Royal Navy Escort Cruiser 1962

[uk 75]

The two recent books on post-war British ships (Brown and Moore-Rebuilding the Royal Navy and Norman Friedman’s British Destroyers and Frigates) give numerous descriptions of ships for which there seem to be no drawings or illustrations.
The most interesting (because there are so many drawings of previous and later variants) is the Escort Cruiser, which was postponed in 1962 because of the purchase of Polaris.
The planned design (SCC 36A) was for a 10,000 ton ship armed with two Seadart launchers (SAWG) and one Ikara (ASWG) launcher, and carrying 4 Chinook ASW helicopters. It derived from the ship with Seaslug and 4.5” gun widely illustrated with a through deck design. It was the starting point for the 1966 designs which led to the Invincible class CAH.
The ships planned (with completion dates and replaced ships)were:
EC 01 1969 (9th County)
EC 02 1970 (10th County)
EC 03 1971 (Tiger)
EC 04 1971 (Blake)
EC 05 later (Lion)
Such specialised ships would certainly have been better value and more capable than the Tiger conversions, and probably not much more expensive. So it’s a shame that no plans or illustrations of the final design seem to exist.

 

[smurf]

Some guesses. This may be falling foul of the thirty year rule on release of documents. I know it is longer than that, but not all documents are released at once. It depends on urgency and interest, as well as any continued sensitivity, and even when released it can take some time (years?) for them to be catalogued and made available for public access. Staffing levels are also a problem. I've just got an awkward (they said) ship plan from 1921 out of the PRO that I first asked for last October, my first contact leaving, I suspect unreplaced. Drawings of other projects like yours often originate from designers' workbooks. The 30 years may not start to clock up until that designer has retired and the workbook is finished with and archived. Perhaps someone who really knows how these things work can tell us.

 

[Mike Pryce]

Perhaps someone who really knows how these things work can tell us.

I was told at the PRO that the 30 year rule no longer applies, as the Freedom of Information Act now has primacy. I made a number of requests for file from years up to 1988, all on defence topics, and got them all released. So perhaps it is worth asking the MoD for the plans, which I assume would be at Greenwich.

 

[smurf]

That's interesting. But I was led to believe that the rule still applies in practice to the general release of documents, as there is a process and routine for dealing with the vast quantities of paper. Perhaps if you know what to ask for?
Out of interest I've just done a search on the PRO (beg its pardon, National Archives) catalogue, for "Cruisers 1960 - 2007". The ADM reports stop at 1977.

 

[Mike Pryce]

My understanding is that most of government is still set up for the thirty year rule (e.g. transferring files to PRO/NA) but that it is no longer the case that this means they are must be secret for that time. Rather, that is what happens if they are not asked for beforehand.

To make an FOI request you write to the relevant organisation (e.g. MoD) and they are supposed to respond, either releasing the file to Kew, sending you a photocopy, telling you to go away etc.

 

[smurf]

I expect you do have to know which documents you want to have released. I wanted a missing diagram from an ADM1 paper of 1921 published on the HMS Hood Association website. I now have it, five months later, after starting with an expensive quote for the whole file. The delay was in part due to staff problems, illness, but you have to stick with it, it seems.

 

[Thorvic]

Just to get back on Topic, has anybody checked the file in the PRO of the 1962 Escort Carrier design, Brown & Moore quote the reference used for their description of the revised design ?. Its quite possible the book authors went with the original 1961 drawing to illustrate the hybrid development of the Escort cruiser from County class Destroyer to Invincible class carrier.

Going by the way its described in the text, Ralph has suggested that the design may have changed to a format similar to the original CVA-01 design with the Angled full length flightdeck and sea dart on each quarter.

The later design makes no mention of a gun so i wonder either the Ikara or Sea Dart was to be located in its former position, as a Escort cruiser i cant imagine they would place all the weapons around the stern as it is an Escort wheres as with CVA-01 they were intended for self defence.

(I'm currently building the 1961 version of the design in 1/700 scale as that has dimensions and drawings that are suitable, however i would like at some point to try the 1962 design should any artwork be found)

Geoff

 

[JohnR]

For the era of these ships, the Sea King was virtually if not the actual then the projected standard large ASW helo of the Western Navies, why was the Royal Navy specifying Chinooks, were there any other proposed uses of the Chinook in an ASW Role.

With regard to the statement regarding the side by side mounting of the Sea Darts, given the more elaborate magazine arrangements of SD when compared to Tartar/Standard, would there have been sufficient volume tow aft. Also even given the greater freeboard I would imagine for this type of ship, I would imagine problems with the shaft runs.

I have wondered about an Invincible with "full" carrier facilities at the bow (a la Princip de Austurias and Garibaldi) and the SD in a cut down aft. How would the aviation capability vary with that type of arrangement.

