Author Topic: ki 84 plane set  (Read 2664 times)

Offline CDR1

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Re: ki 84 plane set
« Reply #15 on: October 22, 2010, 10:31:44 AM »
thks for all the info, I thought it would relatively easy to adjust the weapons and weight and give the IJA set a uber buff hunter, rather than build a whole new "raiden". On use and numbers to qualify a plane in the game, I looked at me 163 and it seems they managed to shoot down 4 allied bombers and lost 19 pilots ( mostly accidents). although the coolness of having a reliable 163 in the game cannot be overestimated. Thks again.

Offline nrshida

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Re: ki 84 plane set
« Reply #16 on: October 24, 2010, 12:29:59 PM »
I have here a very old and fragile pamphlet which is either a reprint from a section of a book by Dr. Rene J. Francillon, or a separate article he wrote on the Ki-84 dated 1966.

There is a description of the evolution of the type over the approximately 18 months of production. It states 3577 aircraft produced in total which includes the pre-production prototypes, the service trial aircraft, all of the delivered production aircraft and the aircraft retained by Nakajima for testing and development.

There are essentially seven main subtypes listed with a number of intermediate or prototype variants intersposed. These include the high-altitude interceptor etc.

The final three subtypes, the Ki-106, the Ki-113 and the Ki-116 are basically emergency production variants, employing wood and steel extensively in the structure to supply for the critical shortages of aluminium alloys. The final version was a variant fitted with a lower power Mitsubishi engine. These perhaps aren't particularly interesting as the type had passed its highest stage of evolution at this point.

The first four variants described pertain to the main production types fielded and are pertinent to this discussion.

Model 1A Early Production (Ki-84-Ia)
Model 1A Late Production (Ki-84-Ia)
Model 1B (Ki-84-Ib)
Model 1C (Ki-84-Ic)

The third and fourth models listed above were collectively described by Nakajima as the Ki-84-II Hayate-Kai (the Ib and Ic being the JAAF and the Ministry of Munitions designation). The difference between the 1B and 1C was apparently only the fitting of two wing-mounted Ho-105 (Ho-155) 30-mm cannons designed for operation against the B-29. Hence the collective designation by Nakajima. There is no data pertaining to the exact numbers for the 30-mm equipped version, the article simply states 'a few' model 1C types were built with the Ho-105 (Ho-155) cannons fitted. This would be in keeping with the popular opinion that the 30-mm equipped Hayate was indeed a rarity.

However, the description of the mass production phase of the Ki-84 explains that the Model 1A was 'followed on the assembly lines' by the Model 1B in which the two synchronised machine guns were replaced with two Ho-5 20-mm cannons. This suggests that the four cannon version, the Ki-84-II Hayate-Kai, at some point of the manufacture, became the standard production model. A few of these only being converted to carry the 30-mm cannon.

The plot however thickens yet further. The article concludes with a table of specifications of the sub types. From this data it seems clear that the version we have in Aces High is the Early Production Model 1A (Ki-84-1a).

The Late Production Model 1A (Ki-84-1a) had a different version of the Homare engine with a higher power output and this version apparently also lost some weight over its predecessor. There is also some small dimensional differences unique to the Late Production Model 1A version, this seems to be due to modified wingtips and wooden rear fuselage section. This may also account for the lower weight.

As a side note the famously postwar tested Hayate was a Late Production Model 1A version. These test were ran on a higher octane fuel than was available to the Japanese armed forces during the war, but I stress that this is a separate and unique test and the results of that test should not be confused with the power outputs of the fielded aircraft. The higher power output of the Late Production model over its predecessor was due to an improved engine and not to the higher quality U.S. fuel.

The four cannon (Ho-5) equipped Ki-84-II Hayate-Kai (the Ki-84-Ib) had a different version of the Homare engine again with an even higher power output and the dimensions revert to those of the Early Production version. More interestingly, the loaded weight is given as 81 lbs LESS than the loaded weight of the Early Production Model 1A (the Aces High version).

For these three types the wing areas are identical while the loaded weights, wing loadings, power loadings and power outputs differ. So the assumption / opinion that there were simply three differently armed variants of the same aircraft is infact far from accurate.

Regarding Aces High, as far as I can tell, the exhaust manifolds for all three engines in the aircraft described above were the same. I can also see no differences to the engine cowlings, which fully enclose the muzzles of the synchronised armament on the Ki-84. Perhaps someone with access to better photographs of the four cannon model could make a contribution on this issue?

