Monday 25 January 2016

Imperial Japanese Army Explosives - Bombs (Part 4)

 
 
 
Imperial Japanese Army Explosives

 
 
 
 
 
 

Type 97 15kg Concrete Bomb
 
Fuzes: A-2(b) or A-2(d)
Overall Length: 26 inches
Length of body: 17 and 3/4 inches
Diameter of body: 4 inches
Thickness of wall: 1/32 inch
Material of wall: Sheet steel
 
Type of suspension: Horizontal or vertical
Suspension lug: A typical Army suspension lug attached to a steel band around the body.  Another suspension lug is fastened to a pipe which is part of the tail assembly.
 
Color and markings: Black overall.  Red stripe on nose.  Yellow stripe and white stripe forward of suspension lug.
 
Length of tail: 8 and 1/4 inches
Width of tail: 5 and 1/2 inches
Width of tail fins: 2 and 1/4 inches
 
Dimensions of tail struts:
-Length: 3 and 3/4 inches
-Width: 1/2 inch
-Thickness: 1/16 inch
Material: Sheet steel

Type of filling: Cast picric in a central exploder tube surrounded by steel pellets set in concrete.
 
Weight of filling:
-Picric Acid: 3 pounds
Total weight of bomb: 32 pounds
 
Construction of body: The body is constructed of a light sheet steel cylinder which surrounds a steel central burster tube.  The space between the tube and the outercasing is filled with steel pellets set in concrete.  The nose of the bomb is slightly tapered.  A steel adapter ring is welded to the end of the nosepiece.  It is threaded internally to receive another ring which contains the nose fuze pocket.  The central burster tube is an explosive filled 1/8 inch steel cylinder, 2 and 3/8 inches in diameter and 16 and 1/2 inches long.  A base plug is inserted into the after end of the central tube and held in place by a friction fit.
 
Construction of tail:  A steel pipe 7/8 inch in diameter and 9 inches long is welded to the base plug.  Four tail fins are welded to the pipe and to the base plug.  The tail fins are braced by a single set of box-type struts.  A hinged lug for vertical suspension is attached to the after part of the steel pipe.
 




Type 94 10kg Substitute Bomb
 
  
Fuzes: A-2(b)
Overall Length: 27 and 1/2 inches
Length of body: 18 and 1/4 inches
Diameter of body: 4 and 1/8 inches
Thickness of wall: 1 inch (approx.)
Material of wall: Concrete
 
Type of suspension: Horizontal
Suspension lug: Normal Army hinged lug 
 
Color and markings: Black overall with a red band on the nose.  Markings in white: weight, place and date of manufacture.
 
Length of tail: 9 and 1/4 inches
Width of tail: 5 and 1/2 inches
Width of tail fins: 2 and 3/8 inches
 
Dimensions of tail struts:
-Length: 3 and 1/2 inches
-Width: 1/4 inch
-Thickness: 1/16 inch
Material: Sheet steel

Type of filling: Central tube filled with black powder
Weight of filling: 1.2 pounds
Total weight of bomb: 22 pounds
 
Construction of body: The bomb consists of a thick concrete case surrounding a steel central tube.  The tube is filled with loose black powder.  It is threaded internally at both ends.  A steel well containing a nose fuze pocket threads into the forward end of the tube.  A brass disk is placed between the fuze and the black powder.  The after end of the tube is closed by a male base plate.  A length of pipe is attached to the base plate by four screws.
 
Construction of tail:  Four tail fins are welded to the pipe extending from the base plate.  Four single struts support the fins.







Type 1 30kg Substitute Bomb
 
Fuzes: A-2(b), A-2(d); or B-1(a)
Overall Length: 32 inches
Length of body: 20 inches
Diameter of body: 5 and 1/8 inches
Thickness of wall: 1/16 inch
Material of wall: Sheet steel
 
Type of suspension: Horizontal
Suspension lug: A typical hinged Army suspension lug is attached to a steel band which fits around the bomb. 
 
Color and markings: Black overall with a red-tipped nose.  Size and type of bomb are stenciled forward of the suspension lug.  Place and date of manufacture are stenciled aft.
 
Length of tail: 11 and 11/16 inches
Width of tail: 7 inches
Width of tail fins: 2 inches
 
Dimensions of tail struts:
-Length: 5 and 3/16 inches
-Width: 1 and 3/16 inch
-Thickness: 1/16 inch
Material: Sheet steel

Type of filling: Main filling is steel pellets set in concrete.  Central tube contains black powder and high explosive.
 
Weight of filling:
-Explosive filling: 2.8 pounds
Total weight of bomb: 63 pounds
 
Construction of body: The body is constructed of a light sheet steel cylinder which surrounds a steel central burster tube.  The space between the tube and outer casing is filled with steel pellets set in concrete.

The nose section is welded to the barrel.  A steel adapter ring is welded to the end of this section.  The adapter ring is internally threaded to receive another ring which contains the nose fuze pocket.

