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

[Glider]

You mean the F5? Or the Jet...? F5 was actually the original inspiration for this thread topic. I thin it's interesting to consider if they had made a few hundred of those...

The Bristol F5/34. It had a good performance with an 840hp engine, and I am as sure as I can be that there was some growth potential in it

 

[Wild_Bill_Kelso]

The Bristol F5/34. It had a good performance with an 840hp engine, and I am as sure as I can be that there was some growth potential in it

I think so too!

 

[EwenS]

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.

1944 only just!

Only about 90-100 P-36 Mohawks reached Burma for use by the RAF after modification. About 35 were lost before being withdrawn. Only 3 front line RAF squadrons used the Mohawk with the last being withdrawn during January 1944.
5 - Dec 1941 to June 1943 (alongside biplane Audax until Sept 1942) replaced by Hurricane IIc
146 - March - April 1942 received a small number which it passed to 5 squadron and were replaced by Buffaloes and then a month later Hurricane IIb
155 - Aug 1942 to Jan 1944 when replaced by Spitfire VIII

 

[Admiral Beez]

The Bristol F5/34. It had a good performance with an 840hp engine, and I am as sure as I can be that there was some growth potential in it

There is no Bristol F5/34. Perhaps you mean the Gloster?

There is the Bristol Type 133 and Type 146. The latter may be a contender for the RAAF.

 

[Shortround6]

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

In 1939, when this would have had to start the P-36 did NOT have a proven track record in France. In fact the P-36 and the Hawk had a rather shaky track record of landing accidents, bent, buckled wing and fuselage skinning and wings that needed replacing. Some may have been do to training?
Again the engine, or rather which version of the R-1830 is in question. The US was specifying 100/100 fuel although they didn't call it that in late 1939 and 1940. They were making R-1830s that ran on 87 or 90 octane fuel for other countries, there actually wasn't much difference in the engines.
Interestingly with the better fuel they were often allowed to make a bit more power at lower altitudes but if you are building a fighter for use at 15,000ft do you really care if the engine makes 900hp at 10,000ft using 91/93 octane or if it makes 1050hp at 6500ft on 100 octane? By the time you get to 10,000ft the 1050hp engine will be down by at least 70hp.
The Australians aren't going to know in 1939-1940 but the two .50 cal guns in the Fuselage were almost worthless for over 1/2 of 1941.

I have having trouble figuring out were these superpower R-1830s were supposed to come from. The R-1830 used a two speed supercharger to get 1200hp for take-off. Different models were good for 3700ft to 4900ft military power for 1200hp.
In high gear power could be 1050hp at 13,100 to 1000hp at 14,500ft.
Now compare to the Tomahawk. About the same power at the same altitude (not going to argue about 30-40hp) BUT, The radial engine has a lot more drag and has little or no exhaust thrust in the engine installations of 1940-42 (Fw 190 aside).

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.

Again, see French and American problems with the radial engine Curtiss fighters and that is with less "stuff" (like SS tanks)

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

When did they have R-1830s? Not in 1939 and not in 1940.

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

The Finns, and their Buffaloes were a special case. The Buffaloes, through their history, used 3 different versions of the Wright R-1820 engine. One reason the Finns had such light Buffaloes is because the version of the R-1820 they used (were given, they didn't have a choice) didn't use a reduction gear on the prop and used a two blade propeller or rather small diameter. It used an aluminum crankcase, not steel like the R-1820s used. The Finns got a steel plate behind the pilots seat but no BP glass and no fuel tank protection. Once you stick in an engine that weighs several hundred pounds more you just may need the heavier landing gear and a few structural reinforcements the later Buffaloes got.

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.

Yea, let's see how that works, yank an engine of roughly 1000lbs and replace with an engine that weighs about 1490lbs. Of course you can use the prop designed for 840hp to save weight There were some Fokker XXIs built with P&W engines but they were R-1535s, not R-1830s.
The Mercury did have one advantage in that if gave 840hp at over 14,000ft so it actually wasn't that far off what the R-1830 gave. Certainly not the 840hp vs 1200hp some people are expecting.

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.

