Kawasaki making something else instead of Ki-45?

[Just Schmidt]

Japanese, or at least their Army air service, were not in the need for night fighters until late 1944? Lack of the radar certainly makes any Japanese NF severely under-performing in it's task. As a fighter bomber - looks like there were no bombs or rockets carried ever? Just one cannon (neither of the types installed in the nose were great) for two engines seems like a waste for me*. Other people - including Japanese - used just one engine on a fighter that carried 2 cannons in 1941-43 (or 1, or 4 cannons in Europe). A smaller vessel (from a 1500-2000 t destroyer down?) was probably more afraid of 6 gun HMG battery on a P-40 than it will be afraid of a Ki-45.

* late in the war, it carried another pair of cannons in a 'schreage musik' layout

I should have said ground attack, though fitting bombs should be possible in a what if. yes, after all I too want to have my cake and to eat it.

As so often I'm weeks away from my books, but i do believe its career as night fighter started before the campaign against the Japanese homeland. You're probably right that it wasn't outstanding in very many roles, but still I think that in several it was better than anything Japan actually did put into service, at least until the Ki-102 which was itself a development of it.

A Fw-187- like one-seater is an intriguing idea, but possibly one more overly specialized Japanese aircraft? As for single engined fighters I like your previous idea/thread of up-prioritizing the Ki-44. But until more power becomes available, I see little point in additionally developing anything with a sub-1500 hp radial. Of course a slightly earlier Ki-44 I, if that is doable(?), could fit the bill here, though probably not on a 1050 hp engine.

 

[tomo pauk]

A Fw-187- like one-seater is an intriguing idea, but possibly one more overly specialized Japanese aircraft? As for single engined fighters I like your previous idea/thread of up-prioritizing the Ki-44. But until more power becomes available, I see little point in additionally developing anything with a sub-1500 hp radial. Of course a slightly earlier Ki-44 I, if that is doable(?), could fit the bill here, though probably not on a 1050 hp engine.

Whether Japanese loved it or not (probably not), they mostly have in volume production the sub-1500 HP radials until water/alcohol injection was adopted to the big Kasei - talk mid 1943? A reason why I'm hyping the Ki-44 and Ki-60 is that those two were with a much smaller wing than Ki-43 and Ki-61, so the drag % of wing was smaller on the former two types. A 1050 HP @ 4km power provided by engine installed on Ki-44 or Ki-60 airframe might result with ~550 km/h? (Ki-44-I did 580 km/h with engine making 1260 HP @ 3.7 km). Ki-43-I being good for 500 km/h, and Ki-43-II doing 530+- km/h from late 1942 on, depending on exhaust stack configuration.

 

[Just Schmidt]

Whether Japanese loved it or not (probably not), they mostly have in volume production the sub-1500 HP radials until water/alcohol injection was adopted to the big Kasei - talk mid 1943? A reason why I'm hyping the Ki-44 and Ki-60 is that those two were with a much smaller wing than Ki-43 and Ki-61, so the drag % of wing was smaller on the former two types. A 1050 HP @ 4km power provided by engine installed on Ki-44 or Ki-60 airframe might result with ~550 km/h? (Ki-44-I did 580 km/h with engine making 1260 HP @ 3.7 km). Ki-43-I being good for 500 km/h, and Ki-43-II doing 530+- km/h from late 1942 on, depending on exhaust stack configuration.

Again lacking my own reference works, i have to rely on wiki, which does seem to agree in this case. maybe because they are cited.

Anyway the Ki-60, apart from having what was considered less than desired handling, performed worse than the later Ki-61 (Quted as 560 km/h). It is quite possible that aspect could have been improved on, but as is, I doubt very much it would reach 550 km/h with 1050 hp radial. What the Ki-44 could have achieved is another matter, but would it be enough above 530 km/h to justify another short term solution in addition to the historical Ki-44 I, which armament besides seem adequate for its time?

