The Japanese Zero Fighter

Intelligence report on a Japanese Zero fighter forced down over the Aleutian Islands and captured by American forces. Source: Bureau of Naval Personnel Information Bulletin, (“All Hands Magazine”), November 1942.

Japanese Zero Fighter
Though it now wears American colors, the airplane above is a vaunted Japanese Zero warplane (Mitsubishi ’00), disabled and forced down during an air battle over the Aleutian Islands. Salvaged by Americans and shipped to San Diego for repair and testing, the highly maneuverable fighter has a wing span of 39 feet 5 inches and an over-all length of 30 feet 3 inches. It mounts two 22-mm. low velocity cannon in the wings and two 7.7 guns in the nose.

The Japanese “Zero” Fighter
Plane proves maneuverable but protection is poor

A Japanese Zero fighter (Mitsubishi ’00), which was salvaged after being only slightly damaged when forced down in the Aleutian Islands, has been brought to the United States and repaired at the Naval Air Station, San Diego, Calif.

The enemy plane will be brought to the Naval Air Station at Anacostia, D.C., where Navy pilots will put it through exhaustive tests in order to obtain data on its performance characteristics. Preliminary tests already have taken place at San Diego.

Present plans call for the Zero to be flown across the United States, in view of the difficulties attached to shipping it. Because the Zero’s airframe is a single unit and the wings are riveted solidly to the fuselage, it is not considered feasible to attempt disassembly of the plane. Details of the proposed cross-country flight have not been worked out.

When salvaged, the Zero was painted a smooth light grey tinted with blue and light green, a coloring selected for operations in the foggy Aleutian area. It has been repainted in Navy colors.

Preliminary flight tests of the Zero developed a top speed of slightly less than 300 m.p.h. Later tests may increase this speed somewhat.

The Zero shows to best advantage in a dogfight where tight turns make high speeds impossible. Then its maneuverability and climbing speed come into play.

Around 200 m.p.h. the Zero is very light on the controls, but at higher speeds the controls become stiff. Above 225 m.p.h. the Zero will not make a fast roll because of this stiffness. At 380 m.p.h., in a dive, the Zero develops marked flutter and vibration, which may be inherent or due to some undetected disalignment caused by its rough landing in the Aleutians.

Otherwise the Zero is a stable, easy-to-fly plane with generally good flying characteristics. Its lightness is not gained by flimsy construction, as it is well designed. The lack of self-sealing tanks and armor protection for the pilot, which mainly accounts for its lightness, have made its over-all combat record against the Navy’s Grumman Wildcat a poor one. The Zero’s empty weight is 3,781 pounds and its combat weight, without belly tank, is approximately 5,200 pounds.

The 900-horsepower radial engine is a 14-cylinder, double-row design using modifications or direct adoption of many features found in our Pratt & Whitney and Wright engines. The propeller is a three-bladed, constant speed, hydraulic type identical with the Hamilton model. Radio equipment is copied after Fairchild units.

The over-all length of the Zero is 30’3″, its wing span 39’5″. The wings are hinged 2 feet from the tips to allow folding for easier carrier handling. The cockpit would be uncomfortably small for most of our pilots.

Armament consists of two 22-mm. low velocity cannon, one mounted in each wing, with 60 rounds of ammunition, and two 7.7 guns, with 500 rounds each, in the nose to fire through the propeller disk.


Submersible Baka

“Submersible Baka” from C.I.C. (Combat Information Center), U.S. Office of the Chief of Naval Operations, Vol. II, No. 7, July 1945.


Some midget subs are to the Japanese I and RO class sub what BAKA is to the Betty 22. The parent sub gives her hitchhiker the necessary cruising range, while the midget’s own torpedo load has deadly striking power for far reaching effects. Other midgets are carried cargo fashion on specially fitted seaplane tenders and Japanese capital ships. Midget subs are standard in size. A captured midget sub manual indicates three types–the KO, OTSU, and HEI. The KO type is thought to be standard. 82 feet in length and with a 6 foot beam this type can make 22 knots for a short period (about ten minutes). For normal operations speeds of 6 to 9 knots are probable. The HEI is 82 feet long, 6 feet wide with speeds up to 16 knots and an operating radius of 60 to 80 miles (submerged in the daytime, surfaced at night). The midgets can and do operate without the hitch-hiking feature having a cruising range of 120 to 180 miles on their own without battery recharge from an outside source. This limits them to a 60 mile cruising radius unless a suicide venture is prescribed. Coastal indentations near areas of obvious future operations provide concealment for midget bases. When they go pick-a-back on larger subs, attacks are possible at any distance.