The central exploder tube contains two tinned steel canisters.  The forward container is filled with black powder.  The larger after container is filled with a high explosive.

The tail cone is welded to the barrel and has a fuze pocket at its apex.
 
Construction of tail: Four tail fins are welded to the tail cone and braced by a single set of box-type struts.
 
Remarks:  The bomb body and tail cone may be pierced by 4 rows of  holes 90 degrees apart.  Each row contains 11 holes which are 1/64 inch in diameter.  It is assumed that the purpose of the holes is to release the moisture and air in the newly cast concrete filling.






Type 95 4kg Practice Bomb
  
 
Fuzes: None
Overall Length: 26 inches
Length of body: 16 and 1/2 inches
Diameter of body: 4 and 13/16 inches
Thickness of wall:
-Concrete nose: 9/16 inch
-Steel body: 1/32 inch
Material of wall:
-Nose: Concrete
-Body: Sheet steel
 
Type of suspension: Horizontal
Suspension lug: Rectangular suspension lug held to the bomb body by a steel eye.
 
Color and markings: Black overall, "4K" marked on the nose.
 
Length of tail: 9 and 1/2 inches
Width of tail: 4 and 7/8 inches
Width of tail fins: 1 and 7/16 inches 
 
Dimensions of tail struts:
-Length: 3 and 1/2 inches
-Width: 3/4 inch
-Thickness: 1/32 inch
Material: Sheet steel

Type of filling: Tannic chloride smoke compound
 
Weight of filling: 6.4 oz
Total weight of bomb: 8.8 pounds
 
Construction of body: The bomb is of three-piece construction consisting of a concrete nosepiece, sheet-steel body and wooden tail cone.  The steel body fits over the after part of the nose and is held there by four screws. 

The nose houses a wooden spindle extension.  A steel shear wire passes through the nose and spindle extension.  A wooden spindle supported by a metal collar fits into the after end of the extension.  The spindle extends the full length of the body and into the tail cone.  The wooden tail is held to the after end of the body by four screws.  It is drilled centrally to accommodate the spindle.

A metal disk with a striker point is nailed to the after end of the spindle.  A perforate steel cylinder is attached to the apex of the tail cone.  This cylinder houses an ampoule containing the smoke compound.  It is held in place by a base plate.  A 1/8 inch steel safety pin fits through the tail cone and wooden spindle.
 
Construction of tail:  Four steel fins are attached to the tail cone by screws and are soldered to the steel cylinder.  The fins are braced by two sets of box-type struts.
 
Operation:  The safety pin is removed and the bomb is dropped.  On impact the nosepiece is crushed and the wooden spindle extension is pushed into the tail of the bomb shearing the shear wire.  The striker point at the end of the spindle breaks the ampoule freeing the smoke compound.
 
 






Type 2 1/3kg Cluster Bomb
 
Fuzes: B-5(a)
Overall Length: 10 and 1/4 inches
Length of body: 4 and 1/4 inches
Diameter of body: 1 and 9/16 inches
Thickness of wall: 1/32 inch
Material of wall: Steel
 
Type of suspension: Carried in clusters of 30 or 76 in a container
Suspension lug: None
 
Color and markings: Body is black with yellow band around center.  The tail extension and tail are grey.
 
Length of tail: 6 inches
Width of tail: 1 and 3/4 inches
Width of tail fins: 7/8 inch
 
Dimensions of tail struts:
-Diameter: 1 and 3/4 inches
-Width: 1 and 1/2 inches
-Thickness: 1/16 inch
Material: Aluminum

Type of filling:
-TNT: 60%
-RDX: 40%
 
Weight of filling: 4 oz
Total weight of bomb: 11 oz
Charge/weight ratio: 37%
 
Construction of body: The cylindrical steel body is crimped around the nosepiece and screwed into the forward end of the tail extension.  An inner cone is found at the forward end of the body which gives a "Monroe Effect" on exploding.  The tail cone which houses the fuze is screwed into the after end of the tail extension.  The booster assembly is contained in the tail extension.
 
Construction of tail:  Three aluminum tail fins are attached to the tail cone by screws.  They are braced by a single hexagonal strut and by a hexagonal end plate. (See modified bomb)
 
Remarks:  Modified Bomb: A container full of modified Type 2 40mm bombs has been recovered.  These bombs are filled with Japanese Army Mark 2 explosive (Tanoyaku - 50% TNT, 50% RDX).  A 5/16 inch layer of pure cyclonite poured in on top fills up the bomb body.
 
Evidently in an effort to reduce UXB's the arming spindle of recent bomb was lengthened about 1/8 of an inch.  This increase allows the cup-shaped vanes to protrude further into the wind stream.
  
The end plate on the modified bombs is omitted.  A 5/16 inch strut at the extreme end of the fins is substituted.  A golden lacquered, thin, tinned steel is substituted for the older type aluminum tail fins.
 
Captured documents describe the use of this bomb in air-to-air bombing.