I find myself wishing I really know more about the early development of the Ki-44.

 

[tomo pauk]

Anyway the Ki-60, apart from having what was considered less than desired handling, performed worse than the later Ki-61 (Quted as 560 km/h). It is quite possible that aspect could have been improved on, but as is, I doubt very much it would reach 550 km/h with 1050 hp radial. What the Ki-44 could have achieved is another matter, but would it be enough above 530 km/h to justify another short term solution in addition to the historical Ki-44 I, which armament besides seem adequate for its time?

I myself consider Ki-44 as an adequate fighter for it's time. Problem was that IJA (IJN problems are for another thread, and boy does it have food for thought) air service have had Ki-27s in service through whole of 1942, and Ki-43 was with sigificant shortcomings itself. Main problem with Ki-44 was it's short production run - it was phased out in 1944, while Ki-43 was still being produced in August 1945 - and thus relatively small numbers available. So the new source of better fighters is not an addition to the Ki-44 force, it would've make possible to get rid of the Ki-27 ASAP, replace the non-produced Ki-45 as per this thread thus saving a lot of war material, as well as fuel when inservice, having a ready replacement for the Ki-43 etc.

Kawasaki making a good 1-engined fighter already by late 1941 is not a short-term solution. As never versions of engines are available it's performance and combat capabilities can be improving. Eg. swapping the earlier Kinsei type (1050 HP at 4 km; 'History of Mitsubishi engines' gives 1070 HP at 4.3km) for the later type (Ha 112 per Army nomenclature; 1100 HP at 6.2 km) is an improvement, as is the Ha-112-II as installed on the Ki-100 (1250 HP at 6 km). More power between SL and 5 km was achieved via usage of water-alcohol injection, as on the Ki-46-III. More engine power means that addition of firepower and protection does not hurt the performance.

Ki-60's handling was influenced by it's high wing-loading, in the time Japanese preferred low wing loading that gave better maneuverability. A radial of 560 kg (= Kinsei that makes 1050-1070 HP at 4-4.2 km) will shave some weight vs. the 680 kg Ha-40/DB-601 + 150-200 kg of the weight of the cooling system, ie. around 300 kg less.

 

[Schweik]

The KI-45 was in keeping with the worldview idea of "heavy fighter" in the 1930's. When it was first introduced, it had impressive speed and range.
The KI-45 was actually better than the Nakajima's J1N, too.

Mitsubishi's KI-46 was very successful in it's early role and would have been eclipsed by the KI-70.

Ki-45 kinda gets a little too much bad press IMO, it didn't work out as a daytime air-superiority / escort fighter but the aircraft had a second act it ended up in a niche kind of similar to a Beaufighter. They did pretty well in ground attack and especially, anti-shipping, and had some success as a night fighter too. They also used it effectively as a bomber killer a couple of times in the South Pacific.

Should have been replaced by something faster (ala Ki - 102) a lot sooner, but it did seem to help the Japanese war effort.

 

[Shortround6]

A possible reason for the Ki-45s poor showing is the rather crappy armament.

One 20mm cannon about 3/4s as effective as a Hispano and two Ho 103 machine guns is hardly strong armament even in 1942.
Ability to inflict significant damage on bombers in a single firing pass is well below western standards.

Some books claim the 20mm was fed by a 50 round drum and list 100 rounds for the ammo capacity (one spare drum?)

Some planes replaced the 20mm with a hand fed 37mm gun.
Later planes did get an automatic 37mm but it was slightly below the P-39s 37 mm in performance.

 

[Schweik]

I don't know how much of each variant were produced, but the original ki-45 had two 12.7mm mg and 1 x 20mm cannon, which isn't bad considering all that is concentrated in the nose. I know they had some problems with their 12.7mm ammunition early on, which may have affected it badly. There was the version with the 37mm tank gun which was kind of a gimmick I agree (though I guess it had a role against heavy bombers and ships) and then they had the version with the automatic 37mm ala P-39 which you mentioned, which I think is not a bad main gun for a heavy fighter, and then the Schrage Musik cannons for the night fighter version.