Therefore, assuming there was the will to do so, it may be an economical way to introduce a new variant, in the same way as the P-47M was introduced, with the proviso that the breeches of the cannons which are visibly in the cockpit would then be incorrect (although the whole cockpit is a little poorly detailed compared to other AH aircraft and could do with a revamp, if we're honest (sorry HTC, I mean eventually, obviously)).

Finally, the postwar tested aircraft mentioned above, the Late Production Ki-84-Ia, was still airworthy in 1963. The aircraft carried the FAA registration N3385G. I don't know if anyone knows if this aircraft is still existant?
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Offline Wmaker

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Re: ki 84 plane set
« Reply #17 on: October 24, 2010, 01:40:49 PM »
The third and fourth models listed above were collectively described by Nakajima as the Ki-84-II Hayate-Kai (the Ib and Ic being the JAAF and the Ministry of Munitions designation). The difference between the 1B and 1C was apparently only the fitting of two wing-mounted Ho-105 (Ho-155) 30-mm cannons designed for operation against the B-29. Hence the collective designation by Nakajima. There is no data pertaining to the exact numbers for the 30-mm equipped version, the article simply states 'a few' model 1C types were built with the Ho-105 (Ho-155) cannons fitted. This would be in keeping with the popular opinion that the 30-mm equipped Hayate was indeed a rarity.

Yeh, Leszek A. Wieliczko's Ki-84 book (ISBN: 83-89088-76-2) states the following about the KI-84c:

"Even more heavily armed was another version designated Yon-Shiki Sentoki Hei-Gata, i.e. Army Type 4 Fighter Model C, or Ki-84 Hei (KI-84c). This time the Ho-5 cannons were retained in the fuselage (like on the Ki-84 Otsu), whereas the wing-mounted cannons were to be replaced by new 30-mm Ho-155 II cannons (sometimes incorrectly referred to as Ho-105 or Ho-115). In fact, the Ho-155s were usually not mounted, as their development never reached a stage allowing quantity production. Reportedly, there were several cases of only one Ho-155 II mounted in the starboard wing, but there are no photographs to support this claim. (Some books contain a photograph captioned "Ki-84 Hei" but it was infact a Ki-84 Ko no. T2-302 captured and tested after the war by the Americans; the mistake results from the fact that the aircraft had long and thick fairings of the wing-mounted cannons, which implies weapons of a much greater calibre.) The Ki-84 Hei practically remained an experimental machine."


For these three types the wing areas are identical while the loaded weights, wing loadings, power loadings and power outputs differ. So the assumption / opinion that there were simply three differently armed variants of the same aircraft is infact far from accurate.

Yep this should be the case atleast in theory. Question is weather or not the -25 Homares delivered their max. output in service. Here's some discussion about this in an earlier thread: http://bbs.hitechcreations.com/smf/index.php/topic,262941.30.html


Regarding Aces High, as far as I can tell, the exhaust manifolds for all three engines in the aircraft described above were the same. I can also see no differences to the engine cowlings, which fully enclose the muzzles of the synchronised armament on the Ki-84. Perhaps someone with access to better photographs of the four cannon model could make a contribution on this issue?

b-model can be recognized from the bigger exhaust ports in the front fuselage where the firing gases expand out of.


Finally, the postwar tested aircraft mentioned above, the Late Production Ki-84-Ia, was still airworthy in 1963. The aircraft carried the FAA registration N3385G. I don't know if anyone knows if this aircraft is still existant?

AFAIK, this is the only surviving Ki-84 and is displayed in Tokko Heiwa Kinen-kan Museum at Chiran, Japan.

« Last Edit: October 24, 2010, 01:59:25 PM by Wmaker »
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Offline nrshida

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Re: ki 84 plane set
« Reply #18 on: October 25, 2010, 03:30:47 AM »
Yep this should be the case atleast in theory. Question is weather or not the -25 Homares delivered their max. output in service. Here's some discussion about this in an earlier thread: http://bbs.hitechcreations.com/smf/index.php/topic,262941.30.html

Assuming the data originated from Nakajima's own dynamometers, I think we should take the power outputs as read until it can be proven otherwise. The Nakajima Homare was a brilliant piece of engineering mass produced under increasingly difficult wartime circumstances. Aces High is intended to simulate the aircraft from this period. I think it's rather unfair to arbitrarily nobble power outputs for a particular country's aircraft.


b-model can be recognized from the bigger exhaust ports in the front fuselage where the firing gases expand out of.

