Monday, 30 January 2017

British Explosive Ordnance - Flares and Photoflash Bombs







British Explosive Ordnance






Flares and Photoflash Bombs Introduction


This chapter includes the 4-inch, 4.5-inch, and 5.5-inch reconnaissance flares, the 7-inch hooded flare, the 4.5-inch photoflash bomb, and the 1.7-inch aircraft illuminator.


Reconnaissance flares are used as an aid in night reconnaissance, as an aid to night bombing, and to assist in emergency forced landings.  The general construction of these flares is the same, consisting of a flare body, a flare candle, and a parachute which supports the candle after the flare has functioned.  These flares can be stowed inside the aircraft and dropped from a launching chute, or they may be fitted to a bomb or flare carrier.  However, they are most commonly carried in Cluster Projectiles.

The hooded flare has the conventional flare body and parachute, and also a special flare candle to which an asbestos shield is attached.  This shield, which is folded when contained in the flare body and opens on ejection, deflects the intense glare from the burning candle downward.  This protects the vision of the personnel of the dropping plane, and allows much better observation.

Photoflash bombs are used to provide illumination for night photography.  They contain a flash composition, which explodes with a loud report and a vivid white flash to provide the intense, instantaneous illumination necessary for night photography.

Aircraft illuminators are small flares which contain illuminating stars, but no parachute.  They have a short, three-second period of illumination, and are used by intercepting aircraft for illuminating attacking enemy planes at night.


 
 


Aircraft Illuminator Flare No.1 Mks I and II (Service)
   

Overall length: 11 inches (Mk I); 11.2 inches (Mk II)
Body diameter: 1.7 inches
Total weight: 12 ounces (approx.)
Candlepower: 3,000,000
Burning time: 3 seconds (approx.)

Fuzing: Special, integral electrical fuze
  

Color and markings: Brown overall

  
Description: The flare consists of a cylindrical body, which houses three illuminating stars.  At the lower end of the body is a conical wooden nose, which insures easy entry of the flare into the funnel tube of an ignition chute.  The upper end of the body is closed by a wooden plug and a metal disc, the weight of which facilitates the passage of the flare through the chute and off-sets the up-draught and air drag as the flare leaves the aircraft.

Each star is primed at both ends and has a short strip of primed fabric wrapped around the star and held in position by two threads.  A long strip of primed fabric extends along the sides of the three stars is held in position by three additional threads, one around each star, at a position between the threads securing the short strip.

Between the metal disc and the top of the upper star is an aperture felt washer which contains a charge of gunpowder.  A primed fabric disc is located between the bottom of the lower star and the upper surface of the nose.  Vent holes are provided in the nose, whose open ends are sealed with paper sealing discs. 

Two copper strips pass along the outside of the body beneath a paper wrapper surrounding the body.  Their lower ends are connected to the leads from the electric fuze, and their upper ends emerge from, and are secured by, wire staples to the wrapper.  The portion of the outer surface of the paper wrapper surrounding the staples is sprayed with zinc to form contact bands.

The Flare No.1 Mk II is identical to the Flare Mk I, with the following exceptions.  The upper end of the body is closed by a metal cap, and the nose is made of moulded plastic material.  A pellet of delay composition is used instead of the length of delay safety fuze, and a length of quickmatch is located between the bottom of the lowest star and the priming composition.

   
Functioning: When the flare is launched through the ignition chute, the contact bands make rubbing contact with the spring wiper contacts in the chute, and the electric fuze is fired.  This fuze ignites the delay safety fuze, igniting the priming composition, which in turn fires the long primed fabric strip.  This strip initiates the short primed fabric strips, igniting the stars.  The gunpowder charge ejects the stars from the body.

When the Flare Mk II is launched, the electric fuze fires the pellet delay composition, initiating the priming composition.  This ignites the quickmatch, which in turn fires the long primed fabric strip.


Remarks: A delay of approximately two seconds occurs between the release of the flare and its ignition.








4-in Training Flare Mks I, III, IV, VII and VIII
 and 4-in Reconnaissance Flare, A.S. Mks I and II (Service)


Overall length: 30 inches
Body diameter: 4 inches
Tail diameter: 5.5 inches
Parachute diameter: 11 feet
Burning Time: AS flare, 50 seconds; Training flare, 3.25 minutes
Candlepower: Training flare, 500,000; A.S. flare, 2,000,000


Fuzing: Pull-percussion igniter
  

Color and markings:  Black with 1/2-inch red band near nose

  
Description: The 4-in Training Flare Body Mk IV comprises a front body portion containing a flare candle and a pull percussion igniter, and a rear body portion containing an 11-ft cotton parachute, which is connected with the candle unit.  The front and rear body portions are connected by a diaphragm, which closes one end of the front body and supports the flare candle and igniter.  Two suspension bolts on the diaphragm provide an anchorage for the parachute.  The opposite end of the front body is closed by a millboard disc held in place by a fusible closing disc.  In addition to the igniter plug, the igniter comprises an igniter body, which houses a striker mechanism, and into which the igniter plug is screwed.  The igniter body is held in place in the central tube by a retaining plate.

The A.S. Reconnaissance Flare is identical to the Training Flare except for a delay fuze below the igniter, which give about a 5-second delay before burning starts.


Functioning: When the flare is released, the long static cord, the free end of which has been attached to the rear crutch holder of the carrier or to the eyebolt on the lid of the launching chute, is withdrawn from the elastic loop and pulls the retaining pin out of the loop on one of the flaps, thus releasing all flaps.  The flare falls, with the parachute being drawn out of the body because of the connection between the short static cord and the long cord attached to the plane.  Tautening of the auxiliary static cord breaks the thin braided cord, separating the flare from the cord attached to the plane.

