Hasegawa 1/32 Ki-100-1b (conversion)
$ around $50 or so
AC0032C Ki.100-Ib conversion set used. Price: 39.95 Pounds (about $64 at
today's exchange rate).
In March 1945, B-29 crews began reporting the appearance
of a previously-unknown type of Japanese Army fighter appearing in squadron
strength at altitude over
The new radial-engined fighter had superb
maneuverability and high altitude performance.
In truth, the “new”
Ki.100-I Army Type 5 Fighter was the most remarkable improvisation to be used by
any combatant in the Second World War.
By 1944, production of the
Ha‑40, the Japanese adaptation of the German Daimler‑Benz DB 601 engine, had all
but failed completely, and many of those engines that were produced did not
achieve their stated performance.
Not only that, but the Ha-140 which was to replace the
Ha-40 had been revealed as a complete failure. This made for a very difficult
situation for the
the fighter that used these engines, the Ki.61 Hien,
was one of the few JAAF fighters capable of meeting the new threat of high
altitude raids over Japan by the B-29, which had entered the war in strength
when missions began to be flown from the Marianas that November.
This was particularly important because the
Ki.61-II-KAI, which had been introduced into production that fall, was an
improved model that would have been more capable of taking on the F6 Hellcat,
F4U Corsair and P-51 Mustang, powered by the new 1,500 hp Kawasaki Ha‑140
Unfortunately, the Ha-140 never lived up to its design specifications,
with the majority of engines produced either being rejected on quality grounds
or failing in use.
Looking around for an engine of equivalent power that
was more dependable, Kawasaki presented the JAAF with a proposal to power these
airframes with a 1,500 hp Mitsubishi Ha‑112‑II Kinsei
60, a 14‑cylinder, two‑row radial engine developed for the Japanese Navy; such
was the crisis, traditional Army-Navy rivalry was forgotten in the decision to
make use of this engine.
The necessary redesign to successfully mate a narrow
fuselage designed for an inline powerplant with a radial engine took most of
November and December 1944.
The desperate need for the re‑engined fighter became
even more urgent on
January 19, 1945,
when a B‑29 raid destroyed the Ha-140 production plant. Some 280 finished
Ki.61-IIs were left without a powerplant.
Kawasaki's chief engineer, Takeo Doi, his assistant
Makato Owada, and Tomio Oguchi, head of engine systems, worked through several
concepts for redesigning the Ki‑61 airframe to accept the new engine.
They relied on
close study of a Fw-190A, which was remarkable for its closely-cowled radial.
They finally settled on a solution which involved a
second skin fairing being riveted to the fuselage to smooth out the airflow
behind the adjustable cooling flaps, and multiple exhaust stubs of the new
In fact, these ejector stubs did add approximately 10-12 mph to
the top speed.
The first of three prototypes, know designated Ki.100-I,
February 1, 1945.
The new engine gave perfect performance, and even
increased the rate of climb and maneuverability of the airframe, though the top
speed - a respectable 380 mph - was not as much as hoped.
Best of all, this performance did not fall off as much
at high altitude as did other Japanese fighters, though there was a demonstrated
need for a superior two-stage supercharger.
Armament was two fuselage‑mounted 20 mm Ho‑5 cannons,
each with 200 rpg, with two wing‑mounted 12.7 mm Ho‑103 machine guns with 250
The emergency measure of adapting the Ki.61‑II‑KAI
fighter to carry a Mitsubishi radial engine had resulted in one of the best
interceptors used by the Army during the entire war.
Of equal importance to its performance, the fighter was
easy to fly, and - like the Ki.84 - could make a good pilot a superior pilot.
Remarkably, the Ki.100-I was quickly issued to the
and missions began in early March 1945, only five weeks after the first
The modification tempo increased such that by late April
1945, nearly all Sentais using the
Ki.61 had been at least partially-equipped with the Ki.100-I, and 271 airframes
had been so modified between March and June, 1945.
In June 1945, the Ki.100-Ib appeared.
This was modified from the Ki.61-III
airframe that entered production in early 1945, and featured a cut-down rear
fuselage, and a 360-degree canopy.
