Can a County be enlarged on the same power-plant and retain the same speed and range?

The RN settled on the 53,000t CVA01 because to go to the 58,000t would have required a 4 shaft power-plant that would have cost 30% more but not provided commensurate tactical value.

So does the same apply to an enlarged County, that it would require a more powerful power-plant at higher cost but without a commensurate increase in tactical value?
 
Friedman goes into some detail in his books on British warships about the numbers deemed necessary for various tasks.
A clear thread running through all his accounts is the policy of using the cheapest ship with the smallest crew.
Pennywise Poundfoolish is the inevitable outcome of such an approach.
If it had been possible to use a Type 12 to carry CF299/Seadart the RN would have done it. As it was the T42 was kept too small until the four batch 3s.
The Tigers were initially the cheapest, smallest ships the RN could deploy as Swerdlow killers. From 1962 they were the cheapest smallest ships to command a task group and deploy ASW helos (as well as being the most powerful surrface to surface ships after aircraft carriers).
The excellent Shipbucket has pages devoted to "fantasy" as well as "proposed but never built ships" If I could draw my take would be a British Albany with Nigs fore and Aft. CF299 in side mountings
 
Pennywise and Pound Foolish is only the inevitable outcome if that logic is taken too far.



It’s important to bear in mind that in the late 50s and well into the 60s planned to (and did in several cases) order very large numbers of ships; 20 Type 81 frigates, 10 County class DLGs and 5 CVAs.



I don’t know at what point in time it was made, but IIUC ¼ of a ship’s cost was the structure, ¼ is the power-plant and the rest is armament etc. A ~15 million pound County class structure cost ~3.75 million pounds, making it 10% larger costs ~375,000, multiplied by 10 ships it pays for the structure of an 11th County or most of a 4.3m pound Leander. What’s more an increase in size by 10% will result in a loss of speed and range unless perhaps the Counties use a 40,000hp Cruiser rather than 30,000hp Destroyer power-plant, which further drives up costs for the 10 DLGs.



I’m sure everyone is going to quibble with my figures, good because they’re a guess based on a vague memory, but a Tiger or County is not the same as a Type 42 where shrinkage directly impeded combat capability by making the primary armament magazine too small.
 
A selection of quotes from Posts 161 and 162.
Friedman goes into some detail in his books on British warships about the numbers deemed necessary for various tasks.
A clear thread running through all his accounts is the policy of using the cheapest ship with the smallest crew.
The RN needed large numbers of ships from the Age of Sail to at least the end of the Cold War. Therefore, they had to find the sweet spot between being cheap enough to be built in the numbers required and fitness for purpose.
Pennywise Poundfoolish is the inevitable outcome of such an approach.
Pennywise and Pound Foolish is only the inevitable outcome if that logic is taken too far.
"Look after the pennies and the pounds will look after themselves". Anon.

"Annual income twenty pounds, annual expenditure nineteen and six, result happiness. Annual income twenty pounds, annual expenditure twenty-pound ought and six, result misery". Mister Micawber.

From https://history-commons.net/artifacts/2615603/the-fourth-arm-of-defence/3638192/ which is dated 1st January 1939.
THE FOURTH ARM OF DEFENCE

THIS war will be won by the power of our money as well as by the valour of our men. To save and lend is the duty of the citizen. "Finance is the fourth arm of defence," says the Chancellor of the Exchequer, "no less important than the other three, and if finance fails then the whole of the prop that sustains our war effort will collapse."
In common with Donald Pleasence as Septimus Harding in the 1982 adaptation of “The Barchester Chronicles” I can see both sides of the argument.

We know when they got it wrong. But in their defence do we know how many times they got it right?
If it had been possible to use a Type 12 to carry CF299/Seadart the RN would have done it.
Certainly, because if I remember correctly, what became Type 82 began as a Leander size vessel.
As it was the T42 was kept too small until the four batch 3s.
. . . as a Type 42 where shrinkage directly impeded combat capability by making the primary armament magazine too small.
While I agree that Type 42 Batches 1 & 2 were too small I doubt that having another 16 Sea Darts in their magazines would have saved Sheffield & Coventry. Plus there have been discussions [heated debates][arguments] on this forum about whether the Type 42 Batch 3 ships had larger Sea Dart magazines in the first place.

