British Explosive Ordnance - Anti-Submarine and Buoyancy Bombs, and Aircraft Depth Charges

British Explosive Ordnance

 Semi-Armor Piercing and Armor Piercing Bombs Introduction

AS bombs, ranging from 100 to 600 pounds, are at present in service use.  They are thin-walled bombs, having a high charge/weight ratio for maximum blast effect on, or under, water.  Aircraft depth charges are used by the British as alternatives for these bombs.

Earlier marks of the 100, 250, and 500 pound bombs employed a Nose Fuze No.32, but later marks incorporate a pistol/detonator combination at the tail only.  The 600 pound bomb uses a tail fuze.

These bombs are painted green overall, and may be filled with Torpex, TNT, or Minol.  Their charge/weight ratio is from 50 to 80 percent, depending on the individual bomb and the filling.  The 100, 250, and 500 pound bombs are streamlined in shape.

AS 100lb Mks I-IV (Obsolescent), and Mk VI (Service)

  

Overall length: 42 inches (Mk VI is several inches longer with nose attachment)

Body length:
-Mks I-III: 31 inches
-Mks IV-VI: 24.08 inches

Body diameter: 8.05 inches
 Wall thickness: 0.11 inches

Tail length: 18 inches
Tail width: 8 inches

Total weight: 98 pounds
Charge/Weight ratio: 45% (approx.)

Fuzing:
-Mks I-III: Nose Fuze No.32
-Mk IV: Tail Pistols No.28 or No.30
-Mk VI: Tail Pistol No.30, or Tail Fuzes No.875 or No.895

Tail No:
-Mks IV: No.7 Mk I
-Mk VI: No.56 Mk I

Color and markings:  Dark green overall
1/2 inch red band 1 inches from nose,
1 inch light green band 4 inches from nose.

  

Body Construction: The Mk IV body consists of a hollow nose forging or casting, and a cast or forged tail adapter, welded to a sheet steel casing.  The hollow nose is threaded to take a solid, flat nose plug, which is secured by a locking screw.  The casing is made of two parts, welded together longitudinally.  The tail adapter receives the exploder container, which is locked and sealed in position, and houses the detonator holder and pistol.

The Mk III body has a nose fitted with a nose fuze adapter, three internal strengthening rings, and a tail adapter.  A ballistic cap screws onto the nose to prevent ricochet.

In the Mk VI body, the nose plug and a cup-shaped nose attachment are welded on.


Tail Construction: The Bomb Mk IV uses a Tail Assembly No.7 Mk I which consists of a sheet-metal tail cone with a cylindrical strut attached by four fins.  It is secured to the tail adapter by four spring clips on the cone.  The tail assembly also has a reach rod, with arming vanes on the after end, which extends through the tail cone to engage the arming fork of the tail pistol.

The tail of the Bomb Mk III consists of a cylindrical strut, attached by fins to a dome, which is secured to the bomb by a central bolt.

The Bomb Mk VI uses a Tail No.58 Mk I, which is secured by four locking screws threaded through four cone-securing bosses welded on at an angle to tail cone.  The screws thread inward and aft to engage slots in the bomb body.


Suspension: The bomb is horizontally suspended by a single lug, which is secured by screws projecting through the case and into a steel-block support pad welded to the interior of the body.
  

Explosive Components:
Exploders: CE

Filling:
-Mk IV: 45lb RDX/TNT 60/40 or 44lb TNT
-Mk VI: 49lb Torpex (when filled with Torpex, a topping of TNT is added at the nose and base)

Remarks: The Tail Pistol No.30 with needle striker is to be used in the Bomb Mk IV for AS bombing.  The Pistol No.28 can be used in place of the No.30 for land bombardment.

The Bomb Mk V was never produced.

AS 250lb Mks I, II, and III (Obsolescent) and Mk IV (Service)
   

Overall length:
-Mk III: 69 inches
-Mk IV: 58 inches

Body length:
-Mk III: 42 inches
-Mk IV: 35.2 inches

Body diameter:
-Mk III: 11.2 inches
-Mk IV: 11.85 inches
  

Wall thickness:
-Mks I and II: 0.125 inches
-Mks III and IV: 0.14 inches

Tail length: Mk IV - 23.4 inches
Tail width: 11 inches

Total weight: Mk IV - 243 pounds
Charge/Weight ratio: Mk IV - 55%

Fuzing:
-Mks I-III: Nose Fuze No.32
-Mk IV: Tail Pistols No.28 or No.30

Tail No: Mk IV - No.8 Mk I

Color and markings:  Dark green overall
1/2 inch red band 1 inches from nose,
1 inch light green band 4 and 1/2 inches from nose.

  

Body Construction: The Mk IV body consists of a hollow nose forging or casting and a cast or forged tail adapter, welded to a sheet-steel casing.  The hollow, flat nose is threaded to take a solid nose plug which is secured by a locking screw.  The casing is made of two parts, welded together longitudinally.  The tail adapter receives the exploder container, which is locked and sealed in position, and houses the detonator holder and pistol.

The Mk I-III bodies have the nose fitted with an adapter for a nose fuze.  Internal strengthening bands are welded to the body, which has no tail adapter.  A ballistic cap screws on the nose to prevent ricochet.


Tail Construction: In the Bomb Mk IV, the tail assembly consists of a sheet-metal cone with a cylindrical strut attached to it by four fins.  The assembly is secured to the tail adapter by four spring clips on the cone.  A reacdh rod, with arming vanes attached to after end, extends through the cone and engages the arming fork of the tail pistol.

The tails of the Bomb Mk I-III consist of a cylindrical strut attached by four fins to a dome-shaped tail cone, and secured to the bomb by a central bolt.


Suspension: The bomb is horizontally suspended by a single lug, secured by screws projecting through the case and into a steel-block support pad welded to the interior of the body.
  

Explosive Components:
Exploders: CE pellets. (Early marks had CE and TNT)

Filling:
-Mks III: 149lb Baratol or 140lb TNT
-Mk IV: 134lb RDX/TNT or 132lb TNT (when RDX/TNT is used, bomb has 1/2-inch nose topping and 1-inch base topping of TNT)


Remarks: These bombs are designed to give maximum blast effect for use against submarines.  The Tail Pistol No.30 with a needle striker is to be used in the Bombs Mk IV for A/S bombing.  The Pistol No.28 can be used in place of the No.30 for land bombardment.

AS 500lb Mks I-IV (Obsolescent)
   

Overall length:
-Mks I and II: 74 inches
-Mk III: 76 inches
-Mk IV: 72.5 inches

Body length:
-Mks I, II, and III: 53 inches

 -Mk IV: 50 inches

Body diameter:
-Mks I and II: 14 inches

 -Mks III and IV: 14.8 inches

 Wall thickness:
-Mks I and II: 0.16 inches

 -Mk III and IV: 0.18 inches

 Tail length: Mk IV - 24.2 inches
 Tail width: Mk IV - 14 inches

Total weight: Mk IV - 490 pounds

Charge/Weight ratio: 62-64%
 Mk IV: 58%

Fuzing:
-Mks I-III: Nose Fuze No.32
-Mk IV: Tail Pistol No.28 or No.30

Tail No: Mk IV - No.9 Mk I

Color and markings:  Dark green overall,
1/2 inch red band 1 inch from nose,
1-inch light green band 6 inches from nose.

