Am I the only person in the world who's a fan of the Ki-43

[Shortround6]

A problem with trying to use total scores like the Ki 43 shot down more aircraft than any other Japanese Army fighter is that they built more Ki 43s than any other Japanese Army fighter.
Around 6000 compared to 1225 Ki 44s, 3500 KI 84s and 3100 Ki 61s.
The Ki 43 got an early lead in the scoring race being pretty much the only game in town for the initial attacks and for 1942. Even in 1943 it took the first 6 months to even build 200 KI 61s let alone deploy them to combat zones. The Ki 44 was little better with 138 built in 1942 and about 220 in the first 6 months of 1943.
The Ki 43 had 616 built in 1942 and another 558 built in the first 6 months of 1943.
The Ki 43 may have better serviceability and better sortie rates than the Ki 61 and Ki-84s.

By mid 1943 the Ki 43 was a has been. Keeping itself from being shot down is NOT good enough. It has to shoot down Allied fighters and bombers not on occasion but in sufficient numbers to stop the allies and this it could not do.

 

[Glider]

I have always believed that the Ki84 was more than good enough to give any allied fighter a hard time. It was fast, agile, well armed and an excellent climb.
Far from perfect but if I had to go with a IJA fighter against a P51, that would be my choice.

The Ki43 was elegent agile with first class handling but past it as a fighter

 

[Shortround6]

It is not just fighter duels. The Japanese needed a fighter/interceptor in 1943 (at least) that could deal, not with the B-29, but with A-20s, B-25s and B-24s that were bombing the island and mainland bases and destroying hundreds of planes on the ground. Sure the Ki 43 shot down some of them but two 12.7mm machine guns with 250rpg each doesn't really allow for multiple intercepts or less than expert gunnery.
The Japanese Army needed a standard fighter that had adequate firepower to deal with the B-25s and B-24s. Not hundreds of lightly armed fighters and dozens of slightly better armed interceptors.

 

[GregP]

Hi Shortround,

I follow your logic above in post #81, but I don't see the problem. Regardless of how many of what were buiilt, the Ki-43 shot down whatever it shot down. This is not disagreement or a challenge of any sort. It's more of a question.

My curiosity comes from never having seen any data on Japanese aerial fighting that tracks these sorts of data. If anyone HAS data on the Japanese Army and Navy air operations during the war, it would be great to see it. Perhaps we could find out how many were shot down by what types as well as the number of combat sorties each. From that we could get, say, victories per combat sortie. That SHOULD even things out a bit, except for the apparent overall drop in Japanese pilot quality as the war wore on and training got more and more abbreviated before combat assignments.

What do you think? Are these data available anywhere for us to look through, as far as you know? If so, could you share a good source?

Thanks!

 

[Greg Boeser]

The 308th BG learned the hard way that B-24s required escort to get past Ki-43s over China in 1943.

 

[taly01]

Although not a great destructive power with Ki-43 2x12.7mm it is possible to damage a plane so much it was a written off as a wreck. There are many accounts I read of allied bombers making it back in shot up planes planes and injured or dead crewmen.

The Ki-61 started with German U-Boat imported 20mm MG/151 cannon in 10/1943, so there was no JAAF cannon for available for Ki-43 anyhow!

 

[GrauGeist]

Although not a great destructive power with Ki-43 2x12.7mm it is possible to damage a plane so much it was a written off as a wreck. There are many accounts I read of allied bombers making it back in shot up planes planes and injured or dead crewmen.

The Ki-61 started with German U-Boat imported 20mm MG/151 cannon in 10/1943, so there was no JAAF cannon for available for Ki-43 anyhow!

The type 99 20mm cannon was available, and in in use by the IJN, from 1939 onward and used on such types as the A6M.

The Ho-3 20mm was in use before 1941, on such Army types as the KI-45.

So the potential was there for the KI-43 to have better armament from the start.

 

[Shortround6]

Photo of the HO-3 cannon

Sources disagree on rate of fire with rates of 300rpm to 420rpm showing up. It used cartridge very close to the HIspano in power but a bit larger in dimensions. The gun itself was a bit lighter than the Hispano.
With the drum feed this is going to be very difficult to put in a wing. The only plane to use the fixed gun in service was the Ki 45 twin engine fighter and it may have used the radio operator/rear gunner to change magazines. Most sources say the drum was of 50 rounds capacity with the turret gun using 15 round magazines.

There is no doubt that B-24 were not invulnerable or that Ki 43s did not shoot them down. However it took good tactics and flying.

From an Ospry book so.....

"Through trial and error the Ki-43 sentais in Burma developed effective tactics for attacking the B-24- targeting the aircraft from the front quarter, aiming at the cockpit or engines and making concentrated, repeated attacks on a single bomber, preferably the lead Liberator in a formation"

A fighter with double the firepower might well have to use similar tactics but might require fewer firing passes per attacking plane allowing for an attack on a second/third plane before running out of ammo.
In 22 missions in 1943 (perhaps not all missions flown but just missions that resulted in air combat?) the 7th and 308th had 15 missions that resulted in either 1 or 0 losses (damaged planes not counted) while 7 missions accounted for 22 out of the 31 planes lost.