Could you find any photographs Wmaker? I am still searching.


AFAIK, this is the only surviving Ki-84 and is displayed in Tokko Heiwa Kinen-kan Museum at Chiran, Japan.

That's what I thought too. When I read about the other aircraft (FAA registration N3385G) I wondered what had become of it. Apparently it was restored to flying condition by a company called Garret-AiResearch Aviation Service, which was based at Los Angeles International Airport. It was later entrusted to the staff of the California Air Museum in Ontario, California, but I can't even find that museum online. 1963 is also a long time ago now!

Phew, this researching is hard work, I'm off to fly around for a bit.
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Offline Wmaker

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Re: ki 84 plane set
« Reply #19 on: October 25, 2010, 04:14:04 PM »
Assuming the data originated from Nakajima's own dynamometers, I think we should take the power outputs as read until it can be proven otherwise. The Nakajima Homare was a brilliant piece of engineering mass produced under increasingly difficult wartime circumstances. Aces High is intended to simulate the aircraft from this period. I think it's rather unfair to arbitrarily nobble power outputs for a particular country's aircraft.

Absolutely. I wasn't talking about any arbitrary reduction of power output at all. So far I haven't heard or seen any evidence that the Ha-45-25 had reduced output. But Busa for example found in his research that the late production a-models had the output of their Ha-45-21 reduced from the projected 1990hp to the levels of the Ha-45-12 (1825hp) which was the power plant of the earlier production model-as. While it is said that the problems with the fuel pressure were rectified with the Ha-45-23, a lot of problems still remained. So I'm just saying that I find it highly plausible that the Ha-45-25 of the b-model didn't deliver its advertised 2000hp in service. Of course if no primary source is found to verify my suspision, it should have 2000hp in the sim.

EDIT/Just wanted to add that -25 was in reality very, very rare...not all model-bs had it which were rarities themselves./EDIT


Could you find any photographs Wmaker? I am still searching.

These are from Kagero publications book on the Ki-84:


Caption: Ki-84 from 104. Sentai at Nakajima factory's airfield in Ota after VJ-Day (probabaly the end of 1945). Although 104. Sentai was stationed in Manchuria, clearly some of the unit's aircraft were for some reason transferred back to Japan.


Caption: Ki-84 Otsu from 104. Sentai at the Nakajima factory's airfield in Ota after VJ-Day (camouflaged and provided with a broad, white band around fuselage). In the foreground, a partially visible fuselage of a silver colored Ki-84 Ko. Externally, the "Otsu" sub-type varies from the "Ko" in different location of the cowl gun vents.

Couple line drawings from the same book to display the difference a bit better:



That's what I thought too. When I read about the other aircraft (FAA registration N3385G) I wondered what had become of it. Apparently it was restored to flying condition by a company called Garret-AiResearch Aviation Service, which was based at Los Angeles International Airport. It was later entrusted to the staff of the California Air Museum in Ontario, California, but I can't even find that museum online. 1963 is also a long time ago now!

They are one and the same plane. Mr. Ed Lykings bought it from Planes of Fame Air Museum (museum's name changed). Then he realized how hard it would be to maintain it in air worthy condition so he sold it to Japan.
« Last Edit: October 25, 2010, 05:14:32 PM by Wmaker »
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Offline Krusty

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Re: ki 84 plane set
« Reply #20 on: October 25, 2010, 06:57:22 PM »
nrshida, I disagree with your assessment on the designations of the different models...

From what I read, The -II denoted a model built with many wooden parts to conserve metal, had the as-mentioned engine problems, but was not the same as the model we know as the -Ib. The -Ib would be identical to the -Ia but with different guns. I think you're comparing 2 different things here.

By this I mean there was both a Ki-84-Ib and a Ki-84-II and they both could have had 4x20mm cannon, but they would not be the same craft. There were differences in the construction. Wooden parts were used in a number of places to save metal. (Also, I believe wood ADDS weight, doesn't reduce it -- you need more wood for the same strength than you would for metal of the same strength. That's why aircraft were and are made of metal. It's lighter and stronger.)  As far as I know only a handful of the -II were made because the engine production was moved to underground caves and productivity was very slow (also plagued with problems, as already mentioned). You are equating them as the same plane with different names, when there were really 2 separate models.

wmaker: The distinction of the gas ports is very interesting... Now that you point it out, do you have any pictures showing if any of these -Ib's saw active service? I mean photos of them with frontline squadrons, instead of derelict on a factory parking lot well after the war is over. I would very much be interested in where and how many saw actual deployment.

