A Radial Engined Fighter for the Australians to build (and maybe the Chinese and Indians)

[Wild_Bill_Kelso]

The Australians were hampered with the fact that they had to work with what they had and the Wirraway airframe as the basis of the Boomerang was not as much a hindrance as the power output of available engines. If Aussie needed a more advanced fighter it would have had to import something, as construction would have taken too long. The P-36 as Tomo mentioned is a very good option, as is the Hawker Hurricane, but the P-40 is essentially what Australia got by negotiating with the US. It's first P-40Es were transferred from USAAF stocks and arrived in March 1942, before the first Boomerang had been completed - it made its first flight in May 1942. Over the next month into April and May these P-40s were already in squadron service and went into action at Port Moresby, so whatever choice is made has to be done fast, because the RAAF already has orders for more P-40s diverted from RAF Lend-Lease.

The other alternative is getting single-seat fighters before the fighting begins, at which point that options for building a panic fighter are restricted to being a type based off the Wirraway as it was traditionally done, but the RAAF is looking long term, which means something off the shelf, which either the P-36, P-40 or Hurricane make better long-term choices given what was going to happen, rather than a panic fighter.

I don't see it as an either-or thing. The P-40 worked out very well for the Australians, after a little rough patch getting up to speed with them and figuring out tactics against the Japanese, but i don't think they could produce them, at least not early on, in part because they weren't producing Allison engines or any near equivalent. But they did have the 1830. Which is why yes, the P-36 and some other types would have been good.

I don't think the Hurricane was a good candidate as it did very poorly against Japanese fighters, at least from what I've read, especially in the China / Burma zone.

Probably several of the types mentioned, Gloster F.5, P-36, P-66, maybe even the Buffalo, could have been adapted by the Australians and manufactured there. I wouldn't expect them to cut down on the number of P-40s they were getting, but the slightly slower but still capable P-36 or F5 or whatever could augment the P-40s in many places and also help as a transitional aircraft / advanced trainer for pilot training. P-40s had a bit of a learning curve for pilots.

The idea is for the Aussies to make something simple they can use for air defense on the more remote islands and coastlines, as home defense units for their larger cities away from the combat zone, for training, and / or in a secondary role as close air support etc. the way they tried to use the Boomerang, and also as something they could export to places like India and China,. They can still use P-40s for the hard core combat zone where the fighting is thickest. If they could have made something like a Gloster F9 that might have been more significant.

 

[Wild_Bill_Kelso]

The Australians were hampered with the fact that they had to work with what they had and the Wirraway airframe as the basis of the Boomerang was not as much a hindrance as the power output of available engines. If Aussie needed a more advanced fighter it would have had to import something, as construction would have taken too long. The P-36 as Tomo mentioned is a very good option, as is the Hawker Hurricane, but the P-40 is essentially what Australia got by negotiating with the US. It's first P-40Es were transferred from USAAF stocks and arrived in March 1942, before the first Boomerang had been completed - it made its first flight in May 1942. Over the next month into April and May these P-40s were already in squadron service and went into action at Port Moresby, so whatever choice is made has to be done fast, because the RAAF already has orders for more P-40s diverted from RAF Lend-Lease.

The other alternative is getting single-seat fighters before the fighting begins, at which point that options for building a panic fighter are restricted to being a type based off the Wirraway as it was traditionally done, but the RAAF is looking long term, which means something off the shelf, which either the P-36, P-40 or Hurricane make better long-term choices given what was going to happen, rather than a panic fighter.

I think some of those aircraft listed in the OP were made of non-strategic materials to at least some extent, though the P-36 was indeed stressed-skin. That might be a reason to go with one of the other ones...

 

[nuuumannn]

That might be a reason to go with one of the other ones...

Again it's all about timing. The Boomerang could be built and put into service with minimal delay because it was based on the Wirraway already in production. Introducing another type for production does slow things down a bit regardless of how its constructed. Bear in mind that the RAAF's first P-40s were first received in March 1942 and there was orders for more. This is my point, when exactly are the Australians going to put an order for these suggested types into service versus Boomerang development and production and the introduction of the P-40E into RAAF service?

 

[MiTasol]

I have spent a lot of time looking at the Aus Archives and I am yet to find an order for P-40 aircraft prior to late 42. Likewise in US documents.