And again nobody looks at the specs or looks at the installation requirements. The P&W test hack that flew with the two stage R-1830 after they yanked the Allison -33 lost the cowl guns. The entire fuselage in front of the windscreen was changed. they were routinely flying the aircraft at 7,100lbs with no guns, no armor, plain tanks and several other items left out.
It was estimated that service weight would have been 8300lbs but the armament is not specified.
AN 8300lb P-36 is one heck of a P-36.

 

[Wild_Bill_Kelso]

There is no Bristol F5/34. Perhaps you mean the Gloster?

There is the Bristol Type 133 and Type 146. The latter may be a contender for the RAAF.

Woah, that 133 is a weird one!

 

[Glider]

There is no Bristol F5/34. Perhaps you mean the Gloster?

There is the Bristol Type 133 and Type 146. The latter may be a contender for the RAAF.

It's been a long day

 

[Admiral Beez]

It's been a long day

My fantasy for the Gloster F5/34 is that the prototype, drawings and any jigs somehow in early 1937 gets sent to Elsie MacGill at CC&F, where a supply chain for Wright and P&W engines already exists. By early 1939, instead of Hurricanes (Gloster is a division of Hawker Siddeley Aircraft, Ltd.) the Gloster Loon (or other Canadian bird, maybe the Bufflehead?) takes flight with a US engine replacing the originally intended Bristol Perseus. Thus begat the Empire fighter program, with production beginning at CAC in early 1940 and kit assembly HIL by early 1941.

We'll need MacGill to work her magic to get either the Cyclone or Twin Wasp to hit into the Loon's frame. Then Australia can source the same engine.

Bristol Perseus
Length: 49 in (1,245 mm)
Diameter: 55.3 in (1,405 mm)
Dry weight: 1,025 lb (465 kg)

Wright R-1820 Cyclone
Length: 47.76 in (1,213 mm)
Diameter: 54.25 in (1,378 mm)
Dry weight: 1,184 lb (537 kg)

Pratt & Whitney R-1830 Twin Wasp
Length: 59.06 in (1,500 mm)
Diameter: 48.03 in (1,220 mm)
Dry weight: 1,250 lb (570 kg)

 

[Shortround6]

It would help on these fantasy fighters if we weren't proposing fantasy engines to propel them.

The Figures for Pratt & Whitney R-1830 Twin-Wasp on Wiki are misleading at best.

A 1250lb Twin Wasp did exist, but it didn't make 1200hp. The 1200hp Twin Wasps went between around 1430lbs and over 1560lbs depending on model and supercharger.
The 1250lb versions seem to have been restricted to 2450rpm (instead of 2700rpm) and about 950hp.

I haven't even looked at Wiki for the R-1820 number as the number in the above post is way off.
1184lbs look about right for a R-1820-G series engine. But they were only good for 2200rpm and were good for 1000hp for take-off at best. They came with different supercharger gears and power at altitude varied with the gear ratio.
The R-1820-G100 series was good for about 1100hp from 2300-2350 rpm for take-off but went about 1260-1272lb depending on exact model. These were the engines in the the Buffaloes in between the Finnish ones and the later US Navy ones.
The F2A-2 and F2A-3 got R-1820-G200 the 1200hp take off engines at 2500rpm but they went around 1310-1320lbs.

The Wright engine used by the Canadians in the International Arms Smuggling deal during the Spanish Civil war was probably the R-1820F series engine and max rpm was 1950rpm and weight was around 910-940lbs for the direct drive engines and around 1040-1050lbs for the engines with reduction gears.

Now since the Mercury was giving about 840hp at 14,000ft using 87 octane fuel for a 1000lb engine in 1937-38 there was little point in the British or Canadians trying to come up with different engine installations until war was staring them in the face and considering the fact that both P & W and Wright had managed to come up with sufficiently powerful versions of their engines to make them alternatives instead of 2nd class engines. But please note that the 1200hp for take off R-1830 was almost 50% heavier than the Mercury and that the R-1820-G200 series of engines only showed up in March of 1939 and I don't know if they were on some sort of "secret" list. They didn't show up In Buffaloes until the F2A-2 model. They did show up in the Hawk 75 A-4 version just at the fall of France. The R-1820-G200 certainly worked in a number of other planes but the installation in the Hawk 75 was so bad that the French were repowering them with R-1830s (used ones) in 1943-44.