Only 118 of these superior versions were produced before
the Kagamigahara factory was finally destroyed by B-29s in late July, 1945, with
only 15 Ki.100-Ib's delivered that month.
Although there were far fewer Ki.100s available than
Ki.84s, the JAAF saw the airplane as one of the most important fighters in the
In late March and April 1945,
experienced instructors from the
flew the Ki.100 in extensive tests against the Ki.84, considered to be the best
JAAF fighter in operational service. Their conclusions were that, given pilots
of equal experience, the Ki.100 would always win.
The Ki.100 first entered combat on the night of
during the first great
The first loss occurred on
April 7, 1945,
when the Ki.100 flown by Master Sergeant Yasuo Hiema of the
18th Sentai was shot down by a B‑29 after "attacking the
formation again and again".
One of the most astounding demonstrations of the
superiority of the Ki.100-Ib occurred on July 18, 1945, when 12 Ki.100s led
Major Yohei Hinoki, lead instructor of the Akeno f\Fighter School attacked a
flight of the 506th Fighter Group
Hinoki, the “Japanese Douglas Bader,” flew with wooden leg after
a combat with a P-51A flown by future ace Robert Mulhollem over Rangoon in
The 506th FG and the
21st FG had sortied from Iwo Jima
on a long range mission to strafe airfields in the Nagoya region.
Hinoki's fighter had such severe propeller vibration
that during the combat he could not use his gunsight, and shot down Captain
Robert Benbow from a range of less than 100 feet.
The Akeno instructors shot down 4 P-51Ds that day
without loss to themselves.
The well-known 244th
Sentai received 24 of the Ki.100-Ib fighters in
mid-July, after the unit had relocated from the Tokyo metropolitan area to
southern Kyushu in preparation for the coming invasion everyone expected.
On July 25, 1945, 18 Ki.100s of the
ran across ten F6F-5 Hellcats from VF-31, operating from the USS
Belleau Wood off the coast of Kyushu.
In the subsequent air battle, the Japanese claimed 12
victories with only two losses. Claims and counter‑claims regarding the "true"
results have resulted in later years with agreement that the actual losses were
two Hellcats and two Ki.100s, including the Ki.100 flown by Major Tsutae Obara,
which collied with the Hellcat flown by Ensign Edwin White, killing both pilots.
The Hellcat pilots were unanimous in stating this was
the most difficult fight any of them had been in.
The last Ki.100 to be shot down was the Ki.100-Ib flown
by Sergeant Major Fumihiko Tamagake of the 244th
Sentai, which was shot down by a P-51D on August
14, 1945, a day before the surrender of Japan.
Post-war testing revealed that a well‑handled Ki.100-Ib
could out‑maneuver any American fighter including the P‑51D Mustang and the
P‑47N Thunderbolt, and could hold its own with the F8F Bearcat.
For a look at the beautiful Hasegawa Ki. 61, you can
read my review.
From the design of the kit, it was obvious that at some
point Hasegawa would release the Ki.100 series.
However, this has not happened in the past two years,
and so Alley Cat Models has released a pair of beautiful resin conversion kits
to enable a modeler to produce a Ki.100-I or a Ki.100-Ib.
The masters, research, and artwork for the sets have
been done by Phil Edwards.
This set for the Ki.100-Ib provides 20 resin parts and
six clear resin parts, including a complete new fuselage, under fuselage section
with integral wing spar, engine, propeller blades, spinner, chin radiator, rear
cockpit deck parts, 3 part clear cast canopy, new clear wing tip lights,
separate rudder, correct gun bay covers (since not all kits are of the proper
Ki.61-Ib, with machine gun wing armament).
Personal marking decals are provided for Ki.100-Ibs
flown by Major Hiroki of the Akeno Flying School, Major Teruhiko Kobayashi,
commander of the 244th Sentai, and
Major Yasuhida Baba of the 5th
The rest of the decals are taken from the donor kit.
This is a straightforward “drop fit” conversion, and any
modeler with experience of building eastern European limited-run kits should
have no difficulty producing a very nice model.
I began construction by cleaning up the resin parts,
since the kit had quite a bit of flash. I then test-fitted the fuselage parts
and filed and sanded the mating areas as necessary to insure a good fit.