 
Type 3 1/2kg Cluster Bomb

   
Fuzes: A-6(a) or A-6(b)
Overall Length: 4 and 3/4 inches
Length of body: 2 and 3/4 inches
Diameter of body: 2 and 1/8 inches
Thickness of wall: 3/64 inch
Material of wall: Drawn steel
 
Type of suspension: Carried in clusters of 63 in a container
Suspension lug: None
 
Color and markings: Black overall with 9/16 inch yellow stripe 1/2 inch forward of base and a red band around the nose.
 
Length of tail: 2 inches
Width of tail: 3 inches
Width of tail fins: 1 and 1/8 inches
 
Dimensions of tail struts:
-Length: 2 and 5/32 inches
-Width: 3/8 inch
-Thickness: 1/16 inch
Material: Sheet steel

Type of filling:
-TNT: 58%
-RDX: 42%
 
Weight of filling: 7 oz
Total weight of bomb: 14 oz
Charge/weight ratio: 50%
 
Construction of body: The body consists of a drawn-steel cup to which is welded a cast-steel nose.
 
Construction of tail: Four tail fins are spot welded to the base of the body.  They are supported by a single set of box-type struts.
 
Remarks:  A distinguishing feature of these bombs is the construction which permits fitting the nose of one bomb into the tail of another.  This union of the nose and tail serves two purposes:
 
(1): It prevents the fuze vanes from rotating while in the cluster;
(2): It decreases the length of space needed to contain the fuzed bombs in cluster containers.
 




Type 2 1/2kg Bomb
 
Fuzes: A-7(a)
Overall Length: 4 and 13/32 inches
Diameter of body: 2 and 1/2 inches
Thickness of wall: 3/32 inch
 
Color and markings: Black overall with a red band around the nose.
 
Type of filling:
-TNT: 60%
-RDX: 40%
 
Weight of filling: 8 oz
Total weight of bomb: 14 oz (without fuze)
Charge/weight ratio: 60.7%
 
Description: The bomb assembly consists of a small bomb and fuze, a reel of steel cable, and two parachutes packed in a split can with a hinged bottom and a screw top.  The bomb proper is a steel cylinder closed at both ends.  The walls and base are made in one piece with a smaller extension drawn out from the base to take the base plug.  The nose end is closed by a disk welded onto the walls.  A protruding threaded collar is welded onto the disk.  The cable attachment is threaded to a base plug which screws into the base of the bomb and is held there by a locking nut.

A-7(a) is an all-ways action fuze screwed into the nose collar of the bomb.
 
The parachute assembly consists of the main parachute, attached to the auxiliary parachute, which is attached to the reel containing 164 feet of 1/16 inch diameter steel wire, which is connected to the cable attachment on top of the bomb.

The small auxiliary parachute is 13 and 1/2 inches in diameter unfilled, and is attached to the top of the reel by nine 15-inch silk shrouds.  The main parachute is 36 and 1/2 inches in diameter unfilled.  Thirteen silk shrouds, 37 and 1/2 inches long, are attached to a cord leading out of the top of the auxiliary parachute by 8 and 1/2 inches of double bungee cord.
 
Operation:  This bomb is designed for air-to-air bombing.  Prior to release, the container lid is unscrewed and the safety pin removed from the arming vane.  It is probable that the entire can without the lid is discharged from the airplane.  Air resistance would quickly eject the contents from the container.

As soon as the bomb starts to fall through the air, the parachute opens, the cable partially unwinds, and the arming vane rotates.  Ten revolutions suffice to unscrew the spindle from the fuze body: the vane and spindle then fall away.  The striker and primer are now free in the fuze body, held apart only by a spring.

When the plane strikes the cable, the bomb is either drawn up against the plane or whipped up eventually hitting the plane.  On impact with the plane, inertia causing the fuze parts to move in any direction except toward the nose of the fuze, will cause the striker and primer carrier to be driven together, firing the fuze, and detonating the bomb.
 
Remarks:  Since the fuze is designed not to fire when the bomb strikes on its nose, the bombs may not explode in impact with the ground (if it misses the plane).  Since the spring is quite weak, a highly sensitive and dangerous UXB may be expected.
 
 



Next Time: More cluster munitions and containers

Monday 18 January 2016

Imperial Japanese Army Explosives - Bombs (Part 3)




Imperial Japanese Army Explosives





Type 97 50kg Incendiary Bomb


 
Fuzes: A-2(a) or A-2(b)
Overall Length: 45 inches
Length of body: 1/2 inch  (My book does not include the first number)
Diameter of body: 7 and 1/2 inches
Thickness of wall: 3/16 inch
Material of wall: Steel
 
Type of suspension: Horizontal
Suspension lug: Normal Army type suspension lug.
 
Color and markings: Gray overall.  A yellow and a white band are stenciled just forward of the suspension lug.  There is a red band around the nose.
 
