This section has been compiled from various intelligence reports submitted by U.S. observers
during the operations on Attu Island. A preliminary report on the Attu operations was published
in Intelligence Bulletin, Volume I, No. 11. Except for isolated instances, none
of the information in the preliminary report is repeated below.
2. INDIVIDUAL CHARACTERISTICS
With few exceptions, the individual Japanese soldier on Attu lived up to all our expectations. He
was tough, active, tricky, and treacherous, but absolutely no "superman." He was subject to
fear, to confusion, and to thoughtless acts of desperation. As a rule, however, he could be
counted on to fight to the last....
Regarding the characteristics of the individual Japanese soldier, a U.S. platoon
I feel very definitely that if a continual advance is made on the Jap, he becomes
confused and doesn't quite know what to do next. One thing is certain. This business
about his being a superman is so much tripe. When you start giving him the real
business, he will run like hell and be twice as scared as you are—and when I
think how scared I was, that's saying a lot.
3. DEFENSIVE POSITIONS
As a rule, the Japanese on Attu organized their defensive positions on high ground
which ordinarily (1) afforded plunging fire on the flanks and rear of forces pushing
inland from the coast, (2) was extremely to moderately hard to reach, (3) was
largely secure from our naval fire and aerial strafing, and (4) was extremely hard
to observe from the valley lowlands.
The enemy apparently organized the terrain so that they could obtain the best possible
performance from each rifle and automatic weapon. Positions frequently were located
high in side gullies. Trenches or tunnels (sometimes both) usually connected
foxholes, rifle bays, and automatic-weapon positions, so that a single rifleman or
automatic weapon man might have several fields of fire and several positions. These
enabled the Japanese to take up a new position when, or before, an occupied position
became untenable. Such shifting about tended to deceive our troops with respect to
the enemy's strength.
The foxholes, trenches, and bays commanding the flanks and rear of inward-pushing forces
were far more numerous than the positions set up for frontal defense. Trenches, of the
zigzag type, usually were about 75 yards long, 3 feet wide, and 4 to 5 feet
Broadly speaking, the Japanese did not organize a series of strong points, as we conceive
it, but organized the terrain into scattered and frequently isolated strong points which
were very loosely tied together with supporting fires. In selecting these strong points, the
enemy apparently paid little attention to routes for withdrawals. This was particularly
true in the case of machine-gun positions.
Sometimes holes which, at a distance, appeared to be foxholes turned out to be entrances
to large dugouts, living quarters, caches for supplies, or tunnels to observation
posts or machine-gun positions. In several instances, trenches covered overhead with
timber, dirt, and other forms of camouflage were constructed so as to connect buildings
with gun emplacements.
In many cases small prepared positions for riflemen and machine gunners were found near
large rocks, under the walls of cliffs, and in other naturally protected areas.
b. Machine Guns
As a rule, the Japanese emplacement of machine guns was good with respect to mutual
support. The guns were seldom placed alone. Each was supported by at least one other
gun, generally located from 200 to 500 yards away. This made their reduction more
difficult as all the weapons had to be taken at once—otherwise, the first gun
position taken would receive prompt support from other positions. In at least one
instance, this support was strengthened by the addition of a rapid-fire cannon, which
twice forced our troops to withdraw under fire after they had taken a machine-gun
position. Also, grenade dischargers were frequently located near machine guns.
Often machine-gun positions were constructed either of blocks of tundra—which
offered good concealment but poor protection—or of small and medium-sized rocks
piled upon each other. Such positions along the rocky ridge tops afforded good camouflage
but, once discovered, were deadly to the occupants because of rock fragments. Several
Japanese bodies in these positions showed evidence that flying pieces of rock had
c. Sniper and Observation Posts
Sniper and observation posts were well located with respect to the terrain. They had
no paths leading to them, and were well camouflaged with grass and, in some instances, turf
and moss. A few of these posts had a T-shaped stick, about 3 feet
high, which apparently was used as a rest for field glasses. The Japanese sniper or
sentry apparently approached his post from a different direction each time he
reported. Relief parties did not come close to the post.
4. DEFENSIVE TACTICS
By siting their weapons on high ground, the Japanese secured maximum fields of fire
and excellent opportunities for long-range fire. They utilized both advantages. Most
of their fire came at us from ranges of 1,000 yards or more. Some of the enemy's
heavy machine guns were equipped with telescopic sights for long ranges, up
to 2,500 yards.
