How capable was the Ki-44? (1 Viewer)

[Steamed_Banana]

Do you do these to scale, relative to each other?

 

[GregP]

Can. It's easy but takes a bit of time to make it accurate.

What did you have in mind?

 

[Steamed_Banana]

Can. It's easy but takes a bit of time to make it accurate.

What did you have in mind?

Well, nothing in particular, but I think if they were to scale you might be be able to make a book. I'd buy it! Maybe glean some data from this here forum...

 

[GregP]

I wrote one during the pandemic. It was basically drawings. The data on performance came from internet and other books, and I so stated. It was intended to show drawings of the aircraft, but one at a time, not in comparative scale. To date, not worth the cost to self publish it.

 

[SaparotRob]

.. I was surprised how huge the Swordfish is. But it's the P-47, Tempest, TBF / TBM, and Vultee Vengeance that all look so fat and oversized it's like they are at the wrong scale.
...

I stood next to an SB2C at the Royal Thai Air Force Museum. How that thing managed to get airborne amazes me. Yeah, it's got a jigunda engine, lift, thrust, taxes, drag and all that but still. Not a graceful bird to my ancient eyes.

 

[Steamed_Banana]

I stood next to an SB2C at the Royal Thai Air Force Museum. How that thing managed to get airborne amazes me. Yeah, it's got a jigunda engine, lift, thrust, taxes, drag and all that but still. Not a graceful bird to my ancient eyes.

Yes that is another "Boehemoth... "

 

[GregP]

Hey SparotRob, did I send you the clip of when we got the SB2C;s rear canopy working?

Can't remember. Just checked and, yeah, I sent it.

Anyway, the early bird were a bit underpowered, but the later models got 1,900 hp from their R-2600s, and they were quite sprightly.

 

[Steamed_Banana]

Hey SparotRob, did I send you the clip of when we got the SB2C;s rear canopy working?

Can't remember. Just checked and, yeah, I sent it.

Anyway, the early bird were a bit underpowered, but the later models got 1,900 hp from their R-2600s, and they were quite sprightly.

I'd love to see one flying.

I think the main problem with that bird was due to the fuselage being a bit too short for the whole big beast of a plane, apparently due to somebody in the Navy or War Dept insisting that two needed to fit on one CV elevator

 

[Steamed_Banana]

Big planes / little planes. All in 1/72 scale.

Top row left to right: Macchi MC.202 fighter , Ki-43-II "Hayabusa" / Oscar, Yak-3, SB2C "Helldiver" dive bomber, P-47D "Thunderbolt" fighter (early)
Bottom row, left to right: Ki-44 "Shoki" / Tojo, Dewoitine D.520, Vultee A-31 "Vengeance" dive bomber, Hawker "Tempest" fighter, Fairy "Fulmar" naval fighter

 

[Airborne2001]

View attachment 850523

View attachment 850525

Big planes / little planes. All in 1/72 scale.

Top row left to right: Macchi MC.202 fighter , Ki-43-II "Hayabusa" / Oscar, Yak-3, SB2C "Helldiver" dive bomber, P-47D "Thunderbolt" fighter (early)
Bottom row, left to right: Ki-44 "Shoki" / Tojo, Dewoitine D.520, Vultee A-31 "Vengeance" dive bomber, Hawker "Tempest" fighter, Fairy "Fulmar" naval fighter

The only aircraft that truly has an almost exact wing size to the Ki-44 is the Yak-3, althought the latter is a very light design that is also a tad bit smaller. So the design definitely had small wings. Wing loading was definitely gonna be a bit high, but again for the interceptor role maneuverability wouldn't matter quite as much. How was the climb rate?

 

[Steamed_Banana]

The only aircraft that truly has an almost exact wing size to the Ki-44 is the Yak-3, althought the latter is a very light design that is also a tad bit smaller. So the design definitely had small wings. Wing loading was definitely gonna be a bit high, but again for the interceptor role maneuverability wouldn't matter quite as much. How was the climb rate?

Climb rate was very good, it was good for that interceptor role no doubt. And enough guns to wreak some havoc on a lot of allied bombers... like a Havoc.

 

[SaparotRob]

Hey SparotRob, did I send you the clip of when we got the SB2C;s rear canopy working?

Can't remember. Just checked and, yeah, I sent it.

Anyway, the early bird were a bit underpowered, but the later models got 1,900 hp from their R-2600s, and they were quite sprightly.

Yes I did. They are in a secure location.

 

[GregP]

I'd love to see one flying.