Length of tail: 18 and 1/2 inches
Width of tail: 9 and 3/16 inches
 
Dimensions of tail struts:
-Length: 6 and 3/4 inches
-Diameter: 5/16 inch
Material: Sheet steel
  
 Type of filling: 400-450 rubber bungs (1 inch long by 1 inch diameter) impregnated with phosphorus dissolved in carbon disulphide.  The high-explosive charge in the nose and central burster tube is picric acid.
 
Weight of filling:
-Incendiary Filling: 37 pounds
-Picric Acid: 5.5 pounds
Total weight of bomb: 110 pounds
Charge/weight ratio: 39%
 
Construction of body: A steel nosepiece is held by three grub screws to a steel sealing plate.  The plate is welded to a tubular-steel body by a continuous circumferential weld.  A burster tube threads into the sealing plate and the joint is made airtight by a lead washer.   A tail cone is welded to the after end of the body.
 
Construction of tail:  Four steel fins are welded to the tail cone and are braced by two sets of tubular struts.
 
Remarks:  This bomb case was originally designed to contain gas.



 
 
 
 
 
Type 100 50kg Incendiary Bomb
  
    
Fuzes: A-2(a), A-2(b), or A-2(c)
Overall Length: 40 and 1/2 inches
Length of body: 23 and 3/4 inche
Diameter of body: 7 inches
Thickness of wall: 1/8 inch
Material of wall: Steel
 
Type of suspension: Horizontal
Suspension lug: Normal Army type.
 
Color and markings: Gray overall with a white band forward of the suspension lug and a red band around the nose.
 
Length of tail: 16 and 3/4 inches
Width of tail: 9 and 3/4 inches
Width of tail fins: 4 and 1/2 inches
 
Dimensions of tail struts:
-Length: 5 and 5/16 inches
-Width: 1 and 1/2 inches
-Thickness: 1/16 inch
Material: Steel
  
 Type of filling: 400-450 rubber bungs (1 inch long by 1 inch diameter) impregnated with phosphorus dissolved in carbon disulphide.  The high-explosive charge in the nose and central burster tube is picric acid.
 
Weight of filling:
-Incendiary Filling: 35 pounds
-Picric Acid: 5 pounds
Total weight of bomb: 97 pounds
Charge/weight ratio: 44%
 
Construction of body: A steel nosepiece is held by three grub screws to a steel sealing plate.  The plate is welded to a tubular-steel body by a continuous circumferential weld.  A burster tube threads into the sealing plate and the joint is made airtight by a lead washer.   A tail cone is welded to the after end of the body.
 
Construction of tail:  Four steel fins are welded to the tail cone and are braced by single set of tubular struts.
 
 
 
 
  
 
 
 
Type 100 50kg Smoke Bomb

 
Fuzes: A-2(a) or A-2(b)
Overall Length: 45 inches
Length of body: 23 and 3/4 inches
Diameter of body: 7 and 1/2 inches
Thickness of wall: 3/16 inch
Material of wall: Steel
 
Type of suspension: Horizontal
Suspension lug: Normal Army type suspension lug.
 
Color and markings: Grey overall with a red band around nose. "50K" and the smoke symbol "ケ" are stenciled in white on the bode.
 
Length of tail: 16 and 3/4 inches
Width of tail: 9 and 3/4 inches
 
Dimensions of tail struts:
-Length: 5 and 5/16 inches
-Width: 1 and 1/2 inches
-Thickness: 1/16 inch
Material: Sheet steel
  
 Type of filling: FS Smoke analyzed to be -
-Chloro-sulfonic acid: 41%
-Sulphur trioxide: 54%
-Sulphuric acid: 5%
 
Weight of filling:
-Chemical filling: 35 pounds
-High-explosive filling: 6 pounds
Total weight of bomb: 117 pounds
Charge/weight ratio: 48%
 
Construction of body: A steel nosepiece is held by three screws to a steel sealing plate.  The nosepiece houses a charge of picric acid.  The sealing plate is welded to a tubular-steel body by a continuous circumferential weld.  A burster tube containing picric acid threads into the sealing plate.  A tail cone is welded to the after end of the body.
 
Construction of tail:  Four steel fins are welded to the tail cone and are braced by a single row of box-type struts.
 
 
 
 
 
 
Type 92 50kg Gas Bomb
   
   

Fuzes: A-2(a), A-2(b), or A-2(c)
Overall Length: 45 inches
Length of body: 26 and 1/2 inches
Diameter of body: 7 and 1/2 inches
Thickness of wall: 3/16 inch
Material of wall: Steel
 
Type of suspension: Horizontal
Suspension lug: Normal Army type suspension lug attached to a carrying band.
 
Color and markings: Grey overall with a red-tipped nose and a blue band aft of the red band.  There is a yellow band and white band forward of the suspension lug and a yellow band aft of the suspension lug.
 
Length of tail: 18 and 1/2 inches
Width of tail: 9 and 3/16 inches
Width of tail fins: 4 and 7/8 inches
 
Dimensions of tail struts:
-Length: 6 and 3/4 inches
-Diameter: 5/16 inch
Material: Sheet steel
  
 Type of filling: 50/50 Lewisite/Mustard Gas mixture.
 
