Advanced French Fighters vs 1942/1943 contemporaries (6 Viewers)

[Shortround6]

A lot of stuff here.

I see what you are getting at here regarding larger is better, but this is a big issue and I don't think i actually agree with it. The US is in fact the stand-out when it comes to very large aircraft.

To some extent this is true. Although the British tended to use large airplanes. Lighter but large.

Most other nations making significant aircraft designs during WW2 - the Japanese, Germans, Soviets, and Italians, made smaller aircraft. And I think there are good reasons for that.

Japanese also tended to larger aircraft than the Germans, soviets and Italians. Japanese held the weight down but they used larger wings/airframes than the other, in general.
Good reasons are they had lower powered engines than the Americans (and British) did.

This is one reason why the bigger is better mindset took hold in the US and to a lesser extent in the UK.

In part the US, British and Japanese were operating over larger areas of the world. Easy to use small aircraft when you only need to fly 100-200 miles.

I'll note that up above, you say Bf 109 peaked in 1941-42, then you say the F model doesn't have enough armament. Maybe those two concepts don't mesh so well...?

109F peaked in 1941-42 at 6,393 lbs (clean?) and a 1350hp T-O (1300hp at 5000meters) engine at about 388-390mph. Yes the armament was light. The G-s did not handle as well, due to the roughly 440lbs increase in weight (with the same armament) and the G-6s got another 100lbs in weight (better armament). Different models of the Gs got lumps and bumps to handle larger wheels/tyres to handle the increased weight (or under fuselage loads). The Gs added enough lumps and bumps that they were not much different in speed despite shifting the DB 605 engine. G's also started fitting Nitrous or water methanol injection for more power although at different altitudes.
109s with short range worked for the Germans but barely. Fighting on the defense means you can use smaller, shorter range planes.
The 109Fs with the 20mm gun had nearly as much firepower as the E-4s, and it lasted several seconds longer. It wasn't really good enough, but it was the backward step some think. (the 15mm gun was).

The Arsenal VG 33 was already in production, with 160 near completion at the time of the armistice.

I love the near completion at the time of the armistice. They had 12 that were flyable (?). The rest were in various stages of completion. They were also running out wood. A real strategic blunder. France did not grow the type of spruce wood needed for aircraft (or had logged most of it in WW I). The Spruce all had to be imported and only about 1/2 of the original purchase passed inspection. Turns out that good aircraft grade spruce wood is a strategic material and not an easy end run around aluminum shortages.
Let's not forget that 151 sq ft wing. At a gross weight of 5856lbs (max gross was 6,393lbs) that is about 38.8lb/sq/ft. A P-40 has to weigh 9,157lbs to get a wing loading that high.

VG 39 was tested with a 1,184 hp 12Y-89ter. The prototype flew with this engine on 15 June 1940, reaching speeds of 388 mph.

And how much does the 12Y-89ter engine weigh? does it need a larger propeller?
AND it is a prototype!
First Corsair flight was on 29 May 1940 and the prototype soon exceeded 400mph. First combat was Dec 1942.
First Typhoon flight was 24 February 1940. Typhoon was still a near disaster in the summer of 1942.
English accounts of many of the French prototypes ae not good. Perhaps based on estimates or unrealistic expectations (or misprints).
D551 weights seem to be off. Difference between empty weight and gross weight does not allow for much fuel, or an adult pilot or much (any?) ammo. Something is off.
MB 157 grew over 10% in wing area. Also some accounts give engine power that was never achieved in 4-6 years of post war work. Protype never had guns fitted. Speed may be from a cross-country flight with a strong tail wind?

 

[Steamed_Banana]

Japanese fighters were quite small, both A6M and Ki-43 were small aircraft even though they had big wings, much smaller than say, a Hurricane, an F2A Buffalo or a Typhoon. Positively miniscule next to a P-47, but then again, what isn't. Fuselage of a Ki-43 is a bit smaller than a Spitfire, comparable to a Yak 1. Wings are a little wider in span but not very thick and yes, as we know, not heavy at all.

Corsair, which was a totally new design, isn't an apt comparison to an improved version of an existing type ala D.520 or VG.33 derivations. Same for the Typhoon.