After the chute has opened, the body of the flare continues momentarily to fall freely until the suspension rope is fully tensioned.  The jerk as the suspension rope tightens causes the securing wire to bend and the clutch to be pulled out, spring-loading and releasing the striker.  The striker, when released, moves downwards and fires the percussion cap.  This flash ignites and fires the percussion cap.  This flash ignites the gunpowder in the training flare, sending a flash down the center tube by the primed cambric tube, igniting the burster charge.  (A percussion cap ignites the safety fuse in the A.S. flare.)  The flash from the burster charge passes through the holes in the apertured washer and ignites the primed cambric washer and the priming composition at the bottom of the flare candle.  The priming composition ignites the flare composition, being assisted by the six portions of igniter composition which ensure a substantially even ignition of the flare composition.  The fusible closing disc at the nose of the flare melts and permits the candle to burn freely.


Suspension: The flare has suspension band to which the lug is attached.


Remarks: The 4-inch Training Flare Mk I has a silk parachute, and a safety pin held by a split pin held by a split pin instead of a securing wire.  The flash from the gunpowder is conveyed to the burster charge by a length of instantaneous fuze instead of by a primed cambric tube as in the Flare Mk IV.  The 4-inch Training Flare Mk III has a silk parachute, but it is a stronger one than is used in the Flare Mk I.  The 4-inch Training Flare Mk VII has a slightly different cotton parachute than the Flare Mk IV.  The 4-inch Training Flare Mk VIII has an igniter fitted with a copper shear wire, which passes through holes near the top of the igniter body and in the clutch.  The shear wire is fitted to assist assembly during manufacture.  It is broken by the jerk which bends the securing wire and pulls out the clutch.  The parachute is similar to that of the Mk VII.

The 4-in A.S. Reconnaissance Flare Mk II has the same changes as 4-in Training Flare Mk VIII.

These flares are used primarily for training purposes, and, after being dropped from an aircraft, are supported by their parachutes even if they are not ignited.  The flares can also be used to assist in making an emergency landing during night flying.










4.5-inch Reconnaissance Flare Mks I, II, III, IV, and VII, and Target Flare Mk I (Service)
   

Overall length: 33 inches
Body diameter: 4.5 inches
Parachute diameter: 11 feet
Total weight: 23 pounds

Burning time: 3 to 4 minutes
Candlepower: 750,000


Fuzing: Nose Fuze No.35, 42, 848, or 849
May use No.28B Mks II or III, or No.860 with special permission.
  

Color and markings: Black overall with 1/2-inch red band around nose end

  
Description: The Flare Mk IV has a tubular body containing the candle unit, and a parachute, which is made of cotton.  The tail end of the body is closed by a closing dome, and has four tail fins.

The body is closed at the nose end by a diaphragm having a bush into which is screwed a nose plug or the fuze.  The flare composition is contained in a candle case together with some priming composition and a primed cambric disc at the nose end, a quantity of clay held between millboard discs, and a felt washer at the tail end.  A lid is riveted to the tail end of the candle case.  A shackle attached to the lid connects the candle unit with the suspension rope of the parachute.


Functioning: When the fuzed flare is released from the plane, the fuze is set in operation and the flare drops freely until the flash from the magazine charge of the fuze passes through the flash hole in the diaphragm and ignites the powder puff.  The gases formed by the burning of the gunpowder in the puff force the candle unit towards the closing dome.  The wooden slats push off the dome, thus permitting the candle unit and the parachute to be ejected from the flare body.  The flash from the puff ignites the primed cambric disc and the priming composition at the nose of the candle, and the priming composition ignites the flare composition.  The candle, which is now suspended on its parachute, continues to burn from the nose end until the flare composition is expended.


Suspension: A suspension band having two removable suspension lugs, one for attaching the flare to a Universal Bomb Carrier, and the other for attaching it to a Light Series bomb carrier, is secured to the flare body.  Seven flares may be carried in the Cluster No.1 Mk I, and four in SBC 250lb.


Remarks: The 4.5-inch Reconnaissance Flare Mk I is similar to the Flare Mk IV, but has larger tail fins, a Silk Parachute Mk II, a brass disc over the flash hole in the diaphragm, and a candle case which is not strengthened in the region through which the lid rivets pass.  The Reconnaissance Flare Mk II is similar to the Flare Mk IV, but has larger tail fins, a Silk Parachute Mk IV, a brass disc over the flash hole in the diaphragm, and a candle case which is not strengthened in the region through which the lid rivets pass.  The Reconnaissance Flare Mk III is similar to the Flare Mk IV, but it has larger tail fins and a brass disc over the flash hole in the diaphragm, and its candle case is not strengthened in the region through which the lid rivets pass.  The Reconnaissance Flare Mk VII is similar to the Flare Mk IV, but has a modified parachute known as the Parachute Mk VF.

The details of the Target Flare No.1 Mk I are generally the same as in the 4.5-inch Reconnaissance Flare Mk IV, except for the stencilled markings.  This flare is manufactured to give two types of steady colours, red or green, or four combinations of colors and stars; green with red stars, red with green stars, red with yellow stars, or green with yellow stars.  The red flare has a candlepower of approximately 250,000 while the green flare is rated at approximately 175,000 candlepower.  The flares themselves burn for approximately three minutes.  The stars, which burn for about 10 seconds, are ejected at intervals of approximately 20 seconds.









4.5-inch Reconnaissance Flare Mks V, VI, and VII (Service)
  
  
Overall length: 33 inches
Body diameter: 4.5 inches
Parachute diameter: 11 feet
Total weight: 23 pounds

Burning time: 3 to 4 minutes
Delay: 2 minutes
Candlepower: 750,000


Fuzing: Nose Fuze No.35, 42, 848, or 849; No.860 can be used only if specially authorized.
  

Color and markings: Black overall with 1/2-inch red band around nose end

  
Description: The Flare Mk V has a tubular body containing the candle unit and the Cotton Parachute Mk IVF.  The tail end of the body is closed by a closing dome, and has four tail fins.  The body is closed at the nose end by a diaphragm having a bush into which screws a nose fuze.  The flare composition is contained in a candle case, and at the nose end of the case is a quantity priming composition.  The filling of the candle is held in place at the nose end by a primed cambric disc and a millboard washer, and at the tail end by a felt washer and a lid secured to the candle case.  The lid is riveted to the candle case, and the rivets pass through a hessian or cotton canvas strengthening band around the candle case.  At the nose of the candle unit is a container in which is coiled a length of safety fuze, the ends of which are clamped and set in cement.  During manufacture, the end of the safety fuze which is ignited by the powder puff is cut square, dipped in moist powder.  The other or Inner end of the safety fuze terminates in a small quantity of igniter composition, and is covered by a shellacked paper tube and two shellacked paper discs.


