Royal Navy Type 82 Alternatives and comparisons with other navies

[uk 75]

Other threads have thrown up an issue which interests me greatly: What sort of ship should the Royal Navy have built to follow up and eventually replace the County Class missile destroyers?

The candidate originally chosen, the Type 82 proved less than successful. It was considered under armed and had difficulty with its propulsion systems.

The Dutch Navy built a two vessel class, the Tromp, which served it well until the end of the Cold War. The Germans and the Australians built their own versions of the US Charles Adams class, again these ships served until the end of the Cold War in 1991. Italy went its own way and built the Ardito class which drew on experience with the earlier Impavidos. Japan started with the single ship Amatzukaze and gradually built ships in small batches.

What do you think?

 

[JFC Fuller]

Any Sea Dart ship with Sea Cat/Sea Wolf, a short range capability was the one thing missing from both the T82 and T42 designs. I am not aware of any particular complaints about the Type 82 beyond the fact that it was too expensive to order in the numbers originally required. It offered more missiles, better missiles and more channels of fire compared to the County class in its main AAW armament. I know there was the four hour fire that destroyed the steam plant and injured four crew during sea trials in 1974 but I was not aware that this was any particular design issue with the propulsion aside from the similar dissatisfactions with the County class plant compared to a full GT plant?

 

[Hobbes]

The Tromp class had problems of its own, mainly structural issues with the aluminium superstructure on top of a steel hull. IIRC a British weapons fit was considered for the Tromp class (in exchange for the Broomstick radar being fitted to British vessels). I haven't found much detail on this plan, but given how Tromp turned out, the RNLN would have tried to fit Sea Dart plus Sea Wolf.

 

[Tony Williams]

IIRC a British weapons fit was considered for the Tromp class (in exchange for the Broomstick radar being fitted to British vessels).

Oh very funny - not exactly calculated to please the RN!

(from Wiki: "There is also a story that, after his victory at Dungeness, Tromp attached a broom to his mast as a symbol that he had swept the English from the sea.") ;D

 

[Abraham Gubler]

Other threads have thrown up an issue which interests me greatly: What sort of ship should the Royal Navy have built to follow up and eventually replace the County Class missile destroyers?

The big problem with this question is the actual DDG planed (the Type 82) was conceived as part of a carrier battle group in which four escorts (Type 82s) would accommodate a strike carrier (CVA-01) and an escort carrier/cruiser. So things which we may now consider to be shortfalls on a Type 82 like the lack of helicopter capability were not so important because these systems were to be concentrated more efficiently on the battle group carriers.

The candidate originally chosen, the Type 82 proved less than successful. It was considered under armed and had difficulty with its propulsion systems.

I don’t know where you get this from. The Type 82 was actually a great success of a design. It was the only RN ship of its generation not to have structural problems. There were no problems with its propulsion system except for a boiler fire which was a non-design issue. As for being under armed it carried over 60 guided missiles or one missile per 100 tonnes which was about twice as good as the Type 42 Batch 1 which followed it and one and a half times better than the County which preceded it.

The Dutch Navy built a two vessel class, the Tromp, which served it well until the end of the Cold War.

The Tromp class was built well after the Type 82 and is no contemporary of it. It used the Tyne/Olympus engine room which was under development at the time the Type 82 was built.

The Germans and the Australians built their own versions of the US Charles Adams class, again these ships served until the end of the Cold War in 1991.

They actually served longer than that. But like the Tromps they were a different generation than the Type 82s in this case the previous one. As built with Tartar they were quite inferior to the Type 82 for anti-aircraft capability.

What do you think?

I don’t think you’ve made any sort of argument here. In the start of the 1960s the UK was still a prime developer of combat systems but by the end they weren’t. I find it hard to see how they wouldn’t launch CF.299 (Sea Dart) in the early 60s considering the problems of Sea Slug and their requirement for a new escort for the CVA-01. The key thing about the ships of other nations you mention is they were all built for Tartar which was a less capable but more compact system than Sea Dart. Sea Dart was en par with Terrier and really any comparison should be on this baseline. With USN DLGs, French Sufferen and Italian Andrea Doria types.

IIRC a British weapons fit was considered for the Tromp class (in exchange for the Broomstick radar being fitted to British vessels).

Oh very funny - not exactly calculated to please the RN!

(from Wiki: "There is also a story that, after his victory at Dungeness, Tromp attached a broom to his mast as a symbol that he had swept the English from the sea.")