Even if the speed on that Bloch test is off (it wouldn't surprise me) it's a cinch that they had it up to competitive levels for 1940-41, i.e. ~350 mph or better. Probably a good bit better.

 

[Shortround6]

Japanese fighters were quite small, both A6M and Ki-43 were small aircraft even though they had big wings, much smaller than say, a Hurricane, an F2A Buffalo or a Typhoon.

OK, let's see.
Plane...............................Sq/ft of wing
A6M2....................................241.5
A6M3....................................231.7
Ki-43 I...................................236.8
Ki-43 II..................................230.4
Hurricane.............................257
Spitfire..................................242
Typhoon..............................279
F2A Buffalo........................208.9
P-39......................................213
P-40......................................236
Ki-84.....................................226
N1K1-J.................................257
F4F-4....................................260
Just about all of the French, Italian and Soviet fighters were under 200 sq ft or just over.
F2A was fat, but it was short. around 3 feet shorter than some of the other planes.
Typhoon was one of the first single engine single seat fighters to be around 11,000lbs.
Hawker didn't advance the state of art in flap design much over the Hurricane.
Every designer in every country used the size wing he thought needed to meet the requirements. Maneuverability, Field performance, storage for guns/ammo or fuel, Landing gear.
XP-39 needed to hide 200 US gallons (757liters) in the wings, no fuel in the fuselage. Then came the requirement for self-sealing tanks and 80 gallons went away while they kept the existing wing (or at least it's shape).

Corsair, which was a totally new design, isn't an apt comparison to an improved version of an existing type ala D.520 or VG.33 derivations. Same for the Typhoon.

It is not as bad as you think. Typhoon had a lot of trouble with engines. They tried 3 different ones. F4U saw a lot of changes, but the engine was not trouble free either. The basic engine was OK. The two stage supercharger gave some trouble.
Problem I have with the French wonder planes is they need extensively modified engines in existing airframes. Air frames maybe fine (or not, the D 551 is suspect, for one) but the higher powered Hispano engines are a real quagmire. basically take 900-1000hp engine. Slap new cylinder heads on it (more valves), increase the boost, increase the rpm, and expect and engine that had trouble lasting 100 hours at the lower power levels to be just fine at higher power levels.
Or expect the GR 14R to be a somewhat trouble free engine in 1940-41 when they had little run time on the bench in 1940-41. About all the 14R kept from the 14N was the bore and stroke. New crankcase, new crankshaft, new rods, new pistons, new cylinders, new cylinder heads and list goes on.

Even if the speed on that Bloch test is off (it wouldn't surprise me) it's a cinch that they had it up to competitive levels for 1940-41, i.e. ~350 mph or better. Probably a good bit better.

Any time, I repeat, ANY TIME, I see reports of amazing performance of both speed and climb in a single test, especially the first test flight, the bullshit meter pins it's needle to the side of the gauge. The Bloch 157 didn't even fly until 1942.
Bloch 157 may have been a fine airplane but the engine is a real problem. The article linked to
Bloch MB.157
seems to claim that a turbo-compressor in two-stages was used. Other sources may say this but it is the only time I have seen it. Photos show no evidence of a turbo-compressor.
No description of the engine itself mentions a turbo compressor. Even several post war accounts.
The engine itself in two speed form, is supposed to give as much power as the identical displacement (same bore and stroke) as mid WW II Hercules engines at higher altitudes while turning 200-300rpm slower and using close the same boost and using lower compression in the cylinders.
"If you believe that you will believe anything." Duke of York.