On the other hand are there examples of other ships being sunk or damaged because the Type 42s were running out of Sea Dart missiles? The only example I can think of was Exeter running low on Sea Darts during the action that allegedly resulted in Invincible being hit (which I don't believe) but in the account of that action that I read she was sent to the Falklands without a full magazine of Sea Darts anyway.

I think the major defect of the early Type 42s was the Type 965 radar and that only applied to the Batch 1s because the (short-hull) Batch 2s were the first ships to be completed with the Type 1022.

On the other hand a larger hull might have allowed greater internal subdivision and increased buoyancy so they might have taken longer to sink. I think Brown wrote that the Type 42s were designed to stay afloat if two watertight compartments were flooded and that Coventry was hit in four so she stood no chance. Would the larger hull have saved her? Unfortunately, I think not.
 
Why not enlarge the County from circa 5,400 tons to about 6,000 tons so it could accommodate a Type 984? That would have the advantage of a bigger magazine for the Seaslugs, maybe a second Type 901, a more powerful CDS & better arrangements for the helicopter. Yes it would require more powerful machinery, yes it would require a bigger crew and yes it would be more expensive to build & to run. But the increase in capability would more than justify the increase in cost.

Edit: 14.11.24

The displacement of 5,400 tons is according to Leo Marriott in "Royal Navy Destroyers Since 1945", which on Page 110 says that their standard displacement was 5,440 tons and the full load displacement was 6,200 tons.

Other reference books say differently. E.g. Conway's 1947-1995 says 6,200 tons normal displacement and 6,800 tons full load.
When it comes to the County class being enlarged, they were still gun and steam ships despite their GTs, missiles and electronics. There were initially 10 planned and 4 laid down in the first year of construction. My guess is if they were enlarged from the get-go to accommodate both guns and the Type 984 the increase in cost would mean limiting the planned numbers to something like 7 or 8 instead of 10, which is likely insufficient to undertake the RNs allocated tasks.
I was contributing to the discussion on how to get a Type 984 onto a County class destroyer and your reply takes us back to the dilemma of numbers of ships v the capability of each ship.

For what it's worth I think a second Type 901 is better than a Type 984 for the County class as doubles the number of targets it's Seaslug could engage. As the helicopter facilities weren't exactly satisfactory could they have been replaced by a second Type 901 without having to enlarge the hull and the problems that would create with the building and operating costs?

However, we do need a better radar than the Type 965 PDQ. Fortunately, @Hood and @zen have written in this thread (I think because I haven't checked) and elsewhere about how we could have got an equivalent to SPS-48 and/or Type 1022 sooner.
 
Vital statistics of the Tiger class, County class and the American DLGs
(Data from Conway's 1947-1995)

Dimensions of Tiger class, County class DLG and American DLGs.png

The book says light load and deep load for Tiger. It also says that Tiger's crew was 880, but that was the crew after her conversion to a helicopter cruiser. According to the book her Helicopter Cruiser conversion increased the displacements to 9,975 tons standard and 12,080 deep load.

I think the dimensions are what is illuminating.
  • I didn't expect the Tiger class to be only 33ft (pp) longer than the County class and the difference in beam is less than I expected too. My guess is that the Tigers were a weight critical design and the Countys were volume critical.
  • Furthermore, I expected the American DLGs to be longer and beamier than the Countys. Whereas the County, Farragut & Leahy classes are roughly the same length, only the Belknap class is significantly longer than a County and all four classes have about the same beam.
  • The Belknap class wasn't much shorter than the Tiger class.
I was also surprised that the American ships had significantly smaller crews than the County class.
 
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On the other hand are there examples of other ships being sunk or damaged because the Type 42s were running out of Sea Dart missiles? The only example I can think of was Exeter running low on Sea Darts during the action that allegedly resulted in Invincible being hit (which I don't believe) but in the account of that action that I read she was sent to the Falklands without a full magazine of Sea Darts anyway.

