Italian Explosive Ordnance - Bombs (Part 5)

Italian Explosive Ordnance

160kg (CS) Anti-Submarine Bomb

Overall length: 69.8 inches
Body length: 36.2 inches
Body diameter: 13.3 inches
Wall thickness: 0.31 inch
Tail length: 27.2 inches
Tail width: 15.3 inches

Type of filling: TNT
Weight of filling: 99 kilograms

Total weight: 176 kilograms

Fuzing:
-Nose: Type B
-Tail: "Grand-daddy"

  

Color and markings: Overall gray; red nose

Description:  This bomb has a hemispherical nose.  The vanes are short, with a corrugated metal reinforcing ring around the rear of vanes.

 

160kg H.E. Bomb

Overall length: 62.4 inches
Body length: 50.4 inches
Body diameter: 12.6 inches
Tail length: 27.6 inches
Tail width: 12.6 inches

Type of filling: TNT

Weight of filling: Unknown
Total weight: 163.5 kilograms

Fuzing: Nose - Unknown
   

Color and markings: Overall gray; red nose
  

Description: The bomb has an unusual tail unit.  The vanes are short and attached near the end of the tail cone.  The nose of the bomb is more hemispherical than other Italian H.E. demolition bombs.  It is thought that this bomb was designed for use against submarines.

3kg (CV) Antiaircraft Bomb

Overall length: 13.5 inches
Body length: 6.4 inches
Body diameter: 3.2 inches
Tail length: 7 inches
Tail width: 3.2 inches
Type of filling: Amatol
Weight of filling: 0.4 kilograms

Total weight: 3 kilograms

Fuzing: Nose - Type I

  

Color and markings: Overall green; red band on nose

  

Description:  The bomb consists of two containers made of mild steel sheet.  The space between them is filled with steel pellets embedded in concrete.  The nose and the body of the bomb are apparently loaded separately with their filler of concrete and steel.  A brown substance, which tops the nose filling, forms a cushion between the concrete filling.  It appears to be a waterproof composition, containing a resinous wax.

20kg (CV) Antiaicraft Bomb

Overall length: 30.7 inches
Body length: 15.5 inches
Body diameter: 5.5 inches
Wall thickness: 1.1 inches
Tail length: 18 inches
Tail width: 5.7 inches

Type of filling: Unknown

Weight of filling: Unknown
Total weight: Unknown

Fuzing: Nose - Type I

Description: The bomb case is loaded with steel pellets embedded in concrete.  No further description is available.

3.5kg, 5kg, 25kg, 50kg, and 100kg Hollow Charge Bombs

3.5kg
Body length: 18.8 inches

Body diameter: 6 inches
Wall thickness: 0.06 inch
Tail length: 7.7 inches
Tail width: 6 inches
Type of filling: RDX/TNT
Weight of filling: 2.2 kilograms
Total weight: 3.5 kilograms (approx.)
  

Fuzing: Tail fuze for hollow-charge bombs

Description: All these bombs are very similar in appearance, except the 25kg which differs slightly.  The 25kg has the bomb casing of helically wound steel strips.  The 3.5kg was the only bomb of this type known to be used or manufactured by the Italians.

This bomb has a dome-shaped nose completely empty of any main filling and threaded at its base to screw over the threaded cone-shaped body.  The main filling is 60% RDX, 38% TNT, and 2% wax, which is separately cast and is an easy fit in the bomb body.

This main filling has the hollow dome-shaped recess at its base and has fitted to its apex an RDX booster pierced to receive the fuze and its booster.  A horizontal suspension lug is riveted to the body, and a safety pin holder is riveted to the tail vane to receive the safety pin of the fuze.

Bomb Container

Overall length: 5 feet, 6 inches
Body length: 2 feet 8.5 inches
Body diameter: 11 inches
Wall thickness: 0.047 inch
Tail length: 22 inches
Tail width: 11 inches (approx.)

Type of filling:
-40 x 2kg Anti-Personnel F or Mtr.; or
-40 x 1kg Incendiary; or
-20 x 2kg Incendiary; or
-24 x 4kg Anti-Personnel Thermos

Weight (empty): 23 kilograms

Description: This is a metal container holding eight columns of anti-personnel or incendiary bombs.  The body is cylindrical and is of sheet metal.  It contains eight longitudinal tubes which are welded to the after closing plate and the forward closing plate holes in the latter leave the forward ends of the tubes open.  A flap, which is hinged to this plate, partly closes these holes.  The container is held closed by a ball locking the adjustment of which can be observed through the inspection hole.  The forward end of the bomb is closed by an aluminum cap held on by three clips.  Riveted to the inside of this cap is a plate.  Ejector springs are fitted in the after ends of the tube.

The tail cone, carrying four fins, is fitted by screws to the body.  A corrugated ring strut strengthens the tail fins.  Below the drum and situated between each pin of adjacent fins is a drogue of pressed steel.  Each of these drogues is connected to its neighbor by a fabric web fixed to the sides of the drogue by rivets.

A fabric-covered elastic strip attached to each case at one end to the drogue, and at the other end to the drum, tends to pull each drogue open.  The range of movement of each drogue is limited by the length of a flexible wire cable fixed to the tail cone.  Before dropping, these drogues are prevented from opening by a cord or wire which encircles them and passes through a cutter.  This clockwork is prevented from running by a safety pin.  To the underside of this particular drogue is attached an additional cable which runs through a hole in the tail cone, between the main body and inner tubes, and terminates in a bolt, the withdrawal of which releases the ball locking device.  A transit safety pin prevents withdrawal of the bolt.

Operation: On loading into the aircraft, the transit pin is withdrawn.  On release, the safety pin in the clockwork is withdrawn.  After the preset time, varying between 0 and 20 seconds, the clockwork activates a cutter which severs the restraining wire and so allows the drogues to open.  This causes the bolt to be withdrawn.  The springs eject the bombs by forcing open the flap which, in turn, throws off the cap by pressing on the plate with the cap.





Parachute Flares
  

Overall length: 36.9 inches
Flare length: 17 inches
Body diameter: 4 inches (approx.)
Tail length: 14.2 inches

Type of filling: Magnesium Powder
Weight of filling: Unknown
Total weight: Unknown
  

Fuzing: Nose fuze - Type L
  

Description: The bomb consists of a light metal nose, a thin cylindrical body filled with magnesium powder, and a tail unit containing the parachute and release mechanism.  The flare is set for height by means of an indicator on the parachute release mechanism.  On release from the plane, the vanes of both the release mechanism and the nose fuze rotate; the fuze arms, and, when the parachute release mechanism functions to cause the parachute to open, the jerk is sufficient to operate the nose fuze.  The resultant explosion blows away the light metal nose, with the fuze from the cardboard magnesium container, setting off the ignition powder, which, in turn, ignites the magnesium.