  

Body Construction: The Mk IV body consists of a hollow nose forging or casting and a cast or forged tail adapter, welded to a sheet-steel casing.  The nose is threaded to take a solid nose plug, which is secured by a locking screw.  The casing is made of two parts, welded together longitudinally.  The tail adapter receives the exploder container, which is locked and sealed in position, and houses the detonator holder and pistol.

The Mk I-III bodies have the nose of the bomb fitted with an adapter for a nose fuze.  Internal strengthening bands are welded to the body, which has no tail adapter.  A ballistic cap screws on the nose to prevent ricochet.


Tail Construction: The Tail Assembly No. 9 Mk I consists of a sheet-metal cone with a cylindrical strut attached to it by four fins.  The assembly is secured to the tail adapter by four spring clips on the cone.  A reach rod, with arming vanes attached to the after end, extends through the cone and egages the arming for of the tail pistol.

The tails of the Bombs Mks I-III consists of a cylindrical strut attached by four fins to a dome-shaped tail cone, and secured to the body by a central bolt.


Suspension: The bomb is horizontally suspended by a single lug, secured by screws projecting through the case and into a steel-block support pad welded to the interior of the body.
  

Explosive Components:
Exploders: CE pellets. (Earlier bombs had CE and TNT)

Filling:
-Mks III: 291lb TNT or 308lb Baratol
-Mk IV: 282lb TNT or may be filled with RDX/TNT (when RDX/TNT is used, bomb has 1/2-inch nose topping and 1-inch base topping of TNT.


Remarks: These bombs are designed to give maximum blast effect for use against submarines.  The Tail Pistol No.30 with a needle striker is to be used in the Bombs Mk IV for A/S bombing.  The Pistol No.28 can be used in place of the No.30 for land bombardment.

AS 600lb Mk I (Service)

Overall length: 56.7 inches
Body length: 36 inches (w/o nose attachment)
Body diameter: 17.5 inches

 Wall thickness: 0.125 inches

  Tail length: 20.5 inches

 Tail width: 17.5 inches

Total weight: 550 pounds
 Charge/Weight ratio: 80% (approx.)

Fuzing: Tail Fuze No.862

Tail No: No.36 Mk I

Color and markings:  Dark green overall,
1/2 inch red band and 1-inch light green band around body.

  

Body Construction: The body consists of three pieces welded together; a concave nose, parallel sides, and a tapered base to receive the clip-on tail.  The after end is closed off by the closing plate, which houses the exploder container.  A round nose cap, attached to the nose for streamlining during air travel, breaks off on impact, giving the bomb an unstable trajectory, and so preventing ricochet.


Tail Construction: The clip-on type tail consists of a cylindrical strut secured to the tail cone by four fins.  The tail cone is constructed of four pieces and is held together by three rivets only.  There is no reach rod extending through the tail cone, as the fuze is not the arming-vane type.  The tail breaks off on impact with water, contributing to the unstable trajectory of the bomb.


Suspension: The bomb may be suspended from British planes by the single lug, or from US aircraft by the dual lugs on either side of the single lug.  when either dual lugs or the single lug are used, the remaining lug screw holes are closed by transit screws.
  

Explosive Components:
Exploders: CE

Filling: 432lb of Minol II or 439lb Torpex. (1/2-inch layer of TNT at base when filled with Minol or Torpex)


Remarks: The fuze is fitted in an anticounter-mining chamber.





  

Aircraft Depth Charges Introduction


The depth charges included in this section are those dropped from aircraft in antisubmarine warfare.  Only one size, the 250-pound is currently in use.  They are normally carried on a bomb carrier.

These bombs consist of a cylindrical metal case, with an explosive charge, and have a central tube in which are house a primer, a detonator, and a tail pistol when the depth charge is ready for use.  The depth at which the depth charge will detonate is determined by the pistol, which operates by hydrostatic pressure.  A safety device is incorporated to render the depth charge safe in the event of the carrying aircraft's sinking after a forced landing.  This safety device, however, does not always prevent detonation if the depth charge is dropped safe, as it may be affected by impact with the water.

Aircraft depth charges are thin-walled, with a loading factor of about 65 percent.  They are painted dark green overall, with a red band, painted dark green overall, with a  red band, and a colored band to indicate the nature of the explosive filling.  Attachments, comprising a nose fairing and/or a tail, are usually fitted to a depth charge to reduce the air resistance when carried externally on an aircraft, and to increase stability of the air trajectory.  Unless fitted with a parachute, failure to detonate may result if the depth charge is dropped from too great a height or at too great a speed.

DC 250lb Mk VIII (Obsolescent)

Overall length: 56 inches

Body length: 38.15 inches

Body diameter: 11 inches
 Tail length: 18 inches

Tail width: 11 inches

Total weight: 250 pounds
Charge/Weight ratio: 64%

Fuzing: Hydrostatic Tail Pistols Mks XIV, XIV*, XVI, XVI*, or Mk X**

Tail No: No.78 Mk I
  

Color and markings: Dark green overall,
1/2-inch red band near nose,
2-inch light green cross-hatched band near suspension lug.

Body Construction: The body consists of a welded cylindrical outer case to which a convex nose is welded.  The bomb is sometimes fitted with a concave nose attachment.  The rear end of the body is closed by an end cover dished inwards, which houses two filling holes that are closed by bungs.  On the cover are six equi-spaced lugs for attaching the tail.  A primer tube fits into the rear cover and extends approximately half the length of the body.  It has a 3.5-inch internal diameter, and contains the primer, pistol, and depth adjuster.


Tail Construction: The tail is an open-ended, cylindrical, sheet-metal tail supported internally by a spiral wire stiffener.  A strengthening band on the forward end carries six brackets, which are attached by studs and nuts to the six lugs on the closing cover of the depth charge.  Three equally spaced ports are provided in the tail, through one of which is passed the fuze-setting control link when the depth charge is loaded on the aircraft.  The tail breaks off on impact with the water.
 
Suspension: The bomb employs horizontal suspension by a lug welded to the body at the center of gravity.  It may be fitted with two additional lugs for suspension from US aircraft bomb racks.
  

Explosive Components:
Filling: 160lb Amatol


Remarks: This depth charge is dropped from a maximum height of 500 feet and at a maximum speed of 173 mph.

DC 250lb Mk XI and XI* (Service)

Overall length: 54.8 inches

Body length: 37 inches

Body diameter: 11 inches
 Tail length: 17.8 inches

Tail width: 11 inches

Total weight: 265 pounds
Charge/Weight ratio: 66%

Fuzing: Hydrostatic Tail Pistols Mks XIV, XVI, XIX, or Mk XX

Tail No: Mk III (Mk IV when using Pistols Mk XIX or XX)
  

Color and markings: Dark green overall,
1/2-inch red band near nose,
colored band indicating nature of explosive painted around body in front of suspension lug.