 

[tomo pauk]

I'll point the folks to the latest set of jewels posted by our very own Paul in this thread:

TAIC 1 Report Japanese Aircraft

It seems the Ho-3, with RoF of 300 rpm, was an adaptation of anti-tank 20 mm weapon. Recalling that French managed to install the big Hispano in the small wings of the Bloch fighters, the Ho-3 should've fit in the bigger wings of the Ki-43. With a combined RoF of 600 rpm, such armed Ki-43 would've stood decent chances to kill a B-24, let alone the B-25/A-20/Beaufighter.

 

[Shortround6]

Note bulge in underside of wing. The Hispano guns were turned on their sides like was done in Spitfires and unless the French knew something the British didn't (and didn't tell the British) one could expect the same problems.
I have no idea what happens when you turn the Japanese gun on it's side as far as reliability goes. With the double drum magazine (two 25 round spools?) even flipping the gun 90 degrees may mean bulges top and bottom plus the drag of the gun barrels. I am not sure how much more of hit the KI-43 could take to performance.
This assumes you can redesign the wing to have a suitable gun bay (and it never even got a 7.7mm gun historically) without taking away from other projects. There were the Ki-62 a Nakajima competitor to the Ki 61 with the same liquid cooled engine and the Ki63 was was a radial powered version of the Ki-62, both never made to actually cutting metal but some work was Incorporated into the Ki 84.

Using hindsight the Japanese best option would have been a big wing Ki-44 or Ki-84 "junior" using the same engine as the Ki-44.
Ramp up production of the 12.7mm gun and use four per airplane (minimum) and switch to the 20mm Ho-5 when available.

 

[tomo pauk]

I'll have to scratch the idea of installing the Ho-3 without the wing going through a major redesign - looks like the wing was with at least 3 spars - cutaway

Using hindsight the Japanese best option would have been a big wing Ki-44 or Ki-84 "junior" using the same engine as the Ki-44.

Maybe the Ki-61 airframe + Ha-109, but of course do it from get-go? Gets the equivalent of Ki-100 in 1943 instead of 1945. Ha-112 installed on the Ki-100 was with 1250 CV at 5800m; Ha-109 was with 1320 CV at 5250m. Ha-41 was with 1260 CV at 3700m.

 

[taly01]

Ki-43-II only had a 373mph dive limit, so adding wing guns may have risked of wing failure! Putting the little Type 99-I 20mm (MG FF) in the cowling might have been the best option as they weigh almost the same as Type 1 12.7mm. Using data from http://planesandpilotsofww2.totalh.net/Gustin/fgun.html?i=1 (although he doesn't use cowl synchronised rpm).

2 x Type 99-I 20mm (23kg) assuming synchronised rpm fell 520 -> 370 gives 16 seconds firing time with 100rd drum.
142g bullet for 0.88kg/s each gives 1.8kg/s total (12 rounds in air/sec) for pair.

2 x Type 1 12.7mm (22kg) synchronised fire was known to be very poor (ref. Mikesh) 900 -> 400 gives 38 sec firing time with 250rd.
38g bullet for 0.25kg/s each gives 0.51kg/s total (13 rounds in air/sec) for pair.

2 x Type 89 7.7mm (7kg) synchronised fire fell from 900 -> 657rpm giving 46 sec firing time with 500rd.
11.5g bullet for 0.13kg/s each gives 0.25kg/s total (22 rounds in air/sec) for pair.

For comparison Wildcat 6x0.50cal in wings at 750rpm gives 19 seconds firing time at 240rpg.
48.5g bullet gives 0.61kg/s each and 3.6kg/s total (75 rounds in air/sec) for the 6.

Most Ki-43-I used 1x7.7 and 1x12.7 giving 0.38kg/s (18 rounds in air/sec), roughly equivalent to 1/2 a 0.50cal in the wing!

 

[Shortround6]

The type 99 could not be synchronized.
Time between initiating the firing sequence (gun fired open bolt, tripping the sear released the bolt to go forward, strip round from magazine, chamber it with sort of a crush fit and hit the primer with the bolt still moving forward) and projectile exiting the barrel was too variable.
Other guns may have fired open bolt but locked the bolt to the barrel in some fashion that gave a more consistent timing. Please remember that a propeller could make several revolutions between shots (a prop turning 1350rpm is doing 22.5 revolutions per second.)

 

[taly01]

The type 99 could not be synchronized......)

ahh yes its like a big sub-machine gun?

I ran some more numbers to find a way to improve Ki-43 guns and the best option is moving the Ho-103 12.7mm from the cowl to wing pods, no increase in overall weight and gets the full ROF, which is just more than double the poor synchronised ROF browning 50 types seem to suffer from. Also the wing fuel tanks could be reduced in size to make room for MG ammo and keep wing stresses the same, and a new fuel tank added in space behind cowl left by removed MG/ammo's to restore lost wing fuel.

The Ho-5 20mm in cowling like Ki-61-Kai is the next best option but it is MUCH heavier all up, and puts out less rounds/sec than the 12.7mm in wings would as again its based on Browning MG design!

