The Kawasaki Ki-100 with an air-cooled inverted V-12 engine.

[Ivan1GFP]

Hello K5083,

The Ki-100 wasn't a 1941 fighter and for that matter, neither was the Ki-61. Officially it was the "Army Type 3 Fighter" because of its introduction in 1943 just as the Ki-100 became the Army Type 5 Fighter because of 1945 introduction.

I personally would rate the Ki-100 as superior to a Spitfire V and P-40 in any model. The Ki-61-I on the other hand would be somewhat inferior to both because it was a fairly heavy aircraft without much engine power. Level speed was fairly close, but climb rate was fairly poor.

Regarding airflow for an air cooled inverted V-12. I figure the same arrangement as a P-40 should work.

- Ivan.

 

[spicmart]

Google Curtiss XP-42 and Vultee Vanguard. Both started with a special R-1830 with an extended propshaft. You probably won't find all the photos but the XP-42 went through 14 different cowl configurations. At least one of them may have used a fan in a narrow slot (big spinner).

The early J2m was also supposed to use an extended shaft and a very pointy nose. In addition to cooling problems both the Americans and Japanese ran into prop vibration problems with the extended shafts.

Both look very sleek. One would assume that they were faster than other configurations. So did I understand right that these spinner only were a failure because of the longer propshaft they required?

 

[swampyankee]

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Both look very sleek. One would assume that they were faster than other configurations. So did I understand right that these spinner only were a failure because of the longer propshaft they required?

They only look sleek. Cooling drag comes from needing to slow the air down and have it flow by a lot of surface area, so there is s lot of energy lost to surface friction. A pointy nose doesn't solve that, nor does a liquid cooling loop.

 

[spicmart]

They only look sleek. Cooling drag comes from needing to slow the air down and have it flow by a lot of surface area, so there is s lot of energy lost to surface friction. A pointy nose doesn't solve that, nor does a liquid cooling loop.

I seem to recall that the German spinners which were rather curvy than pointy to achieve better cooling current. This is especially obvious with the annular/drum radiator config.

 

[Shortround6]

Both look very sleek. One would assume that they were faster than other configurations. So did I understand right that these spinner only were a failure because of the longer propshaft they required?

They only look sleek. Cooling drag comes from needing to slow the air down and have it flow by a lot of surface area, so there is s lot of energy lost to surface friction. A pointy nose doesn't solve that, nor does a liquid cooling loop.

they had problems getting the air from the scoops at the bottom of the cowl to the cylinders at the top of the cowl. for a radial to work well you need fairly even temperatures in all cylinders. The hottest one/s are going to give trouble first. SEE R-3350s in B-29s most of the engine failures were from just 3 out off the18 cylinders.

It doesn't matter how slick the plane is if you can't run the engine at full rated power for several minutes without the temp gauge going into the red zone.