Broomstick was known in the RN as Type 988 or CDS (Comprehensive Display System) and was a joint project with the Dutch. D.K. Brown quipped that whoever approved the name “Broomstick” from the British side “did not know his history”. After the RN pulled out the Dutch built two called SPS-01 and they sat around for almost half a decade before they were installed on the Tromp class.

 

[JFC Fuller]

Broomstick was known in the RN as Type 988 or CDS (Comprehensive Display System)

Actually the Comprehensive Display System (CDS) was an analogue combat management system produced by Elliot Brothers and usually associated with the earlier Type 984 3D radar though it was also used with other radars. It was installed on the first four County class destroyers, HMS Victorious and HMS Hermes. It was also approved for HMS Tiger, HMS Lion and HMS Blake though I have not been able to confirm if it was installed in those ships. One system was also dispatched to the US. The systems associated with the Type 988 were ADAWS-2 (Type 82) and ADAWS-3 (CVA-01). ADAWS was essentially the digital ADA (Action Data Automation), as installed in HMS Eagle, with added weapons control functionality (Weapons System, thus ADAWS) and was first installed in the Batch 2 County class ships. ADAWS-4 was for the Type 42 class, ADAWS-5 for Ikara Leander, ADAWS-6 for the Invincible class, and then further variants and modifications through to ADAWS-12 which was a late upgrade to the Type 42 system. There is some confusion because some sources have referred to ADAWS as a comprehensive display system but in reality that name was for the earlier Elliot's analogue system and Type 988 was never known as that.

It was the only RN ship of its generation not to have structural problems.

I assume you are referring to the Type 21 and the Type 42 batch III?; the other RN ships of the time had no such troubles that I can recall (though if I have missed some please do remind me), the Fearless class were fine, all the fleet support ships were fine, the Leanders were fine, the Type 22s were fine and whilst cramped the first two batches of the Type 42 class were fine. Either way, I would argue that the Type 82 is a generation alone, a hybrid between the 50s ships and the late 60s/early 70s ships. She was derived directly from the Leander class whilst her machinery was essentially a County class COSAG plant but with the Metrovick G6 gas turbines replaced by the later Olympus and she carried the RN arsenal of the 70s.

The Tromp class was built well after the Type 82 and is no contemporary of it. It used the Tyne/Olympus engine room which was under development at the time the Type 82 was built.

As I said above I regard Bristol as something of a generational hybrid but equally I think it is reasonable for anyone to regard her as a rough contemporary of Tromp. That ship was laid down only 33 months after HMS Bristol and commissioned only 30 months later than Bristol. It is also interesting to note that as early as 1963 a combined Proteus-Olympus plant was being rejected as unlikely to be ready in time for the high-end frigates then under consideration and an all gas-turbine plant was rejected as premature in the same year for the Type 82. With the benefit of hindsight Bristol probably could have been built on a very similar if maybe slightly later timetable with a full GT plant. The marine Olympus (as used in Bristol) first underwent shore trials in 1966 and the marine Tyne in 1967, the Proteus was available much earlier having been used in the Brave class fast attack craft from 1960. Furthermore a pair of Proteus were put in a COGAG plant with a single derated Olympus running through a David Brown gearbox (AEI had done the gearbox for the County Class and Bristol but David Brown got the Type 42 & 21) for Sea Trials in HMS Exmouth in 1968, the year after Bristol was laid down.

 

[Abraham Gubler]

Actually the Comprehensive Display System (CDS) was an analogue combat management system produced by Elliot Brothers and usually associated with the earlier Type 984 3D radar though it was also used with other radars.

In both CVA-01 and Type 82 CDS was referred to as including the Type 988 radar which would provide it with the all-important radar measurements (system was not much use without them) when it was being conceived for order. So when someone said CDS in 1965 this is what they meant. Getting upset with this is like making the point that AEGIS is technically not the SPY-1 radar array but the combat system that runs it.

I assume you are referring to the Type 21 and the Type 42 batch III?; the other RN ships of the time had no such troubles that I can recall (though if I have missed some please do remind me), the Fearless class were fine, all the fleet support ships were fine, the Leanders were fine, the Type 22s were fine and whilst cramped the first two batches of the Type 42 class were fine.

Fearless was not a surface combatant, Leander and Type 22 were not designed in the second half of the 1960s (Types 21, 42 and 82 were). Anyone with half a brain and a teaspoon of common sense would realise I was referring to frigate/destroyers and from a certain timeframe. As to the Batch 1 type 42 structurally it may have been fine but it was a dog of a sea boat. The type 82 wasn’t. A vessel with significant compromises in its hull form is not what I would consider sound. This splitting of hairs nonsense is not appropriate conduct in what is just a discussion forum. You understand what I meant as did everyone else. Now get over it.