Weight of filling: 50 pounds
Total weight of bomb: 110 pounds
Charge/weight ratio: 46%
 
Construction of body: A steel nosepiece is held by three screws to the bomb body.  The nose contains a picric acid burster charge.  A tail cone is welded to the after end of the body; the body and tail cavity is filled with liquid gas.  A central burster charge container is threaded into the forward end of the body.  It houses a firing pin, detonator, booster and a picric acid burster charge.
 
Construction of tail:  Four steel fins are welded to the tail cone and are braced by two sets of tubular struts.
 

 
 
 
 
Type 90 Small Model Parachute Flare
 
  
 
Overall Length of container: 26 and 1/4 inches
Diameter of container: 2 and 7/8 inches
Overall length of flare body: 14 inches
Diameter of flare body: 2 and 7/16 inches
Material of wall: Sheet steel
 
Type of suspension: Thrown by hand from plane.
 
Color and markings: Container is blue overall.  Flare body is a natural steel color
 

 Type of filling: A black powder ignition charge and a main filling of an illuminating composition of barium chlorate (75.2%) and gum (24.8%).
 
Weight of filling: 4 pounds
Total weight of flare: 8 pounds (approx.)
 
Description: Each flare is packed in a blue-tinned steel container which is opened by a tear off strip.  Housed within the container is a split cardboard cylinder closed at one end with a cap and hinged at the other end.  The cylinder contains a parachute and flare unit.  The flare unit consists of a pull igniter, delay train, ignition charge, and illuminating composition in a sheet-steel tube.  The pull ignite wire is attached to the parachute shrouds.

The flare proper houses a pull-type igniter which is activated by the initial jerk at the opening of the parachute.  The striker is spring loaded.  Two arms pivoted on the striker release grip the eye on the end of the striker.  The flare body is formed from varnished sheet steel rolled and soldered into the form of a cylinder.  The case of the flare (furthest from the parachute) is serrated and the teeth crimped over the perforated disk.  Two fiber washers and a steel cap held on by tape protect the network of powder strips.  The end of the central tube passes through a hole in the center of the perforated disk and is crimped over it. 
 
An aluminum casting fits into the central tube and guides some of the powder strips in the disk through grooves in its face over the strips within the ignition tube.  At the top of the flare is a wooden spacer drilled centrally to accommodate the central tube.  A steel closing disk rests on the spacer and is soldered to the end of the central tube.  The case is crimped over this disk.  A conical cap with a hole in the apex to accommodate the pull wire is fastened to the case and spacer with three wood screws.

The main filling extends from the wooden spacer down to the ignition charge and is pressed into the flare case.  Several coils of copper wire around the central tube prevent the filling from falling out of the base when the flare is burning in the air.  The ignition charge is packed unevenly below the main filling.
 
Operation:  The tear strip is removed and the cardboard cylinder slipped out.  The cap is removed from the cylinder, binding tapes untied and the flare is dropped from the plane.  The resultant tug from the opening of the parachute pulls the igniter wire.  The striker hits the cap which ignites the delay train which fires the ignition charge which in turn ignites the illuminating composition.  Several coils of copper wire in the illuminant prevent the filling from falling out of the base while the flare is burning in the air.

 
Remarks:  The flare burns for 2 minutes and 40 seconds with an intense greenish-white flame.
 
 
 
 
 
  
Type 1 12kg Parachute Flare
  

 
 Fuzes: D-5(a)
Overall Length: 37 inches
Length of body: 37 inches
Diameter of body: 4 and 3/16 inches
Thickness of wall: 1/16 inches
Material of wall: Sheet steel
 
Type of suspension: Horizontal
Suspension lug: Normal Army type suspension lug
 
Color and markings: Black overall

Length of tail: 11 and 3/4 inches
Width of tail: 6 and 1/16 inches

Dimensions of tail struts: None
Material of tail: Steel
 
 Type of filling: Illuminant
-Barium Nitrate: 77%
-Aluminum: 8.8%
-Magnesium: 4.4%
-Sulphur: 2.2%
-Paraffin: 4.5%
 
Weight of filling: 15 pounds
Total weight of flare: 27 pounds
Charge/Weight ratio: 57%
 
Description: The cylindrical external case of sheet steel construction is closed at one end by a conical nose piece and at the after end by a wooden conical nose piece and at the after end by a wooden disk.  The nose, threaded to receive a fuze, is filled by a wooden block.  A black powder ignition charge is just aft of the block.  The central body houses a parachute and a candle unit.  The silk parachute is surrounded by a split cylindrical fiber housing.  The shrouds are attached to a 1/8 inch wire roped 53 inches long which is attached to the candle unit.

The illuminant is contained in a sheet-steel cylinder, open at the forward end and closed at the after end by a steel plate.  The open forward end rests on the black powder charge in the nose.  While carried in the plane a safety wire is passed through two eyelets at the tail end of the external case, preventing the parachute from coming out until the flare has been released from the plane.
 