This suggests that the first P-40s were actually just given to the RAAF by the US. Supporting this is the fact that there are documents that show the US was looking at giving the 49th Fighter Group - complete - to the RAAF and later, after that plan was discarded, other documents from the US asking where the hell are the RAAF P-40s when they considered more than enough time had passed for the first squadrons to be operational.

 

[don4331]

Are there any 2 speed R-1830 engines that aren't 2 stage? I thought the Twin Wasp was like the Double Wasp and the "multi" speed was only in the 2nd stage. Which is going to limit your radial engined fighter right out of the box. (I need an answer on that before building the rest of the plane).

 

[Shortround6]

For all the people that think the P-36/Hawk 75 was the greatest thing since sliced bread the Americans figured that the P-36 had 22% more drag than the early P-40. This may or may not include exhaust thrust.
On the WWII Aircraft Performance website there are some tests that give cruising speeds for the P-36 and the early P-40 at different power levels. Look them up and see what the difference was.
I would also note that the Americans were doing a pretty good job of putting cowlings on radial engines at the time (1939-1941) the FW 190 was sneaking in near the end but a lot of people were using some pretty dismal radial engine cowlings in the late 30s.

P & W did get the drag down to about 8% on their P-40 test hack with the two stage R-1830 engine developed from the engine in the F4F wildcat. Of course it took about 2 years to do it (flying around in mid or late 1942) and the fact that the two stage engine allowed it to fly in the thin air at over 20,000ft while still making decent power made it the 4th fastest P-40 to fly in WW II (the fact it had no armor, no self sealing tanks and no guns didn't hurt either).

And if you want the P-35/ Hawk 75 performance as built you have to put up with the light armament (six .30 cal guns at best) and the sketchy protection. Adding a few hundred pounds of SS tanks and BP glass etc (some did have armored seat backs) starts affecting the performance.

A P & W R-1830 with two speed supercharger weighed close to 150lbs more than an Allison which cancels some of the weight saving of ditching the radiator. It will burn more fuel giving shorter range on combat missions.

 

[Shortround6]

Are there any 2 speed R-1830 engines that aren't 2 stage? I thought the Twin Wasp was like the Double Wasp and the "multi" speed was only in the 2nd stage. Which is going to limit your radial engined fighter right out of the box. (I need an answer on that before building the rest of the plane).

There wound up being fair number. But they didn't show up until 1940. I haven't read about any being used in 1939.
Take a good look at the R-1830s with two speed superchargers. There may have been a cooling problem?

The engine used in the Vultee P-66 was two speed But the hi speed was good for 1050hp at 13200ft. using 90 0catane?
The engine used in the F4F-3A was good for 1000hp at 14500ft at 2700rpm using 100 octane. That was the rating for the Australian Beaufort engines too.

 

[nuuumannn]

I don't think the Hurricane was a good candidate as it did very poorly against Japanese fighters, at least from what I've read, especially in the China / Burma zone.

Said with the hindsight of knowing what had happened. They would not have known that at the time an order would have been put. The Hurricane was a plenty good fighter in the right hands in the right conditions in 1940/1941. British losses in Singapore were down to a lot of mitigating factors, the performance aspect of the type wasn't necessarily a factor in its failure as a fighter in theatre. The British were up against superior numbers, they had little support, no radar warning etc etc. Even the best fighters in the world would have suffered losses in theatre and would not have prevented Japan's subjugation of Singapore.

I have spent a lot of time looking at the Aus Archives and I am yet to find an order for P-40 aircraft prior to late 42. Likewise in US documents.

This suggests that the first P-40s were actually just given to the RAAF by the US.

They were, but not all of them, some were from British lots and had British serials. From March 1942 the RAAF received a stream of them through every month that year. According to the books, 153 aircraft from the British Defence Aid DA-3 contract were shipped to Australia from San Francisco beginning in March 1942, of which 14 were sunk on route and were not replaced.

 

[Howard Gibson]

Reading about the Boomerang and the Wirraway, it's clear that the nascent Australian aircraft industry had some capability, and they were eager to produce some aircraft with which to contribute to the war effort and to their own regional defense, instead of just waiting for aircraft to arrive from England or the US.

The problem with the Boomerang of course is that it was based on a trainer, so no matter how much they improved the design around the margins, they still had an aircraft that wasn't going to be able to tangle with Japanese fighters, or for that matter chase down and intercept most Japanese bombers.

So what if we pick another airframe and equip it with an Aussie made R-1830 engine. Which would would be in the sweet spot of easy to adapt, relatively easy to produce, capable enough as a fighter, and have the potential to be improved into a better fighter.