Body Construction: The body is a welded cylindrical case closed at each end by a cover which is welded on.  The central primer tube is welded into an opening in the rear cover, and extends approximately half way through the body.  Equi-spaced around the rear cover are three lugs, each drilled and tapped to receive a stud used for securing the tail to the depth charge.  Two filling holes, each closed by a bung, are provided in the rear cover.  The front cover is dished inwards to prevent ricochet.


Tail Construction: The Tail Assembly Mk III is simply a cylindrical drum open at both ends.  A strengthening ring is welded to the front end and provided with three equi-spaced brackets, weakly riveted on, which fit over the studs in the corresponding lugs on the rear end cover of the body.  The tail is strengthened by six circumferential corrugations.  The tail breaks off on impact with water.  The front of the tail has one large port for the fuze-setting control link, and two small ports to give access to pistol and valve unit when fitting the fuze-setting control link.

The Tail Mk IV is designed with arming vanes and a reach rod to arm Pistols Mks XIX and XX, which are of the air-arming type and are replacing the Tail Hydrostatic Pistols Mks XIV and XVI.  This tail is constructed with a three-segment cone, to which are riveted three fins supporting the three-segment cylindrical strut.  Three hand clearance holes are equi-spaced around the forward end of the cone.
 
Suspension: The Bomb Mk XI has a single lug welded to the case at the center of gravity for British aircraft.  The Bomb Mk XI* has dual lugs welded to its case for suspension from US aircraft.
  

Explosive Components:
Filling: 175lb Torpex






Buoyancy Bombs Introduction

Only the 250lb buoyancy bomb has been used by the British.  The bomb is designed to be dropped in front of ships under way, and to rise and detonate on contact with the ship's bottom.

The bomb consists primarily of an explosive charge, a buoyancy chamber, and a clip-on tail.  it is fuzed with a  Tail Fuze No.850.  The bomb in painted dark gray overall, and has a red nose band and a green band at the base of the ogive.





B 250lb Mk IV (Service)

Overall length: 72 inches

Body length: 42 inches

Body diameter: 14.3 inches
 Tail length: 28 inches

Tail width: 14.3 inches

Total weight: 250 pounds (approx.)
Charge/Weight ratio: 40% (approx.)

Fuzing: Tail Fuze No.850

Tail No: No.23 Mk I with the Mk III body.
  

Color and markings: Dark grey overall,
1/2-inch red band 3 inches from nose,
1/2-inch green band 9 and 1/2 inches from nose.

Body Construction: The bomb consists of a truncated, cone-shaped charge case with a  concave nose welded on, a buoyancy chamber secured to the charge case by twelve nuts, and a clip-on tail.  A convex nose attachment can be fitted to the nose by means of three brackets, equi-spaced around the edge of the nose.  The buoyancy chamber has twelve hand clearance pockets around the forward end to permit access to the twelve bolts securing the charge case.  Internal reinforcements are spot welded to the interior forward half of the buoyancy chamber, and two circular stiffeners extend athwartships through the chamber, spot welded to the chamber wall.  An exploder tube extends centrally through the buoyancy chamber and charge case.  It is welded at the rear to the joint ring fitting inside the fuze pocket, and supported by the stiffening ring in the middle of the buoyancy chamber.


Tail Construction: The Tail No.23 Mk I, used on the Mk III body, consists of a tail cone with cylindrical strut secured by four fins riveted to the and tack welded to the tail cone.  The tail assembly is attached to the body by spring clips, and breaks free on water impact.

Functioning: On striking the water, the nose attachment is dished in and the tail breaks away.  When the tail breaks away, it uncovers a wheel-shaped disc on the base of the bomb.  This is the contact disc, to which are attached three chains, the opposite ends being fastened to the support ring on the bomb base.  If these chains are tight, the fuze is armed as the contact disc rises during the arming process.  If the bomb fails to hit a ship upon rising, it sinks after a short flotation period.
 
Suspension: The bomb is suspended by a single lug secured by four screws threaded into a suspension-lug stiffener, and a boss, spot welded to the interior of the buoyancy chamber.
  

Explosive Components:
Exploders: CE exploders in central tube

Filling: 113.2lb Torpex 2, with 3.25lb TNT topping in after end of charge case.


Remarks: This bomb is designed to be dropped in front of ships under way, and to rise and detonate on contact with the ship's bottom.  The concave nose portion of this bomb is designed to give better underwater ballistics, rather than a Munroe effect.

Next Time: Incendiary, Smoke, and Light-Case (Chemical) Bombs

British Explosive Ordnance - Semi-Armor Piercing, Armor Piercing, and Deep Penetration Bombs

British Explosive Ordnance

 Semi-Armor Piercing and Armor Piercing Bombs Introduction



There are two British SAP bombs in present service use.  They are designed for penetration of resistant targets, such as reinforced concrete or medium armored targets, where penetration is required before the bomb detonates.

Only one AP bomb, the 2000lb, is used by the British.  It is used for attacks against heavily armored targets, such as capital ships, and is so constructed and fuzed that the bomb does not break up on impact.  Detonation does not occur until after the target is penetrated.  A 450lb AP bomb was used early in the war, constructed along the same lines as the 2000lb, but it is now obsolete.

Both the AP and SAP bombs are fuzed in the tail only.  Earlier marks were designed to receive a tail fuze, but later marks are fitted for pistol/detonator combination.  In later marks, the pistol used for fuzing is supplied in position in the bomb, without detonators, where it acts as a tail transit plug.

SAP bombs are dark green overall, with a white band on the nose just before a red band.  The actual construction is similar to the GP bombs, but the case is thicker, and they are even more streamlined.  They are normally filled with TNT, and have a loading factor of about 20 percent.  Mks I, II, III, and IV have tails secured by a fuze locking ring which is threaded left-handed, while the Mk V has a clip-on tail.

AP bombs are dark green in color.  The nose is painted light green to the point of widest diameter.  Two white bands, separated by a red band, are painted around the nose.  The bombs are of one-piece construction, and are filled with shellite, which consists mainly of picric acid and is very insensitive.  The loading factor is about 10 percent.

SAP 250lb Mks II and III (Obsolete), and Mks IIC, IIIC, and V (Service)

Overall length: 49 inches

Body length: 31.5 inches

Body diameter: 9.2 inches

Wall thickness: 0.91 to 0.99 inches at maximum  diameter and 0.61 to 0.69 inches at minimum thickness beginning 16.8 inches abaft nose.

Tail length: No.10 Mk I and No.5 Mk I - 18 inches
Tail width: 9.2 inches

Total weight: 245 pounds
Charge/Weight ratio: 17%

Fuzing:
-Mks II-IV: Tail Fuze No.30
-Mk V: Tail Pistols No.28 or No.30

Tail No:
-Mks II and III: No.1 Mk I
-Mk V: No.10 Mk I

Color and markings:  Dark green overall
1/2 inch white band 3 inches from nose,
1/2 inch red band 3 and 1/2 inches from nose,
1 inch light green band 6.5 inches from nose.