 

[TinWing]

For the era of these ships, the Sea King was virtually if not the actual then the projected standard large ASW helo of the Western Navies, why was the Royal Navy specifying Chinooks, were there any other proposed uses of the Chinook in an ASW Role.

There was a proposal for a British equivalent to the Chinook, the Westland WG.11, which oddly enough was similar and configuration to the CH-47. The one oddity was the use of 4 RR Gnome turboshafts.

 

[Thorvic]

For the era of these ships, the Sea King was virtually if not the actual then the projected standard large ASW helo of the Western Navies, why was the Royal Navy specifying Chinooks, were there any other proposed uses of the Chinook in an ASW Role.

There was a proposal for a British equivalent to the Chinook, the Westland WG.11, which oddly enough was similar and configuration to the CH-47. The one oddity was the use of 4 RR Gnome turboshafts.

BTW It was proposed in the Sixties when the UK first looked at Chinook that it would have been fitted with 4 Gnomes in twin engine pods in place of the existing engine pods. AFIAK the Chinook was actually ordered in the mid/late 60's for the RAF to replace Belvedre for transport duties but the orders was cancelled with the complete withdrawal from East of Suez (Serial codes were assigned to the aircraft ordered XV840-XV855). A second attempt to buy Chinook was done in the early 70's also failed before they were finally ordered in the late 70's.

The Royal Navy was looking at Chinook for ASW work as the twin rotors make them very stable in the hover when dunking sonar, plus its lift capability would allow for a decent ASW suite and weapons to be carried, although its shear size probably meant it wasn't really practical.

Still will be nice to model one in 1/700 especially in the RN colours - hmmn Overall RAF Blue Grey or Blue Grey with Yellow uppers ?

 

[uk 75]

Brown/Moore's account of the 1962 escort cruiser which was
nearly ordered until Polaris caused its postponement is very
frustating. I have not been able to check the source in the
Records Office but a friend of mine who has looked at these
files thought not all the drawings had been preserved.

Given that the ship came so close to being ordered it is odd
that no picture, model or drawing of it in the form of 1962
has survived.

I agree that my speculation based on the CVA 01 drawings
is just that. Also it should be noted that the 2 Seadart and
Ikara version of CVA 01 was dropped fairly quickly in favour
of the single Seadart configuration. In which case the 1962
Escort Cruiser design is best represented by the drawings
on the two pages about the Fleet working party schemes in
Brown/Moore.

However, for a brief period the RN flirted with a CF299 double
set in both its carrier and escort cruiser. I shall keep looking and asking.

UK 75

 

[smurf]

a friend of mine who has looked at these files thought not all the drawings had been preserved.

It is not unusual (at least in older ADM documents) to find some envelopes labelled as containing drawings, but in fact empty.

 

[JohnR]

I agree that my speculation based on the CVA 01 drawings
is just that. Also it should be noted that the 2 Seadart and
Ikara version of CVA 01 was dropped fairly quickly in favour
of the single Seadart configuration. In which case the 1962
Escort Cruiser design is best represented by the drawings
on the two pages about the Fleet working party schemes in
Brown/Moore.

UK 75

The image in Brown/Moors book show an early version of CVA01 with a the more conventional angled flight deck with the two SD launchers and Ikara, and then the parallel deck version with single SD but still retaining Ikara. Was there a variant of the parallel design with two SD's?

Regards.

 

[Longshaor]

It is not unusual (at least in older ADM documents) to find some envelopes labelled as containing drawings, but in fact empty.

In addition to what Smurf said, the drawings could also be filed incorrectly. An aquaintence of mine told me several years ago of an annoying correspondance with the NMM over the drawings for the Malta class carriers. The drawings in the folder for the Malta class were actually the Audacious class, and the NMM had no idea where the correct drawings were. They helpfull offered to search their archives - for £50 an hour!

Cheers

 

[JohnR]

I would happily offer to do that at a much reduced rate :!!!!

 

[smurf]

JohnR said

I would happily offer to do that at a much reduced rate !!!!

You might change your mind after a few days fruitlessly opening heavy boxes and unrolling large plans!!! Malta's would be about 8feet long. But they are not likely to let you, even as a volunteer, because many of the early plans are no longer in good condition, and need handling carefully. It may take two staff to open them. Even Malta's would be 65 years old. I've had the frustrating experience of actually finding a tracing I wanted to see, and being unable to look at it, because it would have fallen apart if we had tried to open it. It may then go away for weeks into "conservation" but only if it is worth the expensive effort to preserve it.
Seriously, though, once something is misfiled in a large collection, finding it by search may be virtually impossible. Realistically you just have to wait for it to turn up, and it may not even be there at all. The plans at NMM came from the Admiralty, as did those at TNA, about 30 years ago I think. At NMM the plans are rolled up several to a box, one or more boxes per RN ship back to the year dot. The contents of the boxes are not yet catalogued in detail. I think they have got to somewhere in the early 1800s. NMM's two staff in that department have a lot more to do than look for the missing, though they do try if there is a likely place. I've won a few Brownie points there by putting marker sheets in the Ships Covers when taking out a drawing to be copied. Saved them a lot of time when putting it back if they don't have to hunt for the place. But then I used to run a technical library, with a smaller and more easily handled stock than theirs, and six staff, so I'm sympathetic. The French archives started to scan their plans, and put them on-line, but that has stalled for lack of money and staff.