 

[Steamed_Banana]

OK, let's see.
Plane...............................Sq/ft of wing
A6M2....................................241.5
A6M3....................................231.7
Ki-43 I...................................236.8
Ki-43 II..................................230.4
Hurricane.............................257
Spitfire..................................242
Typhoon..............................279
F2A Buffalo........................208.9
P-39......................................213
P-40......................................236
Ki-84.....................................226
N1K1-J.................................257
F4F-4....................................260

Are you cherry picking a bit here? Let's add to the list:

Fw 190 197 sq ft
Bf 109 174.4 sq ft (some variants 176.6..?)
Yak-1/7/9 184.6 sq ft
Yak-3 159.8 sq ft
MC 202 / MC 205 181 sq ft
MC 200 181 sq ft
G.50 196.4 sq ft
Polikarpov I-16 156 sq ft
LaGG-3 187-190 sq ft (depending on precise variant)
La 5FN 188 sq ft
La 7 189.3 sq ft
IAR 80 183 sq ft
Ki 27 199.8 sq ft
A5M 191.6 sq ft

I bolded the ones which were considered among the best fighters in the war. It's about even comparing one list to the other, though you could also add Hellcat, P-51, Fiat G.55 and a few other successful beasts. All designs from quite late in the war I might note. But Spitfire, I would also note, like the Ki-43 and A6M, was a small aircraft with big (but thin) wings. (I'd also note that a clipped wing Spit has 210-215 sq ft). So I claim them for my list, or maybe they belong in a middle list. That's quite different from a plane like a Hurricane or a Fulmar which is massive with massive wings, or something gigantic like a P-47 or Typhoon or Tempest. Or a Firefly.

P-38 has big wings but I wouldn't group it with the giants, as it's rather slim and sleek.

The main French fighters are with the smaller group:

D.520 171 sq ft
Bloch 152 186 sq ft
MS 406 170-172 sq ft
VG 33 150 sq ft

The VG 33 / 36 / 39 is certainly in the lower end here but I'd say it's in quite good company with the Yak 3. This would likely make the VG 33 an interceptor / battlefield fighter but if it was successful, they could always make a larger wing for it.

Just about all of the French, Italian and Soviet fighters were under 200 sq ft or just over.
F2A was fat, but it was short. around 3 feet shorter than some of the other planes.
Typhoon was one of the first single engine single seat fighters to be around 11,000lbs.
Hawker didn't advance the state of art in flap design much over the Hurricane.
Every designer in every country used the size wing he thought needed to meet the requirements. Maneuverability, Field performance, storage for guns/ammo or fuel, Landing gear.

And yet, it's notable that the rather small Dewoitine D.520 for example had a cannon, armor, self sealing fuel tanks, and carried 168 gallons of fuel, 105 in the fuselage and 63 in the wings for a strait line range of 620-780 miles. Which is better than a Spitfire V, Bf 109F or Yak 1. It also achieved a reasonable wing loading of 34 lb / sq ft which is quite competitive (better than a Bf 109F4 or G2).

XP-39 needed to hide 200 US gallons (757liters) in the wings, no fuel in the fuselage. Then came the requirement for self-sealing tanks and 80 gallons went away while they kept the existing wing (or at least it's shape).

It is not as bad as you think. Typhoon had a lot of trouble with engines. They tried 3 different ones. F4U saw a lot of changes, but the engine was not trouble free either. The basic engine was OK. The two stage supercharger gave some trouble.

What I'm saying is Typhoon or Corsair, as new (and large, ambitious) aircraft designs are a more difficult design path precisely because they are new designs. Any improvement on the D.520 is building on an existing design we know worked, same with the Bloch or MS, and the Arsenal VG 36 or 39 would just be variation on a design that was already in production in 1940.

Problem I have with the French wonder planes is they need extensively modified engines in existing airframes. Air frames maybe fine (or not, the D 551 is suspect, for one) but the higher powered Hispano engines are a real quagmire. basically take 900-1000hp engine. Slap new cylinder heads on it (more valves), increase the boost, increase the rpm, and expect and engine that had trouble lasting 100 hours at the lower power levels to be just fine at higher power levels.
Or expect the GR 14R to be a somewhat trouble free engine in 1940-41 when they had little run time on the bench in 1940-41. About all the 14R kept from the 14N was the bore and stroke. New crankcase, new crankshaft, new rods, new pistons, new cylinders, new cylinder heads and list goes on.

Any time, I repeat, ANY TIME, I see reports of amazing performance of both speed and climb in a single test, especially the first test flight, the bullshit meter pins it's needle to the side of the gauge. The Bloch 157 didn't even fly until 1942.
Bloch 157 may have been a fine airplane but the engine is a real problem. The article linked to
Bloch MB.157
seems to claim that a turbo-compressor in two-stages was used. Other sources may say this but it is the only time I have seen it. Photos show no evidence of a turbo-compressor.