Functioning: When the fuzed flare is released from a plane, the fuze is set in operation, and the flare drops freely until the magazine charge of the fuze bursts the paper disc covering the flash hole in the diaphragm.  The flash from the magazine charge passes through the flash hole and ignites the primed fabric of the powder puff and the strands of quickmatch, which in turn ignite the gunpowder in the powder puff.  The gases formed by the burning of the gunpowder in the powder puff force the candle unit toward the closing dome, thus permitting the candle unit and parachute to be ejected from the flare body.  The safety fuse is ignited by the flash from the gunpowder in the powder puff, and after a delay of two minutes, during which time the flare has fallen 2,000 feet supported by the parachute, the safety fuze ignites the igniter composition at its inner end.  The flash from the igniter composition is conveyed by the primed cambric disc to the candle primings, which are ignited and in turn ignite the flare composition.


Suspension: A suspension band around the body has two removable suspension lugs for attaching to a Universal Bomb Carrier, or a Light Series Bomb Carrier.  Seven flares may be contained in Cluster No.1 Mk I, and four in the 250lb SBC.


Remarks: The 4.5-inch Flare Mk VI is similar to the Flare Mk V, but is provided with a 4-minute internal delay, so that the flare falls 4,000 feet suspended on its parachute, before the candle is ignited.  The Flare Mk VIII differs from the Flare Mk V in that it has a modified parachute known as the 11-foot Parachute Mk VF.

The period of delay of these flares enables the aircraft which has released the flare to get into position for its bombing run and to make the best use of the three- to four-minute period of illumination given by the flare.








   


4.5-in Skymarker Flare No.1 Mks I, II, and III (Service)

  
Overall length: 33 inches
Body diameter: 4.5 inches
Parachute diameter: 11 feet
Total weight: 28 pounds (approx.)
Burning time: 100 seconds

Fuzing: Nose Fuze No.42, 848, or 849

Color and markings: Black overall with 1/2-inch red band near nose

  
Description: The flare has a tubular body containing the candle unit and the Parachute Mk V.  The tail end of the body is closed by a closing dome, and has four tail fins attached.  The nose end of the body is closed by a diaphragm to which a bush is secured.  The transit plug or the nose fuze is screwed into this bush.

A flash hole in the diaphragm is covered by a paper disc and gives access to a "powder puff" consisting of a primed cambric bag containing gunpowder.  The powder puff is secured to a perforated disc.  Its purpose is, with the aid of the perforated disc, to eject the candle unit and parachute from the flare body and to ignite the flare candle.

The candle unit comprises a steel container closed at the top by a lid and at the bottom by a dished washer.  In the container is a magnesium alloy candle body containing a small quantity of gunpowder, some priming composition, and a quantity of incendiary composition.  The hole in the washer is closed by a primed cambric disc.  The candle unit is held in place in the flare body by a felt washer, felt strips, and three wooden slats.  The slats extend beyond the top of the candle unit and the closing dome, and, when the flare is activated, push off the closing dome to permit the candle unit and parachute to move out of the flare body.  A shackle attached to the lid connects the candle unit to the suspension rope of the parachute.


Functioning: When the fuzed flare is released from the aircraft, the fuze is set in operation, and the flare falls freely until the magazine charge explodes.  The flash from the charge passes through the flash hole in the diaphragm and ignites the powder puff.  The gases formed by the burning of the gunpowder in the puff exert pressure on the under side of the perforated disc, forcing the candle unit toward the closing dome so that the wooden slats push off the dome.  The candle unit and parachute are ejected from the flare body.

The flash from the puff passes through the holes in the perforated disc to ignite the primed cambric disc and the gunpowder at the nose of the candle.  The gunpowder ignites the priming composition, which in turn ignites the incendiary composition.  As the incendiary composition burns, the magnesium alloy candle body also burns, and pieces of the burning candle fall away, giving the appearance of a vertical chain of white lights in the sky.


Suspension: A suspension band with two removable suspension lugs is secured to the flare body.  The lugs are secured to the suspension band by screws having a locking wire passing through their heads.  A crutch pad is also secured to the flare body.


Remarks: These flares are similar in external appearance to the 4.5-inch Reconnaissance Flare Mk IV.

The Flare Mk II is similar to the Mk I, except that, just below its lid, the candle unit is provided with a container filled with gunpowder.  This gunpowder is ignited by the incendiary composition and ejects any magnesium alloy which remains in the candle unit when the incendiary composition is expended.  This insures that odd pieces of burning magnesium alloy do not continue to fall after the flare has served its purpose.  The Flare Mk III is identical to the Mk II, except that the burning time has been increased to 120 seconds by use of a different type of incendiary composition, and of a steel container and magnesium alloy candle body which are 3 inches longer than those in the Flare Mk II.  The increased length of the candle unit is accommodated by reducing the space occupied by the parachute.











4.5-in Photoflash Bomb Mks I and II, and 4.5-in Heavy Photoflash Bomb (Service)


Overall length: 33 inches
Body diameter: 4.5 inches
Total weight: 19 pounds
Illumination time: 0.1 second (approx.)

Fuzing: Nose Fuze No.28B, 848, or 849; No.860 can be used only if specially authorized

Color and markings: Body black overall; tail red,
1/2-inch red band around nose end,
FLASH printed plainly on the body near the nose end.