How much improvement would they have had from the Ki-45 if they ditched the rear gunner and position? It seems like it was just under the kind of performance that might have made it effective. Could they have gotten another 20 mph out of it?

 

[tomo pauk]

I don't know how much of each variant were produced, but the original ki-45 had two 12.7mm mg and 1 x 20mm cannon, which isn't bad considering all that is concentrated in the nose. I know they had some problems with their 12.7mm ammunition early on, which may have affected it badly.

We can compare other people's firepower with just one engine investment in the late 1941, that have cannon armament. British have 2 cannons on Spitfire + 4 LMGs, while Hurricane is to receive 4 cannons. Germans have 1 cannon + 2 LMGs on the Bf 109 (criticized by Galland and the like, later to get gondola cannons to remedy the firepower weakness), while the Fw 190A2 has 4 cannons + 2 LMGs. Soviets have one cannon + 2 LMGs on M-105 powered fighters. Zero has two cannons instaled.
Yes, Ki-45 has also HMGs in the nose, however the rate of fire of the cannon is much lower than what Euros were installing (ie. 300-400 rd/min for the Ho-3 vs. 600-800 rd/min for European cannons). Ammo count is also nothing to get excited, 50 rd drum vs. belt-feed for the foreign competition. Yes, shells were powerful, ballpark of the Hispano or the 20mm Mine shell. All saidl, not much of firepower for such investment.

Had the Japanese came out with a 2-engined fighter that sports 2 cannons + 2 HMGs at least, while making perhaps 370 mph in 1941 (not impossible with Japanese engines of the day), people would've certainly held the said fighter in greater regard. OTOH, a Ki-44 with a tad bigger wing would've probably do that on just one engine, with major benefits in numbers produced and fuel usage vs. the Ki-45.

 

[Just Schmidt]

I myself consider Ki-44 as an adequate fighter for it's time. Problem was that IJA (IJN problems are for another thread, and boy does it have food for thought) air service have had Ki-27s in service through whole of 1942, and Ki-43 was with sigificant shortcomings itself. Main problem with Ki-44 was it's short production run - it was phased out in 1944, while Ki-43 was still being produced in August 1945 - and thus relatively small numbers available. So the new source of better fighters is not an addition to the Ki-44 force, it would've make possible to get rid of the Ki-27 ASAP, replace the non-produced Ki-45 as per this thread thus saving a lot of war material, as well as fuel when inservice, having a ready replacement for the Ki-43 etc.

Kawasaki making a good 1-engined fighter already by late 1941 is not a short-term solution. As never versions of engines are available it's performance and combat capabilities can be improving. Eg. swapping the earlier Kinsei type (1050 HP at 4 km; 'History of Mitsubishi engines' gives 1070 HP at 4.3km) for the later type (Ha 112 per Army nomenclature; 1100 HP at 6.2 km) is an improvement, as is the Ha-112-II as installed on the Ki-100 (1250 HP at 6 km). More power between SL and 5 km was achieved via usage of water-alcohol injection, as on the Ki-46-III. More engine power means that addition of firepower and protection does not hurt the performance.

Ki-60's handling was influenced by it's high wing-loading, in the time Japanese preferred low wing loading that gave better maneuverability. A radial of 560 kg (= Kinsei that makes 1050-1070 HP at 4-4.2 km) will shave some weight vs. the 680 kg Ha-40/DB-601 + 150-200 kg of the weight of the cooling system, ie. around 300 kg less.

One month late I finally got a chance to consult my book.

First i agree that Ki-44 was pretty good mid war, with the caveat that it could use heavier armament earlier. i'm not certain that the IJAAF can make do with it as their only front line fighter until the Ki-84 shows up.