Tojo Fighter


The information contained in this summary should be transferred immediately to Informational Intelligence Summary No. 43-26, “Japanese Aircraft and Armament,” revised September 1943.

New Japanese Type 2 Single-Engine Fighter, TOJO


1. Informational Intelligence Summaries No. 43-49 of 10 November and No. 43-51 of 30 November contained certain previously known details of the Type 2 single-engine fighter TOJO. A recent report has been received that includes sketches and drawings of this aircraft, these being reproduced in Fig. 6. Data supplementary to that given in the Summaries mentioned above follows:

a. Wing is constructed in six sections. It is joined by bolted-type joints at the centerline, and at points 6 1/2 ft., and 12 ft. 11 in. outboard from the centerline, the last-named being the tip attachment. Each wing, therefore, is composed of sections 6 1/2 ft., 6 ft. 5 in. and 2 ft. 8 in. long. No protective or de-icing devices are on or in wing leading edge.

Nakajima Ki-44 Shoki Tojo Fighter

Figure 6: Tojo

b. Fowler type flaps are operated hydraulically as well as the engine cowl flaps. A hand hydraulic pump is incorporated in the system as well as the engine-driven pump.

c. Cockpit is high-set over wing, with little streamlining.

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Tactical and Technical Trends #34

The U.S. intelligence articles from Tactical and Technical Trends, No. 34, September 1943 have been added to the main Lone Sentry website:

The Me-410 Aircraft  ◊  Protection Against Japanese Aerial Bombing  ◊  General von Arnim’s Orders for Ground Deployment  ◊  Italian L Type Grenade  ◊  German Conversion of French 75s into Antitank Guns  ◊  Japanese 70-mm Howitzer Model 92  ◊  Notes on German Artillery Tactics in Tunisia  ◊  Russian Artillery Support in Tank Attacks  ◊  Notes of a British Armored Force Officer on German Tank Employment  ◊  Detailed Report on the German “Tiger” PzKw 6  ◊  Italian Portable Flame Thrower, Model 41  ◊  German Compass Card  ◊  German Butterfly Bomb  ◊  Notes on the German Infantry Division  ◊  Notes on Mobile Surgical Units in the Middle East  ◊  Axis Use of Skoda AA/AT Gun  ◊  Testing Antiaircraft Gun Barrels in Combat Areas  ◊  Japanese 12.7-mm (Fixed Mount) Aircraft Machine Gun  ◊  German Recognition Signals  ◊  Drinking Water from the Rattan Vine  ◊  Lessons from the New Zealand Division Operations in Cyrenaica



When the Allied forces first encountered the Tiger II in Normandy in the summer of 1944, the panzer was briefly referred to as the “Pantiger”. The Associated Press picked up the name “Pantiger” in their article on August 19th:

Germans have thrown a huge new, heavily armored tank into action on both the Russian and northern French fronts in an effort to stem the Allied advances, but first reports denied it was a “super weapon.”

One of the new monsters weighing over 65 tons and with six inch armor plate—an inch and a half thicker than anything the enemy yet has put into action—was taken by the British on the Orne river front. The tank was a victim of a mechanical breakdown and never had fired a shot in battle.

Christened the “Pantiger” by its captors, the tank combines the best features of the Nazi Tiger and Panther tanks, which weigh 45 tons each. It is 23 feet long and over 11 feet wide, has an extra wheel on each side of its tracks and a huge, clumsy looking turret.

The name “Pantiger” was still being used as late as the publication of Tactical and Technical Trends, October 1944.


A new 67-ton German heavy tank—referred to variously as Pantiger and Tiger II—has been employed against the Allies this summer in France. Actually a redesigned Tiger (Pz. Kpfw. VI), it mounts the 8.8-cm Kw. K. 43 gun. On the basis of a preliminary report, the general appearance of the new tank is that of a scaled-up Pz. Kpfw. V (Panther) on the wide Tiger tracks. It conforms to normal German tank practice insofar as the design, lay-out, welding, and interlocking of the main plates are concerned. All sides are sloping. The gun is larger than the Panther gun, and longer than the ordinary Tiger gun. Armor is also thicker than that on either the Panther or the Tiger. The turret is of new design, with bent side plates. In all respects the new tank is larger than the standard Tiger.



