The RAF, just that little bit better in 1940

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
One of the immediate problems I have with the British having a 'semi official' air group fighting for the Republicans is that Britain was still clinging to the notion of the League of Nations acting as a force to prevent or subdue such wars a league that which they were a major partner - so while yes such a thing would have helped better develop tactics etc going into 1939+ and I would have loved to see it happen (Extra magic fairy dust points for getting George Orwell to become an ace pilot in said unit) - I just cannot see the British government going for it at the time.
 
It occurred to me that in OTL the Brits bought the license to produce a aircraft version of the American M1919 machine gun originally chambered in 30:06 and rechambered their version in British .303. These provided the main armament for pretty much all British fighters in the early war. It occurred to me that it might have been more useful if the Brits had bought the license for the .50 BMG M2 Browning and used that as their fighters main armament until suitable auto cannons were available. They could have also probably been useful in replacing the .50 caliber Vickers used for a variety of purposes. Of course proper auto cannon would be better for a lot of those roles but the M2 Browning was an existing high quality design that the Brits could have bought off the shelf.

Might be a little helpful for the Spitfires and Hurricanes during the BOB.

The Swedish/Belgian 13.2 version of the M2 Browning also intrigues me. It seems like it had real potential but it came out at just the wrong time and didn't have the chance to be widely produced or sold. As it was the German conquest of Belgium disrupted production and export with the Swedes getting the majority of the guns and using it as their main armament for their fighters during WW2. Post war the absurd numbers of surplus .50 BMG M2 Brownings flooding the market killed any possible resurgence in the design. Perhaps if work had begun a little earlier the Brits could have bought a production license and used it as their main early war armament for their Hurricanes and Spitfires.

 
It occurred to me that in OTL the Brits bought the license to produce a aircraft version of the American M1919 machine gun originally chambered in 30:06 and rechambered their version in British .303. These provided the main armament for pretty much all British fighters in the early war. It occurred to me that it might have been more useful if the Brits had bought the license for the .50 BMG M2 Browning and used that as their fighters main armament until suitable auto cannons were available.
The Japanese also bought the M1921 30 Browning.
Unlike the British, they expanded it on their own, to 12.7(not 50 BMG, but Italian) and then to 20mm( a shortened 20mm Hispano round) and up to 30mm by War's end, all using the short recoil system, scaled up.

That was the IJA
Navy went a completely different path for their cannons, of course.
 
The Japanese also bought the M1921 30 Browning.
Unlike the British, they expanded it on their own, to 12.7(not 50 BMG, but Italian) and then to 20mm( a shortened 20mm Hispano round) and up to 30mm by War's end, all using the short recoil system, scaled up.

That was the IJA
Navy went a completely different path for their cannons, of course.
Considering how much the IJA and IJN tried to kill each other it's amazing they had ammo left for ya know fighting the actual war.

Gives me the idea for a story involving a Civil War in Japan in the 30's.
 
It occurred to me that in OTL the Brits bought the license to produce a aircraft version of the American M1919 machine gun originally chambered in 30:06 and rechambered their version in British .303. These provided the main armament for pretty much all British fighters in the early war. It occurred to me that it might have been more useful if the Brits had bought the license for the .50 BMG M2 Browning and used that as their fighters main armament until suitable auto cannons were available. They could have also probably been useful in replacing the .50 caliber Vickers used for a variety of purposes. Of course proper auto cannon would be better for a lot of those roles but the M2 Browning was an existing high quality design that the Brits could have bought off the shelf.

Might be a little helpful for the Spitfires and Hurricanes during the BOB.

The Swedish/Belgian 13.2 version of the M2 Browning also intrigues me. It seems like it had real potential but it came out at just the wrong time and didn't have the chance to be widely produced or sold. As it was the German conquest of Belgium disrupted production and export with the Swedes getting the majority of the guns and using it as their main armament for their fighters during WW2. Post war the absurd numbers of surplus .50 BMG M2 Brownings flooding the market killed any possible resurgence in the design. Perhaps if work had begun a little earlier the Brits could have bought a production license and used it as their main early war armament for their Hurricanes and Spitfires.

At the time of the decision on the next armament for fighters, current fighters where still canvas, and the Lewis and Vickers were all that RAF personal knew.
A single hit from a 20mm cannon was assumed to take a canvas aircraft of the period.
The high speed of newer fighters only gave fractions of a second to fire and achieve hits.
Hence why 8 Brownings or 4 cannon was chosen (but never actually tested against aircraft targets!!)

The real world showed one must hit the pilot, fuel tank, or destroy the engine or main spar to down an aircraft.