Offline nrshida

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Re: ki 84 plane set
« Reply #21 on: October 26, 2010, 03:52:16 AM »
nrshida, I disagree with your assessment on the designations of the different models...

You know I find it slightly irksome Krusty, that you seem to make a habit of casually dropping by to poo poo material posted by other forum members while not actually submitting any actual material yourself to justify your claims (or rather, your objections).

Just to clarify, you aren't disagreeing with MY assessment of the designations of the different models. You're disagreeing with Dr. Rene J. Francillon's assessment of the different models. I spent several hours of studying his material before posting and I also provided a reference.

What would be really nice Krusty, would be that if a Radioactive Forum member such as yourself would actually contribute material to displace incorrect material so that our understanding of the subject broadens and deepens.

I would be more than happy to admit I was wrong about this detail or that, especially if, in proving me so, our knowledge of the subject was enhanced.

Now I have to expend energy addressing your points, in case casual readers confuse your Radioactive status with someone that is an authority on the matter.

Firstly no, the Ki-84-II Hayate-Kai might have had a wooden tail section but that is the extend of wood employed in this version. I'm still researching this at the moment.

I think you might be confusing the Ki-84-II Hayate-Kai with the Ki-106.

Would you care to share your detailed knowledge of the 'as-mentioned' engine problems you elude to?


The -Ib would be identical to the -Ia but with different guns. I think you're comparing 2 different things here.

No they are not identical at all, there were two versions of the Ki-84-Ia, as I described in my previous post. The Ki-84-II Hayate-Kai differs again. All three of the types I just listed have different engine variants, fuel capacities, loaded weights, wing loadings, power loadings, power outputs, cruise speeds, climb rates and physical dimensions.
 

By this I mean there was both a Ki-84-Ib and a Ki-84-II and they both could have had 4x20mm cannon, but they would not be the same craft. There were differences in the construction. Wooden parts were used in a number of places to save metal.

Actually they are exactly the same aircraft, the difference only being the designation. The Ki-84-II Hayate-Kai was Nakajima's nomenclature, Ki-84-Ib and Ki-84-Ic was the JAAF and the Ministry of Munitions designation for exactly the same aircraft. Again I think you are getting mixed up with the Ki-106.


(Also, I believe wood ADDS weight, doesn't reduce it -- you need more wood for the same strength than you would for metal of the same strength. That's why aircraft were and are made of metal. It's lighter and stronger.)

Well probably yes, it depends on the stresses involved and the type of design techniques you use to employ wood in the manufacture. If you are replacing structural trusses and bulkheads with huge wooden pieces then I would agree with you. However if you are employing layered veneers of ply to replace alloy skinning AND much of the internal structure at the same time then wooden construction might be lighter. It is nature's composite you know. It's not really worth speculating further until we have more information. It was merely an observation on my part to try to account for the considerable weight saving in the Late Production Ki-84-Ia over the Early Production version.


As far as I know only a handful of the -II were made because the engine production was moved to underground caves and productivity was very slow (also plagued with problems, as already mentioned). You are equating them as the same plane with different names, when there were really 2 separate models.

I have no data and can find nothing to suggest Nakajima moved its engine production to underground caves at any point. I do have three production lines listed for the Ki-84 with no mention of caves. Can you please substantiate your claim? For the third time, given the period of the war you seem to be suggesting, I think you are confusing the Ki-84-II Hayate-Kai with the Ki-106.


wmaker: The distinction of the gas ports is very interesting... Now that you point it out, do you have any pictures showing if any of these -Ib's saw active service? I mean photos of them with frontline squadrons, instead of derelict on a factory parking lot well after the war is over. I would very much be interested in where and how many saw actual deployment.

Thank you for uploading those pictures Wmaker!

I think I have found a picture of a cowling from a Ki-84-II Hayate-Kai, and it does indeed seem to have quite pronounced bulges. I will try to upload it later. Unfortunately it is also of a derelict.

I don't think photographs will serve to quantify the numbers of which type saw deployment. I think it best to focus on the production numbers. I have a book which JHerne shared with me showing many Ki-84s in service, I will search through it later when I have more time.