The Type 42 was designed to fight WW3 with the Soviet Union's AVMF against dozens of bombers firing dozens to hundred of big AShMs. Standard practice was to fire 2 Sea Darts at each target, a practice that I think was followed in the Falklands, IIUC Invincible fired 6 Sea Darts during the engagement where it was claimed she was sunk and Exeter fired 2 at the Learjet she shot down. I'd think that in WW3, even if some economy was realised (maybe 3 missiles for 2 closely spaced targets) these ships could engage 11-15 targets rather than 20-27 with a 40 round magazine.
 
The Type 42 was designed to fight WW3 with the Soviet Union's AVMF against dozens of bombers firing dozens to hundred of big AShMs. Standard practice was to fire 2 Sea Darts at each target, a practice that I think was followed in the Falklands, IIUC Invincible fired 6 Sea Darts during the engagement where it was claimed she was sunk and Exeter fired 2 at the Learjet she shot down. I'd think that in WW3, even if some economy was realised (maybe 3 missiles for 2 closely spaced targets) these ships could engage 11-15 targets rather than 20-27 with a 40 round magazine.
I'm somewhat nonplussed by the above.

FWIW & IIRC Exeter fired 2 Sea Darts in that action because she was conserving her ammunition due to sailing for Falklands with less than her capacity of 24 Sea Darts. Which is a pity because the extra missiles would have been useful as she and Invincible* were the only ships with the Type 1022 radar and shot down more aircraft per missile fired than the Type 42s with the Type 965 radar. I have remembered correctly (and I'm not sure that I do) it's even more the pity that she that she wasn't built with a Batch 3 hull and was sent to the Falklands with with 40 Sea Darts instead of around 15.

* Maybe Invincible fired 6 because her capacity was IIIRC 40 Sea Darts and AFAIK she went to the Falklands with her Sea Dart magazine full so her captain didn't have to worry about running out of missiles.
 
Can a County be enlarged on the same power-plant and retain the same speed and range?

The RN settled on the 53,000t CVA01 because to go to the 58,000t would have required a 4 shaft power-plant that would have cost 30% more but not provided commensurate tactical value.

So does the same apply to an enlarged County, that it would require a more powerful power-plant at higher cost but without a commensurate increase in tactical value?
I simply don't know and suspect that it depends upon how large the enlargement is.

But, the broad-beamed Leanders had the same machinery as the standard Leanders. Yet as far as I know they weren't slower and didn't run out of fuel sooner.

And the Type 42 Batch 3 was 42ft (wl) longer and 2ft beamier than its predecessors and had the same machinery* as its predecessors. Yet as far as I know they weren't slower and didn't run out of fuel sooner.

However, the larger hulls of the broad-beam Leander and Type 42 Batch 3 probably allowed more fuel to be carried so that might have been why they didn't run out of fuel sooner than their predecessors.

*Data is from "Modern Combat Ships 3, Type 42" by Leo Marriott. According to him all 3 batches had 2 Olympus TM3B, each producing 25,000shp, Batches 1 & 2 had 2 Tyne RM1A producing 4,250shp and Batch 3 had 2 Tyne RM1C which also produced 4,250shp.
 
A clear thread running through all his accounts is the policy of using the cheapest ship with the smallest crew.
ISTR the RN/UK was facing a manpower crisis throughout the 50s, and manpower is a major through-life cost, so minimum crew was an important design goal.
 
Which is hardly surprising, among the major allies GB wwas the one and only "medium power" to bore the brunt of both wold wars. USA and USSR were far larger and populated, France took tremendous losses in WWI but seating out of most of WWII inflicted lower losses. Among european countries perhaps only Germany had more losses.
 
The Type 42 was designed to fight WW3 with the Soviet Union's AVMF against dozens of bombers firing dozens to hundred of big AShMs. Standard practice was to fire 2 Sea Darts at each target, a practice that I think was followed in the Falklands, IIUC Invincible fired 6 Sea Darts during the engagement where it was claimed she was sunk and Exeter fired 2 at the Learjet she shot down. I'd think that in WW3, even if some economy was realised (maybe 3 missiles for 2 closely spaced targets) these ships could engage 11-15 targets rather than 20-27 with a 40 round magazine.

