Admiral Beez
Banned
What would Japan have built if the spec that called for the A6M required self sealing tanks, good pilot protection, strong firepower AND competitive performance? Obviously a better engine is the starting point.
A6M spec calls for high protection and heavy firepower
- Thread starter Admiral Beez
- Start date
Better engine as starting point and for that you need a POD many years in the past where the Japanese aircraft engine industry is significantly better than it was OTL. This is something they struggled with throughout the war, they even had trouble license producing (and maintaining in the field) German engines.
Without that, you get an overweight and underpowered fighter that makes a Brewster Buffalo look like an F-16 by comparison...
marathag
Banned
They had that engine, the Kasai, first used the the G4M Betty. It was first run in 1938. It was large displacement, R-2600 class. 1500 HP for takeoff in early trim
It weighed about 400 pounds more than the Sakae.
Think of the difference between Wildcat and the early design for the Hellcat, before that was redesigned for the larger R-2800 from the R-2600 powered XF6F-1
A higher powered Zero with more guns and armor with stronger structure can be seen with the A6M5b, Model 52 Otsu
There is no reaso this couldn't have been built in 1940, other than the IJNAF knowing that's what they needed
Admiral Beez
Banned
This latter point is probably the best place to start. Get Japan buying German-produced BMW 801 in late 1939, shipped via Russia to Japan. License-production begins in spring 1940. By 1941, get the foibles worked out in Japanese production.
The Mitsubishi Kasei was the Japanese equivalent, only they had it first, and in time.
marathag
Banned
Heh. Need this for a TL
Mitsubishi sells the license for the Kasei to the Germans in 1939, a _working_ 1500HP class engine.
The Kasei is as useful as it goes. Vs. the initial Zuisei it provides twice the power even with initial versions - 1500 HP for take off, 1360 HP at 13500 ft. Not too big at 52.7in diameter, and light (1600 lbs) for the power it was making. The BMW 801 is another 500 lbs heavier, and in earlier iterations not a paragon of reliability that is essential for Japanese because of long distance tasks expected. The Kasei-powered G4M was among the participants in the sinking of POW and Repulse, so the time-line fits here.
Later versions went to 1800+ HP for take off, 1280 HP at 19700 ft, or 1520/1560 HP at 18000 ft (US called this 'military rating' in ww2 docs), supposedly got the water injection (adds 200-300 HP between ~18000 ft and sea level, but not for take off) so the engine is very much competitive as the war continues. Weight increase was barely 100 lbs for the versions without extended prop shafts.
Basically - Japan have had a very competitive big radial well before Pearl Harbor, just didn't use it to the maximum.
Later versions went to 1800+ HP for take off, 1280 HP at 19700 ft, or 1520/1560 HP at 18000 ft (US called this 'military rating' in ww2 docs), supposedly got the water injection (adds 200-300 HP between ~18000 ft and sea level, but not for take off) so the engine is very much competitive as the war continues. Weight increase was barely 100 lbs for the versions without extended prop shafts.
Basically - Japan have had a very competitive big radial well before Pearl Harbor, just didn't use it to the maximum.
If I may: 1360 HP at 13500 ft, 'military power' in 1941, per US/TAIC data; 'war emergency' rating estimated by TAIC at 1470 HP at 12800 ft. This is for Navy model of the Kasei in 1941.
Army model of the Kasei, called Ha 101, was better at altitude, trading a bit of take off power: 1360 HP at 15100 ft 'military power'; 1470 HP at 14100 ft 'war emergency power', 1490 HP for take off.
From Wikipedia:
"Front line units from mid-1940 were equipped with the Ki-21-IIa ("Army Type 97 Heavy Bomber Model 2A") with the more powerful 1,118 kW (1,500 hp) Mitsubishi Ha-101 air-cooled engines and larger horizontal tail surfaces."
BMW 801C (1/3rd heavier, 2in smaller diameter, better exhaust system, 'squished' intake, questionable reliability): 1361 HP (1380 PS) at 15100 ft, 3 min emergency rating; 1292 HP (1310 PS) at 14440 ft; 1540 HP (1560 PS) for take off.
Reason why I state HP as power unit for Japanese engines is that I'm reading it from TAIC technical report, where from also came US terms of 'military power' and 'war emergency power'.
My idea is to build an 18 cylinder Zuisei, which i called Ryusei, and/or an earlier Homare (which is an 18 cylinder Sakae). Very small diameter which helps in a fighter, this being Kasei's biggest drawback. The early Ryusei and Homare should be good for 1400-1500HP, later model with MW-50 boost will go to 1700-1800HP. This ATL Zero might be delayed a bit though, but could still enter service in 1941.