Yes, I saw the same article, it does seem a little far fetched, I don't know. I assumed 'turbo-compressor in two stages' meant two stage or two speed supercharger, but I really don't know. Another poster mentioned that they only had a single stage.

Thing is, I don't think we need super planes to make the French competitive. The VG 33 and D.520 already look pretty good. Their immediate, incremental successors look a bit better, and would see the French quite competitive well into 1941. After that they can make a more radical change to one of the existing designs (ala P-51A to B) or come up with something else new or develop one of their more long shot ideas. We can only really extrapolate so far, but for me, the French air arsenal while it has a few duds (Potez 630 I'm looking at you) it does seem to clearly have some winners by the standards of the first half of 1940. Let's keep in mind what the US actually had in production in May-June 1940, because it wasn't Corsairs, Mustangs or Hellcats.

 

[Shortround6]

Are you cherry picking a bit here?

Not really, just being a bit lazy. And showing that the Japanese fighters were in a larger class than the 'European' fighters (French, German, Italian, Soviet)

I bolded the ones which were considered among the best fighters in the war.

Best where?
Most of these would have been failures in the Pacific. You can't be among the best it you can't reach the fight.
Many nations designed their fighters with specific goals in mind.

clipped wing Spit has 210-215 sq ft).

Which clipped wing Spit? The prototype Mk III or all of the clipped wing service Mks?
All of the service Mks had 231 sq ft wings.

Fulmar which is massive with massive wings, or something gigantic like a P-47 or Typhoon or Tempest. Or a Firefly.

Fulmar was a hasty lash up of a 2 seat bomber. Firefly was another two seater. And they wanted more range and the ability to land on a carrier, which the 150-180 sq ft fighters were going to have a lot trouble with.
You can't stick 2500lb engines into fighters that use the same size wings as fighters that use 1400-1500lb engines. And a lot of the 150-180sq ft fighters were designed for engines that weighed between 950-1250lbs. (Jumo 210, H-S 12Y and Fiat A 74. Smaller engines also mean they need less fuel for a given endurance.

D.520 171 sq ft
Bloch 152 186 sq ft
MS 406 170-172 sq ft
VG 33 150 sq ft

These planes would work in 1940, not so much in 1941 but that is because of the engine/s. If you are satisfied with the 1940 armament and/or range or 1940 protection then all is good in 1941-42 if you can get more power out of the engines and not join the hand grenade of the month club.

And yet, it's notable that the rather small Dewoitine D.520 for example had a cannon, armor, self sealing fuel tanks, and carried 168 gallons of fuel, 105 in the fuselage and 63 in the wings for a strait line range of 620-780 miles. Which is better than a Spitfire V, Bf 109F or Yak 1. It also achieved a reasonable wing loading of 34 lb / sq ft which is quite competitive (better than a Bf 109F4 or G2).

The self sealing tanks may be subject to question. In 1940-41 a lot of people played fast and loose with the term 'self sealing' which is not the same as protected. I am looking at the Spitfire and others here. I would like to see better information on the D 520 but I seem to remember there was a difference between the fuselage tank and the wing tank/s. There was also a CG problem with the wing tanks. Perhaps the reverse of the problems with the P-36, Spitfire and P-51?

Any improvement on the D.520 is building on an existing design we know worked, same with the Bloch or MS, and the Arsenal VG 36 or 39 would just be variation on a design that was already in production in 1940.

The problem is not with the airframe/s but with the engines. The 12Y was pretty much maxed out for a number of reasons. So was the GR 14N.
The 12Z and 14R both require development, testing and retooling.

Let's keep in mind what the US actually had in production in May-June 1940, because it wasn't Corsairs, Mustangs or Hellcats.