  

Body Construction: The Mk V body is forged steel with a pointed nose and an open base threaded internally to receive the exploder container, which is cemented in position.  The base of the body is threaded externally to receive a tail adapter, which is in the form of a coned ring with four equi-spaced slots to receive the spring clips of the tail.  Earlier marks were similar to the Mk V, with slight variations in the tail adapter.


Tail Construction: The Tail No.10 Mk I has a tail cone with a cylindrical strut attached by four fins.  It is attached to the bomb body by four spring clips.  The arming spindle engages the fork in the tail pistol.  The Tail No.1 Mk I, used on Bombs Mk II and III has no spring clips, while the Tail No.3 Mk I used on Bombs Mk IIC, Mk IIIC, does have spring clips.


Suspension: A single suspension lug is secured to the body by four screws.
  

Explosive Components:
Exploders: CE pellets in Mks II-IV, and HE in the Mk V.

Filling:
-Mk V: 40.5 pounds TNT/Beeswax
-Mks II-IV: 41.5 pounds TNT


Remarks: The Tail Fuze No.30 has left-hand threads on the securing ring.  Use of the Tail Pistol No.37 is unlikely. 

Tail fins are usually painted red when the Time Pistol No.37 is used.

Any mark may be found fitted with a copper driving band for proof firing from the BL 9.2 inch Howitzer.

SAP 500lb Mks II-III (Obsolete), and Mks IIC, IIIC, and V (Service)
   

Overall length: 62 inches

Body length: 41.8 inches

Body diameter: 11.5 inches

Wall thickness: 1.22 to 1.32 inches at maximum  diameter and 0.82 to 0.92 inches at minimum thickness beginning 23 inches abaft nose.

Tail length:
-No.6 Mks I: 21 inches
-No.11 Mk I: 20.4 inches
-No.27 Mk I and II: 9.24 inches

Tail width: 11.5 inches

Total weight: 490 pounds
Charge/Weight ratio: 18%

Fuzing:
-Mks II-IV: Tail Fuze No.30
-Mk V: Tail Pistols No.28 or No.30

Tail No:
-Mks II and III: No.1 Mk I
-Mks IIC and IIIC: No.4 Mk I
-Mk V: No.11 Mk I, or No.27 Mk I

Color and markings:  Dark green overall
1/2 inch white band 3 inches from nose,
1/2 inch red band 8 and 1/2 inches from nose,
1 inch light green band 8 inches from nose.

  

Body Construction: The Mk V body is forged steel with a pointed nose and an open base, threaded internally to receive the exploder container, which is cemented in position.  The base of the body is threaded externally to receive the tail adapter, which is in the form of a coned ring with four equi-spaced slots to receive the spring clips of the tail.  Earlier marks were similar to the Mk V, with slight variations in the tail adapter.


Tail Construction: The Tails No.27 Mks I and II are the short-type tail unit with arming vanes protruding beyond the strut and fins.  The Tail Assembly No.11 Mk I consists of a tail cone with a cylindrical strut attached by means of four fins.  It is attached to the bomb body by four spring clips.  The arming spindle engages the fork in the tail pistol.  The Tail No.1 Mk I used on Bombs Mk II and Mk III has no spring clips, while the No.4 Mk I tail used on Bombs Mk IIC and Mk IIIC does have spring clips.


Suspension: A single suspension lug is secured to the body by four screws.
  

Explosive Components:
Exploders: CE and TNT in Mks II-IV; CE only in Mk V.  There is no separate layer of TNT around the exploder as in the 250lb SAP Mk V.

Filling:
-Mks II-IV: 90 pounds TNT
-Mk V: 89 pounds TNT


Remarks: The Tail Fuze No.30 has left-hand threads on the securing ring.

Use of the Tail Pistol No.37 is unlikely, but if used, tail fins are usually painted red.

The Bomb Mk I is very old and will not be found.  The Mk IV bomb was manufactured, but never filled.

AP 2000lb Mks I, II, III, and IV (Service)
   

Overall length: 113 inches

Body length: 80 inches

Body diameter: 13.5 inches
 Wall thickness: 2.4 inches (approx.)

 Tail length: 35.5 inches
 Tail width: 13.5 inches

Total weight: 1934 pounds
Charge/Weight ratio: 9%

Fuzing:
-Mks I, II, and III: Tail Fuze No.37
-Mk IV: Tail Pistol No.30

Tail No:
-Mk I: No.1 Mk I
-Mks II and III: No.10 Mk I
-Mk IV: No.47 Mk I

Color and markings:  Dark green overall, with light green nose
Three 1/2 inch bands, white, red, and white respectively, painted 4 inches to 5 and 1/2 inches from tip of nose.

  

Body Construction: The Bomb Mk I has a forged steel body with a solid nose approximately 1.9 feet long and a slight taper from the maximum diameter to the tail.  The base is threaded externally to take a tail adapter, and internally to take a base adapter, which receives the exploder container.  The fuze is locked in position by a fuze securing ring.  The Mks II and III are similar to the Mk I, except for the tail adapter, which has four equi-spaced holes threaded for attachment of the tail.  The Mk IV is modified to take a Tail Pistol No.30.


Tail Construction: The Tail No. 1 Mk I is of aluminum alloy, consisting of a cylindrical strut attached to the tail cone by four vanes.  It fits over the tail adapter and is secured by six screws.  The Tail No.15 Mk I is similar to the No.1 Mk I, but is made of steel.  It has a strengthening ring two inches from the base, and is secured to the tail adapter by four wing bolts.  The Tail No.47 Mk I consist of a cylindrical strut secured to the tail cone by four fins which are riveted on.  A reach rod extends through the tail cone, and is supported by a spider.


Suspension: The bomb is suspended from the plane by two suspension bands.
  

Explosive Components:
Exploders: CE issued in position in exploder container.
Filling: 166 Shellite, with a composition pad in the forward end of the cavity, sealed aft with washers and cement.  Shellite is a very insensitive explosive consisting of 70% picric acid and 30% dinitrophenol.




Deep Penetration Bombs Introduction

These bombs were designed for special operational uses to give deep penetration of the earth and to produce heavy shock waves as a result of the explosion of their main charge.  They have a charge/weight ratio of about 45%, and are not intended for use as armor- or concrete-piercing bombs.

The two sizes of bombs are identical in all respects, the 22000 pound DP being merely an enlarged version of the 12000 pound DP.  A rather unusual feature of these bombs is the use of a cowl between the bomb body and the tail assembly to enhance their streamlining.  Both DP bombs are tail fuzed only, each bomb using three Tail Pistols No.58 located 120 degrees apart in the base plate.

These bombs have been adapted by the US for service use after slight modifications in the method of construction.