This long-distance fire, delivered from high, well-concealed positions, was plunging
steeply when it reached our troops, and frequently pinned them down. Except for its
harassing value, this fire was not considered effective. The enemy's rifles and machine
guns had no grazing fire at such long ranges, and the cones of fire were too
dispersed to be effective against individuals. Also, the opening of fire at such
long ranges gave our forces a pretty good idea as to the location of the Japanese positions.
b. Machine Guns
In addition to siting their machine guns well, the Japanese also had prepared elaborate
range cards for firing. Apparently many of the guns had been registered carefully on
terrain features before our troops went ashore, and had been laid on specific ground
areas with planned patterns of mutually supporting cross fire. In many cases the enemy
guns on ridges were set to search out every hollow in certain valley areas. Small range
and deflection stakes were often found in front of enemy positions. This arrangement
permitted the Japanese to open well-aimed fire, regardless of visibility.
As our troops advanced close to the Japanese positions, the hostile fire frequently
was high—probably because many of the enemy gunners forgot to change their
c. Use of Bayonets
Despite the fact that the Japanese place considerable emphasis on the use of cold steel in
training, on Attu the enemy gave a poor performance with the bayonet, as a rule. Some
observers believed the enemy may have feared our generally larger stature and,
presumably, greater physical strength.
The Japanese placed great emphasis on the disruption of our communication facilities. Our
soldiers could traverse wide areas known to be infested by enemy snipers, without being
fired upon. However, when a soldier stopped for the apparent purpose of repairing
telephone wire, snipers' bullets would begin to whine all around him. In the final
all-out enemy attack, bayonets severed our wires in certain areas at an average
interval of 20 feet, and rearward communications were disrupted. In some cases, enemy
bayonets scratched the insulation off our wires in order to ground the circuits.
Japanese camouflage on Attu was excellent. The enemy relied mainly on natural material, such
as grass, moss, and limbs of dwarf pussy willow trees. Other materials included the
usual camouflage nets for the body and head, camouflage capes, strips of rice-straw matting
and grass matting, rope matting, dummy men and guns, and white snow parkas (some observers
reported that white wrap-around snow pants also were used).
b. Natural Material
Individual hillside positions for Japanese soldiers were usually shielded by pussy willow
branches. These were draped with moss and tufts of grass which almost completely
hid the opening.
Tufts of grass were used to mask the narrow slits (for observation and firing) of
covered positions. The outlines and shadows of these positions were broken up by
tufts of grass which were loosely twisted into ropes. Sometimes rice straw was used
in making the ropes. Straw matting also was used, to cover openings or excavations.
All of these types of camouflage were generally used on one-man structures, while the
principles of limiting shadows and of reducing silhouette elevation to a minimum were
also generally well utilized.
Rope 1/2 inch in diameter was found in large quantities. In utilizing it for camouflage, the
Japanese opened the rope strands—as in splicing—placed tufts of compressed
grass between the strands, fluffed them out, and then twisted the strands of rope back into
place. The tufts of grass were 15 to 18 inches long and 1 inch in diameter.
After camouflaging a rope in the above manner, the Japanese coiled it up, or put it into
immediate use by tossing a coil over the object to be camouflaged. This and other coils
were then crisscrossed and secured until the camouflage operation had been completed.
d. Wearing Apparel
The individual camouflage nets were made of vari-colored netting. Wisps of similarly dyed
raffia (strong fibrous strands from the leaf stalks of raffia palm trees) were tied into
the string meshes of each section.
Individual nets frequently were laced together to cover conical tents. In many instances
high revetments were built around the tents, and the camouflage nets fell at a gentle
angle from the peak of the tent to the revetment wall. The practice of locating tents at
the bottom of deep and almost inaccessible ravines provided an additional safeguard.
The white snow parkas were used for wearing above the snow line. Where possible, the
enemy avoided travel across snow patches during the day unless clad in white
clothing. When the enemy soldiers moved across the pale grass of the hillsides
they often moved in a crouching position with strips of grass matting held in
front of them.
Individual enemy riflemen and observers were supplied with hooded camouflage capes, which
were made of light, rain-repellant tan paper. The capes were about 9 by 6 feet, and
were tied with tie strings. Behind and under these capes, riflemen and observers
could sit for a day at a time, dry and protected from wind and rain and indistinguishable
from the tundra.
As a rule, the Japanese constructed cooking and storage chambers, latrines, and bath
houses by cutting into the sides of hills or banks. They made these structures
blend with the surrounding terrain by grass covers, grass or straw, willow
branches, and sometimes turf.
Office buildings, barracks, officers' quarters, radio installations, and hospitals in the
more developed centers were generally constructed with only the roof extending
above ground level (barabara type). The roofs had low peaks, casting only small
shadows. The tops of these roofs were covered with sod, which formed a green
carpet over each gable. The sod also helped to shed the rain, and gave limited
protection from fragments of shells bursting nearby. Glass windows inserted near
the gables as skylights were covered on top with loosely strewn grass to prevent
daytime detection, while blackout curtains covered the windows at night.