Now I've got started, I recently found on-line that there was a dockyard plan of HMS Hawkins in the Medway Archives, relating to its state before the final armament layout was settled. Now the original Hawkins Ships Cover with details such as that was lost (in a fire during the war, when the design offices in Bath were bombed, I think) and only a late reconstruction from other sources exists, (which DK Brown compiled, IIRC) with nothing on the initial design history. Medway Archives are not far from NMM, so I went to look at it. (I'm working on a book on British cruiser designs). It was dated, written over the dockyard stamp, May 1916 - a 9000ton unnamed two-funnelled cruiser, as was Hawkins, built then at Chatham down the road. It turned out to be HMS Blake, in her early state before her armament was finalised, in 1889 - probably the very plan the designer sent to Chatham dockyard in advance, to get construction started. So I'm still looking for Hawkins, but what chance had anyone of finding Blake except by accident? Someone knowledgeable at Medway might have spotted it, but it is the only ship plan they have, and again at some 8ft long, rarely opened.

 

[Longshaor]

Smurf, I had heard that the reason the French collection was pulled was that the site had become a popular target for hackers.

In any event, I suppose with a staff of 2 there's no chance of the NMM digitizing their collection, though it would make sense from the preservation perspective. In my job I've worked on sites where the only drawings we've had were old-style blueprints from the 1930s. Those don't hold up well over time and one of our jobs was to scan the things so when the paper finally deteriorates the information is still preserved. It's a time consuming operation, but when your talking about a national museum, I think it's a disservice to the tax/rate payers not to preserve the nation's history.

Cheers

 

[smurf]

I'm sure Bgire won't mind me posting this across from Warship Projects about the French archives:

I'm afraid the new site is at the present "dead in the water", waiting for more time, or funds, or staff.
All those who are interested in those plans for historical research can help in sending request about the plan availability by filling the sheet here :
http://www.servicehistorique.sga.defense.gouv.fr/Suggestions-et-rclamations.html
I think the more requests will come from us from everywhere, the more chance we'll have to get this site back.
So please, help us!

when your talking about a national museum, I think it's a disservice to the tax/rate payers not to preserve the nation's history.

NMM is spending a £20million gift on a new wing at Greenwich to have much improved public access and attractive displays.
http://www.nmm.ac.uk/about/partnerships-and-initiatives/sammy-ofer-wing/directors-introduction
Meanwhile they are having to cut staff. Preservation starts with the oldest, most vulnerable materials. It will be a long time before they get to the plans and Covers at Woolwich. I've felt a bit guilty looking at some 19th century stuff, and seeing the bits of page edges on the table afterwards. Nothing vital, but the next but one time, some data will bite the dust.
"About us NMM" begins thus:

The National Maritime Museum comprises three sites: the Maritime Galleries, the Royal Observatory and the Queen's House. Together these constitute one museum working to illustrate for everyone the importance of the sea, ships, time and the stars and their relationship with people.

Those three are all at Greenwich. The Historic Plans and Photographs section, with the collection of Ships Covers, is at Woolwich Arsenal. I think that says it all.

 

[Hood]

Had a look through Friedman's 'British Carrier Aviation', he follows the helicopter cruiser from 1960 to 1970 when it became Invincible.
However interestingly he makes no mention of the 1962 design at all apart from one line, "There was some expectation that such a ship would be included in the 1962-63 Naval Estimates, but this did not occur; perhaps the board preferred not to propose an expensive small carrier-like ship while it sought funds for the full sized CVA-01. Then it seems all worked stopped until 1967 when the Study 23 design came out as illustrated by me elsewhere on this forum.

Friedman offers us a new excuse, the fact the staff wanted CVA and knew the politicans would jump on the CVA in favour of the cheaper Escort Cruiser. Perhaps there was never a real intention to order such a ship until the CVA was under way with metal cut. Polaris is a convient excuse to delay the ship when the CVA is the overall more important project behind Polaris.

