines.

 

[NOMISYRRUC]

Estimated cost of Blue Streak at 1959 from Page 85 of "A Vertical Empire" by C.N. Hill.

• £200 million for 100 sites at £2 million per site.
  • Which would buy 5 Resolution class submarines without missiles.
• £50 million for 100 missiles at £0.5 million per missile.
  • The recurring cost for a Polaris missile in 1965 was £1.00 million.
  • The flyaway cost for a Polaris missile in 1961 was £0.52 million
• £125 million operating costs at £0.125 million per missile per year.
• £160-£200 million R&D.
• £100 million warheads.
  • That's £1 million per warhead.
  • Which increases the cost of each missile to £1.5 million.
• Total £635-£675 million
  • Even with 60 missiles deployed, which would have been the final total, these were impressive sums for 1959.

The licences on the Convair Atlas ICBM and Rocketdyne S-3 saved a great deal of time. I though he gave an estimate of how much time. However, I couldn't find it when I skimmed through the chapter on Blue Streak. As far as I know licences for Polaris & its solid-fuel engines couldn't be purchased from Lockheed & Aerojet because they hadn't developed the technology to sell licences for in 1955.

 

[Scott Kenny]

Hang on we went through this on my thread and those with the knowledge were pretty certain the solid rocket technology was within UK grasp if it was chosen.
It's ultimately just adding more aluminium....

We know that a 42" press was slated for funding and production for a nuclear delivery system.
Talk being of getting to 750nm range, then 1,000nm and then 1,500nm. Ultimately 2,500nm or greater.

Anything short of 1000nmi might as well stay as a technology demonstrator.

We know that it's not beyond the UK science to concieve of and develop small warheads, that discussion did happen I think '56 which is just a year after Edward Teller has indicated such in the US.

We know that the UK RV and safety research efforts were also ahead of the US. It certainly horrified Aldermaston when they got a look at the latest US nuclear weapons designs after '58.

Got a book recommendation I can read on that?

The main AH question on subs is whether the UK perseveres with liquid metal reactors or follows the US on Pressurised Water reactors.

That answer should have been self-obvious: how do you keep molten sodium from leaking into your secondary steam loop?

You don't. You can't. So you go with a PWR, which has a lot of other advantages to it, like how the Navy knows boiling water.

Edit: There's a reason that USS Seawolf SSN575 had her liquid metal reactor ripped out at the first refueling!

We even know that the UK PWR-1 was only late not unresolve-able, when we bought a single US reactor to speed the first SSN into testing and trials.

That is certainly not how I was told that ended up. There's supposedly a lot of S5G in the PWR-1, the US shipped one S5G plant and a full set of blueprints over.

 

[NOMISYRRUC]

The main unique problem is launch via a gas bubble enveloping the missile as it moves upwards through the water. This is not beyond UK theory or scientific development, but it is more cost.

If anything the Navy and marine cavitation research is quite competent.

Otherwise this is no difference in solid rocket engines.

Thank you.

I asked the question because the R&D cost of Polaris on Astronautix.com was £800 million and the money available from Blue Steel, Blue Streak, Blue Water & Skybolt is £225 million 1955-62 about a quarter of the amount required. But there's also the money spent on Blue Streak after 1960 as part of the Europa programme, plus as I've already written the money spent on Concorde and the C-130K, F-111K, HS.681, P.1154, Spey-Phantom & TSR.2 is required.

 

[NOMISYRRUC]

Anything short of 1000nmi might as well stay as a technology demonstrator.

That may be ALT-Black Knight ITTL. That is it used solid fuel instead of hydrogen peroxide/kerosene.

 

[Dilandu]

I'm going to assume that the UK had sufficiently good engineers as to make "miniature" sized nukes by 1963 or so.

Oh, quite possibly. One problem; in 1955 they COULD NOT BE SURE they would be able to do it by 1963. Even for Americans - which lead the world in nukes at this time - it was a gamble. And considering how bad was early Polaris warheads, they almost lose. Britain could not afford such gamble; it neither have technological confidence, nor resources to fall back.

Jupiter is 18.3m/60ft long and 2.67m/8'9" in diameter, weighs a good 50mt/110klbs. It's carrying a W49 warhead that weighs 740kg/1640lbs and has a yield of 1.44MT. Range kinda sucks with that heavy warhead, only ~2500km.

The problem is, Jupiter was made by engineers, who already have many prior experience with designing ballistic missiles - Corporal, Redstone, numerous test vechicles. Which wouldn't be the case for Britain.