The Japanese went some distance from the building to dig up sod for covering the
roofs. The denuded areas left after the sod was removed were rectangular. It is
believed that the enemy prepared the areas in this manner with the belief that
the contrasting color would befuddle our air observers.
Similar deceptive techniques were used in outlining entire trench systems, where
only the surface sod was removed to reveal the dark earth.
Foxholes and machine-gun nests dug in snow-covered ground were covered with white
cloths which blended perfectly with the snow.
Frequently small mounds of dirt were built in front of foxholes and covered with
tundra. This made it impossible to see the foxholes from a lower elevation.
f. Dummy Emplacements
Islands at the entrance to Chicagof harbor contained complete dummy emplacements, including
wooden guns and straw men (made by stuffing salvage uniforms with dry grass).
6. DEVELOPMENTS IN WEAPONS
Several Japanese "barrage" mortars, a comparatively new weapon, were captured on
Attu. The mortar previously had been reported in the South Pacific theater. It was
also noted on Attu that the enemy has made slight changes in hand grenades and
the Model 89 grenade discharger.
a. "Barrage" Mortar
(1) Description.—The "barrage" mortar (see fig. 6) is a simply
designed weapon for area bombardment. It consists of a smooth-bore tube,
approximately 70-mm in diameter and 4 feet long; a base
plate, a rectangular wooden block, and an iron rod, which holds the mortar
in an upright position and controls the angle of elevation for firing. The
wooden block, 12 inches long, 10 inches wide, and 8 inches thick, is used to
absorb the shock during firing and to prevent the base plate from digging
into the ground. The base plate is fastened to the block by two bolts. The
iron rod, about 1 inch in diameter and 18 inches long, is fastened to
the bottom of the block and extends straight down.
The elevation or depression of the mortar is determined solely by the angle at
which the rod is stuck into the ground. The weapon apparently has no
The tube of the mortar screws onto the base plate, which has a threaded male
fitting. The firing pin protrudes upward from the center of this base fitting.
Figure 6.—Japanese "Barrage" Mortar.
The shell used in the mortar has an over-all length of 10 3/4 inches and a
diameter of 2 3/4 inches (see fig. 7). It is made of steel, is
cylindrical in shape, and is painted black. The nose of the shell is capped
by a rounded wooden disk on a metal base, and is secured to the casing by
six rivets. A red band is painted around the shell just below a wooden cap.
The shell is divided into three main sections, namely:
(a) Base section, which houses a central percussion cap and explosive
charges (in silk bags) for propelling the shell from the mortar;
(b) Central section, which houses powder delay trains and secondary charges
of black powder for expelling seven bomb containers; and
Figure 7.—Shell for
Japanese "Barrage" Mortar. (Part a shows the details of the bomb;
part b illustrates the three phases of action which occur in the air
after the mortar is fired; and c is a view of the shell as a whole.)
(c) Top section, which carries a silk parachute 12 inches in diameter and the seven
bomb containers. (The parachute is fastened to a 6-foot-long cord, the other
end of which is secured to the inside bottom of the casing.)
Each of the bomb containers, which are made of steel, has a 4 1/2-inch square
silk parachute fitted neatly into it. Also housed in each container is a steel
tube bomb 3 1/4 inches long and 11/16 inch in diameter. The tube is filled
with explosive, and is covered at the open end by a screw cap, which has a hole
in its center for the passage of a cord fitted with a phosphorus igniter. The
cord is 6 feet long. Its free end is attached to a rice-paper parachute
which is 15 inches in diameter.
The seven bombs are marked similar to the mortar shell—they are painted
black except for a red band below the screw cap. The bombs also bear the Japanese
inscription "Dangerous—don't touch."
(2) Operation.—When the shell is dropped into the mortar tube, its
primer falls against the firing pin and activates the propelling charge. In
addition to shooting the shell from the tube, the explosion of the propelling
charge also fires a delay powder train.
This delay train burns momentarily until it reaches powder charges, the explosion
of which expels, in mid-air, the seven bomb containers and the silk parachute
housed in the top section. This parachute apparently is designed to check the
speed of the shell and throw it violently off its course, so that the bomb
containers, with their small silk parachutes, may be scattered without
The explosion of the charges that expel the bomb containers also activates powder
delay trains in each of the bomb containers. These burning delay trains then
explode expelling charges in the base of each container and force the bombs, each
with its rice-paper parachute, from their containers. In the case of each bomb, the
jerk caused by the opening of its parachute activates the phosphorus igniter
which, in turn, causes the bomb to detonate.
Figure 7b illustrates three phases which are involved in the firing of this
mortar shell. Summing up, it will be noted that, after activation of the
expelling charges in the bomb containers, there are—at least
momentarily—15 different elements air-borne by parachutes, namely: the
shell casing, the seven bomb containers, and the seven bombs.
