The RAF, just that little bit better in 1940

Had the 12Y been in production in Britain instead of Rolls trying to reinvent the wheel with the Peregrine then the Gloster Reaper would have been more likely to enter service instead of the Beaufighter,
It might be the Beaufighter anyway.

Admittedly, the G.39 did fly a few months earlier than the Beaufighter IOTL.

However, Gloster's factory re-tooled to build Hurricanes in 1939. It would build 2,750 of them between November 1939 and March 1942. 1,211 of them were built in 1940. Gloster also delivered the first of 3,300 Typhoons in December 1941. It would have re-tooled a year earlier, but the Ministry of Aircraft Production decided that it was better to keep the Hurricane in production for longer.

Meanwhile, Bristol delivered its last Blenheim in January 1940. The first batch of 78 Beauforts was delivered between April 1939 and March 1940. The first 150 Beaufighters were delivered between April 1940 and March 1941. AIUI the Beaufort and Beaufighter could be built on the same production line, which AIUI allowed Bristol to complete the first contract for 150 aircraft sooner than an all-new aircraft.

Therefore, I think that they'll still build the Beaufighter because it doesn't disrupt Hurricane production at a crucial time. Putting the Reaper into production in 1940 would disrupt Hurricane production at a crucial time.
 
It's more a direct follow up of the kestral (21 and 22 litre).

The Kestrel had run the end of its development potential but the developers saw a lot of small changes they could do that would make it a better engine at a similar size.

Also they felt that the Merlin was a little large for a fighter (they didn't realise how fast speed improvement was needed at the time).
Was the failure of the Peregrine and for that matter the Vulture inevitable? AIUI all of the earlier engines produced by Rolls Royce worked. Why did their engineers screw up them up so badly?
 
The failure of the Vulture was probably inevitable, I can't think of a doubled up piston engine that actually worked. I don't think there was anything fundamentally wrong with the Peregrine, there were just other priorities to an engine that was a technological dead end. The day of the 800 - 1000hp engine were coming to end before it was fit to fly, which is a shame as it would have made the Miles Master something of a wonder.
 
The failure of the Vulture was probably inevitable, I can't think of a doubled up piston engine that actually worked.
Almost all the 'X' engines, regardless of which nation developed them, had similar problems with cooling and putting so many cylinders through a common crankshaft leading to big end/conrod failures.

The exception I can think of is the R-R Exe, which was a bit different and so worked. It was Sleeve Valve so had a different internal arrangement, one which avoided the big end/conrod problems on a conventional 'X', and it was air cooled where all the others were liquid cooled which avoided those problems. Sadly it was a bit small, only 22L, but it could reliably do 1200hp and 1,500hp was seen as doable before it was sacrificed on the Altar of Merlin development in 1940. There was an enlarged 46L version, the Pennine, which got developed during the war and was bench tested to 2,800hp, but it never got flown as everyone could see jets were coming.

So if you cancel Vulture because the layout is not worth the effort, then tell R-R to drop Exe and go straight for Pennine and give it RAF priority (Exe was intended for the FAA so was not pushed particularly hard) maybe you can get somewhere.
 
So if you cancel Vulture because the layout is not worth the effort, then tell R-R to drop Exe and go straight for Pennine and give it RAF priority (Exe was intended for the FAA so was not pushed particularly hard) maybe you can get somewhere.
Could they be started a stage earlier than that? I.e. start the Exe instead of the Peregrine (AFAIK the latter was started a few years before the former). Then instead of cancelling the Vulture and starting the Pennine do the the Pennine to begin with.
 
Could they be started a stage earlier than that? I.e. start the Exe instead of the Peregrine (AFAIK the latter was started a few years before the former). Then instead of cancelling the Vulture and starting the Pennine do the the Pennine to begin with.
The Peregrine was a rationalised and improved Kestrel (better metallurgy for higher pressures, better supercharger) so it was seen as 'cheap' as there was an existing design to work of. Hence why Vulture was also seen as 'cheap' because of all the work going into Peregrine. All this was '31/'32 and was carried out alongside upgrades to Kestrel due to all the commonality.