I will also try to transcribe the specifications table I have. It's just very time consuming without a scanner.
« Last Edit: October 26, 2010, 04:07:50 AM by nrshida »
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Offline Krusty

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Re: ki 84 plane set
« Reply #22 on: October 27, 2010, 11:47:18 PM »
As I've found lately, Francillon wasn't infallible. He made some mistakes. He created a new model of Betty that didn't exist, mis-labeled the squadron of planes in an apparently widely posted picture, etc.

I don't like relying on only one source... Especially if that source is given credibility because of a "grandfather clause" where it's been around the longest -- often some of the older stuff is the most inaccurate. Francillon may be nice, but he's not perfect. Might want to branch out.

As for your dispersions about my "radioactive status" I neither asked for nor looked for this, and only a fool sees a high post count as a sign of authority. I do take one small bit of pride in the fact I don't post in the O'club (where 90% of the other high posters pad their count).

Where? Where do I get this? Well you're relying so heavily on Francillon, I'd have expected you to at least read some of his writing on the matter!!!

http://www.scribd.com/doc/4661601/Aircraft-Profile-070-Nakajima-Ki84

Hint, page 8 covers several points. It also helps differentiate the -Ib as being identical to the -Ia, and the -II as being a different model with an engine change. Now, either you can accept Francillon's word, as you wanted to in your previous post.... Or you can remain skeptical in which case neither of our posts means much (both being based on Francillon) and you need to go research some more before making blanket statements like:

"Firstly no, the Ki-84-II Hayate-Kai might have had a wooden tail section but that is the extend of wood employed in this version. I'm still researching this at the moment." Well... Do you know? Or are you still researching? Not "it appears that" or "so far" but just plain blanket-statement "no, but I don't know"??

It's nothing to be ashamed of if you get the wrong designation with the wrong craft or configuration. However it's NOT a cut-and-dried issue when talking about the Japanese nomenclature.

Example:
http://78sentai.org/forum/viewtopic.php?f=3&t=33&sid=2b9e80e31c8d24e6c56c3cb1cb721317
It's about Ki-61s and Ki-43s, but it illustrates the many different ways the Japanese and the Americans referred to the same aircraft.

So it's a case of "You keep using dat word... I do not think it means what you think it means" in regards to the -Ib designation. To avoid any such issues with myself I've spelled out my words clearly enough (so I would think). There WAS a model of the -Ia armed with 4x20mm. That is what I am talking about. There WAS a revised model with a different engine, wing modificatons, and a wooden tail, and NO I'm not confusing the Ki-106. This was considered to be the -II, and the 4x20mm could be considered in US designation codes to be a Ki-84-IIb, but the similarity does not mean they were the same craft with 2 names.

You're saying the 2 names applied to the same plane. I'm saying you're wrong, and that the system was so muddled that it's a mistake many have made before you. Take the Me109/Bf109 debate and multiply it by 10, and you'll have a fraction of the issues with Japanese naming conventions.

This seems to sum it up nicely, since you don't believe anything I type :)
http://www.pilotfriend.com/photo_albums/timeline/ww2/Nakajima%20Ki%2084%20Frank.htm

"The Ki-84-II or Hayate Kai was an attempt to conserve valuable supplies of aluminum by employing large numbers of wooden components in the manufacture of the Hayate. The rear fuselage, certain fittings, and modified wingtips were made of wood, with all the wood work being carried out at a shadow factory at Tanuma. The engine was the Nakajama [Ha-45] 21, 25 or 23 with low-pressure fuel injection. Armament consisted of four 20-mm or two 20-mm and two 30-mm cannon. The designation Ki-84-II was actually a Nakajima designation, the aircraft in JAAF service retaining the Ki-84-Ib or -Ic designation, depending on armament."

If you read my previous link (japanese nomenclature) you'll see that often the pilots didn't use any of the differentiation or model numbers, they just called it a single name regardless of the model/variant. It's because of this that you're thinking the -Ib and the -II are the same. The official designations from Nakajima, the folks that designed it, suggest otherwise. Mind you I'm not an expert but I have read quite a bit about it lately. I can definitely say I don't think you have a complete picture.