That ship was laid down only 33 months after HMS Bristol and commissioned only 30 months later than Bristol.

33 months is still 2 1/2 years. You could say exactly the same thing with Tromp removed and replaced by Type 42. So why did the RN build the Type 82 rather than the Type 42? Because when the Bristol was ordered and laid down one couldn’t build a Type 42 just as one couldn’t built a Tromp because the propulsion system was not fully designed! This is a nonsense argument. In fact Sealordlawrence's (aka JFC Fuller) entire last post seems to be an attempt to get 'one over' me rather than any kind of reasoned input to discussion. Its more troll than anything else.

 

[JFC Fuller]

In both CVA-01 and Type 82 CDS was referred to as including the Type 988 radar which would provide it with the all-important radar measurements (system was not much use without them) when it was being conceived for order. So when someone said CDS in 1965 this is what they meant.

It is actually a very important distinction, CDS was much earlier, from a different manufacturer and used analogue rather than digital. CDS was not associated with the Type 988, ADAWS was. Indeed very few sources talk about "a" CDS versus the actual CDS. It is a far more significant generational difference than that between the Type 82 and Tromp.

Fearless was not a surface combatant, Leander and Type 22 were not designed in the second half of the 1960s (Types 21, 42 and 82 were). Anyone with half a brain and a teaspoon of common sense would realise I was referring to frigate/destroyers and from a certain timeframe. As to the Batch 1 type 42 structurally it may have been fine but it was a dog of a sea boat. The type 82 wasn’t. A vessel with significant compromises in its hull form is not what I would consider sound.

My apologies, you only said ships, not surface combatants. It was only the batch III Type 42s that suffered structural problems and they were not designed until the mid-70s so certainly not from the second half of the 60s. The Batch I ships were not ideal sea boats that is true but they did not have structural problems to my knowledge and that was what you were referring too.

33 months is still 2 1/2 years. You could say exactly the same thing with Tromp removed and replaced by Type 42. So why did the RN build the Type 82 rather than the Type 42? Because when the Bristol was ordered and laid down one couldn’t build a Type 42 just as one couldn’t built a Tromp because the propulsion system was not fully designed!

Yes you could, because all three are more-or-less from the same generation. I absolutely agree with UK75 on this. In naval construction terms 2 and a half years is not much time at all. The first Type 42 was ordered before Bristol was even launched. Indeed much of what I was trying to convey in my previous post was that the Type 42 probably could have been ordered earlier if had been designed earlier, it wasn't designed because the RN thought it was getting carriers, as you pointed out earlier, but all the core systems required for it- gas turbines, armament, sensors and CMS, were all in existence.

 

[Abraham Gubler]

Only until ADAWS was confirmed,

So you agree, great. I was right and you’ve been wasting everyone’s time with hair splitting.

My apologies, you only said ships, not surface combatants.

Perhaps you should also include merchant ships, life boats, hovercraft, etc into you troll attempt? Considering I mentioned “generation” how is it that a creature from another species, like a landing ship or auxiliary, can be considered part of the same “generation”?

the Type 42 probably could have been ordered earlier if had been designed earlier

LOL. Why stop there? Couldn’t the RN have ordered the Queen Elizabeth class battleship in place of the Dreadnaught? Spitfires in 1918? All they had to do was design them earlier…

but all the core systems required for it- gas turbines, armament, sensors and CMS, were all in existence.

Actually this is very not true. While the Olympus and Tyne turbines may have existed before 1967 the COGOG engine room didn’t. This was under development until it was ready cruise on Gas Turbine and the space savings compared to steam or diesel was not a feasible idea. In the overall build history of many ships 2.5 years may not seem like much but it’s a chasm when it happens to appear before a key item of technology is available.

 

[JFC Fuller]

So you agree, great. I was right and you’ve been wasting everyone’s time with hair splitting.

As I said, they are completely different systems, different manufacturers, different technology and CDS was not associated with Type 988.

Perhaps you should also include merchant ships, life boats, hovercraft, etc Considering I mentioned “generation” how is it that a creature from another species, like a landing ship or auxiliary, can be considered part of the same “generation”?

You said only said RN ships, thus I assumed you meant all RN ships, I apologise for misunderstanding you. As far as I am aware the only RN ship class designed in the late 1960s that experienced structural problems was the Type 21 class. The Type 42 Batch III not being designed until the mid 1970s and the Type 42 Batch I/II ships did not experience structural problems.