Kawasaki making a good fighter earlier than historically may prove problematic. The Ki-60 seem not to have suffered only from manouverability issues on account of its high wing loading. For the first protoype: "The aircraft displayed some lateral instability, excessively heavy control and poor control response, it demanded an unacceptable long take off run in normal loaded condition; its spinning characteristics were considered 'dangerous'; its stalling speed was extremely high" Green, William and Swanborough,Gordon: Japanese army fighters: part 1 Macdonald and Janes 1976: p20. Speed for the prototype was only 548 km/h, raised to 560 in the subsequent prototypes with 5000 meters being reached in six minutes. No significant improvement in handling was present, Ibid.

It's questionable if a radial would in itself have cured that problem, and unless it gave more power performance would suffer. Eventually the Ki-61 emerged as the 'fixed' Ki-60 so I see little chance of achieving anything wortwhile until the historicallyKi-100 becomes a possibility, granted that could probably have happened well before 45.

As for the Ki-46 it had the slow rate of climb and manouverability shortcomings commented on by others. Actually a study by the Army Aerotechnical Research Institute shelwed a projected fighter adaption in summer 1943 on account of these problems. furthermore its structure (apparently in the eventual service model), proved insufficiently sturdy for absorbing combat damage, ibid 51f.

I do not disagree that the Ki-45 was not a world beater even in 1942, but compared to what else options the Japanese Army actually had open to them, and certainly what they had in service, it was probably in some respects (fx fire power) the best they had in 1942 and for some time after that. I do believe the Ki-96 should have been purshued more vigorously.

 

[tomo pauk]

First i agree that Ki-44 was pretty good mid war, with the caveat that it could use heavier armament earlier. i'm not certain that the IJAAF can make do with it as their only front line fighter until the Ki-84 shows up.

IJA cannot do with Ki-44 as their only front-line fighter, because of the low production numbers. 1200+ pcs is too small a number, for example the Ki-43 was produced in almost 6000 pcs during it's longer production run that eventually involved production lines in two factories.
Having Japan making 3000-3400 of Ki-44s at Kawasaki instead of 1700 Ki-45s would've represented a significant boost to the IJA fighter force and overall capability.

Kawasaki making a good fighter earlier than historically may prove problematic. The Ki-60 seem not to have suffered only from manouverability issues on account of its high wing loading. For the first protoype: "The aircraft displayed some lateral instability, excessively heavy control and poor control response, it demanded an unacceptable long take off run in normal loaded condition; its spinning characteristics were considered 'dangerous'; its stalling speed was extremely high" Green, William and Swanborough,Gordon: Japanese army fighters: part 1 Macdonald and Janes 1976: p20. Speed for the prototype was only 548 km/h, raised to 560 in the subsequent prototypes with 5000 meters being reached in six minutes. No significant improvement in handling was present, Ibid.

It's questionable if a radial would in itself have cured that problem, and unless it gave more power performance would suffer. Eventually the Ki-61 emerged as the 'fixed' Ki-60 so I see little chance of achieving anything wortwhile until the historicallyKi-100 becomes a possibility, granted that could probably have happened well before 45.

My suggestion - have the Ki-60 and then the Ki-61 to be designed from day 1 with a radial engine in the nose. Whatever of those two is a better fighter gets produced in series by 1942.

I do not disagree that the Ki-45 was not a world beater even in 1942, but compared to what else options the Japanese Army actually had open to them, and certainly what they had in service, it was probably in some respects (fx fire power) the best they had in 1942 and for some time after that. I do believe the Ki-96 should have been purshued more vigorously.

Ki-44 was tested with two 40mm 'grenade launchers' in the wing. Instead of that, install two 20mm cannons. Similar for the Kawasaki's fighter.
A 4 HMG armed 1-engined fighter is also very useful for tackling anything that is not a B-17, F4U or F6F, by what time the IJA can have each fighter armed with 2x20mm guns + MGs.

