That's what I was thinking. That and also swept-wing versions of the Gloster G.A.2 Ace, Supermarine Attacker and De Havilland Venom and Sea Venom.
The swept-wing Attacker would be the Supermarine Type 510 built earlier and the swept-wing DH.112 Venom/Sea Venom would be the DH116 proposal brought forward.
For this thread I'd like to go back to 1940.
The POD is that the Air Ministry/Ministry of Aircraft Production awards the contract to build Whittle's engines to Rolls Royce instead of Rover.
This is because I want Rolls Royce to give up developing piston engines to concentrate on gas turbines two years earlier.
I also want this to happen so that there are different Specifications F.1/43 and F.2/43. IOTL they let to the Supermarine Spiteful & Seafang and the Hawker Sea Fury respectively.
ITTL both specifications are for Nene powered fighters with straight wings, effectively the Supermarine Attacker and Hawker Sea Hawk of OTL. The result is that a small number of Attackers are built by Supermarine instead of the OTL small number of Spitefuls and Seafangs, while several hundred Sea Hawks are built for the FAA and export instead of the Sea Furies of OTL.
The next step is for the OTL Specs. E.10/44 and E.1/45 to be for a fully swept version of the Attacker, effectively the Supermarine Type 510. Three prototypes were built instead of the 3 Attacker prototypes of OTL. Next there would be a pre-production batch of 24 aircraft (18 of which would be navalised) built in the late 1940s for trials. It would enter service with the FAA in 1951 instead of the OTL Attacker. If there is still a Swift ITTL its OTL problems would have been sorted out on the 24 pre-production versions of the Nene-powered version built instead of the Attacker.
Meanwhile, a fully-swept Sea Hawk, effectively the P.1083 of OTL, was built by Hawker instead of the OTL Sea Hawk. This would enter service with the FAA in 1953. However, development was rapid enough for a land-based version to enter service with the RAF instead of the Hunter F. Mk 8. This would also be built for the RAF instead of the Meteor F.R. Mk 9, P.R. Mk 10 and the N.F. Mks 11 to 14. I also want it to be built instead of the Meteor T Mk 7, but I'm not sure that there will be enough time for that.
Meanwhile the earlier availability of the 3,500lb/st RR Derwent allows equivalents to the Meteor Mk IV and F. Mk 8 to be introduced 2 years earlier than OTL.
ITTL the earlier entry of Rolls Royce into the centrifugal gas turbine business means that the TTL Gloster GA.1 designed to Spec. E.5/42 ITTL is effectively the GA.2 built to E.1/44 ITTL. Unlike the OTL Gloster E.5/42 the TTL version was built and flown. However, it didn't go into production because the TTL improvements in the Meteor meant that the improvement in performance wasn't big enough to justify this. In common to its rivals from Hawker and Supermarine, the TTL Gloster E.1/44 would be a swept-wing version of the OTL aircraft. However, it still wouldn't fly until 1948 by which time it had been decided that Gloster would build Hawker's fully-swept Nene-powered fighter.
I don't know how to do it, but ITTL swept-wing versions of the Venom and Sea Venom (effectively the later DH.116 proposal of OTL) were built. OTOH the FB Venom didn't enter service until 1952 IOTL the NF version didn't enter service until 1953. Therefore, ITTL the Air Ministry/Ministry of supply might have De Havilland and Fairey build Hawker's swept-wing jet fighter instead, but possibly with the DH Ghost engine instead of the RR Nene.
I've already written that the TTL Supermarine Swift will be a better aircraft because of experience gained with the TTL swept-wing attacker. Hopefully, the TTL Hunter, DH.110 and Gloster Javelin will have fewer problems due to experience that De Havilland, Gloster and Hawker accumulated with the swept-wing Nene powered fighters built ITTL.
Development of the RR engine for the Miles M.52 (not cancelled ITTL) would be ahead of OTL in development, but I don't know if that means an earlier first flight date.
As an aside the RR Clyde turboprop would be a year or two ahead in development IOTL. That might mean that they Clyde-powered Westland Wyvern goes into production ITTL and the proposed Clyde-powered Windsor would fly in prototype form. We might get Clydes on the Airspeed Ambassador, HP Hermes and the HP Hastings. I'd love to see a British Hercules equivalent with Clyde engines built instead of the Blackburn Beverley.
Though what I really want to see with the earlier availability of the Clyde is for Avro to build a Clyde-powered equivalent to the Boeing Superfortress instead of the Lincoln. There would also be a Clyde-powered equivalent to the Boeing KC-97 and Stratocruiser built instead of the Avro Tudor.
However, the downside is that more advanced RR jet engines are sold to the USSR and they build something better than the MiG-15 around it.