DP 12,000lb Mk I "Tallboy" (Service)

Overall length: 21 feet

Body length: 10 feet, 4 inches

Body diameter: 3 feet, 2 inches

Wall thickness:
-Near tail: 1.25 inches
-Near nose: 4.1 inches

Tail length: 10 feet, 8 inches

Tail width: 3 feet, 6 inches (across fins)

Total weight: 11,885 pounds
Charge/Weight ratio: 45% (approx.)

Fuzing: Mk III - Three Tail Pistols No.58 Mk I

Tail No: No.78 Mk I
  

Color and markings: Green overall, Red band near nose

Body Construction: The bomb body is manufactured of cast steel, with a solid nose plug, and with three exploders fitted 120 degrees apart in the base plate.  The bombs are issued with exploders inserted, and the exploder tubes are sealed with shipping plugs.

The tail is attached to the after end of the bomb body by 12 studs.  A cylindrical metal cowling, placed between the bomb body and the tail cone, enhances the streamlining of the bomb.

The bomb body contains an explosive filling of Torpex with a one-inch layer of TNT topping added to the after end.  Four inches of wood-meal/wax composition is then added, and the filling sealed with a 1/2 inch plyboard washer.  The three exploders pass through holes in this washer and are held in place by a heavy base plate, which is secured by bolts to the bomb body.


Tail Construction: The special tail unit, No.78 Mk I, is constructed of light alloy and consists of a cone to which are attached four fins of streamlined cross-section.  The fins are set at an angle of 5 degrees to the axis of the tail cone, giving a slight right-hand spin to the bomb as it falls.  The tail fits over twelve 7/16 inch studs fitted into the bomb body, and is securely fastened to the studs by Simmonds nuts.  Three hand-holes in the tail cone give ready access to the three tail pistols.
 
Suspension: The bomb is suspended in the plane by twin suspension links.  Each link is coupled beneath the bomb by a special Vickers release clip, capable of either electrical or manual operation.

In addition to the suspension links, the bomb is positioned in the plane by a standard crutching system.
  

Explosive Components:
Exploders:
-Primary: 2 ring and 2 solid CE pellets; 4 solid RDX/Beeswax pellets
-Secondary: 2 ring and 2 solid large RDX/Beeswax pellets (placed in a special exploder tube into which the standard exploder container fits)


Main Filling: Approximately 5,200 pounds Torpex surmounted by a 1-inch topping of TNT.


Remarks: This bomb is designed for special operation uses, and its employment will be restricted to certain specified bomb commands.  The initials "DP" signify its deep penetration characteristics, although the bomb is not designed for armor or concrete piercing.  Rather, it is intended to produce heavy shock waves as a result of the explosion of its heavy main charge deep within the earth.

The bomb is carried on specially adapted Lancaster aircraft.  The striking velocity of the bomb, when released at an altitude of 18000 feet, and an air speed of 200 mph, is stated at 1,097 ft/sec at which speed it has developed a rotational velocity of 300 rpm.

The filling and exploder system of this bomb is identical to that of the 22000 pound DP Bomb, "Grand Slam".  The two bombs are identical in all respects, the 22000 pound DP being merely an enlarged version of the 12000 pound DP Bomb.

DP 22,000lb Mk I, "Grand Slam" (Service)

Overall length: 25 feet, 6 inches

Body length: 12 feet, 6 inches

Body diameter: 3 feet, 10 inches

Wall thickness:
-Near tail: 1.75 inches
-Near nose: 7.75 inches

Tail length: 13 feet, 4 inches

Tail width: 4 feet, 4 inches (across fins)

Total weight: 22,400 pounds
Charge/Weight ratio: 42% (approx.)

Fuzing: Mk III - Three Tail Pistols No.58 Mk I

Tail No: No.82 Mk I
  

Color and markings: Green overall, Red band near nose

Body Construction: The bomb body is manufactured of cast steel, with a solid nose plug and with three exploders fitted 120 degrees apart in the base plate.  The bomb bodies are issued with exploders inserted, and the exploder tubes are sealed with shipping plugs.

The tail is attached to the after end of the bomb body by 12 studs.  A cylindrical metal cowling, placed between the bomb body and the tail cone, enhances the streamlining of the bomb.

The bomb contains an explosive filling of Torpex, with a one-inch layer of TNT topping added to the after end.  Four inches of woodmeal/wax composition is then added, and the filling sealed with a 1/2 inch plyboard washer.  The three exploders pass through holes in this washer and are held in place by a heavy base plate, which is secured by bolts to the bomb body.


Tail Construction: The special tail unit, No.82 Mk I, is constructed of light alloy and consists of a cone to which are attached four fins of streamlined cross-section.  The fins are set at an angle of 5 degrees to the axis of the tail cone, giving a right-hand spin to the bomb as it falls.  The tail fits over twelve 7/16 inch studs fitted into the bomb body, and is securely fastened to the studs by Simmonds nuts.  Three hand-holes in the tail cone give ready access to the three tail pistols.
 
Suspension: The bomb is suspended in the plane by twin suspension links.  Each link is coupled beneath the bomb by a special Vickers release clip, capable of either electrical or manual operation.

In addition to the suspension links, the bomb is positioned in the plane by a standard crutching system.
  

Explosive Components:
Exploders:
-Primary: 2 ring and 2 solid CE pellets; 4 solid RDX/Beeswax pellets
-Secondary: 2 ring and 2 solid large RDX/Beeswax pellets (placed in a special exploder tube into which the standard exploder container fits)

Main Filling: Approximately 9,200 pounds Torpex surmounted by a 1-inch topping of TNT.


Remarks: This bomb is designed for special operation uses, and its employment will be restricted to certain specified bomb commands.  The initials "DP" signify its deep penetration characteristics, although the bomb is not designed for armor or concrete piercing.  Rather, it is intended to produce heavy shock waves as a result of the explosion of its heavy main charge deep within the earth.

The bomb is carried on specially adapted Lancaster aircraft.  The striking velocity of the bomb, when released at an altitude of 16000 feet, and an air speed of 200 mph, is stated at 1,097 ft/sec at which speed it has developed a rotational velocity of 60 rpm.

The general arrangement of this bomb is identical to that of the 12000 pound DP Bomb "Tallboy".  The two bombs are identical in all respects, the 22000 DP being merely an enlarged version of the 12000 DP Bomb.

Grand Slam bombs made in the US differ somewhat in body construction from those made in Britain.  The body is built up of five sections welded together.  The solid nose and the base sections are made of forged steel, while the three center sections are made of rolled plate, longitudinally welded, taper-bored internally, and then set in a die to form the external contours.

Next Time:  Anti-Submarine and Buoyancy Bombs, and Aircraft Depth Charges

British Explosive Ordnance - Medium and High Capacity Bombs

British Explosive Ordnance

Medium Capacity Bombs Introduction



These bombs are designed for general operational use as alternatives to the corresponding GO bombs.  They are comparable to the US GP series, with a loading factor of approximately 50%, parallel sides, and ogival noses.