 
Operation:  When the fuze initiates explosion on the black powder charge, the resultant flash ignites the illuminant.  The expanding gases cause both the parachute and the illuminant container to be expelled out the rear of the flare case.  The parachute housing falls away allowing the parachute to be opened.

 
Remarks:  The illuminant burns for 1 and 1/2 to 3 minutes with a greenish-white flame.



 
Type 3 Parachute Flare
    
  
Fuzes: D-5(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 Army type suspension lug
 
Color and markings: Dull red overall

Length of tail: 11 and 1/2 inches
Width of tail: 1 and 7/8 inches

Dimensions of tail struts:
-Width: 1 inch
-Thickness: 1/20 inch
-Diameter: 6 and 3/4 inches
Material of tail: Sheet steel

Length of illuminant container: 26 inches
Length of illuminant: 24 and 1/2 inches
Diameter of illuminant: 5 and 1/2 inches
 
 Type of filling: Illuminant
 
Weight of filling: 66 pounds
Total weight of flare: 84 pounds
 
Construction of body: The flare consists of 3 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 hemispherical 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 flares 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 0025 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 open end contains in its center an ignition charge 3 inches in diameter and 1/4 inch thick. 
 
3. There is a single silk parachute housed in the after end of the body.  It is surrounded by a layer of cardboard to insure smooth ejection.
 
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 illuminant candle unit.

 
Remarks:  The flare sheds a bright white light and burns for 3 minutes and 40 seconds.




Next Time:  Concrete, practice, and cluster bombs.

Monday 11 January 2016

Soviet Satellite Country Ammunition - Communist China (Part 1)

 
 
 
Examination of Communist Chinese Ammunition Production/Inventory



 
Communist China

 
Perhaps the most evident generality descriptive of Chinese Communist ammunition is that it is a heterogeneity of foreign designs.  Ninety percent of all weapons and ammunition in use are of foreign manufacture.
At the conclusion of World War II, quantities of Japanese ammunition fell into Chinese Communist hands; later, in the struggle for control of the Chinese mainland, a goal attained in 1949, large Chinese Nationalist stocks were captured and Nationalist arsenals were seized.  Arsenals originally built by the Japanese for their own use continued to produce Japanese ammunition under the Nationalists and their successors, the Chinese Communists.  Soviet ammunition was received in increasing quantities from the start of the Korean War in 1950, and, with captured United States ammunition, was a mainstay of the Chinese Communist war effort in Korea.
 
Over the years, ammunition of British, Swedish, French, Italian, and German origin also found its way into China in varying amounts, and is now in Communist depots.
 
The Chinese Communists have striven to construct new armament plants, and to rebuild and expand the former Nationalist arsenals, which are now their major native source of munitions; the Soviets have assisted them by providing equipment and technical advice.  When, or whether, the native industry will attain a production capacity that will free Communist China of dependence on imported munitions, is not know.  This matter would involved industrial proportions that are not apt to be realized in the neat future, however.
 
For some years to come, then, Chinese Communist Army ammunition probably will be of foreign origin to a large extent, with the most important supplier continuing to be the USSR.  Ammunition of Chinese Communist manufacture is expected to become increasingly significant, and is likely to consist almost entirely of straight or modified copies of foreign designs, again most commonly displaying Soviet influence.
 
 At present, the quality of the native products is erratic - sometimes good, sometimes poor.  There are a variety of reasons for the shortcomings, among them: Loose manufacturing standards; lack of an adequate force of skilled workers; unsatisfactory machinery; and shortages of raw materials.  Deficient packaging is not unusual, and frequently results in serious deterioration of originally undefective contents.  Efforts to improve quality will most certainly be made, and in time will probably succeed.

 
Glossary of Chinese terms


  






A. Small Arms Ammunition
 


Although Communist China has sufficient manufacturing facilities to fill her peacetime requirements for small arms ammunition, the Korean War showed that the country could not produce the quantities needed in wartime.  The Chinese Communists used Soviet and captured U.S. ammunition extensively in Korea.

China has manufactured United States .45 cal M1911 pistol cartridges and .30 cal M2 ball ammunition in the past, but no specimens definitely proven to be of Chinese Communist origin have been recovered.  Reports of the rebarreling of .30 cal weapons to 7.92mm suggest that the Chinese may be standardizing on 7.92mm rifles and machineguns.

Standardization between China and the USSR is limited in the field of small arms.  The Chinese Communists manufacture copies of both the Soviet 7.62mm Model PPSh-41 submachinegun and the Soviet 7.62mm Model TT1933 pistol, which they call the Type 50 and Type 51, respectively.  They also manufacture ammunition for these weapons.  They are not known to manufacture any other Soviet types of weapons or ammunition in the small arms class.