Very true. The P-40 was barely in production in May (11) and June (25).
Now compare the P-40 and P-40B to the smaller French aircraft.
And the crucial difference was that the P-40 had growth potential.
The US did not capitalize on some the potential, in part because Allison had trouble with superchargers and in part because the Americans insisted on six .50 cal guns and hundreds of pounds of ammo but that was not the airframe's fault.
P-40 was supposed to be good for 357mph at 15,000ft and had a gross weight of 6807lbs with 120 gal of fuel.
BTW the wing loading of the P-40 at normal gross was 28.84 and at max gross (181 gal fuel and a bit more oil) the wing loading was 30.39.
Yes by the time the P-40E gets into service these loadings had been blown to hell but P-40 had room for growth.

Rate of climb was about 3000fpm.
Granted the P-40 had zero protection.
P-40B gained 545lbs with the same 120 gal fuel due to increased armament and protection.

I am not seeing the room for growth in 150-180 sq ft wing fighters.
Spitfire went from a 5800lb fighter (service) to a 7800lb fighter (Mk VIII).
I am not seeing a 30-33% increase in weight for the small fighters and still keep decent flying qualities.

 

[ThomasP]

The Spitfire wing spans and wing areas are confusing. It took me a while to find all the specifications.

Spitfire Mk V thru Mk XIX wing span & area - except for the Mk III and the Spiteful (nee Spitfire Mk XIV*)
______Extended_____40' 2" x 248.5 ft2
______Standard_____ 36'10" x 242 ft2
______Clipped______ 32' 6" x 231 ft2 (sometimes given as 230 ft2)

Spitfire Mk III
______Clipped______30' 6" x 220 ft2 (original modified wing design with squared off wing tips**)

Spiteful Mk XIV, XV, XVI
______Clipped______35' 0" x 210 ft2 (totally new wing planform with straight leading and trailing edges)

* The Spiteful was originally named the Spitfire Mk XIV. After changing the name to Spiteful, the Spitfire Mk XIV designation was reused and instead given to a 'standard' Griffon powered Spitfire variant.

** The Spitfire Mk III originally had a clipped wing of the same elliptical planform as the standard Spitfire wing, but with reworked internal structure. The new wing was not considered worth putting into production, and both(?) prototypes were subsequently fitted with the standard Spitfire wing and testing continued with both normal, extended, and clipped wing tips.

 

[tomo pauk]

I would not be too worried about the wing size of the 'continental' fighters.
Fw made the original 190 with a wing smaller than what the 109 had. Heinkel made the He 100 to be of small size (I'm not talking about the racing versions with an even smaller wing), that probably had a lot to do with the big & draggy He 112 loosing vs. the small & sleek 109 of the mid-1930s. Dewoitine was designing the D.551 fighter to be even smaller than the D.520. Yakovlev's team made the Yak-3 even smaller than the already modest Yak-1 and -9.

French fighters will have one task - beat the Germans that are just behind the frontline, or even on the French side of it. They will not care a single bit that their best fighters are not that good when navalized. Small size can cut the drag, that comes in handy when the engine power increase is not guaranteed.

 

[Shortround6]

I would not be too worried about the wing size of the 'continental' fighters.
Fw made the original 190 with a wing smaller than what the 109 had. Heinkel made the He 100 to be of small size (I'm not talking about the racing versions with an even smaller wing), that probably had a lot to do with the big & draggy He 112 loosing vs. the small & sleek 109 of the mid-1930s. Dewoitine was designing the D.551 fighter to be even smaller than the D.520. Yakovlev's team made the Yak-3 even smaller than the already modest Yak-1 and -9.

French fighters will have one task - beat the Germans that are just behind the frontline, or even on the French side of it. They will not care a single bit that their best fighters are not that good when navalized. Small size can cut the drag, that comes in handy when the engine power increase is not guaranteed.