The basic problem is the 30litre R-1830 engine. The successful WWII radial engines were big, with the prime example being the Pratt and Whitney R-2800 at 46litres. The 28litre Nakajima Sakae engine got the later Mitsubishi Zeros up to around 350mph, but they sacrificed protection to do it.

The whole point of the Wirraway is that it was in production in Australia at the time. Much of the tooling could be used on the Boomerang.

 

[wuzak]

Maybe a little far-fetched (conversions from in-line) but still maybe worth considering

Avia B.35
Westland Whirlwind
Hawker Henley
Dewoitine D.520

I don't know what the fascination about a radial engine Whirlwind is.

In this context it would be a very poor choice, since it would have to be re-engineered for the R-1830s, which would set back production significantly.

So what if we pick another airframe and equip it with an Aussie made R-1830 engine. Which would would be in the sweet spot of easy to adapt, relatively easy to produce, capable enough as a fighter, and have the potential to be improved into a better fighter.

Some possible candidates:

Brewster B.239 / Buffalo
Bristol Beaufighter*
Fiat G.50**
Fokker D.XXI
Gloster F-5/34
Gloster F9
P-36 / Hawk 75
Re 2000**
Seversky P-35

* I think (?) they did eventually make some of these but what if they got the ball rolling on this earlier? The Beauforts were certainly worth producing.
** Assuming they could have gotten the License from Italy before the war started

Any of these seem like they could have been feasible? It seems like a slightly improved Gloster F-5, Fokker D.XXI or P-36 could have been within the capabilities of CAC and may have been somewhat useful for Australia's emergency needs and some of the other regional allies.

The Glosters were never put into production and are often referred to by the Air Ministry specification number. So they are the Glost F.5/34 and F.9/37.

In your list the only really viable option, IMO, is the P-36/Hawk 75.

The Gloster F.9/37 used the Taurus, just as the Beaufort did. Converting to R-1830s would be OK, but the aircraft was not production ready.

The Gloster F.5/34 was probably passed its time.

The Brewster Buffalo? Possible as an alternative, but would you want a Buffalo over a P-36?

The Beaufighter started out as a fighter based on Beaufort bits, but really only retained the wing? It also had the larger, more powerful Hercules, so fitting them with R-1830s would not have resulted in a very good aircraft.

Don't know much about the Fokker D.XXI. Its performance seems lower, and it was designed around a less powerful engine. How much extra work needed to get the R-1830 to fit and work with the airframe?

The Seversky P-35 was a bit down on performance compared to the P-36A (R-1830). It had better armament, though.

The Italians I also do not know much about.

The Re 2000 first flew in 1939, giving about a year to get it into production and a licence deal done with Australia. Probably not going to happen, since the prototype had some issues.

The FIAT G.50 was in production, and service, before WW2. From that point of view it was possible. It was another light aircraft with a small engine, though a prototype was made with an engine of similar power to the R-1830.


I'm not sure which in the list have much in the way of development potential.

 

[Geoffrey Sinclair]

The first Australian built Single Row Wasp was produced in January 1939, then 1 in April, 3 in May then production from July onwards. One reason for the choice was the Twin Wasp was is a simple step up as far as production was concerned. However through the Australian production run some parts needed to be imported (cylinder barrels?)

The decision to build the Pratt and Whitney R-1830 Twin Wasp in Australia by the Commonwealth Aircraft Corporation (CAC) was taken on 31 October 1939, first production was in November 1941, in the end 870 were built, versus the need for 1,650 new engines for local production Beauforts and Boomerangs. The idea of producing Twin Wasps was around as part of the March 1939 proposal to build Beauforts in Australia, initially it was assumed they would use imported Taurus engines, but continuing doubts about the Taurus resulted in the British proposing the Australians build the Twin Wasp, that was turned down, the British asked for a reconsideration, the Australians then decided to build the engines with the message agreeing to the production crossing one from Britain that said no need, Taurus production would be sufficient.

The decision to build Beauforts was made in late March 1939, but was delayed by inexperience, the 1940 crisis, the Taurus engine problems and Twin Wasp redesign, first Australian production in August 1941.

The Vengeance was the substitute for the Bermuda which had been scheduled to arrive in 1941, 5 Vengeance arrived in Australia in May 1942, 10 in July, then imports from February 1943.

Early P-40 imports that ended up in the RAAF were 162 March to September 1942, then further imports from January 1943.