   
Description: The Photoflash Bombs Mk I and Mk II are similarly constructed, the only difference being that the Mk II has narrower tail fins.  Each flash has a tubular body, closed at the tail by a closing dome and at the nose by a front diaphragm having a bush into which is screwed the nose fuze.  The four tail fins are located at the after end.  A quantity of flash composition is contained in the body between a front and rear diaphragm.  The filling hole is closed by a press-cap and overseal.  A central tube, closed at each end, extends between the front and rear diaphragms and is filled with gunpowder.  A socket secured to the front diaphragm houses a perforated disc, and a muslin disc, which closes the nose end of the central tube.  The perforated disc is held in position by a socket plug having a flash hole covered by a disc, which, in earlier issues, is made of brass, but in later issues is paper.


Functioning: When the fuzed bomb is released from an aircraft, its fuze is set in operation and the flash falls until the magazine charge of the fuze explodes.  The flash from the magazine charge passes through the perforated disc and ignites the gunpowder in the central tube.  The gunpowder explodes, bursts the body of the photographic flash, and simultaneously ignites the flash composition.
 

Suspension: The bomb is suspended by means of a suspension band to which are secured two suspension lugs, one for attaching to a Light Series Bomb Carrier, and the other for attaching to a Universal Bomb Carrier.

 
Remarks: These flash bombs are intended to provide illumination for night photography, and when activated they explode with a loud report and vivid white flash.  It is important to distinguish between flares and photoflash bombs.  They may be distinguished by the following characteristics.  FLASH is stencilled on the nose of all photoflash bombs, and the tail of the bomb is red.  Eight rivets are visible around the body at the junction of the red and black parts of the bomb.  On removal of the tail dome of a flash bomb, there is no parachute or shackle visible.

Externally, the 4.5-inch Heavy Photoflash Bomb is the same as the ordinary 4.5-inch photoflash.  Internally, the construction is slightly modified, as the rear diaphragm is moved to a position nearer the closing dome, consequently increasing the length of the central tube.  A retaining diaphragm is positioned in the body 5 and 1/2 inches from the front diaphragm.  A cast-iron weight is located between the front and retaining diaphragms, the flash composition being housed between the rear and retaining diaphragms.  The fuze is a US Mechanical Time Fuze Mk III which has a fuze adapter in order to fit it into the British bomb.  When it is loaded, the arming wire is fitted through the second hole in the arming wire is fitted through the second hole in the arming pin and passes through the arming vane lock.  The delay may be from 5 seconds to 93 seconds.  The heavy bomb weighs 40 pounds.






 




5.5-in Reconnaissance Flare Mk I and II (Obsolescent)


Overall length: 48 inches
Body diameter: 5.5 inches
Parachute diameter: 18 feet
Total weight: 41.5 pounds
Burning time: 3 minutes, 15 seconds to 4 minutes, 15 seconds
Candlepower: 1,000,000 (approx.)

Fuzing: Nose Fuze No.28B, 42, or 848; may use No.35 or 849; No.860 can be used only if specially authorized

Color and markings: Black overall with 1/2-inch red band 5 inches from the nose.

Description: The Flare Mk II has a tubular body, which contains the flare-candle unit and its parachute.  The body is closed at its nose end by a diaphragm having a bush into which is screwed a nose fuze.

The tail end of the body is closed by a closing dome and has four tail fins.  The diaphragm has a flash hole, sealed by a thin metal disc.  A powder puff, consisting of a primed fabric bag containing gunpowder and strands of quickmatch, is located in position by washers, and a perforated disc to which it is secured.  The candle unit comprises a candle case containing the flare composition and a quantity of priming composition.  The nose end of the case is closed by a primed cambric disc and a millboard washer, and the tail end is closed by a lid.  A shackle attached to the lid connects the candle unit with the suspension rope of the parachute.


Functioning: When the fuzed flare is released from a plane, the fuze is set in operation and the flare falls freely until the magazine charge of the fuze is fired and perforates the metal disc covering the flash hole in the diaphragm.  The flash from the magazine charge passes through the flash hole and ignites the primed fabric of the powder puff and the strands of quickmatch, which in turn ignites the gunpowder in the powder puff.  The gases formed by the burning of the gunpowder in the puff force the candle unit towards the closing dome, and the wooden slats push off the closing dome and permit the candle unit and parachute to be ejected from the flare body.  The parachute then opens and supports the candle unit.  Before ejection, the candle is ignited by the flash from the gunpowder in the powder puff; this flash being conveyed by the primed cambric disc at the nose end of the candle case to the priming composition, which, in turn, ignites the flare composition.

 
Suspension: A suspension band with lug is provided for attachment to a Universal Bomb Carrier.


Remarks: The 5.5-inch Reconnaissance Flare Mk I is similar to the Flare Mk II, except that the duration of burning is approximately 3.5 minutes, and a Parachute Mk I, which is not as strong, is used instead of a Mk II.








7-in Hooded Reconnaissance Flare No.1 Mk I, No.2 Mk I, No.3 Mk I, and No.4 Mk I (Service)


Overall length:
-No.1: 63 inches
-No.2, 3, and 4: 60 inches

Body diameter: 7 inches
Total weight: 85 pounds (approx.)
Burning time: 3 minutes to 4 minutes
Candlepower: 750,000

Fuzing:
-No.1: Nose Fuze No.848
-No.2, 3, and 4: Initiator No.C5 Mk I

Color and markings: Black overall with 1/2-inch red band 5 inches from the nose.

  
Description: The Flare No.1 consists of a flare-candle unit contained in a thin metal case, which is fitted with a heavy nose, and closed at the tail end by a metal closing cap.  Housed in the rear of the casing is the parachute attached by the shackle to the candle unit.  A metal tube containing a primed cambric tube connects the powder puff in the nose of the flare with the candle cap.  A length of safety fuze, sealed at each end with a celluloid cap containing a small gunpowder charge, passes through the candle cap to the gunpowder charge contained in the nose of the candle.  Attached to the side of the candle unit is a frame to which is fixed the sheet asbestos hood which directs the light downward and shields the eyes of the bombardier from the glare.  The form, which folds around the candle unit, has a square cross section when open and extends beyond the ends of the candle unit.  The tail end of the hood is partially closed by a deflector.