I'm somewhat nonplussed by the above.

FWIW & IIRC Exeter fired 2 Sea Darts in that action because she was conserving her ammunition due to sailing for Falklands with less than her capacity of 24 Sea Darts. Which is a pity because the extra missiles would have been useful as she and Invincible* were the only ships with the Type 1022 radar and shot down more aircraft per missile fired than the Type 42s with the Type 965 radar. I have remembered correctly (and I'm not sure that I do) it's even more the pity that she that she wasn't built with a Batch 3 hull and was sent to the Falklands with with 40 Sea Darts instead of around 15.

* Maybe Invincible fired 6 because her capacity was IIIRC 40 Sea Darts and AFAIK she went to the Falklands with her Sea Dart magazine full so her captain didn't have to worry about running out of missiles.


There seems to be some conflation of the various attacks on the Task Force.

25th May was the day that the TF was attacked by 2 Exocet carrying Super Etentards. That was the raid that sank the Atlantic Conveyor. The attack came from the North West and Invincible was bringing up the rear of the formation at that point, furthest away from the direction of attack. During that engagement Invincible fired 6 Sea Dart at what it thought were incoming aircraft or even Exocets but turned out to be chaff clouds put up by Hermes amongst other ships. Exeter was the most southerly of the picket destroyers and too far away to engage, although she did detect the Agave radars of the SE and flashed warnings (one source I have says she had been detached to carry out a bombardment that night which seems to have been cancelled).

30th May was the day that the Argentinians claimed to have hit Invincible, but their target was the frigate Avenger. The attack force comprised 2 SE (one carrying the last available air launched AM-39 Exocet, which both turned away after dropping the missile and giving a final course to the accompanying A-4C) and 4 A-4C with bombs. The TF was operating east of East Falkland and the attack force travelled around the southern side of the Falklands at some distance and made their attack on the TF from the south, to the surprise of the TF.

That day Invincible's Sea Dart was out of operation.

Exeter had been the West Indies Guardship at the outbreak of the Falklands War. It was only after the loss of Sheffield that she was ordered south on 7 May 1982. She sailed direct to Ascension Island, arriving on 14 May and then sailed on to join the TF off the Falklands, arriving on 21 May. I don't know how many missiles she had on board on 7 May or whether she ahd been able to replenish her magazine at Ascension.

On 30 May Exeter was the southermost Sea Dart escort (with Avenger to the south of her). Unlike her fellow Sea Dart ships, her computers had the latest software updates and a Captain well versed in electronic warfare which reportedly conferred a 15 sec engagement advantage over the others. Exeter's Type 1022 radar picked up 3 contacts to the south at 29 miles. Each of her Type 909 fire control radars locked on a separate target and she launched 2 Sea Dart missiles. The second of these took out one of the attacking A-4C (the first narrowly missed a Lynx helicopter on a surface search mission). Exeter then fired a third Sea Dart which may have taken down another A-4C. Another attacker was lost on the way in but in the confusion of the few minutes the action lasted may have fallen to Avenger's guns). Her Captain decided not to fire any more Sea Dart missiles at the retreating A-4C as Sea Harriers had been ordered to intercept and Exeter was down to 7 remainng Sea Darts and no expectation of receiving more in coming days.

On 9 June 1982 Exeter engaged 2 Gates Learjet 35A on recce over Falkland Sound, firing 2 Sea Dart. One missile was lost soon after launch. the other destroyed Learjet serial T-24 leaving no survivors from its 5 crew.
 

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My point about the Type 42 Sea Darts is that even against a feeble opponent such as Argentina that was deliberately trying to avoid Sea Darts is that missile consumption is high. Therefore stretching the Type 42 which almost doubled Sea Dart capacity provide a significant enhancement in combat capability, and with GTs this is possible without loss of performance. This is not the case with other ships like the County or Tiger.
 