They may be fuzed at the nose and tail, or at the nose or tail only, if so desired.  When shipped, they are plugged at the nose and fitted with a Tail Pistol No.28 or No.30 (without detonators), the pistol acting as a tail transit plug.

These bombs are painted dark green overall, with a red band around the bomb body near the nose denoting that the bomb has been filled, and a light green band around the nose end indicating its HE nature.  The type of filling is stencilled around the bomb body, as is the monogram of the filling station, date of filling, etc.  These bombs are supplied fitted with transit bases, and the larger bombs have transit rings in addition to the bases.

MC 250lb, Mks I and II (Service)

  

Overall length: 55.5 inches

Body length: 27.5 inches

Body diameter: 10 inches

Wall thickness: 0.3 inches
Tail length: 27 inches (approx.)
Tail width: 10 inches

Total weight: 225 pounds (approx)
Charge/Weight ratio: 50% (approx)


Fuzing: Nose Pistol No.27, 42, 44; Tail Pistol No.28, 30, or 37

Tail No: No.2 Mks I or II

Color and markings:  Dark green overall
1/2 inch red band around nose,
1 inch light green band around base of ogive

  

Body Construction: The bomb has a solid drawn or rolled steel body.  The exploder containers screw into the nose and male base plates.  This bomb has parallel sides, with an ogival nose and a slight rear taper, similar to the construction of US General Purpose Bombs.


Tail Construction: The tail consists of a cylindrical tail strut secured to the tail cone by four fins.  The tail assembly is secured to the bomb body by four spring clips, which engage slots in the tail end of the body.  A reach rod through the tail cone, having arming vanes attached to the after end, engages the arming fork in the tail pistol.


Suspension: The Bomb Mk I has a single suspension lug welded to the bomb body.  The Bomb Mk II has dual lugs welded to its case for suspension from US aircraft, in addition to a single lug.

Explosive Components:
Exploders: CE pellets
Filling: Amatol or Pentolite


Remarks: This bomb is supplied with a Tail Pistol No.28 or 30, and may or may not be fuzed in the nose.

The Anti-Disturbance Fuze No.845, formerly incorporated in the nose of bombs fuzed with the Tail Pistol No.37, is obsolete.

Tail fins are usually painted red when a time pistol is used.

MC 500lb Mks I-V (Obsolescent), and Mks VI-XII (Service)
   

Overall length (w/ long tail): 70.6 inches
Overall length (w/ short tail): 57.8 inches

Body length: 41 inches

Body diameter: 12.9 inches

Wall thickness:
Mks I, II, VI, VII: 0.3 inches
Mks III, IV, V, VIIII-XII: 0.42 inches

Tail length:
No.25 Mks I, II: 28 inches
No.28 Mks I, II: 14 inches

Tail width: 12.9 inches

Total weight: 499lb Amatol filled (Mk VIII with short tail)
Charge/Weight ratio: 50%


Fuzing: Nose Pistol No.27, 42, 44; Tail Pistol No.28, 30, or 37

Tail No: No.2 Mk I; No.25 Mks I or II; No.26 Mk I; or No.28 Mk I

Color and markings:  Dark green overall
1/2 inch red band around nose,
1 inch light green band around base of ogive

  

Body Construction: The bomb has parallel sides, with an ogival nose and a slight rear taper, similar in construction to US General Purpose bombs.

With the exceptions as given below, exploder containers screw into the nose and base plate.

Mk I: Fabricated, rolled steel sheet, welded, with nose and tail welded on.

Mk II: Drawn tube, nose formed by "bottling" process, tail welded on.

Mk III: Cast

Mk IV: Cast to 500lb GP dimensions

Mk V: Same as Mk III but center of gravity was off so all were declared obsolescent immediately.  Only used with long tail unit.

Mks VI, VII, VIII, and IX are the same as Mks I, II, III, IV, respectively, with American dual suspension lugs added.

Mk X: Forged body, solid nose, fuzed only in tail.

Mk XI: Mk VII with a solid nose.

Mk XII: Mk VII with improved welds at the after end, and fuzed both nose and tail.


Tail Construction: The Tails No.25 and No.28 are similar in construction, each consisting of a cylindrical strut attached to a tail cone by four fins.  The tail assembly is secured to the body by four spring clips which engage slots in the tail end of the body.  Turnbuckle fittings are provided for two of the springs as a locking device.  A reach rod running through the tail cone engages the arming fork of the pistol, and carries the arming vanes at its after end.  The arming vanes protrude beyond the cylindrical strut and the fins on the short-type Tail Unit No.28.


Suspension: Mks I-V of this bomb have a single suspension lug welded to the body, while Mks VI-XII have dual lugs for suspension from US aircraft welded on in addition to a single lug.
  

Explosive Components:
Exploders: CE pellets
Filling: (Mk VIII) 210lb Amatol 50/50 or 60/40; 226lb Amatex 51/40/9; 222lb RDX/TNT 60/40; or 232lb Torpex 2.


Remarks: These bombs are supplied with a Tail Pistol No.28 or No.30, and may or may not be fuzed at the nose.

The short-type tail unit, such as the No.28 Mk I, is used when the bombs are dropped from fighter-bomber aircraft.

The Anti-Disturbance Fuze No.845, formerly incorporated in the nose of bombs fuzed with the Tail Pistol No.37, is now obsolete.

Tail fins are usually painted red when a time pistol is used.

MC 1000lb Mks I and II (Service)
   

Overall length: 72.5 inches

Body length: 52.5 inches

Body diameter: 17.75 inches
 Wall thickness: 0.48 inches

 Tail length: 20 inches
 Tail width: 17.5 inches

Total weight: 1021lb Amatol filled
Charge/Weight ratio: 47%


Fuzing: Nose Pistol No.27, 42, 44; Tail Pistol No.28, 30, or 37

Tail No: No.38 Mk I

Color and markings:  Dark green overall
Red band around nose,
Light green band around base of ogive

  

Body Construction: The bomb body is a hollow steel casting having parallel sides, an ogival nose, and a slight taper at the after end.  The exploder containers thread into the nose and male base plate.  This bomb is similar in appearance to US General Purpose Bombs.


Tail Construction: The tail assembly consists of a cylindrical strut attached to the tail cone by four sheet-metal fins.  A reach rod with arming vanes on the after end extends through the tail cone and engages an arming fork in the tail pistol.  The tail is secured to the body by four wing bolts and retained in the tail ring by split pins.  The arming vanes protrude beyond the cylindrical strut.


Suspension: The Bomb Mk I has a single suspension lug at the center of gravity attached to two stop plates, and dual "U" bolt suspension lugs, 180 degrees removed from the single lug, for carrying in US bomb racks.  Both sets of lugs are welded onto the body.  The Bomb Mk II has a strengthened form of US lug for dive bombers.
  

Explosive Components:
Exploders: CE pellets
Filling: 475lb Amatol 50/50 or 60/40, or Amatex 9; 500lb of RDX/TNT; or 525lb Torpex 2.