With all that done, I painted the engine and attached it
to one fuselage half.
I then attached the exhaust stubs, and glued the
fuselage halves together.
I finished off by attaching the front
cowling, and the plastic part from the donor kit for the tailwheel assembly.
I filled all the gaps with cyanoacrylate glue, then
followed that with liberal applications of Tamiya's “Mr. Surfacer” plastic
putty. I next assembled the wings and horizontal stabilizers and set everything
aside to set up.
I painted and assembled the kit cockpit per
instructions, adding in an Eduard JAAF photoetch seat belt.
When this was finished, I slid it into position in the
fuselage, and then attached the wing spar and lower fuselage section.
This last required quite a bit of test-fitting and
modification to get a good fit, which was not unexpected and presented no
Before assembling all the subassemblies, I sanded the
fuselage seams smooth, giving them all a second coat of “Mr. Surfacer” and
Since the resin was a bit “rough” to the touch, I sanded down the
entire fuselage assembly with fine-grit Wet ‘r' Dry, then applied Tamiya rubbing
compound and buffed it out with my Dremel. I then rescribed panel lines where
The spinner was assembled and seams filled, then the
prop blades were glued in position.
With careful test-fitting, the wings fitted easily and I
only needed some “Mr. Surfacer” on the upper fuselage-wing seam.
The horizontal stabilizers also went on without
The Ki.100-Ib came in any variation of Japanese Army
Green upper surfaces with unpainted aluminum lower surfaces, and Japanese Army
Grey fabric control surfaces, with yellow wing leading edges, that one cares to
I first painted the yellow area on the wing leading edges and masked it
off, then painted the lower areas of the control surfaces with Tamiya “J.A.
Grey,” and masked them off.
I painted the lower surfaces with Tamiya “Flat
Aluminum,” then applied a light coat of Talon “Aluminum” to give a good metallic
The upper surfaces were painted Tamiya “J.A. Green,” which I lightly
These airplanes were practically new still at the end of the war,
show them in good condition, so not a lot of “fading” was needed, just enough to
not have a totally-monochromatic surface.
The prop and spinner was painted with Tamiya “Flat
I finished off with a couple coasts of Xtracrylix Gloss Varnish.
This is the one area I encountered difficulty.
Had I chosen to do the Akeno Flying School airplane or
the 5th Sentai airplane, I would
have had no problem, since these personal markings all include white, with other
colors printed over that, and the white decal is sufficiently opaque to use on a
dark colored surface, so there are no problems with these markings.
Unfortunately, the yellow stripe and the red of the
Sentai insignia for the 244th
Sentai airplane are not sufficiently opaque.
I was able to substitute a Sentai insignia from a
Lifelike Decals sheet, and a yellow stripe from the decal dungeon.
Alley Cat has told me that the next batch of decals will
be printed with sufficient opacity to solve this problem.
I also had to use Solvaset to get the kit decals to
settle down in the panel lines.
I gave the model two coats of Xtracrylix Flat Varnish on
the painted surfaces, leaving the aluminum surface alone other than to varnish
the insignias and the flying surfaces.
Since these airplanes were not “dinged” I only applied
exhaust staining and gunfire staining, to create a model of the airplane as it
might have appeared after the combat with VF-31 on July 25, 1945.
I then unmasked the canopy and attached the sliding
section in the open position.
The Alley Cat canopy is designed to be used only in the
closed position, so I substituted the kit canopy part that can be posed open.
I attached the landing gear and prop, and all was
It's likely that Hasegawa will eventually do the Ki.100
series, given the design of the Ki.61 kit and the company's history of
“maximizing value” of the molds.
When this might happen is anyone's guess, but I would
bet on it not happening soon, given their recent history.
For modelers who want to have a Ki.100 in their
collection, these conversion kits by Alley Cat are excellent value, and are not
at all hard to use by a modeler with any successful experience of limited-run
This Ki.100 looks great sitting next to my Ki.61-Ib and Ki.61-Ic models.
Review kit courtesy
of my wallet.
Alley Cat Conversion set courtesy of Alley Cat Productions.
Get yours at
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