Posted 07 December 2006 - 02:20 AM
Posted 07 December 2006 - 04:26 AM
496 for dive speed. Not so great, but 45 vintage ones might've been better.Dunno.
Posted 07 December 2006 - 04:31 AM
Out accelerate? Possibly but usually not. The Hayate's engine had serious problems developing full power for a large number of reasons including:
Poor fuel pump pressure development and inconsistant fuel delivery.
Cracking of the exhaust manifold
Cylinder head failures and cracking
Climb? The Ki 84 outclimbs late model P-47s slightly. It is about equal to the P-51.
Break off combat? Not likely. Under most conditions the Ki 84 is anywhere up to 50 knots slower than late war US fighters. It also has less range. High altitude performance in particular suffers, particularly above 25,000 feet. This last problem is endemic of Japanese aircraft due to lack of good turbo / super-charging systems.
Against USN aircraft the Ki 84 might have more of a chance to break contact.
Personally, I think that Kawanishi's N1K2-J Shiden Kai fighter is better. In one rather spectacular dogfight one of these fighters flown by Warrant Officer Kinsuke Muto of the 343rd kokutai took on tweleve (12) F6F Hellcats shooting down 4 and fighting the rest to a draw forcing them to break contact. Like the Ki 84 the N1K2 suffered a big performance drop above 25,000 feet or so.
Posted 07 December 2006 - 04:36 AM
Break off combat? Not likely. Under most conditions the Ki 84 is anywhere up to 50 knots slower than late war US fighters."
Much superior to Mustang in climb. & faster than 47 & Stang at most altitudes, execpt up high where most pacific combats did not take place.
Frank climb,Rate of climb: 19.25 m/s (3,790 ft/min)
Mustang D 3200 ft per min.
Posted 07 December 2006 - 04:41 AM
Posted 07 December 2006 - 04:43 AM
Direct injection the likely suspect for outacceleration.
Much of its superlative all-round performance stemmed from its extremely advanced direct-injection engine, the Army's first version of the Navy NK9A.
Posted 07 December 2006 - 04:48 AM
Range on internal fuel 1,025 miles (1,650 kilometres)
Range with 98-gallon drop tanks 1,815 miles (2,920 kilometres)
Mustang B 730 miles range
Combat range: 950 miles
Operation range with drop tanks: 1300 miles
Posted 07 December 2006 - 04:55 AM
Range: 1,650 mi (2,655 km) with external tanks
The Frank had its technical problems no doubt, but material shortages account for most of it, not bad engineering or poor design.
Posted 07 December 2006 - 10:13 AM
Cant see how it 's better tha the P-51D, though like all aircraft in the hands of experts it is possible that they outfought them, and other Allied fighters, from time to time.
But I've got a max rangeat 1347miles for the Ki-84-1a and 2080 miles for the P-51D. Top speed of 392mph v 437mph for the P-51D. Th P-47N could also travel around 2000 miles and had a top speed of 467mph
Posted 07 December 2006 - 10:16 AM
But I think the Ki-84 was much more reliable than any other Japanese late war fighter like Ki-100 or the Georges, and did not suffered much teething problems although they indeed often had some fuel pressure failures (and shared the fragile "legs" of the Georges).
It was very well armored, which was a big step forward for Japanese design.
It was used in numbers and had good combat accounts, thanks to high performance, strong guns and good maneuverability which was important in the Japanese way of dogfighting and also given the poor average training of late war Japanese pilots. Production standards obviously collapsed overtime under the US air raids pressure.
Overall it is very easy to have a good idea of its performance and horizontal maneuverability : pretty much the same as the F4U Corsair at all altitudes, which means faster than the Hellcat, much more maneuverable than P47 and P 51 (late D versions), as fast as the P47 under 5-6000m, slower than the P51, especialy at medium and high alt and than the P47 above 5-6000m.
Posted 07 December 2006 - 10:04 PM
Mustang had better dive & better high altitude performance, but again most pacific theater combats were not high altitude except B-29 raids. So Mustangs high altitude performance has to weighed with that in mind.