German Machine Gun Trick

The following intelligence report on an unusual German remote-controlled machine-gun position encountered by U.S. troops in Normandy was published in the Intelligence Bulletin, Vol. III, No. 4, December 1944.


A U.S. staff sergeant, who served as an observer for a mortar section in the Normandy campaign, reports an unusual German method of firing a machine gun by remote control. Although this method has not been reported by other U.S. soldiers, and although no concrete evidence as to its effectiveness can be presented, the idea is noted here for what it may be worth as a sample of the German soldier’s ingenuity.

German WW2 Remote-Controlled Machine-Gun Trick

German Machine-gun Trick. A close-up of the machine gun, with, its pulleys. Riflemen-observers whistle signals to the gunner, to indicate Allied approach via point A. The gunner zeroes knot A, which trains the muzzle on point A. The cord arrangement for firing is not shown here.

The sergeant tells of inspecting a captured German machine-gun emplacement, which had been prepared in the highly novel manner illustrated in the figure. A rope had been attached to the butt end of the gun. This rope ran through pulleys set up on each side of the rear of the gun, so that movement of the rope would aim the gun in any lateral direction. The gun then was zeroed at certain positions in the field of fire, and these positions were marked by knots in the rope. Thus the gunner could aim the gun, and, by moving the rope back and forth, spray an area with bullets from a position out of the line of fire when the gun was attacked. The gun was fired by a trigger-and-cord arrangement not shown in the original field sketches.

The German machine-gun crew consisted of a gunner and two or three riflemen who served as observers and who reported to the gunner the particular point on the which the gun should be trained.

This machine-gun position appears impractical at best, and may be an incorrect report. The Germans however did produce a special periscopic aiming and firing apparatus for the MG34 and MG42 machine guns. U.S. ordnance reported on this device as the “Deckungszielgerät für le. 34 u. 42 Dezetgerät: Undercover Aiming and Firing Apparatus.”
Deckungszielgerät für le. 34 u. 42 Dezetgerät: WWII Undercover Aiming and Firing Apparatus for MG34 and MG42

Tiger Armor Thickness

These Tiger I and Tiger II armor thickness diagrams were included in a confidential SHAEF intelligence publication on German tanks in October 1944:

PzKpfw “Tiger” – Model E Armour Arrangement
Pzkpfw Tiger I Armor Thickness and Arrangement - Panzer VI (Sdkfz 181)

PzKpfw “Tiger” – Model B Armour Thickness
Pzkpfw VI King Tiger II Armor Thickness

Japanese Suicide Boats

The following U.S. intelligence reports on Japanese suicide boats were published in Enemy on Luzon: An Intelligence Summary:


Japanese suicide crash boats manned by Naval personnel were found in a tunnel on Corregidor. The boats were loaded on small carts which were mounted on rails running from the tunnel to the beach where they were to be launched.

The Navy Suicide Crash Boat was 16 feet 8 inches long and had a beam of 5 feet 8 inches. The hull was plywood construction throughout and was powered by an automotive type, 6-cylinder, in-line, gasoline engine. The explosive charge was built into the hull of the boat. This last feature was the main difference between the Army and Navy suicide boats.

The Type 98 explosive charge weighed 640 pounds and was located below the deck forward of the cockpit. The charge could be fired by three methods: 1) electrically on impact; 2) electrically by closing a switch; and 3) by use of a pull igniter.

From the disposal point of view, the boat was dangerous to anyone unfamiliar with the circuit and switch details. It would also have been simple to rig this boat as a booby trap either electrically or through the pull igniter.

The boat carried a big charge that would be effective against ships. The only defense that a ship had was, as in the case of the suicide plane, accurate gunfire.


Japanese suicide boats, to be manned by Army personnel, were recovered at Lingayen Gulf, Luzon. These craft were the principal weapon of the Japanese Gyoro (“fishing”) battalions.

The army suicide boat was made of plywood with a length of 18½ feet and a beam of 5 feet 10 inches. It was decked with a forward hatch leading to the engine and has a cockpit aft. The boat was powered with a 6-cylinder Chevrolet automotive engine, about 85 horsepower. The maximum speed of the craft was estimated at 35 knots. The fuel capacity was about 56 gallons.