Some have suggested a FF 20mm cannon, but it failed against modern / armoured aircraft. 530 Rpm is to slow, 60rds is not enough.
It could not penetrate the armour protecting the pilot and tank from behind, or shatter an engine or main spar.

20mm Hispano requires a new wing for spitfires ("C" wing), which means a break in production when Britain needs fighters, any fighter.
The Hurricane IID is a slug with 4 cannon. Brown is quite uncharitable about this model.
There is limited HE for it, until production starts, especially for fuses. 50% as plain ball until late 41, little better than any other MG ball ammo.

Most pilots are green, and can't hit the side of a barn. They need lots of fire to hit.
There is a huge stock pile of .303 ball, but not AP or Incendiary rounds.

The M2 Browning was ready by 1933 and in production. The problem of the '20s model M21 were solved.
Aircraft were been designed with M2 in the mid -'30s. One of the earliest is the P-36 Hawk, that first flew in 1935.
As said above .50 AP will penetrate 10mm at 1200m, and 19mm at 500m. It easy penetrated aircraft armour way beyond air combat range during BoB.
It would shatter an engine block, etc.

One could have put the M2 into a standard "A" wing, and removed the divider between to two inner .303' ammunition bays for the larger .50" rounds.
M2 weighs 29kg, 9kg heavier than 2 .303' brownings. 150rds .50"' ~ 17kg vs ~17kg of 2 x 350rd .303" ( 18kg difference)
(BTW Hispano is 60kg with 60rd drum, 15.5kg for 20mm 60 rds, or 38.5 kg per side or 77kg heavier!!)

IF the M2 had been dropped in, the production of .303" AP and incendiary would not be required, and production focused on the more effective .50" versions.
As these are pressed filled, fuseless, they are cheaper and easier to mass produce.

Lastly there was a shortage of .303" Brownings at the start of the war, as production could not keep up with aircraft.
Fighter were fitted with only 4 early on. Buying US M2 could have solved this problem.
Later production .303" Browning could have being fitted with heavy barrels and used by Royal Armoured Corps.
No need for BESA and 7.92mm. BESA production should have gone to M2 and .50".
 
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At the time of the decision on the next armament for fighters, current fighters where still canvas, and the Lewis and Vickers were all that RAF personal knew.
A single hit from a 20mm cannon was assumed to take a canvas aircraft of the period.
The high speed of newer fighters only gave fractions of a second to fire and achieve hits.
Hence why 8 Brownings or 4 cannon was chosen (but never actually tested against aircraft targets!!)

The real world showed one must hit the pilot, fuel tank, or destroy the engine or main spar to down an aircraft.

Some have suggested a FF 20mm cannon, but it failed against modern / armoured aircraft. 530 Rpm is to slow, 60rds is not enough.
It could not penetrate the armour protecting the pilot and tank from behind, or shatter an engine or main spar.

20mm Hispano requires a new wing for spitfires ("C" wing), which means a break in production when Britain needs fighters, any fighter.
The Hurricane IID is a slug with 4 cannon. Brown is quite uncharitable about this model.
There is limited HE for it, until production starts, especially for fuses. 50% as plain ball until late 41, little better than any other MG ball ammo.

Most pilots are green, and can't hit the side of a barn. They need lots of fire to hit.
There is a huge stock pile of .303 ball, but not AP or Incendiary rounds.

The M2 Browning was ready by 1933 and in production. The problem of the '20s model M21 were solved.
Aircraft were been designed with M2 in the mid -'30s. One of the earliest is the P-36 Hawk, that first flew in 1935.
As said above .50 AP will penetrate 10mm at 1200m, and 19mm at 500m. It easy penetrated aircraft armour way beyond air combat range during BoB.
It would shatter an engine block, etc.

One could have put the M2 into a standard "A" wing, and removed the divider between to two inner .303' ammunition bays for the larger .50" rounds.
M2 weighs 29kg, 9kg heavier than 2 .303' brownings. 150rds .50"' ~ 17kg vs ~17kg of 2 x 350rd .303" ( 18kg difference)
(BTW Hispano is 60kg with 60rd drum, 15.5kg for 20mm 60 rds, or 38.5 kg per side or 77kg heavier!!)

IF the M2 had been dropped in, the production of .303" AP and incendiary would not be required, and production focused on the more effective .50" versions.
As these are pressed filled, fuseless, they are cheaper and easier to mass produce.

Lastly there was a shortage of .303" Brownings at the start of the war, as production could not keep up with aircraft.
Fighter were fitted with only 4 early on. Buying US M2 could have solved this problem.
Later production .303" Browning could have being fitted with heavy barrels and used by Royal Armoured Corps.
No need for BESA and 7.92mm. BESA production should have gone to M2 and .50".
The RAF Browning 0.303" had significant differences to a vehicle mounted one. Closed bolt, lightweight barrel as just two of them. The BESA was a straight licenced copy of a vehicle mounted gun so no changes necessary and low risk. The ammunition was no real problem. 7.92mm was being made in Britain anyway and it came up with the 2 pounder ammunition and POL separately from infantry supply lines.