Friedman makes no note of the design or armament but seems to imply the design was based on the 1961 through-deck design (the sketch scheme is in the book) being "carrier-like". Interestingly it was designed in late 1961 so is close to the 1962 date. Obviously at a later date it was decided to ditch Sea Slug in favour of Sea Dart (begs the question why bother with Sea Slug at all in these designs when NIGS and SIGS is under study). I think it very likely to resemble the 1961 design with Sea Dart aft (like CVA-01) since there would be no need for a total redesign and it does resemble a mini-CVA-01 in many ways.

 

[JohnR]

Obviously at a later date it was decided to ditch Sea Slug in favour of Sea Dart (begs the question why bother with Sea Slug at all in these designs when NIGS and SIGS is under study).

Maybe it was a case of a "bird in the hand is worth two in the bush", the parameters for Seaslug were already known?

 

[uk 75]

Brown/Moore Rebuilding the Royal Navy is a much
more detailed account of the 1962 Escort Cruiser
than in the much earlier Friedman British Aircraft Carriers.
A whole page is devoted to the process for ordering
the ships and cancellation is firmly attributed to
Polaris costs rather than carrier procurement. It also
serves to link the sudden appearance of the ghastly
Tiger class helicopter conversions as "interim" escort
cruisers for replacement in the 1970s.
The evolution from Seaslug to CF299 (Seadart) is matched
by the story of the final County class destroyers which had to
be ordered with Seaslug because of delays in CF299 development.
By 1962 it was probably felt that like CVA 01 the escort cruisers
would not come into service until after the first of the CF299
frigates so Seaslug could be dropped.
There remains no published drawings of non Seaslug/CF 299 ships
from 1956 onwards other than references in Brown/Moore and
Friedman's British Destroyers and Frigates. There must be some
sketches somewhere.

UK 75

 

[smurf]

There must be some sketches somewhere.

A guess. Under the 30 year rule, such drawings if any would not be released until the mid 1990s or later. I believe by then release of Admiralty (or armed forces generally) documents to National Archives had become less certain, and slower, or wasn't happening at all.
One route might be a request under the Freedom of Information Act for documents to be released, but I think, in order to initiate the checks on whether they can be released under FoI, you need to identify specific documents, which puts us back to square one.
I've tried a few searches in the TNA catalogue, but found nothing looking at all likely.

 

[JFC Fuller]

Friedman's British cruisers gives the best account I have seen of this vessel and it also fits with what I have seen whilst reading about CVA01, unfortunately still no drawings of the Sea Dart/Ikara ships that came from 1962 onwards.

The summary of the story is that the "escort cruiser" started out as a straight replacement for cruisers but with helicopters, when it was decided that British carriers (including the early CVA01 design) would not carry organic ASW helicopters they became the escort cruiser that we know and love; however, when CVA01 was redesigned and enlarged it took on its own ASW helicopters so the escort cruiser reverted to its original cruiser role and seems to have lost importance though it remained in the long term plans with the idea being to convert Tiger, Lion and Blake as interim measures, this gets difficult though because Friedman goes on to state that the converted ships could not enter service until the carrier force had been run down so it is unclear to what extent CVA01 and the helicopter cruisers ran concurrently after the CVA01 redesign.

A single Sea Dart launcher was inevitable as it was cheaper to two reasons, firstly it only needed one launcher which was thus cheaper and secondly it could use the system being designed for destroyers rather than a bespoke system- that was one of the main reasons for moving to a single system on CVA01. It is very difficult to see how these ships could have been built with Sea Dart, Type 988, Ikara and and an air-wing of 8 Wessex or 5 Chinook on 10,000tons. Indeed the displacements we see primarily come from the same time-frame when Bristol was being conceived as a 4-5,000 ton vessel and ultimately emerged at over 7,000 tons so any helo cruiser would likely have come out at 12-14,000tons.

In terms of configuration the only thing I can really imagine being practical is a through-deck design with a CVA01 style superstructure, Sea Dart on the bow (like Invincible) and Ikara on the stern in a Niteroi style fantail configuration; the missile locations could be reversed but I really don't see any other way of doing it.

 

[Abraham Gubler]

In terms of configuration the only thing I can really imagine being practical is a through-deck design with a CVA01 style superstructure, Sea Dart on the bow (like Invincible) and Ikara on the stern in a Niteroi style fantail configuration; the missile locations could be reversed but I really don't see any other way of doing it.

At this time (1962) the RN was thinking the Sea Dart launcher could also fire Ikaras. There are some drawings of early AA frigates with a combined launcher with Sea Dart vertical magazine beneath and Ikara horizontal magazine behind.

See this thread here:

http://www.secretprojects.co.uk/forum/index.php/topic,5525.0.html

Except I didn't attach the picture of the combined launcher ship. I will look it up in my archive because the middle watch webpage has been dead for sometime.

 

[Abraham Gubler]

Here is the ship plan of the 1962 RN frigate with forward and aft launchers for both Sea Dart and Ikara. I will update this in the original thread as well.