The small size suited, somewhat, the European conditions. Germans thought, even in 1940, they had the long range problem solved with the bf 110 or with the Me 210. We know how that turned out. But they didn't know at the time and so it didn't affect some of their purchasing/percurment plans.
French also were buying, building twin engine fighters.
So were the Italians, their try didn't work very well.
Soviets were trying. They also did not replace the Yak-9 with the Yak-3. They built both and had the special long-range versions of the Yak-9s which held more internal fuel.
Soviets also the problem with trying to improve the Hispano 12Y significantly.
Soviets wanted to use more firepower. The repeated failures of the M-106, M-107 and the M-108 forced retention of the M-105 engine in its later versions.
I will also note that in the Yak-3s had several operational limitations. It was a great air defense fighter. Not so good in support of ground troops or bomber escort (tactical bombers?) due the limited endurance. Average mission duration being about 40 minutes, try that in the Pacific. Granted the soviets tended to cruise at very high speeds.
It also took until batch 13 for the soviets to restore the 2nd 12.7mm UBS machine gun. Most early batches had one 20mm and one 12.7mm gun. Late 1944 and 1945 combat meant the heavier armament was more suited (German air to air was falling off a bit?)
Americans dabbled with twin engine fighters, only the P-38 was built in quantity, and it shows the both the problems and possabilities of large fighters.
British tried with the Whirlwind but somebody decided that one 24-cylinder engine was a better bet than two 12-cylinder engines.

French have another important fighter mission with near the front lines. They need to ensure the safety of French reconaissance aircraft and French strike aircraft on interdiction missions (cutting German supply).

 

[tomo pauk]

The small size suited, somewhat, the European conditions. Germans thought, even in 1940, they had the long range problem solved with the bf 110 or with the Me 210. We know how that turned out. But they didn't know at the time and so it didn't affect some of their purchasing/percurment plans.

True.

French also were buying, building twin engine fighters.
So were the Italians, their try didn't work very well.

Neither of them were making the bespoke 2-engined fighters, bar prototypes.
French purchase of the Lightnings probably had a lot to do with 'let's buy stuff that can help us survive, and fast', rather than 'let's be cheeky and hit Germans in Berlin'.

Soviets were trying. They also did not replace the Yak-9 with the Yak-3. They built both and had the special long-range versions of the Yak-9s which held more internal fuel.
Soviets also the problem with trying to improve the Hispano 12Y significantly.
Soviets wanted to use more firepower. The repeated failures of the M-106, M-107 and the M-108 forced retention of the M-105 engine in its later versions.

Again, true.
Soviets were operating - or at least trying to operate - on the greater distances than it will be required in a Franco-German war; the long-range cludge was also a reply to the wartime experience that French, per this scenario, are just about to get a year or two in future.
Soviets were also somewhat the converts to the 'bomber will always get through' church. The relative success of the SB in Spain and in China fortified that faith. It backfired badly in 1941.

I will also note that in the Yak-3s had several operational limitations. It was a great air defense fighter. Not so good in support of ground troops or bomber escort (tactical bombers?) due the limited endurance. Average mission duration being about 40 minutes, try that in the Pacific.

The reasoning why would the Soviets try to make a fighter in 1943/44 to deal with Pacific distances is beyond me.
A fighter is a fighter. It must do it's job good. Soviets rarely deployed their 1st line fighters as mud movers, so, again why would that disqualify the Yak-3 in their eyes, as well into the eyes of the German pilots and other airborne crewmen at the receiving end?
That Soviet high command didn't see fit to specify the Yak-3 (and other fighters) to be outfitted with drop tanks is not something that should be pinned on the Yakovlev design team.

French have another important fighter mission with near the front lines. They need to ensure the safety of French reconaissance aircraft and French strike aircraft on interdiction missions (cutting German supply).

Of course.
For that they need the fighters that are competitive vs. the enemy fighters. The more belly fat these fighters have, the worse are they in their task.

 

[Steamed_Banana]

There is no doubt that a P-47 was a more versatile fighter, in the sense of being more suited to a wider array of battlefield missions and Theater requirements, than the Yak-3. It had a role in the Med, the Pacific, NW Europe, and CBI.

But does anyone really believe that the P-47 would have done better, or even remotely as well, as a VVS type tactical fighter for the Soviets over their front line with the Germans? The Soviets themselves certainly didn't. They could have had them if they wanted them.

 

[Dimlee]

There is no doubt that a P-47 was a more versatile fighter, in the sense of being more suited to a wider array of battlefield missions and Theater requirements, than the Yak-3. It had a role in the Med, the Pacific, NW Europe, and CBI.