Two types of Chinese-made cartridges which are not covered in detail in this pamphlet are the 7.92mm reduced-charge cartridge and the 7.92mm conical-nosed ball.  The reduced-charge cartridge, except for its lighter propellent charge, is the same as the standard 7.92mm pointed ball.  It was manufactured specifically for certain Chinese-made Czech ZB-26's which, being constructed of inferior metal, could not withstand the pressures of the standard cartridges.  The conical-nosed 7.92mm ball is modeled on the German M1888 ball and is intended for the German M1888 service rifle and Chinese copies of that weapon.  Its propellent charge is lighter than that of the standard 7.92mm pointed ball, and its bullet diameter is smaller: 0.318 inch, as opposed to 0.323 inch for the pointed ball.  The pointed ball should not be fired in the M1888 rifle.  These cartridges are not believed to be sued in significant quantities.

The Chinese Nationalists and, in turn, the Chinese Communists continued the manufacture of ammunition types originally produced in China under the Japanese, and apparently also retained the Japanese color marking system for identification.  The Japanese color code for small arms ammunition is as follows:

Ball --- Pink/Salmon
Tracer --- Green
Armor-Piercing --- Black
Incendiary --- Magenta
High-Explosive --- Purple
Blanks --- Wooden or Paper bullets


Chinese Communist small arms ammunition packaging is notable only for its lack of uniformity.  Wooden packing boxes may vary widely in size, zinc or galvanized steel containers may or may not be used; inside the package, the rounds may be in cardboard containers of varying size, or may be loose, with or without clips or feed strips.

Packaging type and quality apparently depend on what happens to be available at the arsenal of manufacture.  In general, the packaging is of poor quality by United States standards, and it did not stand up well through the Korean War.  Water-soaked and corroded cartridges in unbroken Chinese packaging were commonplace in Korea.  An attempt was frequently made to waterproof boxes by the caulking of joints and tops but, because of an apparent lack of definite system or standards, the results were poor.

The Chinese Communists repacked significant quantities of captured ammunition, such as United States .30 cal.  No attempt was made to repack the United States cartridges by type or by headstamp.  A repacked box might, for example, contain a mixture of .30 cal ball, AP, and tracer cartridges produced at varying dates by different manufacturers.  Some of the rounds in the same box might even show signs of having been reloaded by the Chinese.
 

The markings on small arms ammunition boxes vary greatly.  Arabic or Chinese numerals, English or Chinese words, may be used.  One box may show extensive information about the contents; the next may show very little.  Markings often differ widely even between boxes containing the same caliber and type of ammunition.  The illustration below portrays only one of the many markings methods that are found.  The most consistently used symbols are those identifying the box contents by caliber and type number.





6.5mm Ball Cartridge, Type 38
 

This cartridge of Japanese design was continued in manufacture by the Chinese after World War II.  It is used in the Type 38 rifle, the Type 44 carbine, and the machineguns Type 3, Type 11, Type 91, and Type 96.  Ball cartridges usually have a red annulus at the junction of the bullet and cartridge case.  Chinese headstamps usually indicate the arsenal mark, the year and the month of manufacture, and occasionally the caliber.


Characteristics

Caliber: 6.5mm (.256 cal)
Weight of cartridge: 20.97g (323.61 gr)
Weight of case: 9.92g (153.09 gr)
Weight of bullet: 8.79g (135.65 gr)
Weight of propellant: 2.15g (33.18 gr)
Length of cartridge: 75.4mm (2.97 in)
Lenght of case: 50.5mm (1.99 in)
Lenght of bullet: 32.5mm (1.28 in)


Packaging
 
    
This ammunition is packed in 500-round and 600-round quantities.  For the 500-round package, one hundred 5-round clips of ammunition are packed loosely in a sealed galvanized metal container, which in turn is placed in a wooden box.  For the 600-round package, there are 15 rounds to a cardboard carton, 14 cartons to a sealed metal container, and one such container to a wooden box.  The markings on the wooden boxes may vary greatly in both in location and in the individual symbols used; however, unchanging symbols either for the caliber or the type of round normally appear somewhere on the box, and will serve to identify its contents.  These constant symbols are shown above, with other characteristics of the packaging.




7.62mm Ball Pistol Cartridge, Type (50?)


This cartridge is interchangeable with the Soviet 7.62mm Type P pistol cartridge, the Czech 7.62mm pistol cartridge, and the 7.63mm Mauser automatic pistol cartridge.  Chinese Communist forces use these cartridges in their Type 50 submachinegun and Type 51 automatic pistol, which are copies of the Soviet PPSh-41 submachine gun and TT1933 automatic pistol.  All of these cartridges are also used in the original Soviet weapons and in the Soviet PPS-43 submachineguns.  Cases are brass with a Berdan primer.  Base markings indicate manufacturing arsenal, lot number, and date of manufacture.


Characteristics

Caliber: 7.62mm (.30 cal)
Weight of cartridge: 10.68g (165 gr)
Weight of case: 4.5g (70 gr)
Weight of bullet: 5.5g (86 gr)
Weight of propellant: 0.58g (9 gr)
Length of cartridge: 34mm (1.36 in)
Lenght of case: 24mm (0.97 in)
Lenght of bullet: 14mm (0.55 in)


Packaging

No Markings Available

Information on packaging of this round is not available.