But really to get to this ATL Zeros things has to start happening earlier, something must make the japanese go for bigger engines and more firepower in their fighters. How about an 1937 A5M on steroids first, with 4 MGs, a 840HP Hikari engine which will be replaced as soon as possible (1939) by a 950 HP Sakae or 1000HP Kinsei, and maybe even a retractable gear. By 1937 almost every big aeronautical power was building retractable gear fighters, including the least powerful of them, Italy. I see no reason why Japan couldn't too, with an apropiate POD of course.
This A5M on steroids surely could stay in the ring with the F4F and F2A almost as good as the OTL Zero did. On the other hand, this ATL A6M would rip the F4F to pieces (and the P-40, P-39, Hurricane etc., only the P-38 and F4U would finally be able to counter it), however one thing it will lack as said above would be range. But with drop tanks probably one can get 400-450 nm out of it, still very good.
And while at it, what the hell, let's have some Ki-12, Ki-27 and Ki-43 on steroids too.
But really to get to this ATL Zeros things has to start happening earlier, something must make the japanese go for bigger engines and more firepower in their fighters. How about an 1937 A5M on steroids first, with 4 MGs, a 840HP Hikari engine which will be replaced as soon as possible (1939) by a 950 HP Sakae or 1000HP Kinsei, and maybe even a retractable gear. By 1937 almost every big aeronautical power was building retractable gear fighters, including the least powerful of them, Italy. I see no reason why Japan couldn't too, with an apropiate POD of course.
This A5M on steroids surely could stay in the ring with the F4F and F2A almost as good as the OTL Zero did. On the other hand, this ATL A6M would rip the F4F to pieces (and the P-40, P-39, Hurricane etc., only the P-38 and F4U would finally be able to counter it), however one thing it will lack as said above would be range. But with drop tanks probably one can get 400-450 nm out of it, still very good.
And while at it, what the hell, let's have some Ki-12, Ki-27 and Ki-43 on steroids too.
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marathag
Banned
Later mark Zeros with Self sealing tanks carried more fuel than the early.
They had additional wing tanks.
Now they didn't have as much range, being heavier from armor plate, stronger structure and more guns and ammo.
But the A6M5 Model 52C still had 1300 mile range with drop tank, vs 1900.
Hellcat had 945 miles, Wildcat 830.
Later Zero got better range, and isn't a flaming deathtrap anymore
Later Zeros (starting from A6M5c) were however badly underpowered and outclassed by the opposition. What would have alleviated the lack of power would have been the 1560HP Kinsei-62, but we know that story.
So basically it seems this ATL Zero would have been something like OTL A6M8, but in 1941.
So basically it seems this ATL Zero would have been something like OTL A6M8, but in 1941.
marathag
Banned
They had everything they needed to make a fighter like that in 1941, except the vision to do so
Admiral Beez
Banned
Perhaps we need a volunteer Japanese contingent in the Luftwaffe for the Battle of Britain. That will teach them the importance of robust, survivable aircraft.
Japan was apparently considering license production of the https://en.wikipedia.org/wiki/Gnome-Rhône_Mistral_Major
Maybe the Japanese can get their hands on these https://en.wikipedia.org/wiki/SNECMA_14R
The 14R powered the Bloch MB-157 was tested by the Germans, who found it to be very favourable.
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Obergruppenführer Smith
Banned
Hold it everyone. Given that only 8,569 Kasei were manufactured during 1941-1945 compared to 33,233 Sakae, could it be that Kasei was more difficult to manufacture, or there just wasn't the capacity for more production?
marathag
Banned
It was mostly a bomber engine, and since it had very good reliability, apparently wasn't more difficult, unlike Aichi and Kawasaki making the DB-601. Only a few thousand planes were built that needed it.
If the Kasei is used for the main fighter, yes, Mitsubishi will be making more.
thorr97
Banned
Well, unless you engineered some pretty massive cultural changes among the IJA and IJN, what you'd have gotten was an absolute dog of an airplane that was severely underpowered for what the spec had loaded on to it. At least in 1939. Maneuverability and range were THE main criteria for the air forces of Japan. Stuffing the heavier engine into that airframe in '39 might've made it faster without the additional equipment but with it? The maneuverability would've suffered and so to the range. Neither the Imperial Japanese Army nor the Navy would've accepted that. At least not in '39 as that was before the limits of the lightweight and unarmored Zero had been revealed in combat.