The RAF looked at 0.500" guns, US, British and Belgian but concluded that they weighed little less than 20mm cannon and were more effective so chose to jump the 0.500" stage. The USA also was looking towards a cannon standard even if they cocked it up. The French, German and Soviets were also looking towards a cannon standard so the RAF decision was in line with world practice. They just had never bothered with the 0.500" already. 'Rivet counters' will advise of the detail but the early/mid 1930s Browning 0.500" rate of fire I understand put a lesser weight of fire, for a given weight of gun and ammunition, for the expected very short firing time at period speeds. Bombers were not then armoured so a large battery of 0.303" was a very reasonable choice and seemed to be able to cope until the RAF got the cannon standard and those cannon were intended for larger new fighters than the new interceptor single seaters. In the event the 20mm had to go in what was in production and initially with drums to work. Had they gone to a 0.500" standard (ideally as in the Belgian 13.2mm type form) they would still have been working towards the cannon standard anyway. At the time it made sense to skip the intermediate stage. Whatever the cannon in the early war Spitfire and Hurricane may have done to their performances the RAF chose to put the cannon in for a perceived advantage. After all they had the 12 gun 0.303 "option as used on the Hurricane and Typhoon.

The RAF and FAA did import 0.500" Brownings and fit them in various cases (e.g. Spitfire and Fulmar) so there was no actual prejudice against them. Merely that the 20mm cannon was reasoned to be the superior option at the time. The RAF was well aware of the world's available heavy machine gun designs and the weaknesses of their Lewis and Vickers in service.
 
The RAF and FAA did import 0.500" Brownings and fit them in various cases (e.g. Spitfire and Fulmar) so there was no actual prejudice against them. Merely that the 20mm cannon was reasoned to be the superior option at the time. The RAF was well aware of the world's available heavy machine gun designs and the weaknesses of their Lewis and Vickers in service.
I agree about the superiority of the 20mm. My reasoning according to the criteria set forth in the OP was how to make the Spitfire and Hurricane better fighters in time for the BoB. Without the 20mm being ready in 1940 I think the .50 HMG would have served as an improvement over the .303 and as a stop gap between the .303 and the 20mm. If there was any possibility of getting improved belt fed 20mm cannons in the wings of the RAF fighters by the Summer of 1940 that would have been far better then the .303s they had to make do with.
 
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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)
I didn't think about the trainer and tug market. That said it's a lot of development work for what is essentially a second tier market compared to fighters and bombers.
 
The RAF Browning 0.303" had significant differences to a vehicle mounted one. Closed bolt, lightweight barrel as just two of them. The BESA was a straight licenced copy of a vehicle mounted gun so no changes necessary and low risk. The ammunition was no real problem. 7.92mm was being made in Britain anyway and it came up with the 2 pounder ammunition and POL separately from infantry supply lines.

The RAF looked at 0.500" guns, US, British and Belgian but concluded that they weighed little less than 20mm cannon and were more effective so chose to jump the 0.500" stage. The USA also was looking towards a cannon standard even if they cocked it up. The French, German and Soviets were also looking towards a cannon standard so the RAF decision was in line with world practice. They just had never bothered with the 0.500" already. 'Rivet counters' will advise of the detail but the early/mid 1930s Browning 0.500" rate of fire I understand put a lesser weight of fire, for a given weight of gun and ammunition, for the expected very short firing time at period speeds. Bombers were not then armoured so a large battery of 0.303" was a very reasonable choice and seemed to be able to cope until the RAF got the cannon standard and those cannon were intended for larger new fighters than the new interceptor single seaters. In the event the 20mm had to go in what was in production and initially with drums to work. Had they gone to a 0.500" standard (ideally as in the Belgian 13.2mm type form) they would still have been working towards the cannon standard anyway. At the time it made sense to skip the intermediate stage. Whatever the cannon in the early war Spitfire and Hurricane may have done to their performances the RAF chose to put the cannon in for a perceived advantage. After all they had the 12 gun 0.303 "option as used on the Hurricane and Typhoon.

The RAF and FAA did import 0.500" Brownings and fit them in various cases (e.g. Spitfire and Fulmar) so there was no actual prejudice against them. Merely that the 20mm cannon was reasoned to be the superior option at the time. The RAF was well aware of the world's available heavy machine gun designs and the weaknesses of their Lewis and Vickers in service.
Considering the large stockpile of .303”, introducing a new caliber is crazy.

