Wild_Bill_Kelso
Senior Master Sergeant
- 3,231
- Mar 18, 2022
Very interesting, I never realized that, always thought it was short and fat... I hadn't considered the position of the engine etc.
Jack vs. Tojo - Which was better? Why?
- Thread starter Conslaw
- Start date
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Very interesting, I never realized that, always thought it was short and fat... I hadn't considered the position of the engine etc.
Hmmm....eyeballing that Raiden and Hellcat side by side, it appears the Raiden's engine moment would be less than normal for its size and weight class, making aft structural weight critical for CG reasons. Betcha it was real snappy in the vertical fight. Not much polar moment. I was re-reading The Right Stuff (strolling down memory lane) for giggles last night and was struck by how the silhouette of the Raiden in that pic called to mind the Bell X1.
Wild_Bill_Kelso
Senior Master Sergeant
- 3,231
- Mar 18, 2022
I was looking at this photo, and noticed that if you shorten the Raiden's nose, it looks a lot like a (slightly hump-backed) F6!
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GregP
Major
The radial is in front of the wing leading edge and the driveshaft is something like 3 feet long or so. the cockpit is enormous when compared with other fighters of similar size. it is a big cockpit even next to a P-47!
AerialTorpedoDude69
Airman 1st Class
- 150
- Mar 1, 2022
Just a quick note here:
The Ki-44 II didn't receive the continuous development that the other airframes received, probably because the airframe itself wasn't that great.
For example, thrust stacks were never added, except as a field modification (and they contributed around 8-10 MPH, making it almost as fast as a Frank. More crucially, it never got water methanol injection. And its airfoil, which was an NN-2 (similar to the Ki-43), was fairly draggy. Overall, the airframe had been maxed out so the designers didn't invest any more development effort into it. And as an interceptor, its high altitude performance sucked, particularly in comparison to aircraft that had direct injection engines, such as the Ki-61 II and the J2M.
The Jack, in comparison, had a lot more stream-lining, a laminar-flow wing, a direct injection engine that performed better than most of the carbureted engines (all of the Japanese engines lacked a sufficient supercharger) at high altitude.
The main issue here is that the Japanese high command didn't invest enough resources in developing a highly reliable interceptor. They instead focused on high output engines that weren't reliable. The main thing to take away is that they missed an opportunity to develop an ultra lightweight interceptor around a 1,500 HP engine with a "laminar flow" wing, thrust stacks, direct injection, alu 7075, and water methanol injection. Had they done so, they might have had a 400+ MPH aircraft that ran reliably on poor quality fuel and was capable of intercepting the B-29 at high altitude.
The Ki-44 II didn't receive the continuous development that the other airframes received, probably because the airframe itself wasn't that great.
For example, thrust stacks were never added, except as a field modification (and they contributed around 8-10 MPH, making it almost as fast as a Frank. More crucially, it never got water methanol injection. And its airfoil, which was an NN-2 (similar to the Ki-43), was fairly draggy. Overall, the airframe had been maxed out so the designers didn't invest any more development effort into it. And as an interceptor, its high altitude performance sucked, particularly in comparison to aircraft that had direct injection engines, such as the Ki-61 II and the J2M.
The Jack, in comparison, had a lot more stream-lining, a laminar-flow wing, a direct injection engine that performed better than most of the carbureted engines (all of the Japanese engines lacked a sufficient supercharger) at high altitude.
The main issue here is that the Japanese high command didn't invest enough resources in developing a highly reliable interceptor. They instead focused on high output engines that weren't reliable. The main thing to take away is that they missed an opportunity to develop an ultra lightweight interceptor around a 1,500 HP engine with a "laminar flow" wing, thrust stacks, direct injection, alu 7075, and water methanol injection. Had they done so, they might have had a 400+ MPH aircraft that ran reliably on poor quality fuel and was capable of intercepting the B-29 at high altitude.
Clayton Magnet
Staff Sergeant
- 868
- Feb 16, 2013
The J2M was a formidable fighter, assuming it was running to spec. And as per this article ( which was posted years prior) was superior to a F6F-5
Wow. Never read this before. Enlightening. But it seems that most aviation writers agree that the Ki-44 didn't get much attention from the IJA. If it had, it would likely have been operational much earlier and perhaps gotten some of the upgrades you mentioned above.
AerialTorpedoDude69
Airman 1st Class
- 150
- Mar 1, 2022
There's an early-war USAAF air combat training manual which used aircraft models to demonstrate tactics against various Japanese aircraft. The manual's instrution for engaging aircraft such as the Zero and Oscar were pretty straightforward: dive, dive, dive. Dive to attack, dive to escape.