Remarks: This bomb is supplied with a Tail Pistol No.28 or No.30 in position, and may or may not be fuzed in the nose.

The Anti-Disturbance Fuze No.845, formerly incorporated in the nose of bombs fuzed with the Tail Pistol No.37, is now obsolete.

Tail fins are usually painted red when a time pistol is used.

MC 4000lb Mks I and II (Service)
   

Overall length: 109.5 inches

Body length: 74.5 inches

Body diameter: 30 inches
 Wall thickness: 0.75 inches

 Tail length: 33 inches
 Tail width: 30 inches

Total weight: 3764lb Amatol filled
Charge/Weight ratio: 58%


Fuzing: Nose Pistol No.27, 42, 44; Tail Pistol No.28, 30, or 37

Tail No: No.38 Mk I

Color and markings:  Dark green overall
Red band around nose,
Light green band around base of ogive

  

Body Construction: In the Bomb Mk I the exploder containers screw into the nose and make base plate.  The body has parallel sides, an ogival nose, and a slight taper at the body base.  It is similar in appearance to US General Purpose Bombs.  The Bomb Mk II has a strengthened after end due to better welding.


Tail Construction: The bomb employs a short-type tail unit, consisting of cylindrical strut attached to a tail cone by four fins.  A reach rod, having arming vanes at its rear, extends through the tail cone and engages the arming fork of the tail pistol.


Suspension: The bomb has a single lug 44 inches from the nose fuze tip, for regular suspension, and dual lugs 30 inches apart diametrically opposite the single lug for suspension from US aircraft.
  

Explosive Components:
Exploders: CE pellets
Filling: 2166lb Amatol 60/40; 2195lb Amatex 9; or 2265lb RDX/TNT 60/40.


Remarks: The Anti-Disturbance Fuze No.845, formerly incorporated in the nose of bombs fuzed with the Tail Pistol No.37, is now obsolete.

Tail fins are usually painted red when a time pistol is used.

High Capacity Bombs Introduction


These bombs are thin-walled and have a high charge/weight ratio.  They are used for general bombardment purposes on operations where maximum blast damage is required.  At the present time this series includes bombs of 2000, 4000, 8000, and 12000 pounds.

The earlier marks of these bombs are provided with side fuzing positions, which are used for special operations; the bombs normally being fuzed in the nose only.  The later marks of the 2000, and 4000 pound bombs, and all of the 8000 and 12000 pound bombs of the series, have three nose-fuze pockets, all of which generally are used.

Central exploder tubes are at present fitted in all types of HC bombs, and where side fuzing positions or nose fuzing positions offset from the longitudinal axis of the bomb are used, auxiliary exploder tubes connect the fuzing positions to the central tube.
 
These bombs are characterized by dome-shaped noses and parallel sides, and may be fitted with nose attachments to retard the bomb in flight.  Drum-type tails are generally used, although the 2000 pound bomb may be fitted with a parachute attachment, and the 12000 pound bombs sometimes incorporate the normal GP type tail assembly, ie tail cone, cylindrical strut, and four fins.

The body is usually welded together and the tail bolted on.  The 8000 and 12000 pound bombs consist of two and three body sections, respectively, bolted together.

HC bombs are supplied uncrated, and are fitted with transit rings.  All fuzing positions are plugged with transit plugs.  Tails, nose attachments, and parachute attachments are supplied in separate packages.

HC 2,000lb Mks II and III (Service)

Overall length: 131 inches

Body length: 89 inches

Body diameter: 18.5 inches 

Wall thickness: 0.19 inches

Tail length: 40 inches

Tail width: 17.9 inches

Total weight: 1,723 pounds, Amatol-filled
Charge/Weight ratio: 71%

Fuzing: Mk III - Three nose pistols, No.27,42, or 44
Mk II - Three nose fuze cavities present but only the center one can be used, with one of the above fuzes.

Tail No: No.39 Mk I
  

Color and markings:  Dark Green overall
1/2 inch red band 6 inches from front cylindrical shell,
2 inch light green band 16 inches from edge

Body Construction: The body is a steel fabricated cylinder with a dome-shaped nose and parallel sides, and is closed by a flat plate bolted to a flange within the after end.  The base flange is fitted with locating pins for the tail, and the holes to receive the tail securing bolts are drilled through it.

A central tube is cemented to the stem of the central exploder container in the nose, and extends through the body almost to the closing plate.  All three nose fuzing positions house exploder containers, the two side ones extending radially inward toward the central tube.


Tail Construction: The tail is a metal cylinder, having an angle ring secured at each end.  Hand holes in the tail cylinder give access to the tail securing bolts, which thread through tapped bosses on the forward angle ring.  Other holes in the cylinder provide stability in flight.
 
Suspension: The bomb uses a single suspension lug 46 inches from the nose dome secured by eight screws.
  

Explosive Components:
Exploders:  CE exploder in pistol exploder containers, and CE pellets in central tube.

Main Filling: 1230lb Amatol 60/40 or 50/50; 1285lb RDX/TNT 60/40; or 1360lb Torpex 2.


Remarks: The bomb may have a nose attachment consisting of a light-gauge metal cylinder extending from the body shell forward around the dome-shaped nose, to retard it in flight.

HC 4,000lb Mk I (Obsolescent)

Overall length: 115 inches

Body length: 88.5 inches

Body diameter: 30 inches 

Wall thickness: 0.31 inches
Tail length: 27 inches
Tail width: 29.3 inches

Total weight: 3,920
Charge/Weight ratio: 73%

Fuzing: Nose Pistol No.27, 42, or 44; Two side fuze pockets not used

Tail No: No.24 Mk I
  

Color and markings:  Dark Green overall
1/2 inch red band 1 inch from front edge of cylindrical shell,
2 inch light green band 16 inches from edge

Body Construction: The body is a cylindrical shell which has a hollow, conical nose piece welded to it, parallel sides, and a closing plate bolted to an angle ring.  The angle ring is welded in position a short distance inside the after end.  The shell is strengthened by a T-section beam welded to its inner surface.  Steel blocks, constituting pads for suspension lug and hoisting brackets, are welded in the angles of the beam,  The central tube is fitted over, and cemented to, the stem of the exploder container, extending almost to the closing plate.  Two exploder containers are fitted near the rear of the bomb at 45 degree angles to the strengthening beam.


Tail Construction: The tail is a cylinder of light-gauge plate, closed at rear by a diaphragm plate which is welded in position.  Tail securing screws thread into corresponding holes near the rear edge of the body shell.  The forward portion of the cylinder has saw-cuts between adjacent screw clearance holes, so that the tail can be sprung into the rear of the bomb body.
 
Suspension: A single suspension lug at the center of gravity is bolted to the body and internal strengthening beam.
  

Explosive Components:
Exploders:  Exploder containers house one solid and two perforate CE pellets.  The central tube is filled with 36 pellets of pressed TNT.

Main Filling: 2882 pounds of Amatol 60/40.