Parachute Flares (Cardboard)
  

(No Picture Available)

Overall length: 12.5 inches
Body diameter: 1.45 inches
Wall thickness: 0.19 inch

Type of filling: Unknown
Weights: Unknown

Fuzing: Friction igniter in nose

Color and markings: Overall bright red
  

Description: This flare is contained in a cardboard tube the same thickness throughout its length.  A corrugated cardboard 3.9 inches long surrounds the tube near the center to form a grip.  Below the grip the tube is constructed to fit into the groove in the wooden plug at the nose and is held by a wire.  The open ends of the tube are sealed by paper gummed over.  In central hole of the wooden plug is a friction igniter.  This consists of a friction composition attached to the end of a short length of string impregnated with a phosphorus composition.

The flare operates by breaking the seal at the nose end and pulling the string, which ignites the friction composition.  This, in turn, ignites the safety fuse, which gives approximately two seconds before igniting the powder charge located below the candle.  The charge ignites the candle and at the same time ejects the candle and parachute from the tube.  The resistance to the expelling charge is provided by a felt washer and waste packing at the top of the tube.

Next Time: Italian Projectiles

Italian Explosive Ordnance - Bombs (Part 4)

Italian Explosive Ordnance

100kg Special Bomb Combination Anti-Personnel Bomb and Bomb Container

Overall length: 53.2 inches
Body length: 29 inches
Body diameter: 10.7 inches
Wall thickness: 0.07 inch
Tail length: 20.8 inches
Tail width: 10.7 inches

Type of filling: TNT

Total weight: 113 kilograms or 82.1 kilograms

Fuzing:
-Nose: Type X
-Tail: Type Z

  

Color and markings: Overall reddish brown; red nose

Description:    This is a composite which comprises: (1) 32 small Spezzine bombs; (2) a central bomb; and (3) a nose charge which acts as an anti-personnel bomb.  If Spezzine bombs are filled with H.E., the bomb is called 100kg Sp. I. in the latter, the 32 small bombs (1-kg I) may be replaced by 16 (2-kg I) bombs.

Nose fuze (Type X) functions at a preset height and causes the conical nose portion, carrying a length of burning safety fuze and an explosive charge enclosed in concrete, to fall away and explode subsequently; small bombs thus released fall independently.  The main body continues its flight, containing the central bomb, which explodes on impact under the action of the tail fuze.

The container part consists of two concentric sheet-steel cylinders, the outer 0.08 inch thick and the inner 0.04 inch thick, held together by four strips and the end plate.  The tail is attached to the outer cylinder by four threaded studs; in the inner cylinder is fitted the central bomb, of the "Mitroglia" type.  The nose protrudes and is attached by a steel adapter and locking-ball device to the central bomb.

Spezzine bombs are packed, with safety pins removed, in eight columns of four; each column has a conical spring to keep it in compression.  Under one spring is a spring-loaded plunger, protruding through the end plate and acting as a safety pin for the Fuze Type Z of the central bomb.

 

15kg Gas Bomb

Overall length: 31 inches
Body length: 20.7 inches
Body diameter: 4.7 inches
Tail length: 13.8 inches
Tail width: 6.3 inches

Type of filling: Diphenyl Chlorarsine

Weight of filling: 3.65 kilograms
Burster used: TNT
Weight of burster: 1.7 kilograms
Total weight: 16 kilograms (approx.)

Fuzing: Tail - Unknown
   

Color and markings: Overall yellow; Geneva cross stenciled on the body
  

Description: The bomb is thick-walled with a steel body and nose cast in one piece, to which a dome-shaped base it attached.  Sheet-metal tail fins are attached to a metal band clamped around the body.

Remarks: This bomb is thought to be the same as the 15kg S.A.P. except for filling.

25kg Gas Bomb (Furretta)

Overall length: 32.7 inches
Body length: 30.1 inches
Body diameter: 6.3 inches
Type of filling: Lachrymator
Weight of filling: 10 kilograms

Total weight: 25 kilograms

Fuzing: Tail - Type K

  

Color and markings: Overall yellow; Geneva cross in red

  

Description:  The bomb has a blunt nose and parallel sides, but no tail or stabilizing fins.  This is a percussion bomb; but it functions as a tear-gas generator.  There is no burster charge, but the casing is pierced with small holes through which the lachrymator is emitted.

40kg Gas Bomb C40P

Overall length: 32.3 inches
Body length: 21.4 inches
Body diameter: 9.9 inches
Tail length: 16.1 inches
Tail width: 9.9 inches

Type of filling: Diphenyl Chlorarsine

Weight of filling: 6.5 kilograms
Weight of burster: 13 kilograms
Total weight: 47 kilograms

Type of filling: Mustard Gas

Weight of filling: 14.7 kilograms
Weight of burster: 0.18 kilograms
Total weight: 40.6 kilograms

Fuzing: Tail only - Unknown

  

Color and markings:
-Diphenyl Chlorarsine: Overall yellow; Geneva cross stenciled in black
-Mustard Gas: Overall yellow; red nose; red stenciled marking (see below)

N 2226
Lorpo KG 359; Tara KG179

 
Description: This bomb is similar to 40kg G.P.-H.E. bomb in size and appearance.  The burster tube contains TNT and is about fifteen inches long.  Other information is lacking.

55kg Gas Bomb and 100kg Gas Bomb (C100P)

55kg
Overall length: 32.3 inches
Body diameter: 9.8 inches
Type of filling: Phosgene
Weight of filling: 20 kilograms
Weight of burster: 18 kilograms

Total weight: 55 kilograms

100kg
Overall length: 50.2 inches
Body length: 32.5 inches
Body diameter: 10.7 inches
Tail length: 20.8 inches
Tail width: 10.7 inches
Type of filling: Diphenyl Chlorarsine
Weight of filling: 14.3 kilograms
Weight of burster: 28.7 kilograms

Total weight: 101.9 kilograms

Fuzing:
-55kg: Unknown
-100kg: Tail only; probably C-1 or Y-1
   

Color and markings:
-55kg: Overall yellow; Geneva cross stenciled in white
-100kg: Overall yellow; Geneva cross stenciled in black


Description: These bombs are similar to same weight G.P.-H.E. bombs.  Little information has been found on them.

250kg and 500kg (500T) Gas Bombs

250kg

Overall length: Unknown
Body length: 57.5 inches
Body diameter: 18 inches
Wall thickness: 0.12 inch
Type of filling: Mustard Gas
Weight of filling: 214 kilograms (approx.)

Total weight: 264 kilograms (approx.) without tail

500kg

Overall length: 96.6 inches
Body length: 54.3 inches
Body diameter: 18 inches
Wall thickness: 0.12 inch
Type of filling: Diphenyl Chlorarsine
Weight of filling: 210 kilograms

Total weight: 298 kilograms

Fuzing:
-250kg: Nose - Unknown
-500kg: Nose - Type T

Color and markings:
-250kg: Overall light blue-grey; yellow nose plug
-500kg: Overall grey; Geneva cross, probably in green, above the lettering S.C.M. 1-37 C-500T

Description: These two bombs are thought to be the same except for the slight differences in length of the body, which could have been measured erratically.  Two different illustrations are shown; one is made from recovered bomb and the other is from Italian drawings.

-250kg: The casing is of thin sheet metal and is of welded construction.  Inside the body casing is a baffle for the chemical filling.  The tail unit was not recovered, but could take the alloy tail unit which is used in the C500T.