 

[JFC Fuller]

Not really relevant to this thread, that is clearly a very early Type 82 configuration whereas this thread is about the Cruiser/Escort Cruiser/Helicopter cruiser studies. It should probably be put in a separate Type 82 thread. It is a shame that the website that that image originates from seems to have undergone some changes (including a new web address) and is no longer showing the image though as it had a number of others from the same series that demonstrated this is just a very preliminary sketch of just one configuration out of many under consideration (this is Fig 6.7 so there are at least another 6 in the series) at the time.

 

[Brickmuppet]

It does show that the RN was considering a dual purpose launcher like the later US MK26 in this timeframe. That might have been more closely looked at if the Escort Cruiser had proceeded as it might have simplified some things.

 

[JFC Fuller]

It does show that the RN was considering a dual purpose launcher like the later US MK26 in this timeframe. That might have been more closely looked at if the Escort Cruiser had proceeded as it might have simplified some things.

I would suggest not really, Mk26 was great because it used a single magazine for ASROC, Harpoon, and Standard, this proposed launcher uses two separate magazines and looks like it would cause as many design headaches as it would solve from a ship perspective. It also seems to have been abandoned fairly quickly. The rest of this series of drawings show a range of different configurations, this being the only one, that has made it online, with a dual purpose launcher.

 

[Abraham Gubler]

Not really relevant to this thread, that is clearly a very early Type 82 configuration whereas this thread is about the Cruiser/Escort Cruiser/Helicopter cruiser studies. It should probably be put in a separate Type 82 thread.

As mentioned in the previous posts I have updated this image into the thread on this series of RN frigate designs from 1962. Also as mentioned the whole point of adding this picture here was to illustrate the arrangement of the single launcher for Sea Dart (CF.299 at this time) and Ikara magazines.

Which is actually hugely relevant because that is what DK Brown and George Moore (Rebuilding the Royal Navy) say was to be incorporated into the 1962 design of the Escort Carrier:

“By July 1962 the ships had been redesigned. The alterations were substantial, for 4 Chinook-type helicopters were to be carried. The weapons were also modified, with two launchers for the new Sea Dart (CF299) guided missiles and the Ikara anti-submarine weapon system installed.”

 

[JFC Fuller]

Unfortunately DK Brown's statement is not that clear, it can be read that way or it could be read that there were to be two Sea Dart Launchers and an Ikara system (entirely plausible if not probable given the early CVA01 configuration) or it could be saying that there was one launcher for Ikara and one for Sea Dart. Friedman gives the design 2 Sea Dart systems and Ikara so the last option can probably be ruled out. The answer is probably the same as why we do not have a picture of the final 1962 design, one has not been found in the archives and all that remains is an unclear text document.

Either way, this is a Type 82 (very) preliminary in a thread about the escort/helicopter cruiser.

 

[Abraham Gubler]

Unfortunately DK Brown's statement is not that clear, it can be read that way or it could be read that there were to be two Sea Dart Launchers and an Ikara system (entirely plausible if not probable given the early CVA01 configuration) or it could be saying that there was one launcher for Ikara and one for Sea Dart. Friedman gives the design 2 Sea Dart systems and Ikara so the last option can probably be ruled out.

Yes but only with the generally accepted poor use of English we all get by with today. I am however inclined to think that Brown and Moore would be more precise as their book and others by Brown have only the highest standards of English throughout.

They say “with two launchers for the X and the Y installed.”

For two Sea Dart and an Ikara they would have said: “with two launchers for the X and another for the Y installed.”

For one of each: “with a launcher for X and another for the Y installed.”

Then as good historians we can add context to the interpretation. Which is that at the same time the same people were designing a ship with a launcher that could fire both missiles. Also the reason they designed such a system was to cut down on the length required to install double ended Sea Dart with Ikara on a single ship. For the SCC39A escort cruiser the need to reduce length allocated to missile launchers would be extreme (so as to fit in the flight deck and hangar).

Of course without a drawing or more detailed description it requires interpretation but it is still as viable as any other. And certainly more viable than some of the conjecture in this thread.

Either way, this is a Type 82 (very) preliminary in a thread about the escort/helicopter cruiser.

Yes and again, for the third time, only here to illustrate its magazine/launcher arrangement.

 

[JFC Fuller]

Please be inclined to think that, however the statement is unclear.

