Kawasaki KI 61 Hien "Tony"

[eagledad]

A most Prosperous New Year to All!

I believe that only about 100 Ki-61 - II were built. There may have been 350+ airframes built, but with only 100 Ha-140 engines built, the JAAF couldn't have more Ki-61-II's than that. The extra Ki-61-II airframes were mated with the Ha-112 radial engine and became the Ki-100.

May God Fly your wing always!

Eagledad

 

[FLYBOYJ]

A most Prosperous New Year to All!

I believe that only about 100 Ki-61 - II were built. There may have been 350+ airframes built, but with only 100 Ha-140 engines built, the JAAF couldn't have more Ki-61-II's than that. The extra Ki-61-II airframes were mated with the Ha-112 radial engine and became the Ki-100.

May God Fly your wing always!

Eagledad

In 1944 the Ki-61-II was being built, but was only trickling off the production lines, and was suffering from the unreliability of its engine. Moreover the engine was not being produced in sufficient numbers. The initial version of the -II had a larger wing and a new canopy, but it was soon replaced by the -IIa with the older and proven wing. Only 374 of all variants of the -II were built.

In early 1945 one of 275 engineless airframes was fitted with the Ha-112 radial engine. Although a sudden lash-up conversion this produced a staggeringly fine fighter, by far the best ever produced in Japan. This aircraft, designated the Ki-100, was put into production with desperate haste. One of the first Ki-100 units destroyed 14 F6F Hellcats over Okinawa in their first major encounter - without loss to themselves. The easily-flown and serviced Ki-100 fought supremely well against Allied fighters and B-29 bombers to the very end of hostilities in the Pacific.

Kawasaki Ki-61 "Tony" - Japanese fighter aircraft

 

[alejandro_]

Hello all

I am doing an analysis of Ki.61 performance with respect to other fighters in early 1943, when the Hien was deployed. The graph below shows the seed. would anyone like to comment on it? suggestions, modifications, corrections...

Data are from:

- Íîâàÿ ñòðàíèöà 1 (Soviet tests at NII VVS)
- The P-38 Lightning (P-38 with 1125HP engines)
- P-47 Performance Tests (P-47 at 56" and Hamilton-Standard propeller)

 

[timshatz]

Nice post alexandro. Just a thought, maybe you should use the numbers for a P39D or somewhere close instead of the Q. I seem to recall the D was the model used in New Guniea and the Q probably didn't see much work against the Tony (although it was probably the model in production at the time of the Tony's time).

 

[Shortround6]

You may be right. At least the M/N models may be in the area in the summer of 1943.

 

[alejandro_]

Thanks for your messages.

I have look for variants used by USAAF in Guinea nd I got P-39D/F/Q as well as P-400, but I would need speed-altitude diagrams for them.

 

[muscogeemike]

A most Prosperous New Year to All!

I believe that only about 100 Ki-61 - II were built. There may have been 350+ airframes built, but with only 100 Ha-140 engines built, the JAAF couldn't have more Ki-61-II's than that. The extra Ki-61-II airframes were mated with the Ha-112 radial engine and became the Ki-100.

May God Fly your wing always!

Eagledad

This Ki-100 was reportadly a very good aircraft.

 

[windswords]

The Ki-100 was said to be much more reliable and easier to fly than it's Ki-61 brother. So it was good for pilots with little training compared to what they got earlier in the war. It had good maneuverability and acceleration at low and medium altitudes. It did not have a high speed and could not function well at the heights the B-29's flew.

 

[Ivan1GFP]

I haven't researched this aircraft for quite some time, but here goes:

The time of the Ki-61-I is pretty much from about the beginning of 1942. One attempted an intercept of the Doolittle Raiders in 1942.

The Japanese recorded maximum speeds with Military power and not War Emergency Power, so I suspect most of their planes were a bit faster than what is generally recorded. The -I version had too little installed power. Consider it pretty similar to a Me 109E/F.

The -II was assumed by TAIC to be 400+ mph which is reasonable considering the airframe and installed power. Consider it at its best to be fairly similar to a Me 109G. The big issue was that the Ha-140 engine was never reliable. Although the Ha 112 radial installed to make the Ki-100 was only +50 HP, it was one of the more reliable J engines and lived up to claims while the Ha-140 didn't. It was also several hundred pounds lighter (minus the cooling system) but a lot slower because of the radial drag.

- Ivan.

 

[tomo pauk]

Hi, Ivan, perhaps you'd be kind to answer some questions:
When we read eg. Homare have had 1900 HP, was that MIL or WEP?
What was measured power, when engine(s) were tested by Allied institutions during/after WW2?
What kind of fuel was Japan using, to achieve those 1900 HP?

Thanks in advance

 

[Ivan1GFP]

The last question is easy: Japanese Aviation fuel was 92 octane. I have seen one article that mentioned that fuel drained from captured aircraft at one location tested a bit higher than that. I did not understand the significance of that article when I encountered it years ago and didn't save it.