-500kg: Very little is known about this bomb, since it was not used in the war.  The bomb is very similar to the 500kg General Purpose, except that is has a baffle plate in the center.





5kg Vento Marker
  

Overall length: 17.4 inches
Body length: 8.9 inches
Body diameter: 5.2 inches
Wall thickness: 0.3 inch
Tail length: 9.2 inches
Tail width: 7 inches

Type of filling: Smoke or Incendiary
Weight of filling: Unknown
Total weight: 5.2kg

Fuzing: Nose fuze - Type S

Description: The body consists of a thin metal cylinder liner and outer concrete bomb body, which is reinforced with sheet pellets and wire.  The body liner has welded to it: (1) the suspension lug socket which is internally threaded to receive the horizontal suspension lug; (2) four metal vane support which have riveted to them four aluminum-alloy vanes; (3) two pairs of diametrically opposite wire guides for the base plug retaining wire; (4) the ends of a helical reinforcing wire, 16 S.W.G., which is coiled in three turns and passes through the holes provided in the vane support; and (5) the upper end of a second helical reinforcing wire, 8 S.W.G., which is coiled in five turns and is welded at its other end to the fuze pocket.

At the upper end, the liner is closed by a cork plug.  This bomb is used in conjunction with chemical bombs.  The purpose is to indicate the force and direction of the wind at ground level.  Two main fillings are used, a smoke filling for use in the daytime, and an incendiary filling for use at night.  The night filling is the 1kg Incendiary Bomb Type II.  Another modification of this bomb has no body liner but is all concrete and is used for practice.

Next Time: Italian Gas Bombs and Others

Imperial Japanese Explosives - Land Mines and Grenades (Part 2)

Imperial Japanese Explosives

  

  

Type 3 (a) Antivehicular and Antipersonnel Land Mine
 

Diameter: 8.6 inches

Height (w/o fuze): 4.13 inches
Height (fuzed): 6.2 inches
Length of fuze: 2.5 inches

Material of mine wall: Terra cotta
Thickness of wall: 7/16 inch

Explosive fillin: Type 88 explosive.  Captured document states bursting charge might also be either ammonium nitrate (50%), TNT (50%); or ammonium nitrate (90%), dinitronaphthalene (10%)

Weight of explosive: 4 pounds, 8 ounces

Total weight of mine: 11 pounds, 6 ounces

  

Color and markings: Brown


Description: The mine is circular with a slightly concave top and a moderately convex base.  The mine case is made of earth-colored terra cotta.

The outer surface has a thin dull glaze while the inner surface is covered with a thin coat of lacquer.  A rubber fuze seat is sealed in place in a hole in the center of the top of the mine.  The explosive filler is contained in a light rubber bag inside the mine.

The fuze body, cover, plunger, and striker support are made of bakelite.  The springs, percussion hammer, striker, and the release fork are the only metal parts in the mine and with the exception of the release fork, all are contained inside the fuze.
 

Employment: May be used as an antivehicular or antipersonnel mine.
 

Operation: The mine is place in the desired location and the safety pin is withdrawn.  The fuze may then be rigged to fire either by pull or pressure.

The percussion hammer located within the fuze is held in place by a release fork to which a trip wire may be attached.  When the wire is pulled (22-pound pull required), the fork releases the hammer which is forced downward by the hammer spring.  The hammer hits the striker forcing it through its bakelite holder into the percussion cap.

When pressure of 20-25 pounds is applied directly on the head of the fuze the plunger spring and hammer spring are compressed causing the hammer head to exert pressure on the hammer release fork.  When the plunger is further depressed a groove in its inner surface comes down to the level of the hammer release fork.  The pressure of the hammer head cams out the fork.  The hammer is released and hits the striker which in turn pierces the detonator.

Remarks:  A larger model of this mine exists, and differs from it only in size.  The larger version has a diameter of approximately 10 and 1/2 inches.

  

  

Type 3 (b) Antivehicular and Antipersonnel Land Mine

Diameter: 7 and 1/8 inches

Height (w/o fuze): 5 inches
Height (fuzed): 7.5 inches

Material of mine wall: Wood
Thickness of wall: 9/16 inch

Explosive fillin: Type 88 explosive.  Captured document states bursting charge might also be either ammonium nitrate (50%), TNT (50%); or ammonium nitrate (90%), dinitronaphthalene (10%)

Weight of explosive: 4 pounds, 8 ounces

Total weight of mine: 6 pounds, 4 ounces (w/o fuze)

  

Color and markings: Unpainted wood

   

Description: The mine is simply a wooden box with dovetailed sides to which top and bottom closing pieces have been fastened by screws and nails respectively.  It is a standard mine manufactured to standard specifications and employing the Type 88 explosive charge and its rubber container, the threaded rubber fuze seat, and the same type fuze used in the Type 3 (a) land mine.

The threaded rubber fuze seat is nailed to the bottom side of the top closing piece beneath a hole provided to allow insertion of the fuze.

Employment: May be used as either antivehicular or antipersonnel mine.

Operation: Same as Type 3 (a) land mine.

Beehive Antipersonnel Land Mine

    

Diameter at base: 8 inches

Height (w/o fuze): 4.5 inches
Total weight: 17 pounds (approximate)
Thickness of mine wall: 3/8 inch

Explosive filling: TNT
Weight of explosive: 5 pounds (approximate)

 

Color and markings: Black
  

Description: The mine is hemispherical in shape and its surface is uniformly serrated.

The central hole in the top of the mine is internally threaded to receive one of two fuze adapters.  The first adapter takes either the plastic fuze used in the Type 3 (a) ceramic and Type 3 (b) wooden land mines, or the Type 88 instantaneous artillery fuze from which the centrifugal detents have been removed.  The second adapter is constructed to take the fuze employed in the Type 93 tapemeasure mine.

Both the serrations of the mine case and the thickness of the wall (3/8 inch) indicate that this mine was to be used as an antipersonnel weapon.

Employment: Antipersonnel mine

Operation: The operations of the Type 93 land mine fuze and the Type 3 (a) ceramic land mine fuze are discussed under their respective mines.

The Type 88 artillery projectile fuze from which the centrifugal detents have been removed is fired by pressure on the firing pin head.  Pressure on the firing pin head compresses the anticreep spring and the firing pin is forced into the primer.

5kg Hemispherical Antitank Land Mine

 The 5kg hemispherical A/TK mine is a weapon designed to help overcome the shortage of A/TK weapons and armored vehicles which the Japanese forces experienced during the war.  It is a suicide weapon, intended to be placed against an armored vehicle either by hand or by means of a pole or lines.

The mine is hemispherical in shape, black in color, with the fuze mounted opposite the flat face.  It is equipped with a straight projection to which a pole may be lashed, and with four eyelets to which lines may be attached.

The mine is detonated by the same fuze as that used in the Type 99 magnetic A/TK mine.  No specimens of this mine were found outside of the Japanese homeland, very few of them having been produced.