As good historians we should certainly use context. And every theory has multiple facets, this drawing is dated February 1962 and seems to have been produced prior to the British decision to adopt Ikara (we know this as Friedman states the RN decided to adopt Ikara in 1962 and the other drawings in this series show designs with Malafon and ASROC). We also know that these are very preliminary designs, both because of the 1962 date and because the first Sketch Staff Requirements were written in early 1962. Friedman also states that by that stage design armament was 20x Ikara and 38 Sea Darts, unless the RN was planning on Seadart magazines with odd numbers of missiles or two magazines with unequal Seadart load-outs (unlikely) it suggests very strongly that the double-ended configuration along with the dual launcher concept had already been rejected (along with ASROC and Malafon). We also know that by December 1962 (and almost certainly before) CVA01 was using separate Seadart and Ikara launchers which again suggests that the dual launcher idea had been thoroughly rejected by late 1962. Furthermore we know that the escort cruiser was inserted into the 1963 long-term plans and was considered for the 1964 long-term plans (when it was deferred) so the vessel remained under discussion right through 1963- after the dual launcher appears to have been abandoned. In addition, CVA01 gives us an alternative configuration for a Sea Dart/Ikara layout on a through-deck ship in exactly the same time-frame.

It is also worthy of note that the dual launcher sketched in the February 1962 Type 82 preliminary actually extends the length of the installation considerably as the Ikara magazine and assembly rooms extend backwards some way beyond the rear of the Sea Dart magazine below the launcher itself thus achieving quite the opposite of reducing the length allocated to missile launchers.

Of course, without a drawing or more detailed description it requires interpretation but it is still as viable as any other. And certainly more viable than some of the conjecture in this thread.

 

[Abraham Gubler]

It is also worthy of note that the dual launcher sketched in the February 1962 Type 82 preliminary actually extends the length of the installation considerably as the Ikara magazine and assembly rooms extend backwards some way beyond the rear of the Sea Dart magazine below the launcher itself thus achieving quite the opposite of reducing the length allocated to missile launchers.

That’s not correct. Length consumption in ship design is about the deck surface area consumed by a system. The horizontal Ikara magazines allow for stacked designs. They can have director houses fitted on top of them and even a bridge. But by dual use of the launchers there is no need for a separate Ikara launcher. Which is what consumes the ship length.

As to your arguments about this launcher configuration not being pursued it has a lot of ‘maybe’ and ‘probably’ but no actual evidence. The magazine design is for a length constrained double ended ship. Since this CF.299 frigate option and the escort cruiser in 1962 the RN didn’t pursue a double ended ship until the Type 43 in the 1970s by which Ikara wasn’t specified. The only other ships with both Sea Dart and Ikara have their own reasons for separate launcher arrangements. Like early CVA-01 configurations not wanting a magazine arrangement which would conflict with the hangar and Type 82 not having the space near the aft Sea Dart launcher thanks to its nearby gas turbine intake and exhaust requirements.

 

[JFC Fuller]

That’s not correct. Length consumption in ship design is about the deck surface area consumed by a system. The horizontal Ikara magazines allow for stacked designs. They can have director houses fitted on top of them and even a bridge. But by dual use of the launchers there is no need for a separate Ikara launcher. Which is what consumes the ship length.

Actually it is entirely correct, internal length is rather important, for things like crew accommodation, hangars, operations rooms, machinery spaces, exhausts, uptakes, and for developing a design with structural integrity; basically for actually designing a ship, the process would be much easier if we only had to worry about deck surface area but of course life is never that easy as you rightly point out with CVA01 and in your earlier reply #30 with regards to the escort cruiser and its hangar. The dual launcher design is actually very inflexible from a design perspective as the Seadart and Ikara magazines have to be precisely correlated and between them take up a remarkably large and awkward space. The Ikara apparatus in particular clearly adds greatly to the length of the total system, indeed the drawing shows that the Ikara magazine, assembly rooms and loading bay extend well to the rear of the Seadart magazine. By separating Ikara into a separate launcher it becomes much easier to locate all three systems which is exactly what was done with CVA01 as you state, and for that matter with the Type 82 which was the outcome of the very preliminary design drawing you posted.

As to your arguments about this launcher configuration not being pursued it has a lot of ‘maybe’ and ‘probably’ but no actual evidence. The magazine design is for a length constrained double ended ship. Since this CF.299 frigate option and the escort cruiser in 1962 the RN didn’t pursue a double ended ship until the Type 43 in the 1970s by which Ikara wasn’t specified. The only other ships with both Sea Dart and Ikara have their own reasons for separate launcher arrangements. Like early CVA-01 configurations not wanting a magazine arrangement which would conflict with the hangar and Type 82 not having the space near the aft Sea Dart launcher thanks to its nearby gas turbine intake and exhaust requirements.

The fact that a CVA01 configuration in this period used two Seadart launchers and one Ikara launcher, the fact that the UK seems to have abandoned the dual launcher very quickly (which is why Type 82 is not doubled-ended, the dual launcher could have made it double ended but that configuration was clearly abandoned) and as you say- using separate launchers would allow for magazine arrangements that conflicted less with hangars and flight decks, this applies to the escort cruiser exactly as you stated in reply #30 as well as CVA01 suggests we have plenty of evidence. As we see from the picture the proposed dual launcher actually makes the length constraint more severe rather than alleviating it and makes locating the launchers far more challenging due to the need to align with two separate magazines with loading points almost at right angles to each other.