Exe comes about because the Fleet Air Arm want a 1000hp air cooled engine and Rolls Royce have the bona-fide genius Arthur Rowledge recovering from a bout of illness and looking for work that isn't 'main programme' so is a bit less stressful. (And I suspect Rowledge fancied a change from liquid cooled V engines having done Condor, Kestrel, 'R' and early Merlin). To bring it forward you need the FAA to issue an engine spec earlier as that's the motivation to start work on something so outside normal R-R practice.

How on earth you achieve that, without a major restructure of the RAF/FAA, I'm not sure. Maybe if you get someone to do the checks on modern TDS vs the standard British air launched 18" torpedo, they realise something larger will be required and so the FAA bump up the required engine power on Exe (to say 1,500hp) to allow the next-generation of TSR planes to use 21" torpedoes (same size as rest of the RN)?
 
1. Get cannons in the Spitfire and Hurricane as soon as possible.

2. Get the Peregrine sorted and have the Whirlwind in service by 1939.

3. Give the Defiant a couple of forward firing guns. Just enough to put any smart-ass 109 pilot off his stroke.

4. Have RAF planners consider that enemy bombers might just have a fighter escort after all.

5. Send Leigh Mallory to, well, anywhere but 12 Grp, and certainly nowhere near fighters. And while we're at it get somebody to tell Bader to wind his neck in during 1940.

6. Establish the Empire Training Schools much earlier to get a supply of pilots starting sooner.

7. Learn from Spain. The Germans did.

8. And, finally, have somebody in the Air Ministry during the early 1930s to have a look at a patent with the name Whittle on it and say, "You know, I think this lad may be on to something here. Can we sort out some funds?"
 
2. Get the Peregrine sorted and have the Whirlwind in service by 1939.
Do you feel the Peregrine would have found use in other planes other than the Whirlwind?

If so which planes and roles would have suited.

Personally I feel that outside niche roles it wont find major use.

I would compare it to the Bristol Taursus in terms of size and potential which was a rarely enough used plane.
 
5. Send Leigh Mallory to, well, anywhere but 12 Grp, and certainly nowhere near fighters. And while we're at it get somebody to tell Bader to wind his neck in during 1940.
Put Leigh Mallory in command of Army Co Operation Command in 1937-8, give him some decent aircraft to work with and let him get on with what he was good at. Close Air Support for the troops. He was the RAF's expert at it, but because it was seen as a career dead end wangled his way into Fighter Command.
 
Do you feel the Peregrine would have found use in other planes other than the Whirlwind?

If so which planes and roles would have suited.

Personally I feel that outside niche roles it wont find major use.

I would compare it to the Bristol Taursus in terms of size and potential which was a rarely enough used plane.
The Peregrine would have been used in the Miles Master trainer when the supply of Kestrels ran out. It would also have been used on the Master based Martinet target tug and probably the Miles M20 (which may have just been the OTL M24 Master fighter conversion with a Peregrine engine rather than the OTL aircraft)
 
Get the Hispano cannon ordered as soon as the finances were arranged, rather than allowing the Treasury et all to procrastinate and while your about it get the belt feed sorted as well.
Get Sir Hugh Dowding to accept prewar that Filtering at group level would speed up plotting and interceptions,
 
I'm not convinced about using the 12Y.
The French couldn't get them properly into production - one of the issues with French aircraft was the shortage of engines - and apparently they weren't reliable. Possible because they sacrificed eight for reliability.
Now RR being able to solve these problems would be interesting, but I think French pride and independence would have made this impossible before the war.
Its interesting to note that the French in 39 were looking a building the Merlin under license for their aircraft, I doubt they would have considered that lightly
 
What Astrodragon said.

Merlin 2 was good for 1030 HP at 16250 ft, the HS 12Y of the same vintage was making ~700 HP there. On 100 oct fuel, HS 12Y versions of 1940 were making 1000 HP, vs. Merlin doing 1300.

