Ki-44 true designation

[greybeard]

It is well known that the most widespread version of Shoki was the type II, armed with four 12.7 mm MG's. The point is which is true subtype and its name.

So far most sources mentioned it as "b", that is Ki-44IIb. Now I found on Wikipedia also Ki-44IIc. But giving a glance to Japanese version for the "Tojo", I watch what follows:

Well, giving for granted that Japanese do know what they're speaking of, I see the type II with four 12.7 guns is the IIc (like mentioned by English Wiki), but the ideogram right after "II" reads "Hei" (a big thanks to Google translator, that filled a gap of millennia) which also means "third". May be not a coincidence that the Ki-44Ib carries same armament...

Other odd things are engines horsepowers, different from that of western sources (1250 instead of 1200 for the type I and 1450 instead of 1520 for the type II powerplant). Also, ideograms for first and second types aren't as one may guess "first" and "second" (should be "Ko" and "Otsu" respectively) but "armor" and "B" (at least this is what Google renders).

Eventually, I wonder if someone could help me to satisfy this odd curiosity of mine; thanks in advance for any help and sorry for the disturb.

 

[greybeard]

Perhaps I found an answer to my own question. Quoted from Nicholas Millman, author of "Ki-44 'Tojo' Aces of World War 2":

"Otsu was manufactured from s/n 1356 beginning in August 1943 (after ko). A lot of references imply that otsu had 40mm wing armament
as standard. It could be fitted as 'special equipment' to this version but the standard otsu configuration was cowling 12.7 weapons
only and no wing armament (same as Hayabusa).

Hei was manufactured from s/n 1750 beginning in April 1944 (this was the version with 4 x 12.7).

I don't know why early references confused the sequence but can only speculate a belief at that time that the 40mm was introduced as a
late-war anti-B-29 weapon rather than during the late summer of 1943. What is apparent from intelligence reports is that some otsu
(as manufactured) were retro-fitted with 12.7 wing armament, becoming effectively hei. There were a series of armament trials held
between otsu and hei manufacture that effectively decided the subsequent hei configuration."

I can only add that confusion could be also favoured by similarity of "Hei" armament with that of "Ib" (or "I Otsu").

Can't still find evidence of the most produced version, but due also to retro-fitting on IIb of IIc armament, it looks confirmed that it was the "II Hei".

 

[Shinpachi]

Hello, greybeard.

You had better read ko as a, otsu as b and hei as c.
If I may correct your diagram based on FAOTW(Famous Airplane of the World!), a right answer will be like follows.

* Model 1a (Ki44-1a): Engine Ha41(1250hp) with 12.7mm cannon x2(wing) 7.7mm machine gun x2(nose)
* Model 1b (Ki44-1b): 12.7mm x4 (2 for nose, 2 for wing)
* Model 2a (Ki44-2a): Engine Ha109(1450hp) with 12.7mm x2(wing) 7.7mm x2(nose)
* Model 2b (Ki44-2b): 12.7mm x2(nose) No guns but 40mm rocket(Ho301) x2 mountable in the wing.
* Model 2c (Ki44-2c): 12.7mm x4 (2 for nose, 2 for wing). OPL gunsight.
* Model 3a (Ki44-3a): Engine Ha145(2000hp) 20mm cannon x4 (2 for nose, 2 for wing) Plan Only.
* Model 3b (Ki44-3b): 20mm x2(nose) 37mm (Ho203) x2(wing) Plan Only.

 

[greybeard]

Arigato, Shinpachi!

Best regards,
GB

 

[windswords]

And Tei as "d". I belioeve the Ki-44-III (prototype only) had a turbo charger for high altitude performance but I may be wrong.

 

[Shinpachi]

You are welcome, greybeard!

Yes, it's d for Tei, windswords!