I don't have any notes here at work, but Google to a reliable source (NASM) tells me that 1990 HP was Take-Off or WEP at +500 mm. The other ratings are also specified here but beware that it is Metric HP. Keep in mind also, that the throttle settings and HP ratings differ a bit depending on the installation and model of the engine.

NASM Research 4

I believe there are some engine test results with the famous Ki-84 that performed so well.

Consider that the typical Homare engine didn't perform all that well. It was poor enough that the Japanese considered replacing a nominal 2000 HP (Ha-45) engine with a nominal 1500 HP (Ha 112) engine even for the Ki-84. These folks were in some serious trouble as far as general reliabilty of anything at this stage of the war.

- Ivan.

 

[alejandro_]

I have been looking at the Ki-61 range given in various books and reports. There is quite a bit of variation:

- According to US reports* (TAIC manual): ~1.500 miles with internal fuel (199 US galons) at 155mph.
- Vectorsite: 1.120 miles.
- Osprey duel P-38 Lighting vs Ki-61 Hien, by Donald Nijboer : 373 miles.
- Wikipedia (reference: Japanese aircraft of the Pacific War): 360 miles

Wikipedia and Osprey are too low as Ki-61 carried almost twice as much fuel as a Bf-109/Spitfire. TAIC manual gives the most accurate data. Any opinions?

Can be found in: http://www.ww2aircraft.net/forum/aircraft-requests/ki-61-tony-speed-altitude-diagram-27545.html

 

[renrich]

From a little gem of a book which I have had almost forever, "Aircraft of World War Two," by Kenneth Munson, published in the US in 1968, price brand new, $4.50. The Tony had a lightweight Japanese adaptation of the German DB 601 called the HA40 putting out 1175 HP and originally used the Mauser MG151. When the German guns became scarce, Japanese built 20 mms were used. The KI61-1D had 30mm wing guns. The KI61-II was to be powered by the 1500 HP HA140 but only eight were built. Supply of engines critically short.

Vmax was 348 mph at 16400 feet, service ceiling was 32800 feet, max range was 1185 miles(yardstick), armament was two 20 mms and two 12.7s, weight empty was 5798 Lbs.
Above was the KI61-1c

 

[tomo pauk]

A 'yardstick' range (flying from point A to point B, at best altitude, at cruising speed) of 1200 mi returns roughly 400 mi of combat range (flying @ cruising speed, 15 min @ MIL, 5 min @ WEP, return to the same airport),. So I'd guess the sources from posts directly above are not in disagreement.

 

[CORSNING]

Hi Guys,
Guynemer,
I just stumbled onto this Thread. There is some great information on WWII Aircraft Performance on the Ki-61-I. Somewhere on this sight I also stumbled across what appears to be a TAIC report numbered 154A and 154B. It is titled TONY 1 and TONY 2. It states that the performance figures for the Ki.61-II are based on fragmentary documentary evidence and resultant extrapotation of engine ratings (I wish I knew exactly what all that meant.?). It has perfomance graphs. The following is from 154B 1-4.
Engine: Kawasaki Ha-140/1,440hp @ WE power/5,700ft.
Test Weight: 7,232 lbs.
Maximum Speed: 335mph/S.L. 423mph/28,000ft.
Climb: 3,425fpm/S.L. 3,560fpm/6,600ft. 1,000fpm/37,400ft. 100fpm/43,000ft.
Timed Climb: 10,000ft./3.2min. 20,000ft./6.6min.
Maximum Range: 2,120mls./150mph./1,500ft./305gallons of fuel.
I see this Thread started in December 2006 so you probably have all this information. But just in case you didn't. I thought I'd throw it out there. If you haven't seen this report, let me know and I'll try to break the graphs down more and post info on the Tony 1 as well.
I read on Wikipedia that the Ki.61-II was one of the very few Japanese fighters able to reach the operational altitude of the B-29s raiding Japan with decent firepower. Wiki contenues stating the majority of B-29s lost to Japanese fighters were shot down by the Ki.61-II. Well, that's what Wikipedia says.

 

[davebender]

Not sure what you are measuring. It's my understanding the Ki-61 carried 545L of internal fuel. That's similiar to the German Fw-190.

 

[cherry blossom]

There is a discussion of the Ki-61 range at KI-61 Hien Range? with lots of information. Briefly, the fuel tanks got smaller as the self sealing or armour got thicker, especially the wing tanks as the wings could not expand.

 

[CORSNING]

Guys,
Finding this report is fairly new to me. On page 154B-2 it states that internal fuel of the Ki.61-II is 199 US gallons and with external drop tank(s) of 106 US gallons it comes to 305 gallons. Maximum range is 2,120 mls. under the conditions I have (they have) stated. This report is dated March 1945. I will gladly list the performance figures on the graph. I just wasn't sure if anyone was still interested in this thread.?