LOL. Why stop there? Couldn’t the RN have ordered the Queen Elizabeth class battleship in place of the Dreadnaught? Spitfires in 1918? All they had to do was design them earlier…

There were no Merlin engines in existence in 1918 and no RN 15" guns when Dreadnought was built. There were Sea Dart systems, ADAWS, Olympus, Tyne, Proteus etc when the Type 82 was built.

Actually this is very not true. While the Olympus and Tyne turbines may have existed before 1967 the COGOG engine room didn’t. This was under development until it was ready cruise on Gas Turbine and the space savings compared to steam or diesel was not a feasible idea. In the overall build history of many ships 2.5 years may not seem like much but it’s a chasm when it happens to appear before a key item of technology is available.

Actually it is very true. There is nothing special about the COGOG engine room. It is just the chosen gas turbines rated to the desired outputs and running through an appropriate set of gearing with provision for the required fuel lines, air uptakes and exhausts. Conceptually it is no different from a steam turbine room. The weight and space savings come from gas turbines being very light and them not requiring boilers- thus removing a stage from the propulsion process. A split cruise and boost configuration was nothing new either having even been used on the Invincible class battlecruisers and Neptune class battleships in steam form. It is just a case of having the desired gearing and turbine outputs. All the technology existed to do this when HMS Bristol was built, that is why the decision was taken to convert HMS Exmouth to a COGOG configuration in 1966, the year before Bristol was laid down, and why Exmouth was at sea in that configuration in 1968- the year before Bristol was launched.

 

[Abraham Gubler]

All the technology existed to do this when HMS Bristol was built, that is why the decision was taken to convert HMS Exmouth to a COGOG configuration in 1966, the year before Bristol was laid down, and why Exmouth was at sea in that configuration in 1968- the year before Bristol was launched.

So what you are saying is you have no problems with the design of the Type 82. You have a problem with the ability of the RN to identify gas turbines as appropriate motors for their fleet. One could ask why didn’t the Royal Navy identify the 15” gun in 1905 as the future of battleships? Or why didn’t Sopwith realise in 1916 they could build semi-monocoque cantilever monoplanes out of aluminium powered by V12 motors? It’s all the same thing. You want to go back in time and hurry up the course of history. That’s not alternate history; its science fiction.

 

[Hobbes]

They actually served longer than that. But like the Tromps they were a different generation than the Type 82s in this case the previous one. As built with Tartar they were quite inferior to the Type 82 for anti-aircraft capability.

Could you expand on this? What made them inferior? The missiles themselves? Combat system? Sensors?

 

[JFC Fuller]

So what you are saying is you have no problems with the design of the Type 82. You have a problem with the ability of the RN to identify gas turbines as appropriate motors for their fleet. One could ask why didn’t the Royal Navy identify the 15” gun in 1905 as the future of battleships? Or why didn’t Sopwith realise in 1916 they could build semi-monocoque cantilever monoplanes out of aluminium powered by V12 motors? It’s all the same thing. You want to go back in time and hurry up the course of history. That’s not alternate history; its science fiction.

I have no problem with RN propulsion choices in the period, they propelled the ships they needed to. All I am suggesting is that given the RN considered an all GT plant for the Type 82 in 1963, decided to convert a frigate to an all GT plant a year before ordering Bristol and had that all GT frigate at sea the year before Bristol was launched it is entirely reasonable to suggest that Bristol could have been built with an all GT plant. There were no RN 15" guns in 1905 and "semi-monocoque cantilever monoplanes out of aluminium powered by V12 motors" were beyond state of the art in 1916, by contrast, in 1968-before Bristol was even launched, the RN had an all gas turbine ship at sea having previously built two ship classes with COSAG plants and two classes of all GT powered fast attack craft. With that in mind it does not seem to be science fiction to suggest that Bristol could have been built with an all GT plant.

 

[Abraham Gubler]

Could you expand on this? What made them inferior? The missiles themselves? Combat system? Sensors?

Tartar was a much shorter range missile than Sea Dart. Tartar went through continuous improvement and with Digital Tartar (Block III) was renamed Standard SM-1MR. Tartar at its best had a max range of 17.5 NM, Standard SM-1MR 25 NM whilst Sea Dart had a range of 40 NM. Sea Dart Mod 1 with the autopilot has a maximum range of 80 NM despite weighing in at 1,200 lbs. SM-2ER with autopilot has a maximum range of 100 NM but weighs in at just under 3,000 lbs. 2.5 times the missile for 1.25 times the range.