Now, let's split hairs.... The Japanese fuel was limited in quality at the end of the war and the manufacturing processes on both the Ki-84 airframe and components as well as on the later-model engines was sub-par. Regardless of the fact that the designed power was higher, most of those -II with the newer engine seemed to run at reduced rates mimicking the performance of the -I. In fact, sometimes the performance was slow enough and bad enough that a Japanese pilot couldn't tell if his plane would even be able to climb up and meet the enemy. I've read a comment that some pilots thought the Ki-100 was faster. Consider that! If the aircraft failed to perform so badly that a simpler, older, airframe performs better than it. It's not the first time I've read this about late war Japanese production values in regards to other planes. In Aces High we naturally don't have such malfulnction problems. However we do model real-war performance rather than souped up US test runs. If we got any -II in-game it probably wouldn't be any different in real performance (although possibly tail-heavy -- you don't just wrap a wooden veneer to shape a tail, as the Germans did with late Fw190s you have to build the entire internal frame, ribs, braces, structures to hold the stabilizers, etc, THEN cover in fabric or wooden veneer. Often it added considerable weight as compared toe empty shells of aluminum they replaced.)
« Last Edit: October 27, 2010, 11:52:01 PM by Krusty »

Offline Krusty

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Re: ki 84 plane set
« Reply #23 on: October 27, 2010, 11:59:57 PM »
I don't think photographs will serve to quantify the numbers of which type saw deployment. I think it best to focus on the production numbers.

I think it would go a solid step towards proving the 4x20mm armament ever saw combat (that's still under question). No current references have been shown to prove this. Production numbers are one thing, and would be nice to have (numerous random sources suggest 200 give or take Ki-84-Ib models were made), but whether they sat unused at an airport or factory floor, or were used in training units, or what... these things are more important to indicate its actual impact or relevance to the war effort.

I'm currently doubtful they saw combat in any serious volume.

Offline Wmaker

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Re: ki 84 plane set
« Reply #24 on: October 28, 2010, 04:33:48 AM »
The -Ib would be identical to the -Ia but with different guns. I think you're comparing 2 different things here.

The -Ib and -Ia weren't identical. The engine models changed inside the Ia production alone. Ki-84-Ia was powered with Homare's -11, -12 and -21. My source (Leszek A. Wieliczko's Ki-84 book (ISBN: 83-89088-76-2)) mentiones -25 as one of the Ib powerplants The issue is far from being as simple as you depict it.


Hint, page 8 covers several points. It also helps differentiate the -Ib as being identical to the -Ia,

The page 8 says no such thing. I suggest you read it more carefully.


wmaker: The distinction of the gas ports is very interesting... Now that you point it out, do you have any pictures showing if any of these -Ib's saw active service? I mean photos of them with frontline squadrons, instead of derelict on a factory parking lot well after the war is over. I would very much be interested in where and how many saw actual deployment.

Those are the only ones I recall seeing. It is said that all know photographs of the Ib's are 104. Sentai aircraft.


I think it would go a solid step towards proving the 4x20mm armament ever saw combat (that's still under question). No current references have been shown to prove this. Production numbers are one thing, and would be nice to have (numerous random sources suggest 200 give or take Ki-84-Ib models were made), but whether they sat unused at an airport or factory floor, or were used in training units, or what... these things are more important to indicate its actual impact or relevance to the war effort.

I'm currently doubtful they saw combat in any serious volume.

When you have aircraft photographed that can be traced to a certain unit, it is clear that the variant was delivered during the war. The planes are in warpaint of a identifiable unit. The moment the photo was taken is actually irrelevant. Ki-84 is no different than any other aircraft we talk about in these boards. You have no evidence suggesting they weren't used. They were basically one of the best aircraft Japanese had in the end of the war. 104. Sentai operated against B-29s which was the reason why Ki-84's armament was increased in the first place. Yes, I'm sure they would have been used as training aircraft. :rolleyes:


Nrshida, here's a couple profiles of those Ib's that appear in the photos:
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Offline nrshida

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Re: ki 84 plane set
« Reply #25 on: October 28, 2010, 06:58:22 AM »
Krusty, seriously, I don't mean to be rude, but I shall in future treat your 'factual' posts with the value they deserve. I would rate your previous posts as 4/10 on the Gaston scale, and that's quite a lot of Gastonation.

You suggest we discount Francillons as a credible source of information on the strength of a few mistakes? And replace it with what? Links to forums like you have posted above for instance? A discussion from a forum, and you think this is a more credible or even an equal source to a historian and an accepted authority on the subject? Which source is likely more replete with misinformation and speculation, hardly the same thing at all is it?