IJA can certainly look at the hated neighbor's yard (ie. IJNs) and see that A6M carries two cannons while just needing half the engines the Ki-45 used. Then work from that position.

 

[Just Schmidt]

IJA cannot do with Ki-44 as their only front-line fighter, because of the low production numbers. 1200+ pcs is too small a number, for example the Ki-43 was produced in almost 6000 pcs during it's longer production run that eventually involved production lines in two factories.
Having Japan making 3000-3400 of Ki-44s at Kawasaki instead of 1700 Ki-45s would've represented a significant boost to the IJA fighter force and overall capability.



My suggestion - have the Ki-60 and then the Ki-61 to be designed from day 1 with a radial engine in the nose. Whatever of those two is a better fighter gets produced in series by 1942.



Ki-44 was tested with two 40mm 'grenade launchers' in the wing. Instead of that, install two 20mm cannons. Similar for the Kawasaki's fighter.
A 4 HMG armed 1-engined fighter is also very useful for tackling anything that is not a B-17, F4U or F6F, by what time the IJA can have each fighter armed with 2x20mm guns + MGs.

IJA can certainly look at the hated neighbor's yard (ie. IJNs) and see that A6M carries two cannons while just needing half the engines the Ki-45 used. Then work from that position.

I suppose I just assumed we agree (in another thread) that theKi-44 should receive much higher priority than historically, even if I am not entirely convinced theKi-43 dosn't have its uses throughout 43. certainly it was produced in too many numbers for too long. What I'm getting at with the Ki-60 (and 61) is that I doubt they will result in anything that can best the Ki-44 in a reasonable time frame (and the 60 probably not ever), supposing that they use the same engines. I think I already suggested the German 20mm's that went into the Ki-61's be assigned the Ki-44.

As for the relative usefulness/uselessness of the Ki-45 I doubt we'll ever agree. Maybe I'm simply too fond of it.

 

[tomo pauk]

I suppose I just assumed we agree (in another thread) that theKi-44 should receive much higher priority than historically, even if I am not entirely convinced theKi-43 dosn't have its uses throughout 43. certainly it was produced in too many numbers for too long. What I'm getting at with the Ki-60 (and 61) is that I doubt they will result in anything that can best the Ki-44 in a reasonable time frame (and the 60 probably not ever), supposing that they use the same engines.

I don't hope for Kawasaki's product to be necessarily better than Ki-44, but that Kawasaki can add to the numbers. IOW - quality is there, but quantity is lacking, and that problem need to be addressed.

I think I already suggested the German 20mm's that went into the Ki-61's be assigned the Ki-44.

Be it German or Japanese or both, just get the darned 20mm cannons on fighters by many hundreds and then by thousands.

As for the relative usefulness/uselessness of the Ki-45 I doubt we'll ever agree. Maybe I'm simply too fond of it.

No worries, mate

 

[Shortround6]

Be it German or Japanese or both, just get the darned 20mm cannons on fighters by many hundreds and then by thousands.

Heck, just get four 12.7mm guns per plane and would it be a quantum jump forward.

To get better single engine fighters you need higher powered engines, not using the same engines as the Ki-45 or the engines used in the Ki-43.

You need either the V-12 engines or 1250hp radials in 1941/42 or 1400-1500hp engines in late 1942 or in 1943.

 

[tomo pauk]

To get better single engine fighters you need higher powered engines, not using the same engines as the Ki-45 or the engines used in the Ki-43.

You need either the V-12 engines or 1250hp radials in 1941/42 or 1400-1500hp engines in late 1942 or in 1943.

Me, I'd suggest that Japan forgets the V12 alley. The 1250 HP radials were in series production at Nakajima by 1941, Mitsubishi was making 1500 HP radials already in 1941.
Have Kawasaki making either Nakajima's or Mitsubishi's powerful engines for Army needs; they were making Nakajima's engines anyway before and during the Ha-40 production.