Just to finish off the R-1820 story Wildcat FM2 used the R-1820H engine which no parts at all with the G200 series. Like wise the G200 shared very little, if anything with the G100 and the G100 shared nothing with the G and show it went back to the R-1750 Cyclone.

 

[nuuumannn]

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.

Again, that's arguable, the Hurricane was kept in theatre in the CBI primarily as a ground attack aircraft and PR platform and in both roles it did better than is commonly appreciated. The RAF had Spitfires and Thunderbolts as fighters, so let's be clear, the Hurri wasn't primarily tasked with fighter duties once the better fighters were available, of course. Losses of pure ground attack assets can be expected. Its record as a tac recon platform are also misconstrued in theatre, it did quite well, according to reports.

 

[nuuumannn]

This is later in the war, of course, the first Hurricane units in the Defence of the region in late 1941 through 1942 and into 1943 were obviously fighter reinforcements and carried out fighter duties, but once the RAF regrouped and provided better fighter types in theatre, the Hurricanes were primarily ground attack, with IIcs and their four 20mm cannon and IId models with their two 40 mm cannon. Hurricanes were gradually replaced in the fighter role through 1943 onwards, night fighter Hurris in defence of Calcutta fitted with AI sets were replaced by Beaufighters in early 1944, while day fighter units replaced their Hurris with Spitfires and Thunderbolts.

All this activity and requisite losses helps explain why the British kept the Hurricane in production for as long as it did; it was very much an interim until something better came along, but the fighting in theatre was fierce and the logistics of replacing a type already in a heavy combat arena so far from home were difficult. Hurricanes put up a good fight and suffered losses against superior numbers and excellently trained enemy pilots, but they held the line for longer than they should have.

This is what author Robert Jackson said about the siege of Imphal:

"From the beginning of March until early August, during the battles for Kohima and Imphal, five Hurricanes were shot down by enemy fighters, sixteen by ground fire and thirteen others were lost through accidental and other causes. Fifteen more Hurricanes were damaged. Their achievement had been out of all proportion to the losses they sustained. Over the Imphal Velley, it had been the Dakotas that had kept the Army supplied and the Spitfires which had brought mastery of the air: but it had been the Hurricanes what had first of all blunted the spearhead of the Japanese advance, then slowed it down and finally stopped it altogether."

 

[nuuumannn]

Reading more about this, the issues that the RAF suffered in Singapore in late 1941 through 1942 continued in theatre through into late 1943. The Hurricane fighter units were hampered by a lack of ground support, no early warning and thus a lack of time to get to height to provide adequate defence against attack aircraft and high flying recon aircraft. The ground crews at these forward bases provided Herculean efforts to keep the Hurris serviceable in difficult conditions, but the aircraft proved a lot hardier and resistant to damage and easier to repair compared to the all-metal aircraft. Providing flight escort to Allied bombers, the Hurricanes stood their ground but suffered losses as expected against Ki-43s and so forth, but it wasn't all one way, the Hurricanes intercepting bombing raids caused losses to the Japanese, including among the escorts. This all took place in the Arakan region through March to May 1943, with the month of March being particularly successful for the Hurricane units in claiming enemy aircraft. That month, attack sorties by the newly arrived Hurricane IIcs and their four 20mm cannon proved very effective at keeping heads down.

It's riveting stuff.

 

[Wild_Bill_Kelso]

The thing was, they were able to make P-40s work quite well in the CBI, both in the fighter bomber and fighter role, whereas the Hurricanes took fairly extreme losses against Japanese fighters, and were also limited by their short range / endurance. They just didn't match up well for the Theater, IMO. I'd say the same thing for Blenheims. Beaufighters on the other hand, worked out quite well, and the Spit VIII, once it arrived, was also effective. I think Beauforts were pretty good too.

 

[Wild_Bill_Kelso]

It would help on these fantasy fighters if we weren't proposing fantasy engines to propel them.

The Figures for Pratt & Whitney R-1830 Twin-Wasp on Wiki are misleading at best.