I think the main problem with that bird was due to the fuselage being a bit too short for the whole big beast of a plane, apparently due to somebody in the Navy or War Dept insisting that two needed to fit on one CV elevator

here you go ...


View: https://youtu.be/WPLrbSqoRgc

 

[andrewgeorge]

Well maybe that's a discussion for another thread, but I don't necessarily agree that a Hellcat is going to out-turn a P-40, P-40s also had flaps which could be used at maneuver settings (manually) and I think Corsairs are fairly close to a Hellcat in turning circle though I haven't looked at it in a while. I'm not too concerned about it either way.

Pretty sure P-40 would have been at least as tight turning as a Ki-44. Ki-44's big advantage vs most of the allied types (P-40, P-48, P-47, P-51, etc) it encountered wouldn't have been its maneuverability so much as its power-to-weight. Acceleration and climb.

 

[andrewgeorge]

Japanese pilots respected the Hellcat far more than the Corsair or P-38 because it specifically was capable of keeping up enough in a turn to still shoot them. It also had the largest wing area of any single engine WW2 fighter.

From what I've read, the Japanese were of the opinion that the "Grummans" were generally superior to their own late-war types (J2M, N1K, Ki-84, etc.) in turn rate. Their main advantage would have been in power-to-weight. Using altitude and the vertical. They cautioned against turnfighting F6Fs in their newer fighters.

 

[Irregualr23]

Agree, the efficiency of the wing, which is I guess (?) CL Max, and the power also matter - and this would of course vary by altitude.

One other factor regarding rolling, both the A6M and the Bf 109 allegedly got very tight for roll at higher speeds (edit: Specifically for turning in one direction, i.e. due to torque which I think was right in both cases though I might be wrong. Luckily I'm not going into combat against one of these!). How much this mattered seems to be one of those endlessly debated things, but Allied pilots seemed to be aware of this by later in 1942 and relied on it to escape pursuit quite routinely. This was addressed somewhat in the A6M3 and later with the clipped wings. Trim tabs alleviated this in some US types.

The Ki-43 was limited in dive speed but apparently didn't have this locking up problem, and since Allied pilots often could not tell the difference between A6M and Ki-43, this was a problem in areas like New Guinea where they routinely encountered both types.

Speaking of CLmax, the US Naval Fighters tends to use wings with no inherent twist angle( no geometric washout under static condition). The incidence angles are the same from the wing-root to the tip. This gives sharper stall near the critical AoA but larger CLmax. Combining with larger MAC gives larger Reynolds' Number, and larger propeller slipstream, the F6F was able to obtain a CLmax 1.47-1.52 under clean condition, power-off with propeller idling. The stall characteristic is compensated by larger dihedral effect from the wing (trading roll-response), and by aeroelastic effect(under the air load, there will be twist on the wing). The F4U in similar design stalls 2 degs earlier possibly due to its wing-ducts, reduced its CLmax under similar condition to 1.37-1.42 (0.1 lower than the Hellcat, according to the Langley report 829).

The larger CLmax gives considerable advantage in instantaneous turn performance under similar wing-loading. The higher than average CLmax of the F6F gives it slight advantage in turn-radius compared with Japanese fighters with similar wing-loading figure ( Ki-44, Ki-84, J2M and N1K). Another example would be the P-38, it uses similar NACA23000 airfoil along the wing with no-twist, with an aspect ratio of 8 gives it very high lift-coefficient, thus it has smaller radius of turn comparing with P-47 and P-51 even though its wing-loading is significantly higher.

The Japanese design tends to optimize wing twist under static condition, they usually design the wing with specific twist-angle at each specific span position. It may be optimal under level-flight but can be sub-optimal under heavy air-load during a manoeuvre. Twist angle as high as -3.5deg was used on the N1K Shiden. Combining the fact that Japanese fighters are having smaller MAC, give the Japanese fighters a usual CLmax figure lower than 1.4. Exceptions were Ki-61 and A7M which has CLmax greater than 1.4.

Speaking of flaps, the American fighters tend to have larger flap span, but simpler flap design. The Japanese fighter tend to have smaller flap span but more complicated flap design. Ki-43/44/84 and J2M are equipped with Fowler flaps, N1K and A7M are equipped with double-slotted flaps, and they can be deployed to give better L/D than conventional slotted flaps on the American fighters, but the overall lift is lower due to smaller affected area.

F6F has around 60% span for 4 pieces of extensible-slotted flap and they provide more lift and less drag compared with F4U's hinged slotted flaps. Both aircraft are very good at using combat flaps.