The two 120 kg depth charges were mounted on racks abreast of the cockpit. The charges could be either dropped close aboard or released when the boat crashed into the ship. At least one attack of the former type was made, resulting in damage to a merchant ship during the Luzon campaign.

Although parts of the release mechanism were not available, the operation is believed to have been as follows: the charges were fitted in the racks and held by an arrangement of slings and bars. Rods fitted to extend beyond the bow would be driven back releasing the charges during a collision with another ship. However, the coxwain could place a crossbar forward to release the charges.


Tactical and Technical Trends #12

The U.S. military intelligence articles from Tactical and Technical Trends, No. 12, November 1942 have been added to the main website:

German Aircraft Cannons  ◊  The German Rescue Buoy  ◊  Antiaircraft Defense of Motor Columns on the March  ◊  Japanese Antiaircraft Guns  ◊  Italian 90-mm Multipurpose Gun  ◊  Soviet Antitank Defense  ◊  Armor Penetration of German Antitank Guns  ◊  German Schwere Wurfgerät 40  ◊  German 105-mm Gun  ◊  305-mm Skoda Coast Defense Gun  ◊  210-mm German and Italian Howitzers  ◊  German Self-Propelled 150-mm Howitzer  ◊  Japanese Incendiary Bombs  ◊  Nitrogen Mustard Gases  ◊  Demolition Charge for 20-mm AA/AT Gun  ◊  Winter Fighting in Russia  ◊  German Tactics in the Final Phases at Kharkov  ◊  Crew and Communications of German Mark IV Tank  ◊  Security Measures of a German Armored Division  ◊  Enemy Practices Used in Interrogating Prisoners of War  ◊  Italian Measures for Concealing a Withdrawal  ◊  Operations of the German Tank Recovery Platoon  ◊  Propeller-Driven Sleds  ◊  Report of Italian Pilot on “Crows Feet”  ◊  Markings on German Motor-Maintenance Vehicles  ◊  German Methods Against Russian Winter Conditions  ◊  Katakana (Phonetic Japanese) Used in Communications


How Radio-Controlled Bombs Were Jammed

The following article was printed in the December 1945 issue of C.I.C. (Combat Information Center) published by the U.S. Office of the Chief of Naval Operations.

How Radio-Controlled Bombs Were Jammed

The long, violent history of this war saw the rise of many new or radically improved weapons, from the magnetic mine in the early days to the “personnel-controlled bomb” (suicide plane) of recent fame. The story of Allied countermeasures to the threat of Axis weapons is in many cases as dramatic as the weapons themselves.

Henschel Hs 293 Missile

German planes carried the radio-guided missiles under their wings.

For instance, take the case of the German radio-controlled bomb. As early as 1941 British Intelligence began receiving reports that the Germans were developing a bomb which could be remotely controlled from a parent aircraft. Development and operational use, however, are two different things, and it was not until August, 1943, that the Luftwaffe was ready to unveil it. A group of corvettes on anti-submarine patrol in the Bay of Biscay were attacked by what was identified as a remotely controlled bomb—a missile resembling a small fighter plane—capable of radical maneuvering both in azimuth and elevation. The parent aircraft were DO217 twin-engined bombers. One of the corvettes was sunk, another damaged. Later in August further highly successful attacks were made against shipping in the Mediterranean and Bay of Biscay. The bomb (designated HS293) was released by the parent plane at altitudes of 3000-5000 feet and ranges of three to five miles from the target. The missile was jet-assisted shortly after its release; its speed, variously estimated at the time, is now known to have been about 325 knots. The controlling operator in the plane was able to follow the bomb visually by observing a light in the tail.

During and immediately following the Salerno landings the German guided missile program moved into high gear. The enemy introduced another type of controlled missile, the FX, a radio-corrected 4400 pound bomb of tremendous power and accuracy, as anyone present in Salerno Gulf at that time will testify. The Luftwaffe caught units of the Italian Fleet racing to reach Allied ports and scored heavily with both HS293 and FX bombs. They attacked Allied shipping in Salerno Gulf, sinking and damaging several British and United States warships, large and small. It was estimated that nearly 50% of the bombs launched were hits or damaging near misses.

At that time radio control was suspected (on the basis of prisoner-of-war reports) but was by no means confirmed. The control hand was supposed to lie in the 20 Mc region, and desperate, hastily improvised jamming effort was concentrated in this band, which seemed to improve morale without affecting the accuracy of the missiles.

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