In the Flare No.2, the heavy nose and the suspension band are omitted, thereby reducing the weight.  The Flare No.3 is the same as the No.1 except that it incorporates a 2 and 1/2 minute delay; and the Flare No.4 is also the same as the No.1 except that it has three 14-foot parachutes.

 
Functioning: On release from the aircraft, the flare falls in a normal manner until the fuze forces the parachute and candle unit out of the metal case, at the same time igniting the primed cambric.  The primed cambric ignites the celluloid cap of the safety fuze, and after a short delay the safety fuze fires the gunpowder charge in the nose of the candle.  The explosion of the gunpowder forces off the candle cap, at the same time igniting the flare composition.  The short delay in the fuze allows the parachute and hood to open before the flare functions.

 
Suspension: The Flare No.1 is carried singly by a suspension lug on a band fastened around the body.  Flares No.2, 3, and 4 are carried in Cluster No.3 Mk I, four flares in each cluster.


Remarks: The Hooded Flares No.2, 3, and 4 are each fuzed with a 5-sec Delay Initiator No.C5 Mk I.  These initiators are ignited by the functioning of the cluster fuze to give simultaneous and individual initiation to each flare after the cluster has disintegrated.



 



Next Time: Aircraft Pyrotechnics Part 1

Monday, 23 January 2017

British Explosive Ordnance - Target Identification Bombs









British Explosive Ordnance







Target Identification Bombs Introduction



Target Identification bombs are designed to illuminate or mark a target for night bombing.  Not all TI bombs are filled with flare candles.  Some of them, such as the photoflash and sea marker TI bombs, contain special fillings.  But, because the majority of these bombs do contain candles, the following explanation is given in order to simplify the discussion of the bombs.
Three general types of candles are employed.  They are the non-delay, delay, and explosive candle.  The non-delay candle may give illumination of various colours, and, as the name indicates, the candle commences to function immediately on initiation.  This type of candle gives a sky marking effect due to the illumination given off during its fall.
The delay candle may also give illumination of various colours, but only after a period of delay, the length of which is determined by the delay unit contained in the candle.
The explosive candle is used in ground marker bombs, which contain a percentage of these candles to discourage interference with marker candles.  They contain an illuminant which burns until it ignites the explosive charge.  This explosive charge is also a component of the candle. 
The specific types of candles are listed as follows:
-Type A- These are non-delay candles of three minutes duration giving red, green, or yellow illumination.
-Type B1- These are delay candles which burn for a period of approximately two minutes with a red, green, or yellow light after a delay of two and one half or five minutes.
-Type B2- These are delay candles which burn with a red, green, or yellow light.  The delay and period of illumination depend upon the relative amounts of the two compositions.
-Type B3- These are long-delay candles which employ safety fuse to give a delay of from thirteen to thirty minutes.  The candles burn with a red, green, or yellow light for approximately three minutes.
-Type C- These candles burn with a red, green, or yellow light when initiated.  A delay composition separating the two illuminant sections provide a delay of two and one half to eleven minutes between sections.  This flare has two burning periods.
-Type D- These are explosive candles which burn with a red, green, or yellow light until the explosive charge is ignited.
-Type E- These are explosive candles whose illuminant is ignited by safety fuse after a delay of from fifteen to thirty-one minutes.  The illuminant burns with a red, green, or yellow light for approximately two minutes, after which it ignites the explosive charge.
-Type F- This is an explosive candle with two illuminant sections separated by delay composition.  The delay is from two and one half to nine minutes, depending on the amount of flare composition, which burns red, green, or yellow.  The second illuminant section ignites the explosive charge.
-Type G- These are non-delay candles equipped with parachutes to give a skymarker effect.  They provide red, green, or yellow illumination for approximately three minutes.
-Type H- This is a non-delay candle, which contains alternate coloured flare pellets of red and yellow, red and green, or yellow and green.  Each pellet burns for approximately fifteen seconds, giving a total burning time of approximately five and one-half minutes.
-Type J- This is another non-delay candle containing alternate colored pellets, as well as an explosive charge.  The flare burns for approximately two, three, or four minutes before exploding, depending on the number of pellets it contains.
-Type K- These non-delay candles are similar to and burn with the characteristic white illumination of the 4 pound Incendiary bomb, but have a different ignition system.
-Type L- These are white, non-delay candles similar to the Type K, but having a steel nose containing a high explosive charge, which explodes after a delay period subsequent to the illuminant's burning out.
-Type M- These are non-delay, change-colour candles similar to the Type H but having a three-minute overall burning time.  The colour changes are red and yellow, yellow and green, or red and green.
-Type N- These are non-delay, change-colour, explosive candles similar to the Type J, but having a period of illumination of two minutes and colour combinations of red and yellow, yellow and green, or red and green.
-Type P- This is a delay candle which burns red, yellow, or green before exploding.  The illuminating time depends on the relative quantity of delay composition and illuminant.
-Type Q- This is a delay candle which gives a succession of white flashes of long and short duration arranged in sequence as a Morse code signal.  A delay of three quarters of a minute to twenty-three minutes is provided by safety fuse.
-Type R- This is a non-delay candle, which gives a succession of white flashes of long and short duration arranged as a Morse code signal.
-Red Flash Unit- This flash unit gives a red flash of short duration after a predetermined delay period.
TI bombs are painted black overall with a coloured band around the nose plug to indicate flare color, and a 1/2-inch red filling band 8 inches from the nose.  The colour of the flares is also stencilled on the bomb body.  A red cross near the base of the bomb indicates that explosive candles are used.
The corresponding marks of the 250lb bombs No.1-6, 9, 10, 15, 16, 17, and 23-28 are identical in construction and operation, differing only in the fillings.  Consequently these bombs are groups for purposes of description.
The 1000lb TI bombs are larger versions of the 250lb size and correspond according to the "Number" in the designation.  Thus the TI 1000lb No.B22 would be the enlarged equivalent of the TI 250lb No.22 Bomb.


