I think that Ki44 is a good fighter.
However, Ki44 is not used widely.
Many of Ki44 described by the battle report of USAF were misconception.
They have a high possibility that it was Ki84.
We think that the reason of high evaluation of Ki44 in USA is taken for Ki84.
J of J2M is translated as Land base Interceptor.
But it is not so right.
For example, ZeroMk1 (A6M2 a&b, Model 11&21) were "J" and "A."
And ZeroMk1Mod2 (A6M2b) was "A" (Kanjyou Sentouki).
ZeroMk1Mod1 (A6M2a) was "J" (Kyokuti Sentouki).
Although "A" was translated as the aircraft carrier fighter, in fact, it was the fleet defender.
And "J" was the Naval base defender.
The plan name of A6M was a high-speed fleet defender@with@20mm@cannons.
According to the classification of the fighter of IJNAF, "A" and "J" do not almost have a difference.
"A" can apply by aircraft carrier.
The main duty of J2 was Bomber Interceptor.
And the main duty of A6 was also Bomber Interceptor.
So, IJNAF was due to change all Land base Fighter into J2M.
Therefore, the production plan of A6 in the Mitsubishi aviation was reduced.
(The Mitsubishi aviation tended to convert J2 into the aircraft carrier fighter as of 1941.)
But J2 had the problem on which a propeller and engine sympathetic vibration.
For the reason, the number of production has not been increased.
It is the reason which continued producing ZeroMk1 (A6M2b) by the Nakajima aviation till 1944.
The Mitsubishi aviation wanted to reduce production of ZeroMk2.
The Nakajima aviation wanted to exchange production for ZeroMk2.
IJNAF wanted to supply ZeroMk2 of the Mitsubishi aviation to the land base first.
IJNAF wanted to exchange a land base fighter for J2M of the Mitsubishi aviation after that.
And IJNAF wanted to supply ZeroMk2 of the Nakajima aviation to aircraft carriers.
But the Mitsubishi aviation has not mass-produced J2M.
All ZeroMk2 of the Mitsubishi aviation was supplied to Solomon of grueling battlefield.
Still more, since the fighter was lacking, ZeroMk1 of the Nakajima aviation was supplied to Solomon.
Fighters will become short supply supposing the Nakajima aviation converts production into ZeroMk2.
Therefore, the Nakajima aviation continued producing ZeroMk1.
Incidentally Major Aramaki, japanese army most famous test pilot, compared Ki44 with J2 as follows.
J2 is excellent in controllability, dogfight, and the maximum speed.
And J2 is easy to land.
The climb performance of Ki44 is better than J2.
How do you consider that the test pilot of IJAAF said that J2 was better?
Digression.
Are A6M a high-speed fighter?
Of course, IJNAF considered that A6M did not become a high-speed fighter.
Therefore, IJNAF asked Germany the performance designed by this specification.
By airplane of this specification, Germany(Heinkel Avi?) said that 310 miles/h were possible.
For the reason, IJNAF judged the plan of the Mitsubishi aviation to be appropriate.
IJNAF wanted to increase the maximum speed as much as possible.
For the reason, it became such a plan name.
Thank you for reading my poor English.