I would love to have more sources, that's partly why I'm posting here to share and ask for information. I would rather have other members also sharing information from their own collections rather than playing 'Whack a Rat' with your ridiculous claims.


I believe I did read the article more carefully than you did. I read page 8 several times considering several hypotheses while I did so. If you read it in conjunction with the specification table on page 12 I think it is a credible interpretation.

You have concluded this:-

'It also helps differentiate the -Ib as being identical to the -Ia, and the -II as being a different model with an engine change.'

...from the text on the page 8, as you suggest, where it states and I quote:-

'The Army Type 4 Model 1A was followed on the assembly line by the model 1B (Ki-84-Ib) in which the synchronised machine guns were replaced by two Ho-5 cannons, thus giving the aircraft a fixed armament of four 20-mm cannons.'

Also the specification table has two distinct columns for both versions of the Ia type, both listed as having two Ho-103 12.7mm. Then there is the third column Ki-84-II, with differing dimensional information, different power units listed for all three types.

...and from this you infer the Ia was identical to the Ib?

Respectfully it is you sir, that needs to do some more reading.


I wouldn't mind so much if you weren't so condescending and certain of yourself. Please in future do not talk to me as if I am intellectually inferior or need to have things explained as if I am a child. I am fully able to comprehend what you're saying, I just disagree with you and think your opinion based approach is unsound.



Wmaker thank you for uploading those images. Have a look at this picture:-



Pretty rough I know, but does illustrate a different shape of the gun ports. I have some more line drawings which I can upload later. Would be nice if we could construct a table of the variants ourselves, using ALL of the nomenclature to avoid confusion.
« Last Edit: October 28, 2010, 07:01:33 AM by nrshida »
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Offline Wmaker

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Re: ki 84 plane set
« Reply #26 on: October 28, 2010, 12:16:35 PM »
Wmaker thank you for uploading those images. Have a look at this picture:-

(Image removed from quote.)

Pretty rough I know, but does illustrate a different shape of the gun ports. I have some more line drawings which I can upload later. Would be nice if we could construct a table of the variants ourselves, using ALL of the nomenclature to avoid confusion.

Thanks for the interesting pic nrshida!

...but I think the plane in the foreground is a Ki-43-III. ;)

It is true though that early/pre-production Ki-84s had somewhat similar pretty prominent gun ports.
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Offline nrshida

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Re: ki 84 plane set
« Reply #27 on: October 28, 2010, 02:28:42 PM »
Oh yeah I think you're right. Well spotted  :aok I was looking at the canopy and the scoop on the top of the cowl. If only the photo was a bit more complete. Do you think the gunports were the same for the Ki-84-Ia and Ki-84-II? I can't find a single picture showing a difference then.

Shame they are often wrecked in the photos. I can't help thinking, 'potential restoration project', 'potential restoration project', 'potential restoration project', lol.
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Offline Krusty

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Re: ki 84 plane set
« Reply #28 on: October 29, 2010, 12:19:58 AM »
nrshida, I purposefully adopted the condescending attitude and kept rewording and rephrasing my sentences over and over to avoid the almost total confusion you have about anything I said.

I gave you a good example. You took it to mean I had only read that one thing. I chose the one thing that should have spoken to you, by the same author you were quoting and contradicting your point. Instead you insult me. The forum link is quoting an author (on the nomenclature issues) and historian that translates primary source documents from Japanese and has his own personal collection of Allied intel reports on Japanese craft. How foolish of you to care, though... You're quite attached to Francillon.

You're far more wrapped up in composing personal insults and devoting all your time to obsessing over my post count to bother sticking to the subject matter at hand. I'll direct my comments to wmaker from this point on. You apparently don't care what I say and have formed your own notions. Just be advised my responses' tone was based on your initial comments. Golden rule. You acted like a stubborn child so I adopted a tone as one might.


Wmaker: You know better than that. You know for sure that many of the late-war monsters that the Japanese aircraft industry developed either had too many teething problems or were held back for the eventual US invasion force (to the point of creating production lines hidden in caves not just for engines but entire aircraft). The A6M7 and A6M8, the B6N Jill, the Ohka... Numerous advanced craft were BUILT but that doesn't mean they saw any appreciable service.

Take the P1Y1 Frances for example... Over 1000 built, but honestly came too late for anything but a few desperate kamikaze attacks.

It's foolish for you to say "prove they didn't" when, much like any discussion with late war Japanese or even German aircraft, the burden of proof is to say they actually DID serve.