 
 




TI 250lb (Service)
(No.1 Mks I, IC, II, and III; No.2 Mks I, II, and III; No.3 Mks I, IC, II, and III; No.4 Mks I, IC, II, and III; No.5 Mk I; No.6 Mk I; No.9 Mk I; No.10 Mk I; No.15 Mk I; No.16 Mks I, IC, II, and III; No.17 Mks I and III; No.23 Mks IC, and III; No.24 Mks IC, and III; No.25 Mks IC, and III; No.26 Mk III; No.27 Mk III; and No.28 Mk III)
Overall length: 61.7 inches
Body diameter: 12 inches
Tail length: 27.2 inches
Tail width: 11.7 inches
Total weight: 220 pounds (approx.)


Fuzing: Nose Fuzes No.860 Mk II, No.848, or No.896 Mk I; Tail Fuze No.867 Mk I
  
Tail No.: Bombs Mks I and II; No.1 Mk II, No.35 Mk I, or No.75 Mk II; Bombs Mk IC and Mk III; No.75 Mks I or II.

Color and markings: The bomb body is painted black overall with a coloured band around the nose to indicate the flare colour, and a 1/2-inch red band 8 inches from the nose.

The colour of the flare is also stencilled on the bomb body.  A red cross near the rear of the bomb indicates that explosive candles are used.

  
Body Construction: The corresponding marks of the numbered bombs listed in this section are identical in construction and operation.  They differ only in the types of candles they contain.  Bombs Mk I and Mk II are nose-fuzed only, while Mks IC and III have provisions for both nose and tail fuzing.

Mk I Body - The Mk I bomb body consists of a heavy-gauge steel tube, to one end of which is welded a steel nose.  The after end of the body is closed by a tail plate held in place by six brass rivets.  The tail plate has two bayonet slots and a hole to be engaged by a transit base or the tail unit.

In the nose of the bomb is located the burster container, which houses a 3-ounce black powder ejection charge in a cambric bag or celluloid container.

Immediately abaft the burster container is the ejection plate, slightly smaller than the internal diameter of the bomb body, to which the central flash tube is welded.  The division disc, which separates the two layers of candles, is located at the opposite end of the flash tube.  The inside of the tube and both sides of the division disc are covered with primed cambric.  The igniter ends of both layers of candles rest against one of the primed discs.

The candles are held in position in the bomb body by felt or corrugate paper strips lining the inside of the body, a number of notched packing discs located beneath the tail plate, and a notched washer located against the ejection plate.  Three equi-spaced wooden battens, which pass through notches in the division plate, extend between the ejector plate and tail plate in order to force off the tail plate when the bomb functions.


Mk II Body: The Mk II bomb body is identical to the Mk I except for the use of a different type of suspension lug, and a light-gauge steel body which necessitates the use of a cast-iron weight welded inside the nose.




Mk III Body: The body of the Bomb Mk III consists of a light-gauge steel tube which has a steel nose welded to one end.  A cast-iron weight is welded inside the nose section.  The after end of the body is closed by a tail plate held in position by three locating studs, which engage three slots in the after end of the body, and is secured in position by three brass rivets.

The tail plate has two bayonet slots and a hole to be engaged by pins on a transit base, or the securing screws of the Tail Unit No.75 Mk I or Mk II.  A V-slot in the skirt of the tail plate, aligned with one of the locating studs and diametrically opposite the hole, receives the locating pin on the Tail No.75 to assure that the tail slot for the tail fuze lanyard is aligned with the suspension lug of the bomb.  The suspension lug is of the same type used on the Mk II body.

The burster container is similar to that of the Bomb Mk I, but is welded to the ejector plate and internally threaded to receive the forward end of the central flash tube.  The after end of this tube threads into the tail-fuze adapter, which is locked in place, and the whole adapter, which is locked in place, and the whole assembly is secured to the tail plate by a locking ring.

The two layers of candles are separated by a division disc, and a priming system, similar to the one used in the Bomb Mk I, is used to ignite them.  The candles are positioned as in the Bomb Mk I, but the wooden battens are not used as the central flash tube serves to force off the tail plate when the bomb functions.

 
Mk IC Body: This bomb is very similar to the Mk III, but as it employs a Mk I body converted for tail fuzing, its body is of thick-gauge steel, and consequently the nose weight is dispensed with.  The central tube is welded to the inner end of the burster container and is also welded to the ejector plate.




Functioning:
-Mks I and II: When the bomb is dropped, the fuze is set in operation and the bomb falls freely until the fuze explodes, igniting the burster charge of the bomb.  The flash from the burster charge passes through the flash hole in the burster container, and is conveyed to the primer cambric discs on the division disc by the primed cambric in the central flash tube.  These division discs ignite the candles.

Simultaneously, the gases from the burster charge expand and force the ejector plate toward the tail of the bomb.  The wooden battens force the tail plate and tail off the bomb, and the ignited candles are ejected and function in the normal manner.


-Mks III and IC: If the bomb is tail-fuzed only, the functioning of the fuze produces a flash which ignites the primed cambric in the central flash tube.  This primed cambric conveys the flash to the burster charge, which it ignites, and also passes through holes in the central tube to ignite the primed cambric discs on either side of the division disc.  These in turn ignite the candles.

Simultaneously, the explosion of the burster charge shatters the burster container at a weakened point, and the gases formed force the ejector plate toward the tail of the bomb.  The central tube forces off the tail plate and tail unit, and the candles are ejected to function in the normal manner.

If the bomb is nose-fuzed only, it will function in a similar manner except that he burster charge is ignited directly by the flash from the fuze magazine and the primed cambric tube is ignited by the burster charge.

  
Tail Construction: The Tail Units No.1 Mk II, and No.35 Mk I consist of a tail-cone to which a cylindrical strut is attached by four fins.  Three screws secure the tail to the tail plate of the bomb.