 

[Abraham Gubler]

Actually it is entirely correct, internal length is rather important, for things like crew accommodation, hangars, operations rooms, machinery spaces, exhausts, uptakes, and for developing a design with structural integrity;

No you’re still extremely wrong. In warship design 101 the two most crucial issues are stability and deck surface area. The later to fit in all the weapons, sensors and in/up takes. Since 98% of sub-systems in a warship are arranged vertically and because warships have high length to width ratios this deck area constraint is almost always communicated as length. This issue being so crucial to ship capability that USN costing predictions use length as a major input.

Consult any naval architect or read any treatise on it from Friedman to Brown and length will come up as the key issue in determining capability. Or even look at the 1962 CF.299 frigate designs and see how many more weapon systems can be fitted in on the ship with the dual missile launcher to notice the efficiency gain in length.

basically for actually designing a ship, the process would be much easier if we only had to worry about deck surface area

That was not what I said nor could any reasonable interpretation deduce that.

As far as I’m concerned this conversation is over. You can follow your set routine and ignore this input and post again but I won’t bother with another reply. I’m sure the greater majority of readers of this thread get the point.

 

[JFC Fuller]

No, I am still extremely right. Warship design is infinitely more complex than that and has to take into account multiple variables. Even stability is going to be determined heavily by the distribution of internal weight which will itself affect structure and machinery. It is precisely that incredibly complex and circular process that Brown, Moore, Daniel and Friedman all do such a good job of explaining and the end result is always a compromise over armament, range, hull form, machinery, structure, internal volume, manpower, materials, cost etc, etc. Also, my inference of your meaning was entirely reasonable, thank-you for the clarification though.

It is also impossible to read anything about the efficiency of the dual missile launchers from the February 1962 general arrangement drawings as they are so lacking in data. They do not give us any dimensions, either of the ships or their magazines or the ships themselves, they do not tell us the effects on performance of each configuration etc. The only thing that is clear is that the super-structure of the dual launcher version has had to be made much larger than the other versions under study (with the possible exception of the forward ASROC aft Seadart arrangement) due to the necessity to correlate the Seadart and Ikara magazines; which will of course come with its own set of issues.

 

[Hood]

Eric Grove's Vanguard to Trident gives a bit of info.

He says the original plan was a 6,000 ton gudied-missile cruiser with capacity for nine Wessex ASW helicopters as an escort for CVA-01 (he says it had, at time of CVA cancellation, been under development for some time so must be the 1962 design). He sees the end of CVA-01 enlarging the design to include command spaces etc. to serve as a command ship instead of the CVA as the centrepiece of a battlefleet. ASW would be handled by Sea Kings. Design then went into two directions; "a 12,500- ton cruiser of more or less conventional layout with an upper hangar deck for six Sea Kings (a larger version of the Vittorio Veneto concept) and a more radical 17,500-ton carrier-like "through deck" ship with a larger hangar for nine helicopters from the top of which the aircraft would fly." In early 1967 a sketch Staff Requirement was raised and government approval was given in mid-1967 and the First Sea Lord, Sir Varyl Begg was against the small carrier proposal and rejected the Future Fleet Working Party Report, so the 1967 ship was the conventional design. The VCNS Vice Admiral Sir Peter Hill-Norton, a gunnery officer, also supported this.
In 1968 however, a change of First Sea Lord to Sir Michael Le Fanu, and the new junior minister Dr. D. Owen, switched the option to the "through deck" type and Naval Staff Target 7079 was written up. Detailed studies of both layouts were drawn up, the Study 21 and Study 22. The through-deck 22 was enlarged as the 18,750 ton Study 23 and ten helicopters were considered ideal to have 4 flying at all times. When Hill-Norton was replaced bySir Edward Ashmore the balance was firmly in favour of the through-deck and in 1970 a full Naval Staff Requirement was drawn up for a Through Deck Command Cruiser (TDCC). Owen and Le Fanu avoided calling the ship a carrier, but already by 1969 Owen in Parliament had been hinting at Harrier operations - either by the RAF or FAA.