A 1250lb Twin Wasp did exist, but it didn't make 1200hp. The 1200hp Twin Wasps went between around 1430lbs and over 1560lbs depending on model and supercharger.
The 1250lb versions seem to have been restricted to 2450rpm (instead of 2700rpm) and about 950hp.

I haven't even looked at Wiki for the R-1820 number as the number in the above post is way off.
1184lbs look about right for a R-1820-G series engine. But they were only good for 2200rpm and were good for 1000hp for take-off at best. They came with different supercharger gears and power at altitude varied with the gear ratio.
The R-1820-G100 series was good for about 1100hp from 2300-2350 rpm for take-off but went about 1260-1272lb depending on exact model. These were the engines in the the Buffaloes in between the Finnish ones and the later US Navy ones.
The F2A-2 and F2A-3 got R-1820-G200 the 1200hp take off engines at 2500rpm but they went around 1310-1320lbs.

The Wright engine used by the Canadians in the International Arms Smuggling deal during the Spanish Civil war was probably the R-1820F series engine and max rpm was 1950rpm and weight was around 910-940lbs for the direct drive engines and around 1040-1050lbs for the engines with reduction gears.

Now since the Mercury was giving about 840hp at 14,000ft using 87 octane fuel for a 1000lb engine in 1937-38 there was little point in the British or Canadians trying to come up with different engine installations until war was staring them in the face and considering the fact that both P & W and Wright had managed to come up with sufficiently powerful versions of their engines to make them alternatives instead of 2nd class engines. But please note that the 1200hp for take off R-1830 was almost 50% heavier than the Mercury and that the R-1820-G200 series of engines only showed up in March of 1939 and I don't know if they were on some sort of "secret" list. They didn't show up In Buffaloes until the F2A-2 model. They did show up in the Hawk 75 A-4 version just at the fall of France. The R-1820-G200 certainly worked in a number of other planes but the installation in the Hawk 75 was so bad that the French were repowering them with R-1830s (used ones) in 1943-44.

Just to finish off the R-1820 story Wildcat FM2 used the R-1820H engine which no parts at all with the G200 series. Like wise the G200 shared very little, if anything with the G100 and the G100 shared nothing with the G and show it went back to the R-1750 Cyclone.

These are quite interesting details, particularly about the F2A with the aluminum transmission case that you mentioned.

I don't think it matters so much which particular sub-type of R-1830 was used (or for that matter, an 1820 if they could build those in Australia). Production would have hard to start early but presumably they would have kept making changes including various engine subtypes (which would have depended not just on what was available, but what they could get licensing and support to produce).

The CAC produced Boomerangs right to the end of the war. If they had started with a P-36, an F4F / FM - or a Gloster F5, Re 2000 or D.XXI or whatever, they may have arrived at something more interesting by say, 1942 or 43.

Of course, this is a "What If" thread and it is indeed 100% powered by hindsight. I was just interested in exploring the possibilities.

 

[Wild_Bill_Kelso]

We could also talk about replacing the Woomera....

 

[Wild_Bill_Kelso]

In 1939, when this would have had to start the P-36 did NOT have a proven track record in France. In fact the P-36 and the Hawk had a rather shaky track record of landing accidents, bent, buckled wing and fuselage skinning and wings that needed replacing. Some may have been do to training?

That is true, but on the other hand the French had purchased quite a few P-36, as did the Dutch for their East Indies colonies, and I think Thailand bought some too? (not sure if the ones they used were captured or purchased) and that would be a pretty good reason for Australia to buy them.

The Finns, and their Buffaloes were a special case. The Buffaloes, through their history, used 3 different versions of the Wright R-1820 engine. One reason the Finns had such light Buffaloes is because the version of the R-1820 they used (were given, they didn't have a choice) didn't use a reduction gear on the prop and used a two blade propeller or rather small diameter. It used an aluminum crankcase, not steel like the R-1820s used. The Finns got a steel plate behind the pilots seat but no BP glass and no fuel tank protection. Once you stick in an engine that weighs several hundred pounds more you just may need the heavier landing gear and a few structural reinforcements the later Buffaloes got.