    

Bangalore Torpedo and Igniter

  

Dimensions: See Drawing
Total weight of torpedo: 10 pounds

Weight of filling: 3 pounds
Type of filling: TNT (36.4%), Cyclonite (63.6%)


Color and markings:
-Torpedo tube: Brown with red band onboard of externally threaded end, white triangle near midepoint of tube, and eleven inches inboard of red band on opposite side from white triangle is (see below)

  

Description:  The igniter system consists of two pull igniters screwed into an igniter holder which fits into the igniter locking collar.  The rings of the igniters are connected by lines to the lanyard holder.  The igniters are simple match composition pull igniters with a black powder delay of 8 seconds, an initiant, and a base charge of tetryl.  When shipping, the steel nose cap is threaded onto the igniter as shown in drawing.

The torpedo proper is a steel tube with shoulders welded to both ends.  One end is internally threaded to take the igniter locking collar and the other end is threaded externally to take the pointed nose cover.  When shipped the tube has a cap screwed over one end and a male plug threaded into the other.

Employment: The Bangalore torpedo is used by the Japanese to demolish barbed wired entanglements.  It can also be used as a booby trap, actuated by pull.

Operation: The caps are removed from the ends of the tube, the pointed nose cover is screwed onto one end, and the igniter locking collar into the other end.  The torpedo is now ready for use.  When the torpedo is placed the safety pin is removed and the firing lanyard is pulled sharply.  Personnel can take cover in the 8 seconds delay period.

The pulling of the firing lanyard pulls the match composition through the abrasive.  The flash starts the black powder which after 8 seconds delay fires the initiant and tetryl base charge and the torpedo charge.




Pressure and Traction Land Mine
  

Overall length: 12.5 inches
Overall width: 9.5 inches
Overall height: 7 inches

Weight of filling: 2 pounds
Type of explosive: Three blocks picric acid or TNT detonator of igniter inserted in center block.



Description: The mine consists of a wooden box, the lid of which is held in place against the internal flanges on the top by four stout springs (one in each corner).  A wooden block is secured by two bolts to the underside of the lid and serves to operate the pull igniter by pressure exerted on the cover.

The explosive charge is in a separate container with the igniter and detonator inserted in the center block.  A pull wire extends from the igniter over to the wire rod directly under the wooden block attached to the underside of the lid.

To this wire rod are attached a trip wire which passes out through the cover to be secured to a tree or other suitable object and an antilifting wire attachment which passes through a hole in the base of the box and is secured to a peg.  The igniter contains ignition composition and a pellet of powdered glass in red cement.

Employment: Used as an antitank or antipersonnel mine.

Operation: The mine will function by either of three methods:
-Pressure exerted on the lid,
-Tension exerted on the trip wire; or
-By lifting the mine to operate the antilifting device.

In all instances the wire rod is moved which pulls the wire leading to the igniter.




Friction-Fuzed Land Mine
  

Overall length: 13 inches
Overall width: 3 inches
Overall height: 2.37 inches

Weight of filling: 3.5 pounds

Type of explosive: Five blocks picric acid or TNT detonator of igniter inserted in end block.

Description: The mine consists of a wooden box, the sides of which are 0.59 inch thick.  A wooden partition block inserted 4.25 inches from the unfilled end of the box serves to hold the five blocks of explosive in place and also to secure the igniter in position.  To the igniter is attached a trip wire which extends out through the end of the box and is secured to a tree or other suitable object.

A safety device, the exact nature of which is unknown but reported to consist of a bottle cap, is incorporated on the outside of the box at a point of egress of the trip wire.  The antilifting device consists of a wire attachment which passes through the base of the box and is secured to a peg driven in the ground.

Employment: The mine is buried 1 to 2 inches below the surface and used as either an antitank or antipersonnel mine.

Operation: The mine can function by either a tension exerted on the trip wire or by lifting the mine to operate the antilifting device.  In both instances the pull igniter is fired which in turn detonates the explosive charge.




Improvised Land Mine
  

Dimensions: A box 5 and 5/8 by 4 and 1/4 by 3 and 1/4 inches
Material: Tin
Color: Silver
 
Description: The mine consists of a rectangular box with a cover securely fastened by friction tape.  Two holes are roughly punched in the cover through which a grenade fuze or detonator projects.  The grenade fuze projects approximately 3/4 inch, projection of detonator is unknown.

Contained in the box are one Japanese Type 91 hand grenade and twelve blocks of 1/3 aluminum powder and 2/3 RDX.  Each block is 1 and 1/2 inch by 3/4 inch and wrapped in waxed paper.  Color is black.  The grenade and blocks, 1/3 aluminum powder and 2/3 RDX, are firmly held in place by waxed paper.

Employment: Can be used as an antitank mine when fuzed with the armed grenade.  With a pull or tension detonator it can be used as an antipersonnel mine or booby trap.

Operation:
-As an antitank mine: Safety pin on fuze is removed.  When it is hit by a sharp blow the striker breaks a shear wire and penetrates the primer.  After a delay of 4 to 5 seconds the bursting charge explodes setting off the charge.

-As an antipersonnel mine or booby trap: A pull igniter with detonator is inserted into the charge.  When the trip wire is pulled, the flash will fire the detonator which in turn sets off the explosive and hand grenade.

Next Time: More Imperial Japanese Land Mines, and Grenades

Imperial Japanese Navy Explosives - Bombs (Part 7)

Imperial Japanese Navy Explosives

5kg Parachute Flare Model 2 Modification 1

 

Fuzes: Pull igniter

Overall Length: 25 and 1/8 inches

Diameter: 3 and 1/8 inches

Material of wall: Light sheet steel
  

Type of suspension: None

Suspension lug: Thrown by hand from plane

 

Type of filling: Illuminant

Weight of filling: 5 pounds 8 ounces

Total weight of flare: 10 pounds 3/4 ounce

Composition of illuminant:
-Barium nitrate: 55.5%
-Aluminum, powdered: 11%
-Magnesium, powdered: 18%
-Wax: 9.1%
 

Color and markings: Body is grey overall.  Two labels give description and instruction for use.
 

Construction: The flare case is cylindrical and of light sheet steel construction.  It contains an illuminating candle unit and a parachute, and is closed at both ends by metal caps.  The cap on the parachute end may be removed by pulling a tear strip.

The illuminating candle unit container is cylindrical in shape and is made of corrugated sheet tin.  A copper tube extends the length of the unit and the illuminant is cast around it.  A wooden plug is fitted into the top of the flare and is held there by a metal cap and several screws.

The fuze is inserted in a hole in the plug and fits down into the copper tube.  Four black powder impregnated strips are attached to the fuze and extend down the copper tube to the base of the illuminant.  Similar black powder strips are cast in the bottom of the flare.  A wooden ring in the base of the candle unit holds it away from the bottom of the flare containers.

The fuze used is of the pull igniter type.  A tin cylinder fits over the end of the fuze and extends up through the parachute to the end cap.  The pull cord attached to the catch on the fuze is led up through the tin cylinder to the end cap.

The parachute is made of silk and is attached to the candle unit by a length of wire rope.  The wire rope is spliced and the two ends are attached to two eyes fastened to the wooden plug in the end of the illuminant container.

Operation: The tear strip is pulled and the end cap removed.  Then the igniter cord is pulled and the flare is thrown from the plane.  The striker in the fuze hits the primer which ignites the powder train.  This burns slowly down to the black powder strings cast in the base of the illuminant, igniting the illuminant.  The expanding gases expel the candle unit and the parachute from the container.  The unit burns for approximately 1 minute and 30 seconds giving off a brilliant white flame.