 

[Tony Williams]

Tartar was a much shorter range missile than Sea Dart. Tartar went through continuous improvement and with Digital Tartar (Block III) was renamed Standard SM-1MR. Tartar at its best had a max range of 17.5 NM, Standard SM-1MR 25 NM whilst Sea Dart had a range of 40 NM. Sea Dart Mod 1 with the autopilot has a maximum range of 80 NM despite weighing in at 1,200 lbs. SM-2ER with autopilot has a maximum range of 100 NM but weighs in at just under 3,000 lbs. 2.5 times the missile for 1.25 times the range.

A consequence of the greater efficiency of an air-breathing ramjet over a solid-fuelled rocket which has to carry its oxidiser with it.

It does seem curious that when ramjets are being adopted elsewhere when long range and high speed are required (e.g. in the new Meteor AAM) the RN should be changing from a ramjet missile to a solid fuelled one.

I suppose that for the very high-altitude anti-ballistic-missile role, a ramjet may run out of enough air to function well, but I'm not sure at which altitudes this becomes an issue.

 

[uk 75]

Much interesting material from everyone for which I am very grateful. I will try and answer some points relating to my initial posting.

Comparison with other Western ships I used ships that were ordered or being designed in the 1961 to 1966 timeframe. The closest analogues in timeline seem to be the Italian Arditos which were designed and introduced into service in the same period as Bristol. However, my broad point was to show the reliance of everyone else on Tartar (not Terrier, this was only used on Vittorio Veneto) and also the apparently heavier armament on some of the other ships

Armament I was drawing on comments in a variety of 70s magazines comparing the Type 82 unfavourably with other designs in that it had only one main gun, no point defence missile system, no space available for fitting surface to surface missiles, and only one Seadart launcher on such a large ship

Propulsion Again I have not got the magazine article to hand but it was from about the mid 80s and made the point that the steam boilers in Bristol gave constant trouble and the ship usualy relied on its gas turbines. I have not checked this or compared it with the County class record, so I accept it may be wrong

Alternative path of development Superficially it seems that the RN could have introduced 8 Type 82s into service by 1980 instead of 8 Type 42s and converting 8 elderly Leanders to Ikara platforms. The Type 82s might have been able to trade their ASW weapons for a Seawolf fit, making them pure Air Defence ships. I admit that I rather hanker after a pure anti aircraft ship from the off, with Seadart forward instead of Ikara forward and Seacat 2s aft. Again these thoughts are probably moonshine!

I would offer one observation on the tone of some comments. This site is supposed to allow a free exchange of ideas and info. We all have different specialisms and skill levels, as well as access ot different material. If anyone is deliberately just trying to score points I just assume that they are not and accept their contribution for whatever interesting info or views it contains.

 

[JFC Fuller]

Armament I was drawing on comments in a variety of 70s magazines comparing the Type 82 unfavourably with other designs in that it had only one main gun, no point defence missile system, no space available for fitting surface to surface missiles, and only one Seadart launcher on such a large ship

Do you recall which magazines? I would be curious to read them. It is worth noting that Bristol also carried Limbo and at least two systems she was intended to take were never installed, the Type 988 and a Type 199 VDS so there was an element of unused space and weight.

Propulsion Again I have not got the magazine article to hand but it was from about the mid 80s and made the point that the steam boilers in Bristol gave constant trouble and the ship usualy relied on its gas turbines. I have not checked this or compared it with the County class record, so I accept it may be wrong

It is certainly possible but I suspect those articles are referring to the fact that there was two years between the boiler room fire and the steam plant being repaired during which the ship did rely on its GT plant. Apparently so much water was pumped into the ship to extinguish the fire that there was concern she may capsize.*

Alternative path of development Superficially it seems that the RN could have introduced 8 Type 82s into service by 1980 instead of 8 Type 42s and converting 8 elderly Leanders to Ikara platforms. The Type 82s might have been able to trade their ASW weapons for a Seawolf fit, making them pure Air Defence ships. I admit that I rather hanker after a pure anti aircraft ship from the off, with Seadart forward instead of Ikara forward and Seacat 2s aft. Again these thoughts are probably moonshine!

The earliest plan was for what became the Type 82 to be a follow on to the Leander class but it was just too expensive; Friedman goes into the analysis the RN did in some depth. You probably would not have to sacrifice Ikara for Seacat. I must admit that I have always found it something of an oddity that a Seacat installation was not considered for the Type 82 given that the system was fitted to the County class.