Therefore stretching the Type 42 ... and with GTs this is possible without loss of performance. This is not the case with other ships like the County or Tiger.
There's a whole mass of issues which determine what the effects of a stretch on performance are - length to beam ratio, hydrodynamics, where it's inserted, trim, hull drag, etc. If you need to put more power into the water, then that's going to be true whatever the engine type, and if you need to expend more power, your fuel consumption will be higher, again whatever the engine type. The Batch 3 Type 42s ended up with a better hull form than the Batch 1s and 2s, and that's the major issue for their performance vs the earlier batches, not the type of engines.
 
There's a whole mass of issues which determine what the effects of a stretch on performance are - length to beam ratio, hydrodynamics, where it's inserted, trim, hull drag, etc. If you need to put more power into the water, then that's going to be true whatever the engine type, and if you need to expend more power, your fuel consumption will be higher, again whatever the engine type. The Batch 3 Type 42s ended up with a better hull form than the Batch 1s and 2s, and that's the major issue for their performance vs the earlier batches, not the type of engines.

All of that is true, however the Olympus marine GT could be had in 23,000-28,000shp versions. What's more by the time the later Type 22s were built the cruising Tynes were coupled with the high speed Speys (SM-3) rather than instead-of in the earlier Olympus and Spey SM-1 (HMS Brave) ships. So presumably the basic engines of the Type 42 could be stretched to 56,000shp in COGOG or ~65,000shp in a COGAG configuration.

IIUC the Tigers had a 'cruiser' propulsion whereas the Counties had half a 'destroyer' propulsion plus the 4 little GTs. If these ships required more power it's not a matter of just* fitting a more powerful version of the GTs, it requires something more drastic so can't be done 'lightly' the way it was with the Type 42 and Type 22.

*I have a theory that anyone who uses the the word 'just' doesn't understand the severity of the problem. :D
 
All of that is true, however the Olympus marine GT could be had in 23,000-28,000shp versions. What's more by the time the later Type 22s were built the cruising Tynes were coupled with the high speed Speys (SM-3) rather than instead-of in the earlier Olympus and Spey SM-1 (HMS Brave) ships. So presumably the basic engines of the Type 42 could be stretched to 56,000shp in COGOG or ~65,000shp in a COGAG configuration.

IIUC the Tigers had a 'cruiser' propulsion whereas the Counties had half a 'destroyer' propulsion plus the 4 little GTs. If these ships required more power it's not a matter of just* fitting a more powerful version of the GTs, it requires something more drastic so can't be done 'lightly' the way it was with the Type 42 and Type 22.

*I have a theory that anyone who uses the the word 'just' doesn't understand the severity of the problem. :D
You seem to be comparing the 'simplicity' of new-build Type 42 stretches (ie Batch 3) with the complexity of stretching an already built Tiger or County, and further justifying it with engine combinations that never went into a Type 42. Remember, a marine gas turbine isn't just the engine you hang under an airliner, there are considerable ancillaries to be fitted alongside - cf the Type 45 and the 'engine problems' that are actually in the intercoolers, not the WR-21s.

It was perfectly possible to reboiler and re-engine a steam-turbine powered ship as part of a rebuilding process cf the Kongo rebuilds , or to specify a higher power solution in a new-build.
 
You seem to be comparing the 'simplicity' of new-build Type 42 stretches (ie Batch 3) with the complexity of stretching an already built Tiger or County, and further justifying it with engine combinations that never went into a Type 42. Remember, a marine gas turbine isn't just the engine you hang under an airliner, there are considerable ancillaries to be fitted alongside - cf the Type 45 and the 'engine problems' that are actually in the intercoolers, not the WR-21s.

It was perfectly possible to reboiler and re-engine a steam-turbine powered ship as part of a rebuilding process cf the Kongo rebuilds , or to specify a higher power solution in a new-build.

I don't know how this line of thought ended up here as I'm not engaged with stretching the Tigers but rather how the Counties should have been made bigger, after all steel is cheap and air is free.

IIUC that mantra originated in the genesis of the Queen Elizabeth carriers and has been then more widely applied. I don't believe that this mantra is appropriate in the era of steam, it only became appropriate with the introduction of Gas Turbines.
 
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I don't know how this line of thought ended up here as I'm not engaged with stretching the Tigers but rather how the Counties should have been made bigger, after all steel is cheap and air is free.

