Ki-51(Nichimo 1/48) WIP #1


These are the photos that my grandfather owned when he was alive.

My grandfather Kingo Inoue(2nd from the right on the photo) was a test pilot of Mitsubishi Heavy Industries, and was the test pilot for the first flight of IJA Ki-51(Sonia).
These photos above show the flying Ki-51 prototype and the smiling pilots with Mr.Kariya Masai from “Kugisyou”(Japan Aero Technology Laboratory) at the left-end, just after its first flight in 1939 at Gifu Airbase.

As seeing the photos, I gradually had become to want to have the plane in my hand closely.
Around in 2007, I bought and almost built the Nichimo’s kit of Ki-51. It’s an old but good kit with details even inside, though it couldn’t satisfy me enough. So I decided to reproduce the plane as completely as possible.

After a bit thinking, I scraped away all the molds inside the fuselage, and started to attach beams with plastic rod materials one by one.
But I didn’t know that it was just a first step of the long journey for building the plane for about up to two years and a half.

After some struggles, I completed the beams work. But it took about six months !

Next, I went to the cockpit panel, the radio and accessories.
Designed as a reconnaissance plane, Ki-51 had a many windows even beside the control stick.

The radio included in the kit was quite different from the real one, so I scratch-built it.


Gunner seat


Meter panel for second office. The upper is of the kit, and the lower is my work out of junk materials. You can see the control stick on the right.


Aileron pedals.


Ki-51 had a characteristic single flap on the center of the main wing.
After cutting off the flap, inside-panel attached.

The engine of the kit was not bad, but it should be more realistic. I scraped away the molds as cylinder rods, and started to build engine.


Left: kit  Right: my work


Atached the bundled 0.3mm plastic round rods as molds for cylinders surface.


At that time, I occasionally got a micro motor. I tried to insert it into the engine unintentionally, it fitted perfect !!






Cylinder rods and oil tubes.


It not only spins but also flies.

If you throw it !! 😀

Intake pipes.


The kit’s ones are to be attached on the left side, but real ones on the right side.


Intake pipes aren’t like the spokes of a wheel but like a spiral.


Something like cover (White parts).


Exhaust pipes.


Vaporizing duct.


The well known only-colored photo of Ki-51 seems to show that the duct was red-orange.(Or, is that red rust ? I’m not sure)


The engine almost completed !


But after almost completed the engine, I faced a ploblem of “Number of Cowling Flaps”…

More than 2,000 Ki-51 was manufactured in WW2, however we can hardly find the sources about it to refer in the market. So I often had to do “archeological method” for building the Ki-51 model.

I had been referring to two guide books. One was Maru’s “Mechanism of Militayi Aircfaft Toryu/Type 99 Assault/Tactical Reconnaissance”, and another one was Arawashi’s “Eagle Eye Series,No.1”.

The both of books describes that Ki-51’s cowling flaps was devided on the center line of the fuselage top. And the bottom’s cowling flap was on the bottom line. This means that Ki-51 had 15 cowling flaps, and as well as the Nichimo’s kit.

But if it is true, the position of the exhaust pipe is different from the drawing from side view. It’s a paradox…

At that time, I unexpectedly found a photo of a Ki-51’s good model, which I took at the “Tachiarai War and Peace Museum” in Fukuoka prefecture. The photo shows that the top’s flap is on the top center line of fuselage.

So, the top is 1. The bottom is 1. The eace side is 6.
1 + 1 + 6 x 2 = 14…
14….14 cylinders…

I could kick myself !!! 😮
Ha-26 engine has 14 cylinders !!! To be general, airplane’s cowling flap has the same number and position as its engine cylinders !!!


Cut apart cowling flap part into peaces, and rebuilt. Pet bottle cap is good for this work !


Painted cowling flaps in Kai-Ryoku-syoku(Grey Green).

“Tachiarai War and Peace museum” is a good place to see valuable materials. During the war, Tachiarai Air Base was the one of the biggest army air base in the world. At the same time, Tachiarai-town is my grandfather’s birth place. When you come to Japan, please visit there !! 😉


Make meter panel thinner, and cut apart.


Punched the holes, and attached junk etching parts from the back side.


Vertical rudder


Interior painting.

Till the middle of WW2, the interior color of IJA planes was regulated as “Kai-ai-syoku”(Dark blue grey).



Levers made of bearing balls and brass wires.

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