 

 

 

Type 0 Parachute Flares Model 1 and Model 1 Modification 1
 

 
Fuzes: D-3(a), D-4(a)

Overall Length: 42 and 1/2 inches

Length of body: 39 and 1/2 inches

Diameter of body: 6 and 3/4 inches

Thickness of wall: 3/64 inches

Material of wall: Sheet Steel
 

Type of suspension: Horizontal

Suspension lug: Normal Navy suspension lug

Length of tail: 14 and 3/4 inches
Width of tail fins: 1 and 13/16 inches

Dimensions of tail struts: None

Material of tail: Sheet Steel
 

Type of filling: Illuminant (silver-grey in appearance)

Weight of filling: 66 pounds

Total weight of bomb:
-Model 1: 84 pounds
-Model 1 Modification 1: 88 pounds
 

Color and markings:
-Model 1: Grey overall with 1/4-inch red stripe just below the end piece
-Model 1 Modification 1: Grey overall with a 1/4-inch red stripe just above the end piece and a 1/2-inch white stripe around the body.
 

Construction: The flare consists of three main elements: (1) the flare case, (2) the illuminating candle unit, (3) the parachute.

1. The flare case consists of three sections: a nosepiece, body, and end cap.  The nosepiece is soldered securely to the body, and the hemi-spherical end cap is held in position by spot soldering in four places.  Four tail fins are welded to the after two-fifths of the body.  A steel ring 1 inch wide fits around the body at its junction with the tail cone.  It is attached to the fins and serves to brace them as well as to retard the velocity of the flare's free fall.  The nose is threaded to receive the fuze.

2.  The illuminant is contained in a cardboard canister which is covered by sheet brass 0.025 inch thick.  The after end is closed by a steel plate held by screws to the cylinder.  A 1/4-inch wire rope 65 inches long from which the candle unit is suspended is attached to this steel plate by means of a shackle.  The forward end of the container is open and fits against a wooden block in the nosepiece.  The illuminant at the opened end contains in its center an ignition charge 3 inches in diameter and 1/4-inch thick.

Length of illuminant container: 26 inches
Length of illuminant: 24 and 1/2 inches
Diameter of illuminant: 5 and 1/2 inches

3.  Model 1: A single silk parachute is housed in the after end of the body.  It is surrounded by a layer of cardboard to insure smooth ejection.
 
Model 1 Modification 1: A small guide parachute and a larger parachute are housed in the after end of the body.  They are surrounded by a layer of cardboard to insure smooth injection.
 

Operation: Shortly after being released from the plane the aerial burst fuze operates.  The resultant flash from the magazine ignites the ignition charge which in turn ignites the illuminant.  The expanding gases force the end cap off and eject the parachute and illuminating candle unit.  The flare sheds a bright white light and burns for 3 minutes and 40 seconds.

 

 

 

Type 0 Parachute Flares Model 2 and Model 3 Modification 1

   
Fuzes: D-3(a), D-4(a)

Model 2

Overall Length: 38 and 1/2 inches

Length of body: 35 and 1/2 inches

Diameter of body: 6 and 3/4 inches

Thickness of wall: 3/64 inches

Material of wall: Sheet Steel

Model 3 Modification 1

Overall Length: 42 and 1/2 inches

Length of body: 39 and 1/2 inches

Diameter of body: 6 and 3/4 inches

Thickness of wall: 3/64 inches

Material of wall: Sheet Steel

  
 

Type of suspension: Horizontal

Suspension lug: Normal Navy suspension lug

Model 2
Length of tail: 13 and 1/2 inches

 

Model 3 Modification 1

Length of tail: 15 inches

 

 

Dimensions of tail struts: None

Material of tail: Sheet Steel
 

Type of filling: Illuminant

Weight of filling: 66 pounds

Total weight of bomb:
-Model 2: 84 pounds
-Model 3 Modification 1: 88 pounds
 

Color and markings:
-Model 2: Grey overall with 1/4-inch red stripe just below the end piece
-Model 3 Modification 1: Grey overall with a black stripe around the nose and a 1/4-inch red stripe above the end piece.
 

Construction: The flare consists of three main elements: (1) the flare case, (2) the illuminating candle unit, (3) the parachute.

1. The flare case consists of three sections: a nosepiece, body, and end cap. The nosepiece is soldered securely to the body, and the hemi-spherical end cap is held in position by spot soldering in four places.  Four tail fins are welded to the after two-fifths of the body. A steel ring 1 inch wide fits around the body at its junction with the tail cone. It is attached to the fins and serves to brace them as well as to retard the velocity of the flare's free fall.   The nose is threaded to receive the fuze.

2. The illuminant is contained in a cardboard canister which is covered by sheet brass 0.025 inch thick. The after end is closed by a steel plate held by screws to the cylinder. A 1/4-inch wire rope 65 inches long from which the candle unit is suspended is attached to this steel plate by means of a shackle. The forward end of the container is open and fits against a wooden block in the nosepiece. The illuminant at the opened end contains in its center an ignition charge 3 inches in diameter and 1/4-inch thick.

Length of illuminant container: 26 inches
Length of illuminant: 24 and 1/2 inches
Diameter of illuminant: 5 and 1/2 inches

3. Model 2: A single silk parachute is housed in the after end of the body. It is surrounded by a layer of cardboard to insure smooth ejection.

Model 3 Modification 1: A small guide parachute and a larger parachute are housed in the after end of the body. They are surrounded by a layer of cardboard to insure smooth injection.

Operation: Shortly after being released from the plane the aerial burst fuze operates. The resultant flash from the magazine ignites the ignition charge which in turn ignites the illuminant. The expanding gases force the end cap off and eject the parachute and illuminating candle unit. The flare sheds a bright white light and burns for 3 minutes and 40 seconds.

Experimental Model 11 Parachute Flares

 

Fuzes: D-3(a), D-4(a)

Model 11 Conical

Overall Length: 45 inches

Length of body: 43 and 1/2 inches

Diameter of body: 9 and 1/4 inches

Thickness of wall: 3/64 inches

Material of wall: Sheet Steel

Model 11 Ogival

Overall Length: 46 and 1/2 inches

Length of body: 43 and 1/2 inches

Diameter of body: 9 and 1/4 inches

Thickness of wall: 3/64 inches

Material of wall: Sheet Steel

 

Type of suspension: Horizontal

Suspension lug: Normal Navy suspension lug

Length of tail fins: 13 and 3/4 inches

 

Dimensions of tail struts: None

Material of tail: Sheet Steel

Type of filling: Illuminant

Weight of filling: 68 pounds

Total weight of bomb:
-Model 11 Conical: 106 pounds
-Model 11 Ogival: 110 pounds
 

Color and markings: Grey overall with 1/4-inch red stripe above the end piece
 

Construction: The flare consists of three main elements: (1) the flare case, (2) the illuminating candle unit, (3) the parachute.