 

[tyrodtom]

You'd have a hard time getting the JAAF to agree to remove the cowl guns, only one single engine Japanese fighter in their entire WW2 enventory relied on wing guns, some of the later Kawanishi Shidens left off the 2 cowl mounted .30s and went with 4 wing mounted 20mm cannons. But, that's the JNAF, to my knowledge there was not a single JAAF single engine fighter that relied on wing guns only.

About every WW2 combatant believed in having some central mounted armament, except America, and Britain.

Eliminating the fuselage mounted guns and their ammo cans, might free up some weight in front of the cockpit, but not much room. Guns and ammo weighs a lot more per volume than gas.

 

[parsifal]

Quality is far less important to the air superiority question to numbers. In short this explains why types like the Ki-43 had to be kept in production long after their use by dates had been exceeded.


All of the prospective replacements for the Ki-43 generated difficulties in some form or other that limited their usefulness in air combat. The Ki-61 had difficulties in engine availability, the Ki84 suffered nearly fatal issues with engine reliability and build quality, the Ki-44 was not really an effect a/c until the Ki-44 IIc variants and later (basically the latter part of 1944) and really was built for a purpose different to the raison detre behind the Ki-43.


It was probably possible for the IJA to get one or more of these successor designs up and running somewhat earlier than they did, but this could only have been done at the cost of a drop in production for some period. New types always affect outputs and operational readiness rates, and there is no guarantee as to how long it might take to get a new type into production and flying effectively, or even if such an outcome were possible. In the context of the absolute desperation the IJA found itself in from quite an early point in the war, it made sense to keep churning out and making small changes to the proven warhorse of the Ki-43. At least by keeping these types going, the IJA could mount a challenge to allied incursions and each time that was made necessary, it meant further delay and more effort and more losses for the allies. This gave japan time with which to search for answers to her dilemma. The fact that such answers were never found is hardly the fault of the Ki-43.

 

[The Basket]

I could say I love the Sopwith Camel and how wonderful it is but by 1945 it's utterly useless.
It ain't a reflection on the machine or the people who flew it or designed it or built it.
But useless it is.
And that in a nutshell describes the Hayabusa in 1945.

If the RAF were still dependent on the Hawker Hurricane as a front line in 1945 then that ain't good. You could argue that's ok and the Hurricane is a fine fighter but not in 1945 it ain't.

 

[GregP]

The same can be said for even the Vickers Vixen that wasn't adopted and also isn't relevant.

How did the Hurricane and Camel get into this?

It's about the Ki-43!

Most air victories were the result of an unwary pilot falling prey to ambush, or a 1st-pass kill. The Ki-43 in 1945 had about the same chance as it always did after the Hellcat arrived. If it surprises you in-flight, it might not be a good day for you. The thing to do is pay attention to the business of combat flying. A great pilot in a Ki-43 in 1945 probably would beat an average one in a better airplane, same as it has always been.

Was it outdated? Yes. But it was still armed and dengerous if flown well. So was the late-model Zero.

 

[Shortround6]

Yep, IF you can surprise the other aircraft and IF you had a skilled pilot in the Ki 43 it could be dangerous.
BUT that wasn't the situation all to often for the Ki-43 from 1943 on. It was often tasked with bomber interception. (B-24s and B-25s, in 1943 and early 44) and surprising even a small bomber formation with tail gunners and top turrets was a lot harder. Japanese found (like the Germans) that head on passes were the least dangerous to the attackers due to lack of power turrets in the front. Unlike the Germans with either Fw 190s or 109s with under wing cannon it took even good pilots multiple attack runs to down a single bomber, due to lack of fire power. Once the bombers got escorts things got even worse for the Ki 43s. Yes the Ki 43s shot down bombers but a better plane would have done a lot more.
The main problem with the Ki-43 was that they built around 2750 of them in 1944. That is equal to ALL the Ki 61s built in 1944, ALL the Ki 44s built in 1944 and about the production of the K-84 for the first 1/2 of 1944 all put together. Ki-84 production increase substantially in the last 1/2 of 1944.

To put that much production effort into a plane that carried TWO 12.7mm guns with 250rpg when you needed bomber interceptors sure seems like a mistake to me.

 

[Jenisch]

I wonder if the low top speeed of the Ki-43 was necessarily a consequence of the Japanese desire for maneuverability, or if it was fault of a lack of more powerful engines in Japan. People assume the Oscar and the Zero were slower than Allied fighters of their class (like the P-40) because the Japanese wanted planes basically for dogfight. I'm skeptical about this, because in order to enter in a dogfight, you have to reach your enemy first. If you can't or if this is difficult, it just doesn't make sense. Just look at the Yak-3 for instance. Very light, very agile, but adequate in terms of performance. And as I have said earlier, the Zero did not had this performance issue against the Wildcat. It did lacked pilot and fuel tank protection, and dive speed, but not level flight speed. So it's pilot's could chase Wildcats in level flight without having to worry about performance. Now a Ki-43 against a P-40E, I guess the IJA pilot's must have felt lack of performance. Specially in the first production model of the Hayabusa.