The instructions for engaging a Tojo were tortured, complicated, and difficult. At the time, the Tojo was faster and more manueverable at many altitudes than the US planes it was facing off against (except maybe a P-38E but I'm not sure), and the Tojo could dive and roll to some extent with those aircraft. The only real way to shake one was with complex tricks that exploited some of the handling issues of the Tojo, such as its "inability" to perform certain maneuvers, such as snap rolls.
Going off the tactics the US developed, you could tell that fighting a Tojo was far more difficult than fighting against a Zero or Oscar.
Greg Boeser
1st Sergeant
When the 23rd FG began encountering them in China in mid-'43, the Tojo really freaked them out. After slapping Ki-27s and Ki-43s around for a year, they found themselves at a distinct disadvantage. When some of his pilots doubted their ability to handle tgem in the air, Chennault is reported to have said, "Well, we'll just have to beat them on the ground, then."
That's what I've read... Instead of wasting time with the Ki-61's engine, the IJA would have been much better off putting the equivalent effort in making the Ki-44 even better (or putting a Kinsei in the Ki-61 from the outset)... That way it would have remained a decent interceptor until the Shinden came along to replace it. (Though still not enough to stop the American juggernaut.)
AerialTorpedoDude69
Airman 1st Class
- 150
- Mar 1, 2022
It's an interesting dilemma that the Japanese strategic planners faced: the war in the Pacific required aircraft with incredible ranges and their carrier fleet didn't have a lot of elevators that could support larger aircraft.
They had to choose between fewer fighters available for strike missions and putting their carriers into harm's way more often or larger strike forces and putting their carriers at the edge of the effective range of their opponents strike forces. As you might expect, the IJN favored offense over defense. What I don't understand is why the IJA didn't do as you've suggested. Because the Ki-43 was, in my opinion, one of the worst aircraft of the war, despite a good combat record. While the army did fly long range missions in New Guinea, that was not the case in Indo China. It's befuddling why they didn't design the Ki-43 around the Kinsei. Had they done so, they wouldn't have needed the Ki-44.
AFAIK, the only early war Army aircraft that used the Kinsei were several transport aircraft. In comparison, USAAF early war aircraft includes the P-38E and P-47C, both excellent (and extremely heavy) aircraft. Throwing Sakae-equipped aircraft at these two beasts seems a little insufficient.
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Agree. The Kinsei had much more growth potential than the Sakae. But a Ki-43 powered by a Kinsei would still have needed a stronger structure, sealing fuel tanks, and more pilot armor--- so there might have been no improvement in level speed (but perhaps diving). Imagine the two and a half years the Japanese could have owned the skies if they had that new Ki-43 plane and an early A6M8 at the outset. The Ki-61, Ki-44 and perhaps the Raiden would not be needed. The final challenge would either be a reliable Hayate or the Ki-84 powered by an A18 or A20 engine. If that happened, then a Shinden interceptor would have been superfluous.
Admiral Beez
Captain
Is the IJN the only carrier force to specify a frontline fighter incapable of flying from its carriers? Why not make the Jack carrier capable or divert its resources to a carrier fighter? Since when is it the navy's job to intercept B-29s? That nation was messed up.
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GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
The KI-60 was an answer to the Army's request in late 1939 for a well armed interceptor built around the DB601.
The KI-61 was to be a lighter, multi-purpose version of the KI-60.
At the time of the KI-61's introduction in the early 40's, it was the only Japanese fighter that had a service ceiling of 38,000 feet, well above that of the KI-43 and A6M.
The KI-61 was to be a lighter, multi-purpose version of the KI-60.
At the time of the KI-61's introduction in the early 40's, it was the only Japanese fighter that had a service ceiling of 38,000 feet, well above that of the KI-43 and A6M.
Along these lines?
Nakajima Ki-116 - Wikipedia
One of those promising developments that never progressed very far. A couple images speculating its appearance as only one prototype was constructed.
You seem to think the Japanese had anything like coordinated strategic planning. They had an Army agenda and a Navy agenda, and never the twain shall meet. (Except at the Hirohito level, and he was reluctant to dirty his immaculate imperial robes in that muddy fighting ring.)
Making a land based fighter carrier capable (especially a small elevator carrier) is a difficult proposition and rarely 100% successful.
When it comes to B29 defense, Rule .303 applies: "If you have the resources at hand to cope with a looming existential disaster, it is your responsibility to provide whatever aid is in your power."
