Upgrading Royal Navy Type 21 frigates

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The six surviving Type 21 frigates had been worked hard ans I suppose it was time to sell them to Pakistan.
But by replacing the Seacat with a Vulcan Phalanx turret and Exocet by Harpoon the ships could have been given a further lease of life with the RN.
 
I'm not sure the RN was ever happy with these ships. Crews complained I seem to recall.
 
Considering 7 out of 8 T21 were sent to the Falklands, the largest number of any class of ship I am not sure they were so bad.
The only armament weakness was Seacat and a Phalanx turret could have improved that. Four Harpoons could have reduced the weight by replacing the bulky Exocet cannisters.
The T21 served widely in the 70s and 80s and the hulls had to be strengthened. Criticisn of their vulnerability forgets that much of their work was peacetime stuff. We had the T22 for the aggressive work.
 
Risking straying into 'Urban Myth' territory, but....
My understanding of the original concept behind the Type 21 design was an 'in fill' between the over-produced Leander (Mod. Type 12) class, which I think you will find were in production for longer than originally intended and the Type 22 class which were much delayed.
I believe that the original intention was to only build 3 Type 21's, but he delays in the Type 22 programme resulted in an the later numbers to eight vessels.
It was unfortunate that the originally intended one-for-one swop of Sea Wolf for Sea Cat did not happen due to the increase in weight of Sea Wolf. If the twin launcher for Sea Wolf had come to fruition/earlier, then perhaps they would have received at least one, if not two of these...
Vosper-Thornycroft, the commercial designers involved with the Type 21's did propose an slightly enlarged version - extra beam and the installation of Lightweight Sea Wolf and Surface-t0-surface missiles (in that case Exocet's).
All sorts of rumours about the combustibility of Aluminium as opposed to steel also helped to bias the opinion of the design of the original ships - losses during the Falklands Conflict were allegedly blamed on this for one of them.
Also, remember that the Batch 3 Type 42 Destroyers also had to have reinforcing plates added to their hulls, so it was not just the Type 21's that had these fitted.
Gossip has it they were quite popular amongst the younger officers who had them as early commands as they were regarded as quite 'sporty' with their rapid acceleration due to their all gas-turbine power train.
A bit like the older Tribal (Type 81) class frigates, originally classified as 'Sloops' they were seemingly intended for more Cold War/Showing the Flag operations, and I do not think they were intended to have long Royal Navy careers originally.
 
Pirate Pete said:
Link to Post 4.
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That's more or less what I've read. They did what they were intended to do and the aluminium superstructures weren't the fire hazard they were made out to be.

I've put details of some of the proposed developments of Type 21 up on other threads, either here on Alternatehistory.com.

However, I think that upgrading the Type 21 would increase the cost to the extent that it would cost the same as a Type 22 or Type 42. Types 21, 22 Batch 1 and 42 all had the same Olympus-Tyne COGOG machinery. Therefore, on the theory that "steel is cheap and air is free", all the difference in cost must have been the extra weapons and more advanced sensors.

Therefore, a Type 22 Batch 1 or Type 42 "is" an upgraded Type 21. Therefore, one might as well spend the extra money on more Type 22s or 42s. Probably, the latter as they were ordered and built concurrently with the 6 Type 42 Batch 1 ships.
  • The machinery was the same.
  • The 4.5in Mk 8 gun was the same.
  • The torpedo tubes were the same.
  • The helicopter facilities were the same. That is, a hangar and flight deck for one Lynx-size helicopter.
  • The Type 184 sonar was the same.
  • Type 21 had CAAIS and Type 42 Batch 1 ADAWS-4, but both used Ferranti FM1600B computers.
  • Type 21 had 4 Exocet SSM, GWS.24 Sea Cat.
  • Type 42 had no SSMs or Sea Cat, but it did have GWS.30 Sea Dart and a Type 965 AKE-2 radar.
So the major difference between Types 21 and 42 Batch 1 is that the latter had Sea Dart & a Type 965 radar and Type 21 didn't.

Estimated costs according to my copy of Jane's 1969-70 were £7-8 million for a Type 21 and £17 million for a Type 42. My guess is that the Sea Dart system, Type 965 radar and ADAWS accounted for nearly all the difference of £9-10 million.
  • At this stage the armament of Types 21 and 42 didn't include STWS torpedo tubes and therefore wasn't included in the estimated cost. The extra cost of fitting them to both ships would have been exactly the same.
  • At this stage the armament of the Type 21 didn't include Exocet so it wasn't included in the estimated cost. Fitting it would have increased the cost and reduced the difference between its cost and the cost of a Type 22 or a Type 42.
  • And if I remember correctly, the first Type 21s weren't completed with CAAIS. If I have remembered correctly the cost of CAAIS might not have been included in the estimated cost of a Type 21 when Jane's 1969-70 was published.
@Pirate Pete wrote that the number of Type 21s built was increased from 3 to 8, because the Type 22 design wasn't ready. My recollection is somewhat different.

Yes, the Type 21 was built as a stop-gap while the Type 22 was being designed (as the Ship Department didn't have the capacity to design Types 22 and 42 at the same time) but the increase from 3 to 8 ships was because British industry couldn't build more Type 42s, because it couldn't build enough Sea Dart systems.

All 14 ships were ordered during the course of 1968-71.
  • Sheffield was ordered on 14.11.68.
  • Amazon was ordered 4 months later on 26.03.69.
  • Active & Antelope were ordered next on 11.05.70.
  • The 10 remaining ships were all ordered in 1971.
    • Birmingham & Coventry on 21.05.71.
    • Cardiff on 10.06.71.
    • Then Alacrity, Ambuscade, Ardent, Arrow, Avenger, Glasgow & Newcastle were all ordered on 11.11.71.
  • The first Type 22 wasn't ordered until 08.02.74. However, (I think) Jane's 1972-73 said the first ship was to be ordered in 1973. I suspect that the reason for the delay was the UK's economic difficulties rather than the design not being ready.
Inability on the part of British industry to build enough Sea Dart systems feels like a plausible reason to me. According to Freidman (my source about why more Type 21s were ordered) the long building times for the first 6 Type 42s wasn't due to inefficient shipyards, but late deliveries of the weapons & electronics, which in turn was because the British electronics industry was concentrating on its export contracts.

Therefore, my upgraded Type 21 is a Type 42 Batch 1, preferably, the version before Dennis Healey allegedly had it the hull shortened as a cost reduction measure.
 
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So arguably a Type 42 armed with Exocet instead of the Sea Dart System, Type 965, and perhaps keeping ADAWS ought to be competitive with Type 21?
 
The T21 compared favourably with the Leanders in being able to carry Exocet as well as a gun.
I am not sure that Seawolf was a realistic option for these ships as the two missile launcher was too small a number of weapons in one launcher. I think that is why Phalanx or Goalkeeper was fitted on T42 and T22 instead. VL Seawolf was the real solution and arrived with T23.
 
The RN ship accommodation levels merits a thread of its own but given the knowledge of some members here I am happy to broaden the thread as T21 replaced a number of older frigate classes. How did these and the later T22 and T23 compare.
I have been told by a number of ex RN that carriers were not popular berths.
 

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