AerialTorpedoDude69
Airman 1st Class
- 159
- Mar 1, 2022
Lots of great comments here, sorry to only address a few.
IIRC, Allied bombers didn't begin hitting Mitsubishi factories and sub manufacturers until December of 1944. So the reason for Mitsubishi's inability to make more Raidens was (just as you say) multifold. Chief among these factors was the supply shortage caused by Allied raids on Japanese shipping. And the supply shortage is what led to greater emphasis on a cheaper fighter. Something that Japanese war planners had foreseen during the development of the Zero. An island nation that was dependent on imports would have to build cheaper, lighter aircraft if there were ever a disruption of the supply chain.
However, another major reason was that the Raiden and Ki-44 were designed for different purposes. The Ki-44 was designed with the ground war in China in mind. In fact, almost all Ki-44s were sent to Indo-China. The Navy, on the other hand, was still primarily engaged in combat that involved extremely long ranges and therefore a fighter like the Raiden wasn't in demand until Allied bombers were flying with impunity over Japan in the Summer of 1944. There were likely Ki-44s stationed in Northern Japan as well in order to protect against the Kuril and Hokkaido raids, but I know very little about this part of the war.
But more or less, I think you and Tomo are right that price alone wasn't a determining factor, but rather just one factor among many.
Unfortunately, I don't know how much the Kasei 23a production cost versus the Homare 21, but they weighed about the same and the 23a's fuel injection system was undoubtedly more complicated and expensive than a carb system (although the bowl-prime on the Homare 21 was regarded as having elements of a direct injection system). Maybe the Homare required more man-hours to produce, but it couldn't have been much more. Otherwise, the Ki-84's total manufacturing costs were supposedly almost half that of a Ki-44 or Ki-43 (IIRC, this is according to Richard Bueschel's book), which themselves were fairly cheap aircraft from a materials standpoint but required massive amounts of manpower to produce, as with all Japanese aircraft.
Keep in mind that a P-51 was like 2,000 man hours and a Spitfire was around 13,000 man hours. While there are no man-hour or cost numbers for a Raiden, we can guess that it was more complicated to build than a Zero based on its weight, extension shaft, and laminar wing. Also, to bolster your point, the Ki-61 had to have been one of the most expensive Japanese aircraft of the war given its weight, its high aspect wing, the absurdedly robust diving speed, and other advanced features and yet the Japanese built around 3,000 of them. Perhaps the Army's military planners were more likely to adopt expensive aircraft given that they didn't have to launch aircraft from carriers?
I can see that my thinking is overly reductionist in this regard. You are right that there is more complexity to Japan's aircraft design paradigm than just cost. Though, I do have some questions about the Ki-61. Like, why? The Ki-44 was available earlier and offered similar performance. It just didn't make sense to make the Ki-61. And on top of that, the Japanese had already added MW50 to a DB601A. The Ki-61 just seemed like too much effort for very little advantage over the Ki-44. And on top of that, the Ki-61 could have been a much better plane with just a little more effort and expense. But that is a conversation for a separate thread.
I have to point out that Ki-44 production also terminated at the end of 1944 and had been slowed since early 1944. On the other hand, Raiden production, which had never been more than a trickle, reached their peak in June of 1944. But even at the peak of Raiden production, almost twice as many Ki-44s were being made. So even with huge demand for Raidens, and Ki-44s being phased out, more Ki-44s were being manufacturered.
IIRC, Allied bombers didn't begin hitting Mitsubishi factories and sub manufacturers until December of 1944. So the reason for Mitsubishi's inability to make more Raidens was (just as you say) multifold. Chief among these factors was the supply shortage caused by Allied raids on Japanese shipping. And the supply shortage is what led to greater emphasis on a cheaper fighter. Something that Japanese war planners had foreseen during the development of the Zero. An island nation that was dependent on imports would have to build cheaper, lighter aircraft if there were ever a disruption of the supply chain.
However, another major reason was that the Raiden and Ki-44 were designed for different purposes. The Ki-44 was designed with the ground war in China in mind. In fact, almost all Ki-44s were sent to Indo-China. The Navy, on the other hand, was still primarily engaged in combat that involved extremely long ranges and therefore a fighter like the Raiden wasn't in demand until Allied bombers were flying with impunity over Japan in the Summer of 1944. There were likely Ki-44s stationed in Northern Japan as well in order to protect against the Kuril and Hokkaido raids, but I know very little about this part of the war.
But more or less, I think you and Tomo are right that price alone wasn't a determining factor, but rather just one factor among many.
See above for the production numbers relative to Japanese production capabilities.
Unfortunately, I don't know how much the Kasei 23a production cost versus the Homare 21, but they weighed about the same and the 23a's fuel injection system was undoubtedly more complicated and expensive than a carb system (although the bowl-prime on the Homare 21 was regarded as having elements of a direct injection system). Maybe the Homare required more man-hours to produce, but it couldn't have been much more. Otherwise, the Ki-84's total manufacturing costs were supposedly almost half that of a Ki-44 or Ki-43 (IIRC, this is according to Richard Bueschel's book), which themselves were fairly cheap aircraft from a materials standpoint but required massive amounts of manpower to produce, as with all Japanese aircraft.
Keep in mind that a P-51 was like 2,000 man hours and a Spitfire was around 13,000 man hours. While there are no man-hour or cost numbers for a Raiden, we can guess that it was more complicated to build than a Zero based on its weight, extension shaft, and laminar wing. Also, to bolster your point, the Ki-61 had to have been one of the most expensive Japanese aircraft of the war given its weight, its high aspect wing, the absurdedly robust diving speed, and other advanced features and yet the Japanese built around 3,000 of them. Perhaps the Army's military planners were more likely to adopt expensive aircraft given that they didn't have to launch aircraft from carriers?
I can see that my thinking is overly reductionist in this regard. You are right that there is more complexity to Japan's aircraft design paradigm than just cost. Though, I do have some questions about the Ki-61. Like, why? The Ki-44 was available earlier and offered similar performance. It just didn't make sense to make the Ki-61. And on top of that, the Japanese had already added MW50 to a DB601A. The Ki-61 just seemed like too much effort for very little advantage over the Ki-44. And on top of that, the Ki-61 could have been a much better plane with just a little more effort and expense. But that is a conversation for a separate thread.