This was a really nice looking plane and a decent concept (as us NASA people would say, "If it looks good, it probably flies good"), but too much like the Ki-100 and not fast enough... When the Homare engine was performing as specified, the Hayate was truly formidable... But this plane would have experienced difficulties with a Mustang or Corsair piloted by someone experienced in BNZ not interested in dogfighting...Along these lines?
Nakajima Ki-116 - Wikipedia
en.wikipedia.org
One of those promising developments that never progressed very far. A couple images speculating its appearance as only one prototype was constructed.
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Shortround6
Major General
I see problems with the timing of some of these engines.
The Kinsei 61/2 engine was a very good engine, trouble is when does it show up? If the Kinsei 61 doesn't show up until 1944 it doesn't do the Japanese much good.
The Kinsei 54 was good for 1300hp for take-off, 1200hp at 3,000 meters and 1100hp at 6,200 meters. This showed up in 1942 (?)
The engine in the Ki-43 II was good for 1150hp for take-off, 1150hp at 2450 meters, and 980hp at 5600 meters.
The engine in the Ki-61 was good for about 1175-1180hp for take off and 1080-1100 hp at 3500-3900 meters. This is actually with a few percent of the Allison engines used in the P-40s/P-39s except the Japanese can't use WER.
At the time they working on the Ki-61 (1940-1941) the Kinsei engine may have been the 40 series engines, these had single speed superchargers and around 1080hp at 2000 meters for many versions.
The Ki-44 II with the Ha-109 engine shows up in the very late fall of 1942. This engine has the power to get the job done in late 1942 and into 1943. (Showed up in the Ki-49 bomber before the Ki 44 fighter).
The Japanese put two speed superchargers on many of their engines (along with other improvements) in 1940-41-42, later on there seems to have been a number jump in power so be very careful when trying to figure out what the Japanese could have done in 1941-43 as, just like the allies, many of the 1944 engines did not exist in 1941-1943.
The Kinsei 61/2 engine was a very good engine, trouble is when does it show up? If the Kinsei 61 doesn't show up until 1944 it doesn't do the Japanese much good.
The Kinsei 54 was good for 1300hp for take-off, 1200hp at 3,000 meters and 1100hp at 6,200 meters. This showed up in 1942 (?)
The engine in the Ki-43 II was good for 1150hp for take-off, 1150hp at 2450 meters, and 980hp at 5600 meters.
The engine in the Ki-61 was good for about 1175-1180hp for take off and 1080-1100 hp at 3500-3900 meters. This is actually with a few percent of the Allison engines used in the P-40s/P-39s except the Japanese can't use WER.
At the time they working on the Ki-61 (1940-1941) the Kinsei engine may have been the 40 series engines, these had single speed superchargers and around 1080hp at 2000 meters for many versions.
The Ki-44 II with the Ha-109 engine shows up in the very late fall of 1942. This engine has the power to get the job done in late 1942 and into 1943. (Showed up in the Ki-49 bomber before the Ki 44 fighter).
The Japanese put two speed superchargers on many of their engines (along with other improvements) in 1940-41-42, later on there seems to have been a number jump in power so be very careful when trying to figure out what the Japanese could have done in 1941-43 as, just like the allies, many of the 1944 engines did not exist in 1941-1943.
AerialTorpedoDude69
Airman 1st Class
- 150
- Mar 1, 2022
In "Secret Weapons and World War II: Japan in the Shadow of Big Science" the author mentioned that Japan was on the verge of developing the neccessary bureaucracy for sharing military technology between different service branches, but the chief organizer died in 1940, just prior to implementing the system. He had only managed to establish a basic framework which both services did not invest many resources in.
You may have misunderstood my poorly written comment though. I was not saying they needed an inter-service aircraft, but rather critiqued the IJA's decision to use the Sakae on a land-based fighter. They should have used the Kinsei. While the Ki-116 would have been great, stapling the Kinsei on any random aircraft isn't preferable over a purpose-built aircraft.
The fuel-injected derivative of the Kinsei became available in late 1941 (According to Goodwin, though, it was available in 1940). It reached aircraft in late 1942, such as the Ki-46 III. Jiro Horikoshi mentioned in his book that a 1,500 HP Zero could have made its way into combat by the Summer of 1943, enough to slow the progression of the war. I think the big problem wasn't the engine though. The issue was that the airframe was obsolete. That big draggy wing that the Japanese used on their fighter aircraft, which improved slow-speed lift at the expense of top maximum speed and sustained turn rate, would never be able to perform at high speed. It didn't matter what kind of engine was used. The faster a Zero went, the poorer its turn performance would become.
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