The first 6 Spitfires arrived in August 1942, then imports from October 1942 onwards.

The first Beaufighters arrived in March 1942, local production was approved in January 1943, production began in March 1944 (the aircraft were costed at 40,000 pounds each, tooling at 700,000 pounds).

While 2 Boomerangs were flying by end July 1942 the usual teething problems meant official production began in September.

In 1941 Australia was producing 3 types of trainers, Wirraway using locally built engines, Tiger Moth with local engines and the Wackett trainer using imported engines. Trainer production was shut down by end August 1942, the Wirraway resumed production in November 1943 and a batch of 35 Tiger Moths were built 1943/44. Tiger Moths were exported to New Zealand and South Africa, the latter without engines.

The choice of the Wirraway design, and subsequent Beaufort, was to have in production an aircraft with all the latest features, including enclosed cockpit, retractable undercarriage and stressed skin construction, to create a modern industry, as things were changing fast. The P-51 kits North American put together for Australia were D-5 in March/April 1944, then add weeks to months to pack the kits, get them across the Pacific, unpacked and assembled, assuming everything is perfect. In June 1944 the P-51D-10 was in production, the D-15 in August, the D-20 in October, creating a real problem for Australia building up to date versions.

Note the Australian industry's limited capacity and lead times, also check out the stories of the CA-4 and 11 bombers, and the CA-15 fighter, even the supercharged Boomerang. If the RAAF is to have a modern fighter in local series production in early 1942 decisions on engine and airframe need to be taken in 1939 to early 1940 and would need to be a type in production so tooling could be more readily copied. The P-35A ended production in January 1941. Curtiss CW-21B built October to December 1940. P-66 production was October 1941 to April 1942, despite some British interest, most shipped to India for China, starting in February 1942. YP-43/P-43/P-43A production from September 1940 to April 1942, the RAAF did not like the P-43. F2A production ended in April 1942.

The R-1830 is really not powerful enough for a front line 1942 fighter unless some compromises are made on protection.

Wild card solution, NA-73 when the British ordered it, as part of a long term Australian Mustang production plan, first NA-73 produced in August 1941, added to Australian Merlin production which would also serve the local Mosquito program, the major hindsight picking the winners solution, Australia did built Merlin for its Lincoln bombers, but not until June 1947.

The 162 early RAAF P-40 were a mixture of P-40E-1 from the RAF order DA-3 (including 9 sent for the Netherlands East Indies but treated locally as USAAF) and P-40E from the USAAF orders. The RAAF were allocated 250 P-40 from DA-3 in January 1942, the RAAF thought it was going to receive 173 in early 1942, the allocation became a firm commitment for 143, of which 14 were subsequently lost at sea and not replaced. Upon arrival the P-40E and E-1 were assembled by whichever RAAF/USAAF unit had the capacity then allocated and even reallocated between the RAAF and USAAF, the RAAF ended up with 66 P-40E-1, another crashed on the delivery flight, hence 163 RAAF P-40E/E-1 serials. The difference of 162 P-40 to the RAAF versus 129 imported was partly repaid in 1944 when 20 RAAF lend lease P-40N were transferred to the USAAF. The first 78 RAAF P-40 serials were P-40E.

P-40 Order status as of 1 March 1943. A1196 1/501/466 part 5, page 162. First allocation was notified by the Secretary of State for Dominion Affairs, London in Cable No.138 dated 31st January 1942, for 250 aircraft, subsequently amended to a firm allotment of 143 machines. Australian War Cabinet Minute No.1845 Agendum 46/1942 authorised the acquisition.

 

[Admiral Beez]

P-36 all the way.

Agreed. Really this discussion should be trying to justify why not the P-36, since it's the obvious choice.

And once the Pratt & Whitney Twin Wasp R-1830-76, featuring a two-stage supercharger is available the RAAF can field a P-36 Super Hawk, the best P-36 variant never made.

The R-1830 is really not powerful enough for a front line 1942 fighter unless some compromises are made on protection.

Isn't that the engine that powered the Wildcat at Midway in June 1942? It seemed up to the task.

 

[EwenS]

Isn't that the engine that powered the Wildcat at Midway in June 1942? It seemed up to the task.

The F4F Wildcat entered service in mid-1940. June 1942 saw production of the 2,000hp R-2800 powered Vought F4U Corsair starting, followed by the similarly powered Grumman F6F Hellcat in July. While the F4F may have been "up to the task" at Midway it was clearly aready seen as past it.