So with better accelaration & climb as well as manoeuverability & superior power to weight ratio by a mile, one can make the claim it was better than Mustang. Better range to boot.
P-47 M too little numbers & too late in war to make fair comparison. Not sure on 47 N.
Posted 07 December 2006 - 10:11 PM
The P-47N was designed for very long range operations in the Pacific escorting B-29s. A P-47N fully loaded with 5" HVAR rockets, bombs and up to 710 gallons of fuel in external tanks weighted nearly 21,000 lbs., heavier than any other single engine fighter of World War II. The P-47N on display was built in 1945 and is painted in the colors of 1st. Lt. Oscar Perdomo of the 507th Fighter Group in the Pacific during the final days of World War II. Perdomo shot down five Japanese aircraft on the last day of WWII making him the last "Ace in a Day" of WWII.
This version actually received several designations, but in order to prevent confusion with the Ki-84-Ib and Ki-84-Ic (depending on armament), the Ki-84-II designation or even Hayate KAI was used.
Previous versions suffered from sudden fuel pressure loss, and the problem was only solved with a development of the Ha-45 21 that had low-pressure fule injection. This version, designated Ha-45 23, was never produced in the numbers of it's predecessor, because the plant where it was built had been bombed, and was replaced to an underground installation.
The Ki-84-II was built with either one of the following poerplants: Nakajima Ha-45 21, Nakajima Ha-45 25 or Nakajima Ha-45 23 radials.
Another new feature was the wooden rear fuselage, certain fittings and modified wingtips. Shortages of aluminium prompted the Japanese to resort to wooden parts in stead.
Here is some comment on the fowler flaps on Frank. Another interesting feature I'd like to know more about.
About maneuverability, though Ki-84 had "Butterfly-Type" Fowler Combat Flap, it had heavy nose especially when fowler flaps are full open. In TnB, it would be disadvantage against N1K2 (btw USA reported Ki-84 out-maneuvered Spitfire).
Posted 08 December 2006 - 05:28 AM
Perhaps it comes down to which was more robust. Frank was not as robust as allied types & could not handle as heavy of G's.
Posted 08 December 2006 - 11:25 AM
- I forgot to mention my comparisons above with P47 are based on late D versions, not N versions,
- P51D was faster at any alt, except a in a very small fork (due to supercharger stage switch I guess-to be checked) in the med-high alt. If Ki-84 used war emergency power, the P51D was still faster, but by a smaller margin (I'm talking about Ki-84 Ia using standard Japanese fuel). Of course, this can vary according to some factor like how much fuel is carried etc etc.
BTW it is a widespread myth that P-51 was a snail at low alt.
- Ki-84Ia and F4U1-D turned just the same (low alt that is) up to 350 kph, at faster speeds, Ki-84 turned very slightly better but the margin is so small it's not worth mentionning. It's in the clean configuration, with flaps down, the Ki-84 took the upper hand and the more the flaps are down, the better is the Ki-84 compared to the F-4 (but I doubt a late war corsair pilot would follow in a furball dogfight )
- climb rate : (I mean max rate of climb) the Ki-84 climbs pretty much the same as the above corsair, at all alts, at all alts, especialy med and high alt, it had a better max climbrate than the P-51D, and better than the P47D (late versions) up to 8.000m.
- I'll compare with the Georges later on.
Posted 08 December 2006 - 05:29 PM
Posted 08 December 2006 - 11:23 PM
Of course Japanese gas & oil were not of same quality as US, so that has to figured in, but bench test, Frank is faster.
Posted 11 December 2006 - 10:12 AM
About this test, I find no data about low and medium altitude speed, only a 427 mph at 20.000 feet, and neither I know if the tested Frank was a Ia version and what engine it carried.
Have you got a link toward a comprehensive report of this test, especialy the speed reached by the Frank at low or medium alt ?