Sounds like the success of the F2A would definitely hinge on which type they got, though based on the RAF experiences with them, I'd say the F2A may have still been better or had more potential than a Boomerang.

 

[tomo pauk]

The Fokker D.XXI might've been a half-decent choice. Engine - either the 'original' Mk.VIII with some 100 oct fuel experimenting in overboosting, or the Mk.XV (fully-rated for 100 oct fuel, making almost 1000 HP at 8000-9000 ft). A drop tank is a must.
People in Finland retrofitted their two examples with retractble U/C, average speed maximum went to ~10 mph for those.
Mercury engines will be easier to get for Aussies than some of more advanced engines, like the 1200 HP versions of the R-1830 or R-1820.
The D.XXI is available early enough - timing means a lot.

 

[Wild_Bill_Kelso]

The Fokker D.XXI might've been a half-decent choice. Engine - either the 'original' Mk.VIII with some 100 oct fuel experimenting in overboosting, or the Mk.XV (fully-rated for 100 oct fuel, making almost 1000 HP at 8000-9000 ft). A drop tank is a must.
People in Finland retrofitted their two examples with retractble U/C, average speed maximum went to ~10 mph for those.
Mercury engines will be easier to get for Aussies than some of more advanced engines, like the 1200 HP versions of the R-1830 or R-1820.
The D.XXI is available early enough - timing means a lot.

Plus partly fabric and wood construction would probably be easier to make. I think even with the fixed undercarriage it might have had some use. Probably less pilot accidents in takeoff and landing for one thing.

 

[Shortround6]

Mercury engines will be easier to get for Aussies than some of more advanced engines, like the
1200 HP versions of the R-1830 or R-1820.

The D.XXI is available early enough - timing means a lot.

And this is part of the argument.

A lot of people seem to want the aircraft construction to start early. Like 1939 it order for the factories to come on line in 1941 in order to actually have a useable number of airplanes in Jan 1942. But the 1200hp engines don't exist in 1939 (or barely) and are scarce even in 1940.

ALL of the export Buffaloes in 1940/early 41 got 1100hp versions of the Cyclone.
Heck the USN was loading 1000hp Cyclones into SBDs in 1942. Granted a lot of aircraft were getting the 1200hp versions.

Martin Marylanders got R-1830s with 1050hp for take-off and 900hp at 12,000ft in the MK I version (Those Mercuries don't look so bad) and went to about 1000hp at 12,500ft in the MK IIs.
A lot is going to depend on the fuel. The US was making engines for American 100 octane fuel in late 1938 and into 1939/40 for the US Military and for the commercial airlines that wanted to use it. They were also making engines that would run on 87 octane or 90 octane for countries that didn't have 100 octane or countries/ companies that didn't want to pay for 100 octane fuel. As I have said many times before the British fuel that the British were dumping into Spitfires/ Hurricanes/ Bristol Blenheim's etc in 1939/40 was not the same fuel. It was about 15-20 points higher on the Performance number scale than US 100 octane fuel. The US fuel was a lot better than 87 octane but it wasn't what the British were using.

Now for the Australians, Chinese, Indians and whoever else in 1939-40. What kind of fuel are you going to get in the future and how much?

Now for the Fokker XXI here is a picture on skis.

Here is another one

Note the different engine, the upper plane used the P & W R-1535.

Now the Mercury engined planes went about 4300lbs fully loaded with their 1000lb engine.
Thinking you can substitute 1300-1500lb engines with bigger props without a lot rework is probably not going to go well.
Also please note that just about all of these planes used four rifle caliber machine guns for 1/2 the fire power of a Hurricane I.
Which means you need more aircraft (and pilots) to get similar firepower into the sky to combat incoming air raids.

 

[GTX]

I strongly suggest a read of Sir Lawrence Wackett's autobiography "Aircraft Pioneer: an Autobiography" for the background into why the North American NA-16 was the basis for CAC's aircraft production/development. This led to the CAC Wirraway and later the CAC Boomerang. The 1936 overseas evaluation mission to inspect aircraft production in Europe, Britain, and the United States visited and considered many of the manufacturers of the alternate aircraft types suggested here and North Nmerican came out in front as the best choice for a number of reason.