So what does Eric Grove's account tell us?
The cruiser had been underway for some time, and that it was purely for the escort role. It seems the "through deck" layout did not appear until after/around the time of the cancellation of CVA when the design evolved to take on some of CVA's C&C roles. So it was probably much closer to a conventional design, perhaps like Type 82 with Sea Dart forward. Beedell's Future Navy site has a picture of Study 22 as an escort ship but this is obviously incorrect, Study 22 was after CVA was dead. Where Ikara was is open to question, probably the stern was a helideck. The further enlarged 12,250 ton design of 1966 is described as being like Vittorio Veneto, at first I thought an upper deck hangar meant an above deck conventional hangar, but perhaps it really was an underdeck hangar with lift, like the Italian ship. That opens the possibilty of a double-ender design, notably all RN ships had Ikara forward so perhaps we should assume that layout. Grove describes it as "more or less conventional" so presumably it wasn't anything radical in layout, certainly higher freeboard aft than most postwar RN ships.
Interesting it tells us that personalities as much as the practical nature of the "through deck" was the primary concern. Only a change of leadership enforced a change of attitude towards the carrier-like design. So the 1962 design must have lived on into the Study 21, I see more of an evolution of increasing size than anything.

Interestingly Grove must have seen some kind of sketch design for the 1966 ship to make his assessment that it was like a Vittorio Venteo, unless his basing that upon written descriptions, but he only quotes secondary sources for his info, D.K. Brown's 'Century of Naval Construction' and International Defence Review vol. 6 no.6 1973 'The Through Deck Cruiser Concept'.

 

[JFC Fuller]

Hood,

Vanguard to Trident is an excellent book but it must be remembered that it was published in 1987 when only a fraction of the material available today was accessible, indeed if you check the reference for Grove's narrative on the command cruiser he actually lists only public sources (Jane's and other author's books), this is in no way a criticism of Grove's work it is just a simple reality of the time in which he was working, he is also presenting a far wider story than the narrow development of particular ship types so tends to truncate those elements. It is remarkable is how close to the truth he got though. However, since then much more material has become available that has shed far more light on this tale. In particular Friedman's British Cruisers and D.K. Browne & George Moore's Rebuilding the Royal Navy. I gave a summary of this in reply 22 in this thread. Just to add to that, as you mentioned study numbers:

The series 21 seems to have been the first actual escort cruiser, series 9 & 6 having been designed to destroyer standards, and also seems to have been the most studied. It is likely that a series 21 derivative is our illusive Sea Dart and Ikara ship.

Later, for the Invincible class, there were three initial studies, 21, 22 and 23. Study 21 was a 10,000 ton vessel (and looked Vittorio Venetoesque), study 22 was 17,500 tons and study 23 was study 22 with provision for a bottom bounce sonar adding 1,200 tons. Study 22 was chosen for further development (bottom bounce sonar was abandoned and study 21 had insufficient helicopters) and it was found it could be scaled up to carry more helicopters for relatively little expense. D.K. Browne says that study 23 was chosen though I am inclined to believe Friedman as his publication is newer and it agrees with the study 21,22,23 line drawings in Rebuilding the Royal Navy!

I can not find any drawing on the Navy Matters site (I might be mistaken) labelled Study 22; he has two line drawings relevant to this thread, the first being what looks like design 21M3 in the "Escort Cruisers" section (from original series 21 escort cruiser studies) and Study 23 from the later command cruiser studies in the "To a Future Fleet" section. Both seem correct to me.

 

[uk 75]

I still think it is helpful to start with the 1962 CVA 01 drawing from Brown/Moore as posted on the CVA 01 site by Richard B. The configuration of the one or two Seadart launchers at the stern and the Ikara sponson launcher just forward of the deck lift could have been transferred to the 1961 missile aft designs for the Escort Cruiser replacing the aft Seaslug launcher.

By the 1966 drawings the Seadart launcher has moved forward of the superstructure but is not yet mounted forward of the flight deck as on the Invincibles.

There is a gradual evolution at work which we have not all the stages illustrated.

In 1962 the Escort Cruiser design takes on the Ikara system (I imagine in the same sponson mounting as on CVA 01). This is abandoned for CVA 01 and presumably also from the continuing backburner studies which are re-visited in 1966.

The two Seadart launchers on CVA 01 are replaced by a single launcher aft. Again, I assume that the Escort Cruiser design would have followed suit and gone to a one launcher design.

In 1966 studies for a lighter ship to carry Seadart have moved away from the large launcher aft (as on the Type 82) in favour of a launcher forward.

To the best of my knowledge this is all we know at present. However, nowhere is it suggested or described that CVA 01 or the cruiser designs were to have a combined Seadart/Ikara launcher. If such a design exists it would have to date from 1961to 2 and be contemporary to the designs which were the precursor to Type 82 (which keep appearing here).

 

[JFC Fuller]

I tracked down the original source that Brown references for the twin CF.299 and one Ikara escort cruiser design along with a very tiny hint as to its appearance as well as a teasing reference to a sketch drawing and artists impression which I was unable to find (Photos 1 & 2). I also found a reference to a later design with only one CF.299 launcher (Photo 3) as part of a discussion about flying P.1154s of ships other than aircraft carriers.