Remarks: This bomb may be fitted with a nose attachment to retard it in flight, consisting of a light-gauge plate around the forward end of the shell, which projects beyond it around the conical nosepiece.  Side fuze pockets are usually not used, but might contain a Time Pistol No.47.

HC 4,000lb Mks II and III (Obsolescent), and Mks IV, V, and VI (Service)

Overall length: 110 inches

Body length: 62 inches

Body diameter: 30 inches 

Wall thickness: 0.31 inches
Tail length: 27 inches
Tail width: 29 inches

Total weight: 3,930 pounds, Amatol filled
Charge/Weight ratio: 75%


Fuzing: Three nose pistols, Nos.27, 42, or 44; side fuze pockets on Mk II not used

Tail No: No.24 Mk I
  

Color and markings:  Dark Green overall
1/2 inch red band 8 inches from nose,
2 inch light green band 2 inches from nose

Body Construction: The body consists of a fabricated steel, cylindrical shell with a domed plate welded to the nose end, parallel sides, and a closing plate bolted to the angle ring, which is welded in position a short distance inside the after end.  The closing plate has a central adapter for a screw-ion plug and two drop handles.  The nose dome houses three exploder containers, the center one of which is extended through the body by a central tube.  The Mk II has two side fuze pockets near the rear of the body.  Mks II and III have strengthening beams running fore and aft, welded to the inner surface of the body, and acting as a pad for the suspension lug and hoisting brackets.  The Mk IV has steel blocks to support the suspension lug and hoisting brackets, and has no beam.


Tail Construction: The tail is a cylinder of light-gauge plate, closed at the rear by a diaphragm plate which is welded in position.  Tail securing screws thread into corresponding holes near the rear edge of the body shell.  The forward portion of the cylinder has saw-cuts between adjacent screw clearance holes, so that the tail can be sprung into the rear of the bomb body.
 
Suspension: A single suspension lug 43 inches from the nose dome is bolted to the bomb body and the steel support block.
  

Explosive Components:
Exploders:  CE pellets in exploder containers and central tube.


Main Filling:
-Mk II: 2954 pounds Amatol 60/40
-Mk III and IV: 2960 pounds Amatol 50/50 or 60/40, 3070 pounds RDX/TNT 60/40, 3088 pounds Minol 2, or 3294 pounds Torpex 2.


Remarks: These bombs may be fitted with a  nose attachment to retard them in flight, consisting of light-gauge plate around the forward end of the body shell which projects beyond it around the nose piece.  The side fuze pockets on the Mk  II are usually not used but might contain a Time Pistol No.47.

The Mk V is the same as Bomb Mk IV, but was made and filled in the US.   The Bomb Mk VI was made in US, and has a metal box for lugs and other fittings welded to the rear of the bomb body.

HC 8,000lb, Sectional, Mks I and II (Obsolescent)

Overall length: 133.6 inches

Body length:
-Front Section: 3 feet, 11.15 inches
-Rear Section: 3 feet, 11.75 inches

Body diameter: 38 inches

Wall thickness: 0.5 inches

Tail length:
-No.33 Mk I: 36.5 inches
-No.52 Mk I: 64 inches


Tail width: 37.8 inches

Total weight: 7,860 pounds, Amatol 9 filled
Charge/Weight ratio: 68%


Fuzing: Three nose pistols, Nos.27, 42, or 44

Tail No: No.33 Mk I, or No.52 Mk I
  

Color and markings:  Dark Green overall
1 inch bright red band,
2 inch light green band around each of the bomb body sections

Body Construction: The bomb consists of two cylindrical sections, each approximately 45 feet long and 3 feet, 2 inches in diameter, connected together by bolts.  The front section has a domed nose plate welded to the body, and houses three exploder containers.  A flat closing plate at the rear is bolted to an end ring, which is fitted with assembly bolts for connecting the two sections.  An additional exploder container is fitted into a central bush in the rear closing plate.  The rear section is closed at each end by plates.  The forward plate is welded to a channel ring having holes circumferentially located to receive the assembly bolts of the forward section.  The exploder container fits into the forward closing plate of the rear section.  Central exploder tubes extend through both sections.  Joining rings are cast in the Mk I and fabricated by welding in the Bomb Mk II.


Tail Construction: The Tail No.33 Mk I consists of a hollow steel-plate cylinder open at the after end, with an angle ring welded or riveted in its forward end.  The angle ring is drilled to take the assembly bolts of the rear body section for attaching the tail.  Hand clearance holes give access to the assembly bolts during assembling of the tail to the bomb.

The Tail No.52 Mk I has a cone with hand holes for access to the securing bolts, and a cylindrical strut attached tot he cone by six fins which are welded to both the strut and the cone.
 
Suspension: The bomb is suspended by a single suspension lug, secured by four bolts to steel block pads on the channel ring and immediately abaft the ring on the rear body section, 50 inches from the bomb nose.  This point represents the center of gravity.
  

Explosive Components:
Exploders:  All exploder containers and exploders in the central tube of both sections are filled with CE pellets.

Main Filling: 5361 pounds Amatex 9, or 5850 pounds Torpex 2.


Remarks: This bomb can be fitted with a cylindrical nose attachment, place around the nose of the forward section and protruding around the domed nose, to retard bomb in flight.  This bomb is not composed of two regular 4000 pound HC bombs, but of sections weighing approximately 4000 pounds, designed especially for it.

HC 12,000lb Mk II (Service)

Overall length: 196 inches

Body length: Each of three sections approx. 4 feet long

Body diameter: 38 inches 

Wall thickness: 0.5 inches


Tail length:
-No.33 Mk I: 36.5 inches
-No.52 Mk I: 64 inches


Tail width: 38 inches

Total weight: 11,936 pounds, Amatex 9 filled
Charge/Weight ratio: 70% (approx.)


Fuzing: Three nose pistols, Nos.27, 42, or 44

Tail No: No.33 Mk I, or No.52 Mk I
  

Color and markings:  Dark Green overall
1 inch bright red band,
2 inch light green band around each of the bomb sections

Body Construction: The bombs consist of three sections bolted together.  It is identical to the 8000 pound HC bomb, with an additional rear body section.  Joining rings are fabricated by welding, not cast as in Mk I section used in 8000 pound HC bomb.


Tail Construction: The Tail No.33 Mk I is a hollow-steel plate cylinder open at the after end, with an angle ring welded or riveted onto the forward end and drilled to take the assembly bolts of the rear body section for attaching tail.  Hand clearance holes give access to the assembly bolts.

The No.52 Mk I has a tail cone with hand holes for access to the securing bolts and a cylindrical strut, attached to the cone by six fins which are welded to the strut and cone.
 
Suspension: The bomb is suspended by dual suspension lugs, each secured by four bolts to the two channel rings connecting the three body sections.
  

Explosive Components:
Exploders:  CE pellets

Main Filling: 8040 pounds Amatex 9, or 8760 pounds Torpex 2

Next Time:  Semi-Armor Piercing, Armor Piercing, and Deep Penetration Bombs