 

[Wild_Bill_Kelso]

I have spent a lot of time looking at the Aus Archives and I am yet to find an order for P-40 aircraft prior to late 42. Likewise in US documents.

This suggests that the first P-40s were actually just given to the RAAF by the US. Supporting this is the fact that there are documents that show the US was looking at giving the 49th Fighter Group - complete - to the RAAF and later, after that plan was discarded, other documents from the US asking where the hell are the RAAF P-40s when they considered more than enough time had passed for the first squadrons to be operational.

I thought the first batch were diverted from Java

 

[Wild_Bill_Kelso]

For all the people that think the P-36/Hawk 75 was the greatest thing since sliced bread the Americans figured that the P-36 had 22% more drag than the early P-40. This may or may not include exhaust thrust.
On the WWII Aircraft Performance website there are some tests that give cruising speeds for the P-36 and the early P-40 at different power levels. Look them up and see what the difference was.
I would also note that the Americans were doing a pretty good job of putting cowlings on radial engines at the time (1939-1941) the FW 190 was sneaking in near the end but a lot of people were using some pretty dismal radial engine cowlings in the late 30s.

P & W did get the drag down to about 8% on their P-40 test hack with the two stage R-1830 engine developed from the engine in the F4F wildcat. Of course it took about 2 years to do it (flying around in mid or late 1942) and the fact that the two stage engine allowed it to fly in the thin air at over 20,000ft while still making decent power made it the 4th fastest P-40 to fly in WW II (the fact it had no armor, no self sealing tanks and no guns didn't hurt either).

And if you want the P-35/ Hawk 75 performance as built you have to put up with the light armament (six .30 cal guns at best) and the sketchy protection. Adding a few hundred pounds of SS tanks and BP glass etc (some did have armored seat backs) starts affecting the performance.

A P & W R-1830 with two speed supercharger weighed close to 150lbs more than an Allison which cancels some of the weight saving of ditching the radiator. It will burn more fuel giving shorter range on combat missions.

I certainly don't think that the P-36 was "the greatest thing since sliced bread" - it wasn't even as good as a P-40 and we know that wasn't an ideal fighter. But the P-36 had a proven track record in combat (Battle of France) and was deemed good enough by the British to still try to use them in Burma in 1944. I think in a secondary role it would have probably been better, and had more potential for improvement, than the Boomerang. Probably a few of the other fighter types mentioned could have as well.

Presumably the Aussie R-1830 could have provided sufficient extra power for more armor, SS tanks and more guns for whichever aircraft was chosen. As for armament on a P-36, they had the capacity for .50 nose guns, so presumably that could have been done again. Two .50 nose guns and four .30 wing guns had been sufficient for the Tomahawk subtype of the P-40.

 

[Wild_Bill_Kelso]

Said with the hindsight of knowing what had happened. They would not have known that at the time an order would have been put. The Hurricane was a plenty good fighter in the right hands in the right conditions in 1940/1941. British losses in Singapore were down to a lot of mitigating factors, the performance aspect of the type wasn't necessarily a factor in its failure as a fighter in theatre. The British were up against superior numbers, they had little support, no radar warning etc etc. Even the best fighters in the world would have suffered losses in theatre and would not have prevented Japan's subjugation of Singapore.

I agree this is all based on the benefit of hindsight, and I also agree that little could probably have been done about Singapore, a similar thing happened with the P-40s and Buffaloes a Java and Malaya, and P-40s in the Philippines (and Pearl Harbor). But with the Hurricane they never did seem to work out how to use it effectively against the Japanese. They didn't do so well in Ceylon or later on in Burma, comparatively.

They were, but not all of them, some were from British lots and had British serials. From March 1942 the RAAF received a stream of them through every month that year. According to the books, 153 aircraft from the British Defence Aid DA-3 contract were shipped to Australia from San Francisco beginning in March 1942, of which 14 were sunk on route and were not replaced.

I can tell you that of the first few hundred P-40s the Australians got, they lost about half of them in training accidents and crashes during transportation to the front. The pilots had no time on them before they were thrown into the breech. Same thing happened to the US 49th FG initially as well.

 

[Wild_Bill_Kelso]

I don't know what the fascination about a radial engine Whirlwind is.

In this context it would be a very poor choice, since it would have to be re-engineered for the R-1830s, which would set back production significantly.

Well, from my point of view only with an eye toward making them in Australia, since they had the R-1830s there.