But does anyone really believe that the P-47 would have done better, or even remotely as well, as a VVS type tactical fighter for the Soviets over their front line with the Germans? The Soviets themselves certainly didn't. They could have had them if they wanted them.

My "dream VVS" would replace the Il-2s (and some Pe-2s) with the P-47 in 1944. Off-topic, I know.

 

[Shortround6]

Neither of them were making the bespoke 2-engined fighters, bar prototypes.

Both the Germans and French got sucked into the Multi-place aircraft type, which was also multi-role. Timing is important as 1930s aircraft radios sucked. Both sides thought there was a place for 2-3 seat combat aircraft that could act as fighters or bomber interceptors and act as fighter leaders providing navigation and long-range communication for the single seat fighters. Sometimes they also thought that a unit commander could act as a mobile command or fighter direction center. He was in the middle of the fight after all (or on the edge) instead of on the ground unable to see his aircraft. We know this did not work, like a lot of other theories. But the aircraft that were built to try to fill out the requirements stuck around. Reason for three seats in the Bf 110?
France had the Potez 630. They also adapted to several other rolls. Unfortunately, it was designed to a 1934 specification and in French fashion, it ran late, the initial engine selection was a failure and by the time it went into service in numbers it was horribly obsolete for some of it's intended roles. A pair of 700hp engines in 1934-37 might have been seen as quite up to date. In 1939-40 it was a death trap.
For the Italians the IMAM 57 comes to mind

Most of the 50-75(?) built (out of 200 ordered) were converted to fighter bombers. It might have been a good idea in 1939. By the end of 1940 it was not.

The reasoning why would the Soviets try to make a fighter in 1943/44 to deal with Pacific distances is beyond me.

It is just pointing out that different fighters had to meet different requirements and that small does not always equal good. Criticizing the US for making big fighters is ignoring the actual needs of the US.

That Soviet high command didn't see fit to specify the Yak-3 (and other fighters) to be outfitted with drop tanks is not something that should be pinned on the Yakovlev design team.

There was no need to fit drop tanks to the Yak-3s, they had the YAK-9Ds and the YAK-9DDs but the YAK 9DD does point out a problem with small fighters. Putting 185 gal of fuel inside a fighter designed for about 96 gal was possible but the weight increase called for sacrifices in other areas or a loss of performance.
In 1944 the Soviets could afford to build specialty fighters.

 

[Bretoal2]

As for France, a successor to the Potez 630 was undergoing trials at the time of the June 1940 armistice: the Potez 671. It was designed to use engines significantly more powerful than the Hispano-Suiza 14AB (HS 14AC) or Gnome-Rhône 14M (G&R 14S "Super Mars"). None of these engines were ready in time, so the 671 flew with older-generation engines. While it naturally delivered better performance than the 630 thanks to its refined airframe, it fell short of the capabilities expected from the new powerplants.

Potez/SNCAN had also developed—albeit without much conviction—a project originally conceived by ANF-Les Mureaux (which had joined the group during the nationalizations). This Potez 220 was a twin-engined aicraft intended for observation and "commandement à la chasse". It differed little from the Potez 63 and, like its predecessor, was underpowered relative to the performance required at the outbreak of the conflict.

At Breguet, the 693 was fitted with 1,060 hp G&R 14N engines, becoming the Breguet 700. This somewhat risky combination yielded exceptional performance, but the engines—with a diameter 34 cm larger than the originals—severely obstructed visibility and compromised the controls balance. This aircraft was in its very initial flight-test phase in June 1940.

Finally, one must not overlook the formidable Sud-Est 100—a heavily armed twin-engine fighter designed by engineers Mercier and Lecarme. Two prototypes were built, though one was accidentally destroyed. It appears to have offered performance at least equal—if not superior—to that of the Me 110, while boasting a much heavier armament of multiple 20 mm cannons. However, France was not yet aware of the difficulties the German twin-engine fighter would eventually encounter.

That covers the twin-engine aircraft that were actually built and tested (albeit very briefly in the case of the Breguet 700); there were also numerous projects from various manufacturers that never leaved the drawing board !