Shipbucket

Study 21


Study 22


Study 23

The Command Cruiser of 1968 would become the Invincible Class CVLs of the 1970s, but had its origins of the Escort Cruiser developed off and on from 1959.

The history of the Escort Cruiser is quite complicated to reproduce here, various studies were made from 1959, then 1960-61 with Sea Slug and 4.5in guns (Shiplover drew one of the Series 9 and Series 21 designs years ago and they can be found in the Archive). In 1962 the designs included the Chinook, which was to be procured as an ASW helicopter and fitted for two launchers for Sea Dart and fitted with Ikara (debate rages regarding whether a common launcher for both was to be used) and capacity for 700 troops. Very little is known of these ships and no sketch designs have been found so far. The construction of the Polaris Fleet deferred construction, then it was decided to convert the Tiger Class instead as a cheaper stopgap and finally the CVA-01 programme was cancelled, killing their rationale.

In early 1966 the Future Fleet Working Party was formed and they studied an escort cruiser/commando ship, later becoming a commando cruiser. In June 1966 discussions saw six ships planned, the first to commission in May 1975. Studies were made of superstructure forward, superstructure aft and a conventional carrier layout. The latter being finally selected. Sea King would be carried along with the Kestrel V/STOL fighter, weapons included Sea Dart and PX430 (Sea Wolf) and a Type 988 3-D radar would be fitted. By August 1966 the designs were growing to 16,000 tons and costs to £31.5 million. The recommendations issued that month included four cruiser carrier studies, three cruiser studies and a commando ship. The combined cruiser commando ship was rejected and a maximum displacement of 10,000 tons was desired. Kestrel was cut and a call to raise the size to 13,000 tons was never agreed. The Treasury were supportive and six ships were still planned, the first to commission at the end of 1975.

In December 1967 Naval Staff Target NST 7097 was raised to cover the ship. In January 1968 the DNC proposed the three designs above.

Study 21 was a conventional cruiser design with aft flight deck, displacement 12,750 tons deep. The superstructure had a hangar for six Sea Kings. Armament was Sea Dart (22 missiles minimum) and 2x1 20mm [the plan in Brown & Moore seems to indicate a triple A/S torpedo mount, I'm not sure if this correct, but seeing as Type 42 had them and this is more a destroyer than a carrier in style, I've kept them]. Gas turbines would drive the ship to 28kts, dimensions were 550x72ft. Complement would be 959, cost within £30 million.

Study 22 was a conventional carrier design with through deck and a hull hangar for nine Sea Kings. Displacement 17,500 tons deep. Armament as above, fitted with steam turbines for 26.5kts, dimensions 595x78ft. Complement 1,068 and cost within £35 million.

Study 23 had the new planned FBNW bottom-bounce sonar and was otherwise identical to Type 22 apart from displacing 18,700 tons deep and having a beam of 82ft. As you might note on the drawings, the island was slightly smaller and some minor changes were made forward. Cost would be £36 million.

Study 22 was selected for final work and the sketch was completed by the end of 1970 and refined over the following 18 months and 5 million man hours were spent on design work. The ship became the Command Cruiser (CCH). Gas turbines selected for propulsion and the first ship, Invincible was ordered from Vickers, Barrow in 1972. For what came next, please see Bombhead's excellent Invincible Class drawings in his carriers thread.

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Hood's Worklist
English Electric Canberra FD
Interwar RN Capital Ships
Super-Darings
Never-Were British Aircraft

Very interesting, you can clearly see the process of evolution that led to the invincible class. Very nice drawings

indeed very nice drawings and informative post. Are you planning topviews of these? such would propably cover more of the shape of these things.

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Shipbucket mainsite, aka "The Archive"
New AU project "Aravala"

Very well done, James.
One small note, is where are the rudders for the cruiser study 22 and study 23?

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Thank you Kim for the crest

"Never fear to try on something new. Remember that the Titanic was built by professionals, and the Ark by an amateur"

Great drawings and informative text. Another lovely set of pixel art depicting the evolution of more famous ships.

Very interesting! When reading about CVA-01 I saw mentions about "Invincible-to-be" escort cruisers, and was wondering about some more details about them and their evolution.

And I join Novice's concern about rudders on some of them.

Very interesting and nice to see your 1960s Command Cruiser. i like Study 21 because 342 torpedo, and have plan for MM-38 exocet or other SSM ??

Nice work!

The flightdeck forwards follows the curved lines of the bows. The three Sea Kings on deck are parked on the three marked landing spots.

There were no plans for Exocet at this stage, would have been slightly too early to think about that weapon. These designs are not the same ships as considered for the CVA-01 escort. No-one is exactly sure what those ships would have looked like. Probably closer to Study 21 and Type 82, but on-one knows for sure.

You may have noticed these carry an extra radar (by the 909 domes), I'm really not sure what this radar was. I can't find it on any other ship as built or planned at this date. It looks like a height-finder type set, but its not the old 277/278. I've copied the radar from the plan drawing assuming it to be an additional part of the Sea Dart system. It's not a landing radar as its mounted forward on the Study 21.

Drat, I forgot the rudders! My excuse is that's because they are missing off the plan drawing I was working from. I need to decide if these would have a single or twin rudder (as the Invincible have).
Double drat, just spotted a white eraser tool block on one of the drawings too!

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Hood's Worklist
English Electric Canberra FD
Interwar RN Capital Ships
Super-Darings
Never-Were British Aircraft

very interesting