Defiant in a fighter guise was a waste of good engines, the interwar planers forgot that Germany captured Belgium 20 years ago, so there is a place for them to base their fighters close to East Anglia. Any bets that new Germany will not capture the Netherlands, too? Or north of France?
Even without that, how does one catches a 300 mph bomber with a 300 mph fighter?
 
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Merlin 2 was good for 1030 HP at 16250 ft, the HS 12Y of the same vintage was making ~700 HP there. On 100 oct fuel, HS 12Y versions of 1940 were making 1000 HP, vs. Merlin doing 1300.
and at Sea Level?
Like the Allison, needed more than it's supercharger section could provide above 15,000
The Soviets were able to get the RPMs up on their version of that motor on higher octane fuel, so I don't see the design being the limitation. Just needed more development
 
how does one catches a 300 mph bomber with a 300 mph fighter?
If the 300 mph bomber has to fly at 300 mph to match the 300 mph fighter it is flying at way over it's cruising speed so it's range is appreciably reduced so is a form of mission kill. Not the best counter to the 300 mph bomber but still reducing it's effectiveness. BTW (and I will not join in a 'rivet counting' war) the fastest BoB bomber would only do @280 mph clean and noticeably less with a full external bomb load so we would be matching a 300 mph fighter to a (say) 260 mph bomber. The Turret Fighter' was flawed but more could have been done with the Defiant as a turret fighter to make it better with little cost or difficulty.
 
and at Sea Level?
Like the Allison, needed more than it's supercharger section could provide above 15,000
The Soviets were able to get the RPMs up on their version of that motor on higher octane fuel, so I don't see the design being the limitation. Just needed more development
At SL, 880 HP Merlin II, 840 HP for the HS-12s of the same vintage.
Yes, the supercharger needed improvement, it was done by 3rd party, and it still was not as good as old Merlin models.
Soviets reinforced the block by reducing the bore, designed the valve gear for 3 valves per cyl, designed a 2-speed S/C drive and a decent S/C. The redulting M-105 also gained 100 kg, amnd later another150 kg - still was a worse engine than earlier Merlin XII, XX, and even worse than much earlier Merlin X.
 
Even without that, how does one catches a 300 mph bomber with a 300 mph fighter?
The specification the Defiant came from was issued in 1935 - the Type 142 (which became the Blenheim) was considered a marvel in the same year because it could do 307mph and by the time they added armour, guns and all the equipment a bomber needed it was below 270mph. Stick a couple of thousand pounds of bombs in it and it's lower still and if they stay at max speed for the whole flight they'll be using so much fuel they'll probably struggle to do a lap of their own airfield before they needed to land and refuel.

When it was conceived there were no bombers that could 300mph. There were no fighters that could do 300mph. The RAF's front line fighter was the Bristol Bulldog that had a maximum speed of 197mph. The pace of aviation advancement in the late 1930s is truly remarkable - the RAF went from the Bristol Bulldog to the Spitfire in three years.
 
7. Learn from Spain. The Germans did.
I've always thought there was a good POD in there for a better UK performance 1939-41. What if some Sir Humphrey in the War Ministry had the notion of attempting to use the International Brigade (British Battalion) as a laboratory for weapons and tactics. Full deniability etc as a given, but get a cadre of troops from all arms to volunteer (having acquired/stolen) British kit. Likewise I think there were some pilots volunteered, so if the (unhappy recently dishonourably discharged) RAF provided a squadron's worth, even if they were using the Russian/French stuff it would allowed at least someone in 1939 to have (hopefully) learned some of the lessons of WW1 that had been forgotten again: finger four formation, beware the hun in the sun, bombers with escorts etc.
Obviously not all the lessons of Spain are applicable, but as @Martin the Martian said, the Germans did learn some.
Allan
 
It's interesting to note that the French in '39 were looking a building the Merlin under license for their aircraft, I doubt they would have considered that lightly.
Even there they buggered things up, the attempted production was something of a fiasco.
 
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