* http://www.independent.co.uk/news/people/obituary-rearadmiral-sir-hugh-janion-1378144.html

 

[uk 75]

I must own up to a problem with my source material. Back in the 80s and 90s I was able to get hold of copies of a range of magazines including

International Defense Review/Interavia
Jane's Defence Weekly
Aviation and Marine/Armies and Weapons (Italian/Swiss)
Ian Allen's Armed Forces/Battle

as well as Navy International, Flight International, Air Pictorial and some Aviation Week and Space Technologies.

Unfortunately as I was always moving around on jobs I tended to cut out the stuff I thought was interesting and either put it in the relevant book (my library was much smaller in those days) or boxed American wargame (very much a 70s/80s thing). A lot of cuttings ended up in folders and got muddled up. I also used to photocopy particularly interesting pages from library copies.

The upshot is I tend to remember quite a lot of this material, having looked at it often, but cannot find the piece of paper in question. Hence my sometimes odd contributions.

Turning to my points

Underarmament The main culprit for this debate was Aviation and Marine which always
seemed to compare Royal Navy ships unfavourably with foreign ships.
International Defense Review and Janes were sometimes also harsh.

Propulsion The boiler saga I think was in article from a Sunday colour sup and
also in an Ian Allen mag. I think JFC is probably on the button and
I misremembered.

On the development point I think my fondness for the Type 82 is purely a matter of size, I was always dismayed that the RN was forced to build such small hulls. In contrast the US Navy built ships with plenty of room for upgrading armament (although even they were constrained in some cases). A Type 82 Air Defence ship with Seadarts forwrd and aft and space for Seacat/Seawolf seems to me more useful than the General Purpose version since other ships in a Task Group could provide gunnery and ASW, as happened with the Type 21s and Type 22s. 8 such vessels could have been built for the cost of the Type 42s built and been in service earlier.

The Leanders seem in fact to have been a good way of getting Ikaras into a task group. The rather odd British variant was due to needing nuclear capability, which then never materialised.
I think I am right in saying that some thought nuclear depth bombs were the only certain way of killing advanced Soviet subs (though it would have screwed up the tracking of any more afterwards).

The Type 42 is consistent with the original requirement for a frigate sized ship to carry Seadart and started life much less capable than the variant that entered service, with only one director and a different launcher. The US Navy's Perry class seem a good analogue with their limited armament. I think somewhere else in the threads there is discussion of whether Perrys were better value than 42s.

 

[Abraham Gubler]

It does seem curious that when ramjets are being adopted elsewhere when long range and high speed are required (e.g. in the new Meteor AAM) the RN should be changing from a ramjet missile to a solid fuelled one.

I don’t think there was any thinking in regard to this change from ramjet to solid. It was simply a matter of SM-2 or Aster being the only off the shelf options available.

I suppose that for the very high-altitude anti-ballistic-missile role, a ramjet may run out of enough air to function well, but I'm not sure at which altitudes this becomes an issue.

Most missiles are coasting at the end of their range performance anyway and the notional ramjet would probably have run out of kerosene well before 80,000 odd feet robs it of air for the motor as well.

 

[Tony Williams]

Most missiles are coasting at the end of their range performance anyway and the notional ramjet would probably have run out of kerosene well before 80,000 odd feet robs it of air for the motor as well.

Depends on the slant range. 80,000 feet is only 15 miles up and, as you pointed out yourself, Sea Dart's maximum range is several times that.

 

[Abraham Gubler]

Depends on the slant range. 80,000 feet is only 15 miles up and, as you pointed out yourself, Sea Dart's maximum range is several times that.

I don’t know the specifics of the Sea Dart’s full performance envelope but while 15 miles up is shorter than 40 miles across the two are not equal because more gravity to fight in one direction and no advantage of aerodynamic lift from the wings. I did upload to this forum a sales brochure for Bloodhound 2 which should show some of the performance differences in altitude versus range.

 

[pathology_doc]

And all this presupposes that an air-breathing missile is even capable of performing an ABM kill high enough to prevent a salvage detonation from EMP-scrubbing the task force's systems and letting the second (hardened) warhead through. Whether a more modern iteration with updated microelectronics (especially for engine and trajectory management) and more space for better fuel could do it is of course another matter, but the tendency for ABM-capable missiles to have an air-independent propulsion system is quite understandable, especially if you want to extend your reach to low-orbit satellites.