The Tail Assembly No.75 Mk I consist of a tail cone to which a cylindrical strut is attached by four fins.  Three screws attach the cone to the tail plate of the bomb, and a locating pin engages a V-slot in the tail plate to position the tail.  An arming assembly, consisting of an arming spindle, arming vanes, and an arming-spindle fork, is also present.  The Tail Mk II has cut-away fins to allow the arming vanes to be recessed for protection.  Both the Tails Mk I and Mk II have inspection windows in the tail cone.


Suspension: The bomb is suspended by a single lug, which is welded to the body.




Filling:
-No.1 Mk I - 60 Type A or 62 Type K candles
-No.1 Mks I and III - 60 Type K candles
-No.1 Mk II - 60 Type A candles
-No.2 Mk I - 56 Type A and 4 Type D candles, or 56 Type K and 4 Type L candles
-No.2 Mks II and III - 56 Type A and 4 Type D candles
-No.3 Mks I, IC, II, and III - 20 Type A and 40 Type B1 candles
-No.4 Mks I, IC, II, and III - 16 Type A, 40 Type B1, and 4 Type D candles
-No.5 Mk I - 30 Type A and 30 Type B1 candles
-No.6 Mk I - 26 Type A, 30 Type B1, and 4 Type D candles
-No.9 Mk I - 60 Type C candles
-No.10 Mk I - 60 Type B1 candles
-No.15 Mk I - 30 Type A and 30 Type D candles
-No.16 Mks I, IC, II, and III - 9 Type A, 46 Type B2, and 4 Type F candles
-No.17 Mks I and III - 60 Type M candles
-No.23 Mks IC and III - 9 Type A and 39 Type B2 candles
-No.24 Mks IC and III - 11 Type A, 45 Type C, 1 Type D, and 3 Type F candles
-No.25 Mks IC and III - 23 Type B2, 19 Type B3, 1 Type D, 1 Type E, and 2 Type F candles
-No.26 Mk III - 11 Type A, 27 Type B2, 18 Type C, 1 Type D, 1 Type F, and 2 Type P candles
-No.27 Mk III - 39 Type Q and 1 Type R candles
-No.28 Mk III - 16 Type A, 40 Type C, and 4 Type D candles












TI 250lb Multi-Flash No.7 Mks I and II, and No.21 Mks I, II, III, and IC (Service)

    
Overall length: 67.75 inches
Body diameter: 12 inches
Tail length: 27.2 inches
Tail width: 11.7 inches
Total weight: 220 pounds (approx.)

Burning Time: 0.1 seconds (individual unit)
 5 minutes (total contents of bomb)


Fuzing: Nose Fuze No.860 Mk II, No.848, or No.896 Mk I

Tail No.: No.1 Mk II, No.35 Mk I, or No.75 Mk II
  

Color and markings:  The bomb is painted black overall with a 1/2-inch red filling band located 8 inches from the nose.

MULTI-FLASH RED is stencilled in red letters on the nose, and in white letters on the body.

  
Body Construction:
-No.7 Mks I and II and No.21 Mks I and II Bodies: The actual construction of these bombs is the same as that of the No.1 TI Bomb Mk I except for a different arrangement of the filling, which requires a different type of central flash tube and priming, and eliminates the use of the division disc.

The flash units are packed around the central tube in seven layers, each of which contains 26 units; and an eight layer, containing 28 units, is positioned above the central tube.  The flash units are positioned so that the primed ends of each two layers contact one of the four primed cambric washers for purposes of ignition.  Each of these washers engages a strip of primed cambric, which is secured around a set of holes in the central tube.

The Bomb No.7 Mk II differs from the No.7 Mk I as the No.1 Mk II differs from the No.1 Mk I.


-No.21 Mk III and IC Body: The body, tail plate, burster container, and ejector plate of this bomb are the same as in the TI Bomb No.1 Mk I.  The interior arrangement of the Bomb No.21 Mk III differs from the No.7 and No.21 Mks I and II in that he central flash tube extends completely through the bomb to the tail fuze pocket, thus displacing two of the flash units.  The Bomb No.21 Mk IC differs from the No.21 Mk III as the No.1 Mk IC differs from the No.1 Mk III.


Functioning:
-No.7 Mks I and II, and No.21 Mks I and II: The explosion of the fuze magazine ignites the burster charge, which transmits its flash to ignite the primed cambric tube, the primed strips around the central tube, the primed washers, and the flash units.  The ejection of the flash units is the same as for the Bomb No.1 Mk I.

-No.21 Mk III and IC Bombs: The operation of these bombs, when nose-fuzed, is the same as that for the Mks I and II of the TI Bombs No.7 and No.21.  When tail-fuzed, the flash is transmitted from the tail fuze to the nose burster by the primed cambric tube which meanwhile ignites the units.  Ejection is the same as for the Bomb No.1 Mk III.


Tail Construction: Same as for the No.1 TI Bomb tails.


Suspension: The bomb is suspended by a single lug, which is welded to the body.


Filling:
-No.7 Mks I and II, and No.21 Mks I and II: 210 red flash units
-No.21 Mks III and IC: 208 red flash units.




Remarks: This bomb is used to distinguish genuine ground markers from one simulated by the enemy.













TI 250lb Spot Fire, No.8 Mks I, IC, II, and III (Service)
   

Overall length: 57.75 inches
Body diameter: 12 inches
Tail length: 27.2 inches
Tail width: 11.7 inches
Total weight:
-Mk I and IC: 205 pounds
-Mk II and III: 215 pounds

Burning time: Red, 20 min (approx.); Green and Yellow, 1 hour (approx.)


Fuzing: Nose Fuze No.860 Mk II, No.848, or No.896 Mk I; Tail Fuze No.867 Mk I

Tail No.: No.1 Mk II, No.35 Mk I, or No.75 Mk II
  

Color and markings: The bomb is painted black overall with a 1/2-inch red filling band, 8 inches from the nose.

SPOT FIRE in red, green, or yellow letters, according to the filling, is stencilled on the nose;
and SPOT FIRE, preceded by the appropriate colour, is stencilled on the body in white.