People have been championing and requesting the 4x20mm ammo load for almost a decade now probably. In all this time nobody, anywhere, has come forward with any proof, any documents, any resources that say "Hey, this squad had -Ibs on the roster, and stopped ordering 12.7mm ammo" or "Hey, here's a picture of a fighter sweep with -Ibs" or anything of the sort. The simple fact they were CONSTRUCTED means nothing. Ask the Germans... They were building multiple hundreds of Ta-152s, had production lines set up for Do335s pumping out airframes before war's end, had He162s by the hundreds ready for pilots. Of the Tas, 12 saw service, give or take. Of the Do335s, a single plane may have been chased briefly during a test flight. Of the He162s there is only minimal proof they ever staffed a hitler youth squadron and a handful were sent out to units that had no avgas to fly them.
Or, ask the Japanese... They were stockpiling many of their most advanced weapons for use by civilian soldiers. There were numerous plans to fight to the bitter end, sacrificing hundreds of high-performance aircraft (the aircraft being stocked, only needing conscript kamikaze pilots).

So, I would very much like to see any pictures you have of the -Ib with the 20mm vents on the nose. This would be a big step towards saying "See, they were here, at least" but by no means conclusive without a lot of help. The moment the photo was taken is very relevant. Was it during a training hop? A familiarization run? Was it being used to train new pilots (phased into the fold, as it were)? The when and where of the photo can tell you a lot -- not always, but it will never hurt the discussion.


P.S. You mention the Homare engines... Forgive me if I'm blunt on this, as there's been plenty said already, but you aren't really making too fine a point with the Ha45-23 reference. Even some -Ia models had this. The only difference between the -23 and the -21 was the pressurized fuel system to keep the gas from cutting out. The down side is that they came later, and as the quality of production and performance deteriorated, the extra 100 horsepower over the models 11 and 12 was lost. Consider the same situation of the P-40E/F/M/L models. Little to no real world performance difference. Even one P-40 pilot commented not noticing any difference between the models until the P-40N.

While there is some variation in possible engines for a Ki-84-Ia, whatever the contemporary -Ia model, the -Ib would match. Even the late-production model the US captured had a Ha45-21 in it, and was still armed with 2x 12.7mm. If there was actually any proof of production, production dates, factories, etc... If there were any evidence available it would help shed some light on which production lines had which engines, and so forth. However, for a long time now folks have been making arguments hoping the Ki-84-Ib saw service. So far nobody's really shown it even existed on paper! (I'm not suggesting it is fictional, I'm suggesting burden of proof should lie with the aircraft's advocates)


Help me out on this... What is your real position on this? Are you, like nrshida, taking the position that the Ki-84-II is another name for the Ki-84-Ib? Or do you agree with me that the -II was a totally different monster, and that the -Ib matched other potential configurations of the -Ia, but you are discussing more minor differences between these two sub-types?

Offline nrshida

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Re: ki 84 plane set
« Reply #29 on: October 29, 2010, 02:17:20 AM »
Krusty: So you were condescending and I was insulting in response. Fair enough, we're even then.

I'm not obsessed about your post count, I rattled you over it once to find out what you truly thought of it and you answered. That was the one occasion I mentioned it.

No I did not take it that you only read one thing in fact. It's very clear you read from many sources in the area and that is great. What's not so great is if you form your own opinions in isolation, and then present those on the forum as 'this is the way it is', and be totally inflexible and stubborn in your opinions while you do that. That's what I take issue with. You said yourself that Francillon made mistakes. I'm sure we've all made mistakes or at least faulty assumptions reading and trying to understand descriptions and information from multiple sources.

You imply I hold Francillon in some idolatry status, this is untrue, I actually don't give a rats arse about any particular author, I'm only interested in the aircraft and the designs and engineering. I learned from contributors on this forum in fact that he was the accepted authority on the subject, and I want to find out about the aircraft. So when you disagreed with his descriptions of types, especially, I wanted to know why and if you could replace the information with better or more accurate information.

How about this Krusty, you be less condescending, I'll be less insulting, we both be more flexible in our opinions and agree to separate those from fact for the time being until we've all learned more about it. Can I say fairer than that?

As a gesture of good faith, I will not address the points you have directed to Wmaker. I'll just wait and read for now.
« Last Edit: October 29, 2010, 02:20:15 AM by nrshida »
"If man were meant to fly, he'd have been given an MS Sidewinder"