Estimated power-off CLmax comparison ( Clean / Full-flaps)
F6F: 1.5 / 2.1
F4U: 1.38 / 2.0
Ki-44/84: 1.35 / 1.9
Ki-61: 1.44 / 2.12

 

[beers]

I don't really understand the relative advantages of split, full (per above) and fowler type flaps for combat maneuvering, but I think both Ki-43 and the P-38 had the fowler type.

There's quite a few flap types and then you have the grey areas between them like with Simple and Slotted type. But when it comes to japan, they really liked Fowlers since they boosted maneuverability by a lot and the ones not using them make a shorter list than otherwise.

Ki-44 indeed had Fowlers and this was seen as a necessity both for reducing takeoff/landing speeds and to help its maneuverability. Coming from the Ki-27, flying a Ki-44 without them would have been a nightmare. Even with those it wasn't great and eventually Nakajima wanted to extend the wings and increase the tail controls' surface.

 

[beers]

From what I've read, the Japanese were of the opinion that the "Grummans" were generally superior to their own late-war types (J2M, N1K, Ki-84, etc.) in turn rate. Their main advantage would have been in power-to-weight. Using altitude and the vertical. They cautioned against turnfighting F6Fs in their newer fighters.

Instant turn rate, I 100% believe that. If the fight was prolonged, the Hellcat is a heavy girl and I don't think it has the power to sustain that for very long at all. Apart from maybe the Ha-45 -equipped planes that were likely detuned and it's harder to figure out exactly what they performed like, a sustained fight would have been extremely dangerous. A Ki-44 has a lot of power for its small frame.

Wasn't there a J2M ace who would constantly enter dogfights in it whenever possible?

 

[GregP]

Speaking of CLmax, the US Naval Fighters tends to use wings with no inherent twist angle( no geometric washout under static condition). The incidence angles are the same from the wing-root to the tip. This gives sharper stall near the critical AoA but larger CLmax. Combining with larger MAC gives larger Reynolds' Number, and larger propeller slipstream, the F6F was able to obtain a CLmax 1.47-1.52 under clean condition, power-off with propeller idling. The stall characteristic is compensated by larger dihedral effect from the wing (trading roll-response), and by aeroelastic effect(under the air load, there will be twist on the wing). The F4U in similar design stalls 2 degs earlier possibly due to its wing-ducts, reduced its CLmax under similar condition to 1.37-1.42 (0.1 lower than the Hellcat, according to the Langley report 829).

The larger CLmax gives considerable advantage in instantaneous turn performance under similar wing-loading. The higher than average CLmax of the F6F gives it slight advantage in turn-radius compared with Japanese fighters with similar wing-loading figure ( Ki-44, Ki-84, J2M and N1K). Another example would be the P-38, it uses similar NACA23000 airfoil along the wing with no-twist, with an aspect ratio of 8 gives it very high lift-coefficient, thus it has smaller radius of turn comparing with P-47 and P-51 even though its wing-loading is significantly higher.

The Japanese design tends to optimize wing twist under static condition, they usually design the wing with specific twist-angle at each specific span position. It may be optimal under level-flight but can be sub-optimal under heavy air-load during a manoeuvre. Twist angle as high as -3.5deg was used on the N1K Shiden. Combining the fact that Japanese fighters are having smaller MAC, give the Japanese fighters a usual CLmax figure lower than 1.4. Exceptions were Ki-61 and A7M which has CLmax greater than 1.4.

Speaking of flaps, the American fighters tend to have larger flap span, but simpler flap design. The Japanese fighter tend to have smaller flap span but more complicated flap design. Ki-43/44/84 and J2M are equipped with Fowler flaps, N1K and A7M are equipped with double-slotted flaps, and they can be deployed to give better L/D than conventional slotted flaps on the American fighters, but the overall lift is lower due to smaller affected area.

F6F has around 60% span for 4 pieces of extensible-slotted flap and they provide more lift and less drag compared with F4U's hinged slotted flaps. Both aircraft are very good at using combat flaps.

Estimated power-off CLmax comparison ( Clean / Full-flaps)
F6F: 1.5 / 2.1
F4U: 1.38 / 2.0
Ki-44/84: 1.35 / 1.9
Ki-61: 1.44 / 2.12

The Vought F4U corsair primarily used an NACA 2415 airfoil. Typical CL Max for a 2415 is 1.55 to 1.75. I'd be surprised if they let it deteriorate to 1.38, but I have not researched it, either, so you could be correct. Seems like something for an interesting evening (or longer) investigation .

Cheers.

 

[tomo pauk]

The Vought F4U corsair primarily used an NACA 2415 airfoil.

F4U used NACA 230 series.
18% t-t-c in the root, 9% on the tip.
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