The Glosters were never put into production and are often referred to by the Air Ministry specification number. So they are the Glost F.5/34 and F.9/37.

In your list the only really viable option, IMO, is the P-36/Hawk 75.

The Gloster F.9/37 used the Taurus, just as the Beaufort did. Converting to R-1830s would be OK, but the aircraft was not production ready.

I think this could have had enormous potential since after all, they were making the Beauforts right? Assuming they got lucky with teething issues.

The Gloster F.5/34 was probably passed its time.

The Brewster Buffalo? Possible as an alternative, but would you want a Buffalo over a P-36?

Maybe? The Finns sure liked it. Probably needed some modifications (weight savings) but Geoff Fiskin did pretty well in one too..

The Beaufighter started out as a fighter based on Beaufort bits, but really only retained the wing? It also had the larger, more powerful Hercules, so fitting them with R-1830s would not have resulted in a very good aircraft.

Seems like if they could make Beauforts they may have been able to make Beaufighters, and Beaufighters were certainly very useful in the Pacific

Don't know much about the Fokker D.XXI. Its performance seems lower, and it was designed around a less powerful engine. How much extra work needed to get the R-1830 to fit and work with the airframe?

It's almost exactly the same size and shape as a P-36, and partly wood and stretched fabric construction. The only downside of those is fixed undercarriage. It did 290 mph with an 830 hp Mercury engine so presumably, it would be a bit faster with the 1830. They were actually designed for the Far East and the export market, so they were made to be simple to maintain. This is another one that the Finns did pretty well with, even against the Germans. It also apparently had the capacity for 20mm guns though they were not fitted.

The Seversky P-35 was a bit down on performance compared to the P-36A (R-1830). It had better armament, though.

yes it also had the issue with the 'wet wings'

The Italians I also do not know much about.

The Re 2000 first flew in 1939, giving about a year to get it into production and a licence deal done with Australia. Probably not going to happen, since the prototype had some issues.

The FIAT G.50 was in production, and service, before WW2. From that point of view it was possible. It was another light aircraft with a small engine, though a prototype was made with an engine of similar power to the R-1830.

Both Re 2000 and Fiat G.50 were pretty good, if not fantastic, and I think the British actually expressed some interest in the Re 2000 - they actually sent a commission to look at them in 1939 and almost bought 300 of them. If they had done the deal a few months earlier they may have got the license and plans etc..

I'm not sure which in the list have much in the way of development potential.

None were world beaters, except maybe the Gloster F9, but most had more potential as a fighter than an Na-16 though probably!

 

[Wild_Bill_Kelso]

Agreed. Really this discussion should be trying to justify why not the P-36, since it's the obvious choice.

And once the Pratt & Whitney Twin Wasp R-1830-76, featuring a two-stage supercharger is available the RAAF can field a P-36 Super Hawk, the best P-36 variant never made.

P-36 looks like the obvious candidate to me as well, but one downside is that due to stressed-skin construction, it may have been harder for local industry to manufacture, possibly.

Isn't that the engine that powered the Wildcat at Midway in June 1942? It seemed up to the task.

I think so!

 

[Wild_Bill_Kelso]

The F4F Wildcat entered service in mid-1940. June 1942 saw production of the 2,000hp R-2800 powered Vought F4U Corsair starting, followed by the similarly powered Grumman F6F Hellcat in July. While the F4F may have been "up to the task" at Midway it was clearly aready seen as past it.

Nevertheless, the F4F was the fighter which bore the brunt of the fighting in the Pacific, along with P-40 and P-39, through the tipping point of the war almost to the end of 1943. F4U came in slowly in small numbers, a long with an even smaller number of P-38s, F6F wasn't really in the field until the end of 43 (first combat, against a flying boat, was in September, but the first real engagement was 23 November at Tarawa).

So the Wildcat wasn't ideal, clearly, but it was 'good enough', and a land based version without folding wings etc. could be a bit lighter (i.e. more like the more popular F4F-3 than the F-4). Remove folding wings and all the naval gear... it's a good candidate as a ground based fighter for the early war.

This might in fact be another option for the Australians in this 'what if' scenario, how about an Aussie Martlet?

 

[Admiral Beez]

This might in fact be another option for the Australians in this 'what if' scenario, how about an Aussie Martlet?

This or the P-36 are the best picks. What we don't have is the start date for this project. If it's 1938-39 then P-36, but 1939-1940 the Martlet.