(3) Purpose.—The explosive content in the bombs is believed capable of
producing a heavy detonation which would shatter the light casing into small
fragments—too small to have any antipersonnel effect unless the bombs
detonated close to personnel.
The warning inscribed on the bomb suggests that it may also be designed for use as a
booby trap. In this case, the blast effect would be highly dangerous.
If necessary to handle an unexploded bomb, the following safety precautions should
(a) Do not lift the bomb without lifting the parachute at the same time, or vice versa.
(b) Unscrew the cap only when the cord is slack.
(c) Dispose of the phosphorus match composition by placing it in water or by
burning it after separation from the bomb.
b. Hand Grenades
The hand grenades inspected on Attu have an additional safety feature. The new
safety is a small, loosely set screw which fits into the fuze at the top—underneath
the cap. To arm the grenades found on Attu, it was necessary to turn the screw
Strewn about most of the captured Japanese positions were a number of hand grenades
with their pins pulled out. Since the pins have to be withdrawn and the grenade
hit sharply on a hard object before it will explode, the enemy may have removed
the pins in order to have the weapons in a better state of readiness. Also, the pins
may have been removed so that the grenades could serve as booby traps. In this
case, the Japanese probably hoped that unwary U.S. soldiers would stumble onto
the grenades, and accidentally kick the fuzes with enough force to cause
detonation of the weapons.
c. Grenade Dischargers
The Model 89 grenade dischargers examined on Attu had a small bubble leveling device
attached to the right side of the breech. The device indicates the angle at
which the discharger is held, and thus enables the operator, or operators, to
maintain a constant angle of fire.
The projectile used in this grenade penetrates fairly deep into soft ground before
the fuze, which has a slight delay element, is activated. This delay considerably
restricted the effective bursting area of the shell.
7. NOTES ON EQUIPMENT
a. For the Individual Soldier
(1) Packs.—Apparently the Japanese use their standard pack in all
climates. It is only slightly larger than the U.S. canvas field bag, and will
probably hold only rations, a change of socks, and perhaps a change of
underwear. However, the pack is designed so that other articles may be
strapped on. Several packs found ready for carrying had a blanket and
wool overcoat in separate horseshoe-shape rolls, an extra pair of shoes, a
shelter half, poles and pins, and felt leggings. As a whole it was a fairly
(2) Shelter Half.—The Japanese shelter half is a light-weight tarpaulin
about 4 1/2 feet square. It is sometimes pitched like our own, with another
to form a pup tent. The halves have no buttons; they are laced together. The pup
tent is open at both ends. A segmented, or foldable, pole is supplied with each
shelter half. Usually Japanese soldiers simply cover themselves in a foxhole
with their own shelter half.
(3) Cartridge Pouch.—The Japanese cartridge pouch is made of laminated
duck, which has been thoroughly impregnated with rubber to give it a certain amount of
rigidity and yet allow for resilience. The arrangement used to effect a snap
closure is simply a buttonhole over a collar-button type steel fastener. The pouch
has a partition in the inside to allow for separation of ammunition clips. Loops
permit the pouch to hang from the waist belt.
(4) Entrenching Shovel.—The Japanese entrenching shovel has a
sturdier handle and a more pointed blade than ours, and it was better for
cutting the matted grass roots in the Attu tundra.
(5) Skis.—These were called "Glacier skis." They were short and
broad, with about two-thirds of the length extending in front of the toes. This
permitted excellent maneuverability and provided ample flotation on the
granular-type snow found in the Western Aleutians.
(6) First-Aid Packet.—All Japanese soldiers are taught first aid, and
all carry a first-aid packet somewhat similar to the U.S. packet. The enemy has a
powder which is designed to serve about the same purposes as our sulfa drugs, and
another powder, which the solder takes internally when wounded.
b. Wearing Apparel
(1) Headgear.—Enemy troops on Attu were equipped with a steel
helmet, which was painted olive drab and bore the Japanese Army star
insignia in the front center. The helmet, somewhat smaller than ours, apparently
was made of unalloyed, or poorly alloyed, steel, and it was not as tough or
as resistant to shock as the U.S. helmet.
The typical peaked Japanese field cap was found in large quantities. Also found
were large numbers of a winter cap, which had ear flaps, and a fold-down section
to cover the head, helmet-wise, and also the lower part of the face. The cap was
lined with real fur or manufactured fleece.
Also found were grayish purple knitted helmets, made of wool and silk, which
could be worn under the steel helmet.
(2) Uniforms.—Japanese officers wore clothing scarcely different
from that of the enlisted man. The material for officers' uniforms was
superior in some cases, but the tailoring was the same.