7.7mm Semi-Rimmed Ball Cartridge, Type 92


Manufacture of this Japanese-designed cartridge was continued by the Chinese after World War II.  It is used in the Type 92 heavy machinegun.  The ball cartridge usually has a red annulus at the junction of the bullet and cartridge case.  Base markings usually give year and month of manufacture, manufacturer's symbol or number, and sometimes caliber.


Characteristics

Caliber: 7.7mm (.303 cal)
Weight of cartridge: 27.78g (428.75 gr)
Weight of case: 11.34g (175 gr)
Weight of bullet: 13.32g (205.63 gr)
Weight of propellant: 2.86g (44.18 gr)
Length of cartridge: 79.5mm (3.13 in)
Length of case: 57.6mm (2.27 in)
Length of bullet: 35mm (1.39 in)


Packaging


Three different methods of packaging this cartridge have been encountered.  It has been found in a 560-round wooden box, details on the interior packing of which are lacking.  There is also a 600-round wooden box which holds 20 cardboard containers, each enclosing 1 Hotchkiss-type machinegun clip of 30 rounds.  Thirdly, a 1,380-round wooden box contains 92 cardboard packets, each holding three 5-round clips.  Although there is considerable variation in the marking of these boxes, consistent use is made of a symbol broadly identifying the contents by type.  This constant marking, which is shown above, is ordinarily found among other groups of characters, and is apparently placed on the box in whatever location suits the marker.



7.7mm Rimless Ball Cartridge, Type 99


This cartridge is used in Japanese 7.7mm Type 99 rifle and in the Japanese Type 92, Type 99, and Type 1 machineguns.  The cartridge is of Japanese design, but the Chinese are believed to have continued its manufacture after World War II.  The Japanese color marking for the round is a red-colored annulus at the junction of the bullet and the cartridge case.  These cartridges may be found in 5-round clips, or in 30-round feed strips for machineguns.


Characteristics

Caliber: 7.7mm (.303 cal)
Weight of cartridge: 26.93g (415.63 gr)
Weight of case: 11.9g (183.75 gr)
Weight of bullet: 12.47g (192.5 gr)
Weight of propellant: 2.67g (41.13 gr)
Length of cartridge: 79.5mm (3.13 in)
Length of case: 57.6mm (2.27 in)
Length of bullet: 31.2mm (1.23 in)


Packaging


Examination of various types of Communist Chinese packaging has disclosed inconsistent location of markings and considerable variation of identifying symbols even on similar boxes for the same item.  As a rule, however, constant symbols affording general identification of the contents by caliber and type appear on small arms ammunition boxes.  The symbol shown above is thought to be the constant symbol that would normally appear on packaging for this round.




7.92mm Ball Cartridge, Type ?


This cartridge still is manufactured by the Chinese Nationalists, as well as by the Chinese Communists.  It can be fired from any weapon chambered for 7.92mm x 57mm rimless ammunition, and is used by the Chinese Communists in a motley assortment of foreign-designed rifles and machineguns.

During World War II, the cartridge was manufactured in large quantities by the United States.  The United States-made rounds are distinguished by the character below on the base, and by having Boxer-type primers rather than Berdan type used in cartridges of Chinese, Japanese, and European manufacture.

 
A reduced-charge version of the round also was made; it was intended for some early Chinese copies of the Czech ZB 26 light machinegun which were constructed of inferior metal.

To date, all cartridges cases found for this round have been of brass.  Cartridge case base markings are stamped, and usually consist of a symbol for the manufacturing arsenal, a date (month and year) of manufacture, and occasionally the Arabic numerals "79," indicating the caliber.  Because of the many manufacturers of the ammunition, a correspondingly wide variation in headstamps may be encountered.


Characteristics

Caliber: 7.92mm (.311 cal)
Weight of cartridge: 25.5g (394 gr)
Weight of case: 12g (185 gr)
Weight of bullet: 10.5g (162 gr)
Weight of propellant: 3g (47 gr)
Length of cartridge: 80mm (3.14 in)
Length of case: 57mm (2.24 in)
Length of bullet: 29mm (1.16 in)


Packaging


This ammunition has been found in three kinds of packaging.  A 500-round wooden box holds one sealed, galvanized metal container, within which are 10 layers of cartridges loaded in 5-round clips; each layer is seperated from the next by a cardboard sheet, and comprises ten 5-round clips.  A 560-round wooden box contains 28 cardboard boxes, each holding 20 rounds individually seperated by a cardboard divider.  Finally, a 1,000-round wooden box encloses a sealed, galvanized metal container in which the cartridges are packed loosely.  The markings on the three types of packaging differ greatly from box to box, bu the symbols shown above appear among the markings quite consistently and may serve to identify the box contents broadly as 7.92mm ammunition.


Next Time: Communist Chinese Mortar Ammunition

Monday 4 January 2016

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