1. The flare case consists of three sections: a nosepiece, body, and end cap. The nosepiece is soldered securely to the body, and the hemi-spherical end cap is held in position by spot soldering in four places. Four tail fins are welded to the after two-fifths of the body. A steel ring 1 inch wide fits around the body at its junction with the tail cone. It is attached to the fins and serves to brace them as well as to retard the velocity of the flare's free fall. The nose is threaded to receive the fuze.

2. The illuminant is contained in a cardboard canister which is covered by sheet brass 0.025 inch thick. The after end is closed by a steel plate held by screws to the cylinder. A 1/4-inch wire rope 65 inches long from which the candle unit is suspended is attached to this steel plate by means of a shackle. The forward end of the container is open and fits against a wooden block in the nosepiece. The illuminant at the opened end contains in its center an ignition charge 3 inches in diameter and 1/4-inch thick.

Length of illuminant container: 25 and 3/4 inches
Length of illuminant: 23 and 3/4 inches
Diameter of illuminant: 7 and 3/4 inches

3.  A small guide parachute and a larger parachute are housed in the after end of the body. They are surrounded by a layer of cardboard to insure smooth injection.

Operation: Shortly after being released from the plane the aerial burst fuze operates. The resultant flash from the magazine ignites the ignition charge which in turn ignites the illuminant. The expanding gases force the end cap off and eject the parachute and illuminating candle unit. The flare sheds a bright white light and burns for 4 minutes and 40 seconds.

Type 94 and Experimental Type Modification 1 Float Lights

 

Fuzes: None

Type 94

Overall Length: 11 and 7/16 inches

Length of body: 11 and 7/16 inches

Diameter of body: 2 and 13/16 inches

Thickness of wall: 3/64 inches

Material of wall: Tin Plate

Experimental type, Modification 1

Overall Length: 21 and 3/4 inches

Length of body: 21 and 3/4 inches

Diameter of body: 4 and 3/4 inches

Thickness of wall: 3/64 inches

Material of wall: Tin Plate

Type of suspension: None

Suspension lug: None

Type 94

Length of tail: 2 and 3/4 inches

Width of tail: 3 inches
Width of tail fins: 1 and 3/4 inches
Dimensions of tail struts: None
Material of tail: Tin Plate

Experimental type, Modification 1

Length of tail: 7 inches

Width of tail: 5 inches
Width of tail fins: 2 and 3/8 inches 

Dimensions of tail struts: 5 inches x 3/8 inch x 1/32 inch

Material of tail: Tin Plate
  

Type of filling: Calcium carbide and Calcium phosphide

Total weight of bomb:
-Type 94: 2.2 pounds
-Experimental type, Modification 1: 6.6 pounds

Charge/weight ratio:
-Type 94: 23%
-Experimental type, Modification 1: 33%
  

Color and markings:
-Type 94: Grey with red pull rings.  One paper label
-Experimental type, Modification 1: Chrome yellow.  Red pull rings.  Two paper labels.
 

Construction of body:  In both types the body is constructed of tin plate rolled into a cylinder with soldered lapped joints.  The hemispherical nosepiece and conical tail piece are soldered to the body.  The nosepiece houses a lead weight. 
  
The calcium carbide is contained in the forward part of the body, the calcium phosphide in the after part.  Two metal tear strips cover water inlet holes in the nose and tail.
  

Construction of tail: Four steel fins are soldered to the body and tail cone.  There are no struts on the Type 94.  The fins on the experimental type are braced by a single set of box-type struts.

Operation: The tear strips are removed before dropping.  On impact with the water, the water enters the holes formerly covered by the tear strips.  Water reacts with calcium phosphide to generate phosphine and calcium carbide to generate acetylene gas. 

On contact with the air phosphine ignites spontaneously and the resultant flame is fed by the acetylene which acts as the main source of fuel.

Type 94 Model 2 and Type 0 Model 1 Float Lights

 

Fuzes: None

Type 94 Model 2

Overall Length: 10 inches

Length of body: 10 inches

Diameter of body: 2 and 13/32 inches

Thickness of wall: 3/64 inches

Material of wall: Tin Plate

Type 0 Model 1

Overall Length: 13 and 13/16 inches

Length of body: 13 and 13/16 inches

Diameter of body: 2 and 7/8 inches

Thickness of wall: 3/64 inches

Material of wall: Tin Plate

Type of suspension: None

Suspension lug: None

Type 94 Model 2

Length of tail: 3 and 1/4 inches

Width of tail fins: 1 inches
Dimensions of tail struts: None
Material of tail: Tin Plate

Type 0 Model 1

Length of tail: 4 and 1/8 inches

Width of tail fins: 1 and 5/8 inches

Dimensions of tail struts: 3 and 1/8 inches x 1/4 inch x 1/32 inch

Material of tail: Tin Plate

Type of filling: Calcium carbide and Calcium phosphide
 

Color and markings: Grey overall with two labels posted on body.
 

Construction of body: In both types the body is constructed of tin plate rolled into a cylinder with soldered lapped joints. The ogival nosepiece and conical tail piece are soldered to the body. The nosepiece houses a lead weight.

The calcium carbide is contained in the forward part of the body, the calcium phosphide in the after part. Two metal tear strips cover water inlet holes in the nose and tail.
 

Construction of tail:
-Type 94 Model 2: Three tail fins are soldered to the tail cone.  There are no struts.

-Type 0 Model 1: Four tail fins are soldered to the body and tail cone and are braced by a single set of box-type struts.

Operation: The tear strips are removed before dropping. On impact with the water, the water enters the holes formerly covered by the tear strips. Water reacts with calcium phosphide to generate phosphine and calcium carbide to generate acetylene gas.

On contact with the air phosphine ignites spontaneously and the resultant flame is fed by the acetylene which acts as the main source of fuel.

Remarks: The Type 0 Model 1 float light has a deflector on the exterior of the nosepiece which prevents it from penetrating too deeply into the water.

2kg Smoke Float

  

 

Fuze: Pull Igniter

Overall Length: 18 and 1/8 inches

Diameter of body: 4 and 3/4 inches

Type of suspension: Thrown by hand

Total weight: 4 and 3/4 pounds

Color and markings: White except for yellow nose

Description: A cast-brass nosepiece weighted with lead is soldered to a conical body of 22 gage sheet metal.  A smoke candle unit screws into the nose.  An emission tube, supported by three metal disks, passes lengthwise through the center of the body and has a cork plug in the tail end.  Three rounded tail fins are soldered around the after end of the body.

The smoke candle unit consists of a casing of light alloy containing a smoke-producing composition.  A quick match wich and a length of safety fuse connects the candle with the igniter.  The igniter casing contains a release pin, a spring-loaded striker and primer pressed into a plug which screws into the end of the casing.

Operation: The safety pin is removed and the release pin is withdrawn by pulling on the pull ring.  The striker spring is compressed until the release pin is free of the casing and then the striker is released.  It strikes the primer thus igniting the safety fuse and quick match wick which ignites the smoke composition (after a short delay) which produces a yellow smoke.

Remarks: This smoke float will also be found with a black nose and white body.  When so painted, it contains a black smoke unit.