Because 20.000 feet is not a low altitude and it's right into the altitude fork where the P-51D (D-20) had a weakness due to supercharging staging (I believe) and was the very peak of the Ki-84Ia top speed, therefore I won't draw conclusion on this sole altitude.
Here we go
Altitude / P 51D20 speed / Ki84 Ia speed(meters / kph – metric system rules ! ) : no war emergency power
1000 560 / 520
2000 605 / 550
3000 630 / 560
4000 655 / 570
5000 645 / 600
6000 630 / 630
7000 650 / 645
8000 680 / 630
Now, let's tighten the fork to the only altitude range where the Ki-84Ia (war conditions) could compete with the P51-D, the 5.000 – 8.000 m range, at "all out" speed (which means "overboost", war emergency power etc etc)
5.000 665 / 660
6.000 660 / 685
7.000 690 / 680
8.000 700 / 670
As you can see, these numbers are pretty much on par with the above mentionned bench, rating the Frank at 427 mph @ 20.000 ft, but still the P-51D is faster at low alt (below 3.000m and medium alt (3.000 – 6.000 m).
Posted 13 December 2006 - 06:36 AM
"In fact, the "Hayate" was good enough to best the P-51B and D Mustangs operated by the 23rd Fighter Group, and managed to establish air superiority over China during the last Japanese offensive of the war that fall."
Pretty much every site on the Frank echoes this...
The Frank has a 1900 horsepower Homare engine in an airframe more than one ton lighter than the Corsair. This gives the Frank excellent speed - faster than even the Mustang at low altitudes
It's lightweight is another factor to weight in on the acceleration issue.
Posted 13 December 2006 - 06:47 AM
There are a few differing views on Franks speed covered here.
I have a copy of a translation of a captured document (hand written notes) of unknown reliability which indicates two maximum speeds for the Ki 84-1 (Light) and Ki 84-1 (Improved). The two speeds apparently relate to the Ha 45 rating of 2000 hp at 1500 meters and 1800hp at 6000 meters.
Ki 84-1 (Light) 664 kph (=412 mph) and 693 kph (=430 mph)
Ki 84-1 (Improved) 658 kph (=409 mph) and 688 kph (=427 mph).
Fully equiped wgt of Light = 3576 kg; Improved = 3858 kg
During the war TAIC rated Ki 84's max speed at 422 mph.
There are many instances when Japanese "official" figures are less than US tests and observed combat performance.
Posted 13 December 2006 - 12:57 PM
This has to be a joke.
this is (no war emercency power or overboost):
- about 60+ kph faster than the P51D20 or the P 63 kingcobra, Yak3, Yak 9U, La-7
- more or less 100 kph faster than the Bf 109K or FW 190D, or Spit IX (with 25 lbs boost), or Tempest Mk V
- even at war emergency power, the above planes can't compete and are in most of the case far behind
I know one has to makes some guesstimations about Japanese planes performance, but I consider 664 kph @ 1500 m is a ridiculous claim.
And don't give too much credit to this US bench, otherwise, you'll have to give also credit to the RAF bench which had for result the seafire LIII being faster than the Ki-84 on the deck (I stillo wonder in what shape was the Frank tested by the RAF )
Posted 15 December 2006 - 01:33 AM
Posted 16 December 2006 - 02:19 AM
I have a vague recollection of a Japanese pilot who had 13-14 Mustangs in his bag. But Japanese scores are hardest of all to verify.
Posted 16 December 2006 - 06:40 AM
& just to add to the confusion, it seems the Frank had 4 powerplants.
Ki.84-I Hayate "Frank"
Single engine fighter
The following engines were used by the Ki.84-I as availability permitted:
Ha-45-11, rated at 1,800hp for take-off and 1,650hp at 6,560ft.
Ha-45-12, rated at 1,925hp for take-off and 1,670hp at 7,875ft.
Ha-45-21, rated at 1,990hp for take-off and 1,850hp at 5,740ft.
Ha-45-23, rated at 1,900hp for take-off and 1,670hp at 4,725ft.
Posted 16 December 2006 - 06:51 PM
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