The brits introduced BESA as a replacement for all vickers, not just RAC. It wanted to convert BESA to .303” but it would have been a nightmare with a rimmed cartridge. It only introduced a new gun / round after been realising the facts of old stockpiles of .303” and vickers.

Putting a heavy barrel in the browning and slowing rate of fire, has already been done in the M1919 Browning. Later model L3 A2/3 models were open bolt!

It can handle rimmed .303” and yes is open bolt. Much better the standard M1919 supplied with US made tanks, which induced another caliber to UK forces around the world.

As to BoB aircraft, yes nations were going to 20mm, but at this stage engine power didn’t allow it (vs current Me109), and RCMG took 1,000s to stop bombers. The M2 was Ready.
 
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The BESA noted the delays and costs of converting the ZB26 design to 0.303" BREN and imperial standards so went the simple fast route of making the BESA as designed in metric and 7.92mm. There was a consideration of changing the whole small arms suite to 7.92mm, hence the SLEM semi automatic rifle in 7.92mm so the BESA would allow Vickers production to be free of RAC needs and be prepared with a 7.92mm Vickers cheaper and easier to make replacement. The Vickers was good but expensive to make.

FWIW at one time they looked at the 15mm BESA as a back up to the 20mm Hispano. Especially as US made Hispanos were unusable. But this is post BoB.

Hawkers were well aware of the 13.2 FN Browning installation designs for the Belgian production Hurricanes. If the followed the same timescale as Fairey S.A. in Belgium, with both the gun production (which would have to be in lieu of some OTL 0.303" production which was already behind demand) and the wing changes, then the 4x13.2mm armament could have made it to Hurricanes in time for the BoF and BoB but it might prevent Hispano production to keep 0.303 Browning production up and delay or prevent the improvement to 20mm cannon post BoB.
 
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.
That will still mean that we're trying to improve the 3rd best fighter that RAF have had in service in 1940. Perhaps it will be better use of money, production lines, manpower and training (turret fighter will need twice the crew vs. Hurri & Spit) to make more of best and second best fighters.

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.
By 1938, people knew better indeed. Some countries evan have had monoplane fighters and bombers in service by early 1935 - what a blasphemy.
At 16000+ ft and aerodynamics of the day (late 1930s), a 1000+ HP V12 engine buys you 350-370 mph fighter that can carry twice the number of guns. 350-370 mp means one can catch not just current bombers that can do 250-280 mph, but also offers a performance cushion against the possible future bombers that can do 300+ mph (as done in 1940 by DB7s and bombed-up Bf 110s) and recons.
It can also carry cannons, that Defiant is ill suited to carry. Head-on attack, or beam attack perhaps? Classic fighter is far better in this. Attack from dive? Again classic fighter is better. Need to climb well? Classic fighter again, there is no turret to add the weight and drag. Turret also adds to the production time and expense.
 
That will still mean that we're trying to improve the 3rd best fighter that RAF have had in service in 1940. Perhaps it will be better use of money, production lines, manpower and training (turret fighter will need twice the crew vs. Hurri & Spit) to make more of best and second best fighters.
Quite so but my comment was in the light of the OP 'just that little bit better' and it would take little extra to optimise the Defiant as it was IOTL.
 
Quite so but my comment was in the light of the OP 'just that little bit better' and it would take little extra to optimise the Defiant as it was IOTL.
Okay, roger that.
Perhaps it would've been the best to have Defiants produced as plain-vanilla fighters with eight .303s? Should be comparable with Hurricane performance-wise?
 
Okay, roger that.
Perhaps it would've been the best to have Defiants produced as plain-vanilla fighters with eight .303s? Should be comparable with Hurricane performance-wise?
Better still use the Resource and cost footprint to build an actual Hurricane or Spitfire instead!
 
So I was reading through my Osprey - Defiant, Blenheim, and Havoc Aces book and it is interesting that there was one Defiant squadron (No. 264) that did rather well. It seems the squadron commander (Squadron Leader Phillip Hunter) was a true believer in the turreted fighter and he worked hard to develop tactics to maximize the weapon system's capabilities. The squadron actually produced nine aces but Hunter's death on 24 August 1940 saw the demise of the fighter's biggest advocate and that was the end of that.
 
For all the criticism it receives the Defiant was a reasonably effective night fighter at a time when it was desperately needed, if you're not going to build it you need to build something else to replace it. There aren't exactly a lot of choices for two seat single engine fighters at the time, and the Defiant out performed the Fulmar which is the obvious alternative. You could say build more Beaufighters, but that takes twice the resources as a single engine fighter.
 

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Is there a better option to the Lysander? Certainly, not a first, or even second priority, but since nearly 1800 were eventually built; was it the best use of the production facilities?
 
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