43kg Smoke Float

 

Fuze: D-3(a) (with vane cups)

Overall Length: 51 inches

Length of body: 35 and 1/2 inches

Diameter of body: 11 and 1/4 inches

Thickness of wall: 1/32 inch

Material of wall: Sheet steel
 

Type of suspension: Horizontal

Suspension lug: Normal Navy suspension lug
 

Length of tail: 15 inches

Width of tail: 13 and 1/2 inches
Width of tail fins: 2 and 3/4 inches

Dimensions of tail struts: None

Material of tail: Sheet Steel

Type of filling: Smoke composition
Weight of filling: 42 pounds (including container)
Total weight of bomb: 94 pounds
 

Color and markings: Gray overall with a 1/4-inch red stripe forward of the end cap.

 

Description: The float consists of five sections: a weighted nose, a conical body, a boat-tailed attachment, an after piece and an end cap.  All parts are soldered solidly together with the exception of the end cap which is held on by four spot solders.  Four fins are soldered to the after piece and boat-tailed attachment.  The fuze pocket is located in the side of the after piece and has an extended opening.

The smoke composition is contained in a tin cylinder running from the nosepiece to a steel ring in the boat-tailed attachment.  A pull igniter, delay train, and quickmatch composition are contained within the smoke unit.

The parachute of light weight white silk is packed compactly in the after piece.  The parachute is secured to a 1/4-inch wire rope which is attached to a shackle on a wooden block.  At the junction of the parachute shrouds and wire rope is a chock absorber 3/8-inch bungee rubber strands.  On the opposite side of the block are two 1/4-inch wire ropes which lead through a second wooden block to a steel ring at the after end of the boat-tailed attachment.

Lashed securely to one of the 1/4-inch cables is a 1/16-inch cable leading to a pull igniter in the smoke container.  A second 1/16-inch cable leads from the shackle on the after wooden block to a small wooden disk contained in the second block.  Around this is a black powder ejection charge.  A third 1/16-inch cable leads from the shackle to a contact on the body at the top of the container.

Operation: When the aerial burst fuze functions, the ejection charge is ignited.  The end cap is torn off and the parachute ejected.  As the parachute is blown out, the pull igniter is actuated and the delay train initiated.

The parachute checks the fall of the flare sufficiently to prevent smashing of the case on impact with the water.  The smoke composition burns from 5 to 8 minutes giving off a grey-black smoke that is heavier than air.

Next Time: IJN Markers, a "Window" bomb, and the Baka Bomb

Imperial Japanese Army Explosives - Bombs (Part 2)

 

 

 

  

Imperial Japanese Army Explosives

 

 

 

 

 

 

Type 3 100kg Skipping Model Bomb

 

  

Fuzes: A-8(a); B-8(a)

Overall Length: 53 inches

Length of body: 31 and 1/4 inches

Diameter of body: 9 and 1/2 inches

Thickness of wall: 2/5 inch

Material of wall: Tubular steel
 

Type of suspension: Horizontal

Suspension lug: Normal Army type hinged suspension lug.
 

Color and markings: Black overall with a red-tipped nose and a yellow band forward of the suspension lug.
 

Length of tail: 21 and 3/4 inches

Width of tail: 13 and 1/4 inches

Width of tail fins: 5 and 7/16 inches

Dimensions of tail struts:
-Forward struts: 9 and 7/16 x 1 and 3/16 x 3/32 inches

-After struts: 9 and 7/16 x 1 and 9/16 x 3/32 inches

Material: Steel
 

Type of filling: Paper wrapped cast picric blocks sealed with TNT

Weight of filling: 98 pounds

Total weight of bomb: 220 pounds

Charge/weight ratio: 42.5%
 

Construction of body: The nosepiece and body are cosntructed of one piece of machined tubular steel.  The after end of the barrel is threaded internally to receive the tail assembly.  The tail cone is welded to a collar which screws into the after end of the barrel.
 

Construction of tail:  Four tail fins are spot welded to the tail cone.  They are braced by two sets of box-type struts.  The tail fins are further strengthened by four steel plates welded to the outer edges and running the entire length from the after end to the curved portion of the fins.  A round hole is cut in each plate to permit access to the tail fuze pocket.

Remarks:  Recent specimens of this bomb incorporate a steel reinforcing section in the after end of the body.  This cylindrical section closed at one end by a perforated plate is strengthened by three strips of metal which divide it into six equal compartments.  Twelve hexagonal bolts around the outer circumference of the bomb hold the section in place.  TNT is cast into the section to a point flush with its after edge.

Type 3 250kg Skipping Model Bomb
   

   

Fuzes: A-8(a); B-8(a)

Overall Length: 78 inches

Length of body: 46 and 1/2 inches

Diameter of body: 11 and 3/4 inches

Thickness of wall: 1/2 inch

Material of wall: Tubular steel

 

Type of suspension: Horizontal

Suspension lug: Normal Army type suspension lug.

 

Color and markings: Black overall with a red-tipped nose and a yellow band forward of the suspension lug.

 

Length of tail: 31 and 1/2 inches

Width of tail: 16 and 1/2 inches

Width of tail fins: 8 and 1/4 inches

 

Dimensions of tail struts:

-Length: 11 and 1/2 inches
-Width: 3/4 inch
-Thickness: 3/32 inch

-Material: Steel
 

Type of filling: Paper wrapped cast picric blocks sealed with TNT

Weight of filling: 230 pounds

Total weight of bomb: 550 pounds

Charge/weight ratio: 41%

 

Construction of body: A steel nosepiece is welded to a tubular-steel barrel.  The after end of the barrel is threaded internally to receive the tail assembly.  A row of 12 hexagonal bolts around the circumference of bomb 3 and 1/2 inches forward of the after end of the barrel hold a steel reinforcing section in place.  This cylindrical section closed at one end by a perforated plate is strengthened by three strips of metal which divide it into six equal compartments.  Twelve holes are drilled in the outer circumference of the section to accommodate the bolts.  TNT is cast in the section to a point flush with its after edges.  The tail cone is welded to a collar which screws into the after end of the barrel.

 

Construction of tail: Four tail fins are spot welded to the tail cone. They are braced by a single set of box-type struts. The tail fins are further strengthened by four steel plates welded to the outer edges and running the entire length from the after end to a point just forward of the curved portion of the fins. A square hole is cut in each plate to permit access to the tail fuze pocket.

Type 4 100kg, 250kg, and 500kg Anti-Shipping Bombs

 

Construction of body: The nose and barrel of the 100kg and 250kg are constructed of 1-piece machined tubular-steel.  On the 500kg, a steel nosepiece is welded to a tubular-steel barrel.  The after end of the barrel is threaded internally to receive the tail assembly.  A row of 12 hexagonal bolts around the circumference of the bomb just forward of the after end of the barrel hold a steel reinforcing plate in place.  This cylindrical section closed at one end by a perforated plate is strengthened by 3 strips of metal bent at a 60 degree angle, which divide it into 6 equal compartments.  Twelve holes are drilled in the outer circumference of the section to accomodate the bolts.  TNT is cast in the section to a point flush with its after edges.  The tail cone is welded to a collar which screws into the after end of the barrel.  Welded to the apex of the tail cone is a burster tube.  This tube contains picric acid and is fitted with a fuze adapter at its after end.