IIUC that mantra originated in the genesis of the Queen Elizabeth carriers and has been then more widely applied. I don't believe that this mantra is appropriate in the era of steam, it only became appropriate with the introduction of Gas Turbines.
Generally speaking it was always true. Ships benefit from square-cube law; even the small increase of size results in significant increase in buoyancy.
 
Generally speaking it was always true. Ships benefit from square-cube law; even the small increase of size results in significant increase in buoyancy.

Sure, but the hull and structure isn't built in a vacuum, it has to be powered and power-plants in a large navy aren't bespoke to cater to every possible displacement. A destroyer would be sized around a more or less standard destroyer power-plant, which was about 54,000shp for Darings and 60,000shp for the Counties. Once a ship got too big for this standard engine it would have to use the standard cruiser power-plant, which IIUC was 80,000shp for the Tigers.

So steel is cheap and air is free only as long as the size suits a smallish number of standard propulsion configurations.
 
Sure, but the hull and structure isn't built in a vacuum, it has to be powered and power-plants in a large navy aren't bespoke to cater to every possible displacement. A destroyer would be sized around a more or less standard destroyer power-plant, which was about 54,000shp for Darings and 60,000shp for the Counties. Once a ship got too big for this standard engine it would have to use the standard cruiser power-plant, which IIUC was 80,000shp for the Tigers.

So steel is cheap and air is free only as long as the size suits a smallish number of standard propulsion configurations.
if it is only adding some length the L/B ratio offsets a bunch of need for a more powerful plant.. as has been pointed out Gearings had the same plant and installed power as the Sumner's and same speed, Counties should be fine
 
Post 92 from the thread "RN Tiger class options".
None of the GW cruiser studies during 1954-55 had Type 965.
The Staff Requirement for a Type 960 replacement was raised in 1950 but the selection of Marconi's design wasn't made until 1955 (beating the AN/SPS-6C, LW-02 and a slower-rotation Type 992 proposal). It seems to have been earmarked for air direction frigates at that stage.

Between September 1954 to January 1955 the cruisers in the GW series either offer Type 984 or Type 960, but after Jan 1955 Type 960 is dropped entirely and it becomes either Type 984 or reliance on Type 992. The GW Destroyer did though gain the 965 over the earlier 960 as the design firmed up during 1955.

I share your suspicion that CDS and DPT were lacking in these Fiji conversion studies.
I'm posting the above because the Type 984 is too heavy for the County and Tiger. Therefore, we're stuck with the Type 965 unless a better radar that's light enough for the ships that had it IOTL could have been developed.

Type 965 entered service on the Weapon class when they were converted into interim fleet pickets (1956-59) and the next class to have it was Type 81 which came into service from 1961.
 
I'm coming to the conclusion that the Type 984 isn't overly suitable for the County or Sea Slug equipped class, a 3D search radar coupled with a 2D TI radar seems back to front. The usual practice is a 2D search radar coupled with a 3D TI radar where possible. Its probably better suited to the ASW helicopter converted Tigers to direct flight operations, but it appears there's no room.
 
I'm coming to the conclusion that the Type 984 isn't overly suitable for the County or Sea Slug equipped class, a 3D search radar coupled with a 2D TI radar seems back to front. The usual practice is a 2D search radar coupled with a 3D TI radar where possible. Its probably better suited to the ASW helicopter converted Tigers to direct flight operations, but it appears there's no room.
A Seasug ship on the light carrier hull (Leviathan, yep), on the other hand, would be more than capable of carrying Type 984.
 
Therefore stretching the Type 42 which almost doubled Sea Dart capacity provide a significant enhancement in combat capability, and with GTs this is possible without loss of performance. This is not the case with other ships like the County or Tiger.
Stretching the Type 42 did not double the magazine capacity - the Batch 3 ships had the same 22-round magazine as the earlier batches. I've seen mentions that space was reserved for another 15 missiles, but no evidence that the magazine extension was ever made or how that would have realistically worked given the hull stretch was forward of the Sea Dart launcher and magazine. The extension was to improve seakeeping (keeping the Sea Dart further away from bow spray).

Anyhow, we seem to be straying far from the topic of this thread.
 

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