 

Construction of tail: The tail fins are made from sheet steel.  There are two layers of steel in each fin, a single piece having been bent double and the two inner edges welded to the tail cone and burster tube by a continuous weld.  The forward and after ends of the fins are closed by welding.  The tail fins are not supported by tail struts.

1kg Thermite Incendairy Bomb
   

   

Fuzes: Inertia impact fuze

Overall Length: 13 and 1/2 inches

Length of body: 8 and 5/16 inches

Diameter of body: 2 and 1/8 inches

Thickness of wall: 3/8 inch

Material of wall: Magnesium

 

Type of suspension: Cluster container

Suspension lug: None

 

Color and markings: Black overall (prime coat of gold paint on the body only)

 

Length of tail: 5 and 1/8 inches

Width of tail: 2 and 1/8 inches

Width of tail fins: 1 and 1/16 inches

Dimensions of tail struts: 13/16 inch

Material: Light sheet metal

Type of filling: Thermite

Total weight of bomb: 2 pounds 12oz

 

Construction of body: The bomb consists of a nosepiece, incendiary filled body and explosive filled tail.  The nosepiece is made of magnesium and screws into the bomb body.  At the flat forward end it is threaded centrally to receive the brass firing pin holder which contains a fixed steel firing pin.  At the after end it is pierced by a flash hole.  The recess within the nosepiece houses a movable detonator carrier and a creep spring.  An off-center transverse safety pin prevents the detonator carrier from hitting the firing pin.  The body is a thermite-filled cylindrical magnesium tube.  The forward end is threaded internally to receive the nosepiece.  The after end is boat-tailed to accomodate the conical tail cone.  Three-fourths inch aft of the forward end are four vent holes, 90 degrees apart. 
 
The conical tail cone, made of light sheet metal, slips over the boat-tailed after body of the bomb, and is secured to it by four screws.  Each of the three fins, which are made of the same material as the cone, has its inner edge turned and held to the cone by four rivets.  Where the three fins meet aft of the apex of the tail cone, they are braced and held together by angular metal strips, which are riveted onto both sides of each fin by two rivets.  The outer edge of each fin is turned for a distance of 3/4 inch from the after end.  Six rivets hold these turned edges to a circular strut.  Filling the inside of the tail cone is a conical cloth bag containing a pyrotechnic mixture which may have explosive properties.

 

Operation:  The fuze is armed when the safety pin is removed.  On impact the detonator carrier moves down against the crep spring and hits the firing pin.  The resultant flash ignites the thermite filling of the bomb.

5kg Thermite Incendiary Bomb
 

   

Fuzes: Mechanical impact tail fuze

Overall Length: 15 and 3/4 inches

Length of body: 6 and 3/4 inches

Diameter of body: 3 and 11/16 inches

Thickness of wall: 1/8 inch

Material of wall: Welded steel tube

 

Type of suspension: Horizontal

 Suspension lug: 3/4 inch steel band secured around the body by a nut and bolt, 5/16 inch hole drilled in the extension of the band to accept metal hook.

 

Color and markings:
-Bomb Body: Black or olive drab
-Tail: Unpainted tin color

 

Length of tail: 9 inches

Width of tail: 3 and 11/16 inches

Width of tail fins: None

 

Dimensions of tail struts: None

Material: Tin-plated sheet steel
  

Type of filling: Incendiary, consisting of a first fire charge and a main charge

Total weight of bomb: 11 pounds

 

Construction of body: The bomb body consists of a 1/8 inch thick steel tube welded longitudinally and closed at the forward end by a 3/4 inch thick nose plug which is welded in place.  A cylindrical wooden block is fitted part way into the aft end of the body and secured by six countersunk wood screws.  The block contains the simple impact fuze and spring-loaded safety pin and also acts as the connecting element between the body and the tail.  Two 3/8 inch vent holes are drilled longitudinally through the block 180 degrees apart.  The fuze is 2 and 7/8 inches long and has a 1 and 3/16 inch diameter. 
 
The tubular aluminum body contains a striker and a creep spring.  A solid threaded plug closes the aft end and a plug containing the primer screws into the forward end.  A spring-loaded safety pin holds the striker in position.  The incendiary filling in the bomb body consists of a first fire charge which is adjacent to the primer and a main charge below it.  The first fire charge is a compressed black powder composed of magnesium, barium peroxide and potassium nitrate.  The main charge is thermite.

 

Construction of tail:  The tail, consisting of a tinned sheet steel tube closed at the after end, is secured to the wooden block by five wood screws.  The tail and body sections rest flush against one another, completely concealing the wooden block to which they are attached.  A slot in the tail receives the brass safety pin housing which is contained in the wooden block.

 
Operation: When the bomb is released the arming wire is withdrawn, allowing the spring-loaded safety pin to fly out, arming the fuze.  On impact, the striker compresses the creep spring and hits the primer.  The explosion of the primer ignites the first fire charge and the thermite.
 
 
 
 

Type 97 12kg Thermite Incendiary Bomb
 

   

Fuzes: A-2(a) (fitted with a magazine)

Overall Length: 25 and 1/2 inches

Length of body: 14 and 1/2 inches

Diameter of body: 4 inches

Thickness of wall: 3/16 inch

Material of wall: Steel

 

Type of suspension: Horizontal

Suspension lug: Normal Army type suspension lug on barrel, plus an improvised suspension device described below.

 

Color and markings: Black overall with a 9/16 inch white stripe just forward of the suspension lug.

 

Length of tail: 11 inches

Width of tail: 5 and 7/16 inches

Width of tail fins: 2 and 3/16 inches

 

Dimensions of tail struts:
-Length: 3 and 7/8 inches
-Width: 3/8 inch
-Thickness: 1/16 inch

Material: 1/16 inch rolled steel
 
 Type of filling: Three thermite-filled magnesium fire pots.  Two black powder charges

Weight of filling:
-Fire Pots: 10 pounds
-Black powder charges: 11 ounces

Total weight of bomb: 26 pounds

Charge/weight ratio: 38%

 

Construction of body: A cast-steel nosepiece is screwed into a tubular-steel body.  A normal hinged Army suspension lug and an additional suspension device are fitted to the body.  The suspension device consists of two steel bands 11/16 inch wide, each secured around the body by a bolt and nut.  The bands are joined by a steel strip 1/2 inch wide which is welded to them.  A 1/4 inch steel rod formed into a suspension yoke is welded to the steel strip.  A tail cone is welded to a collar which fits into the after end of the body and is held in place by four rivets.

 

Construction of tail:  Four steel fins are welded to the tail cone and are braced by a single row of box-type struts.

Operation:  The fuze is armed in flight and on impact the magazine is fired which in turn ignites the black powder charge.  The flash from this charge travels down a central flash channel igniting the incendiary composition in the fire pots and firing the black powder charge in the tail.  The explosive force of the two black powder charges is sufficient to shear the four rivets at the after end of the bomb body and thus expel the fire pots.

 
Remarks:  The suspension yoke will be found on this bomb only when it is suspended from a balloon.


 

Next Time: Incendiary and Smoke bombs, and Parachute Flares