  
Body Construction:
-Mk I Body: The bomb body, tail plate, and burster are the same as those used in the TI Bomb No.1 Mk I.  However, the burster container has a crossed slit on its inner end, filled with solder, to pass the flash from the burster charge to an igniter located in the impregnated bale.

The ejector plate is held by screws against a steel ring welded to the inside edge of the nose.  The ejector plate has a central flashhole covered by a thin copper disc, which has two crossed slits filled with solder.  Three locating pins are welded to the ejector plate, and locate the bale igniter centrally over the flash hole.

The filling bale consists of rolled cotton wool enclosed in cheesecloth, and held together by wire and steel bands.  Six wooden battens extend from the ejector plate to the tail plate and serve to force off the tail plate when the bomb functions.

The igniter at the nose end of the bale consist of an igniter base into which a tube filled with incendiary composition is screwed.  A central hole in the igniter base is located above the flash hole in the ejector plate, and has a similar closing disc of copper with a solder-filled cross slit.

A diaphragm, soldered to the bomb body under the tail plate, holds the bale in place.


-Mk II Body: The Bomb Mk II differs from the Mark I only in general body construction as the TI Bomb No.1 Mk II differs from the No.1 Mk I.


-Mk III Body: The Bomb Mk III is similar in body and tail plate construction to the TI Bomb No.1 Mk III.  The internal arrangement of the filling is similar to that in the Bomb No.8 Mk I.  However, as this bomb is arranged for tail fuzing, a length of instantaneous fuze leads from the tail fuze pocket, through a steel tube located along the inside of the bomb body, and into the forward end of the burster container.  A burster capsule is attached to each end of the fuze.


-Mk IC Body: The Mk IC bomb differs from the Mk III as the TI Bomb No.1 Mk IC differs from the No.1 Mk III.



Functioning:
-Mk I and II: The functionining of the fuze ignites the burster charge, which simultaneously ruptures the three soldered cross slits to initiate the incendiary charge in the igniter, and forces the ejector plate toward the rear, causing the wooden battens to push off the tail plate and eject the bale.  The incendiary charge in the igniter heats its tube until the impregnated cotton wool in the bale catches fire.

-Mk III and IC: The operation, when nose-fuzed, is the same as for the Mks I and II, and, when tail-fuzed, differs only in that the flash from the tail-fuze magazine is transmitted to the burster container by the instantaneous fuze, where the burster charge is ignited by the burster capsule.


Tail Construction: Same as for the TI Bomb Tails No.1


Suspension: The bomb is suspended by a single lug, which is welded to the body.



Filling: The filling consists of a bale of color-impregnated cotton wool.


  







TI 250lb Photoflash, No.11 Mk I, No.12 Mk I, and No.13 Mks I and II (Service)
    

Overall length: 67.75 inches
Body diameter: 12 inches
Tail length: 27.2 inches
Tail width: 11.7 inches
Total weight: 220 pounds (approx.)
Flash illumination period: 0.1 second


Fuzing: Nose Fuze No.860 Mk II, No.848, or No.896 Mk I

Tail No.: No.1 Mk II, No.35 Mk I, or No.75 Mk II
  

Color and markings:  The bomb is painted black overall with a 1/2-inch red filling band 8 inches from the nose.  A coloured band on the nose indicates the color of the candles in the bomb, while the colour is also stencilled in the appropriate shade on the body.

PHOTOFLASH is stencilled in white letters on the nose.

  
Body Construction: The Bombs No.13 Mk I and Mk II have bodies, base plates, and burster containers identical to those of the corresponding marks of the TI Bombs No.1.

The ejector plate is perforated and has a wooden block attached to it by screws.  This block houses the photoflash igniter.  The photoflash unit has a thin metal body, and a central burster tube filled with black powder.

The candles are arranged in two layers around the central flash unit.  A primed cambric washer is located between the primed ends of the two layers.


Functioning: When the fuze functions, it ignites the burster charge, whose flash initiates both the photoflash igniter and the primed cambric disc, which ignites the candles.  The expanding gases of the burster eject the flare contents.  The candles function in their normal manner, and the photoflash unit explodes with a vivid, white flash about two seconds after ejection.


Tail Construction: Same as for the No.1 TI bomb tails.


Suspension: The bomb is suspended by a single lug, which is welded to the body.


Filling: The filling of the Bomb No.13 consists of a photoflash unit, and 40 Type A candles.


Remarks: Both the 250lb TI Bombs No.11 and No.12 were manufactured in limited numbers, and have been superseded by the Bomb No.13.  Both bombs were similar to the No.13 but the No.12 was filled with 40 Type B1 candles packed around the photoflash unit, while the No.11 contained no candles, the space being packed with sand to act as a ballast.






 






TI 250lb Skymarker (Service)
(No.14 Mks I, IC, II, and III, and Change Color, No.18 Mks I, IC, II, and III)




Overall length: 67.75 inches
Body diameter: 12 inches
Tail length: 27.2 inches
Tail width: 11.7 inches
Total weight: 220 pounds (approx.)
Burning Time: No.14 - 3 minutes; No.18 - 5 and 1/2 minutes


Fuzing: Nose Fuze No.860 Mk II, No.848, or No.896 Mk I; Tail Fuze No.867 Mk I

Tail No.: No.1 Mk II, No.35 Mk I, or No.75 Mk II
  

Color and markings:  The bombs are painted black overall with a 1/2-inch red filling band 8 inches abaft the nose.

The Bombs No.14 have a coloured nose band to indicate the colour of the candles used, as well as having the colour stencilled on the bomb body.  SKYMARKER is stencilled on the nose and body in white.

The Bomb No.18 has two 1/2-inch rings around the nose to indicate the colours are also stencilled on the bomb body.  CHANGE COLOUR is stencilled on the nose and body in white.

  
Body Construction:
-No.14 Mks I and II, and No.18 Mks I and II: The body, tail plates, and burster containers of these bombs are the same as those of the No.1 Mks I and II.  In addition, the No.14 Mk I has a nose weight of cast iron.  The Bombs No.14 and No.18 have no central flash tube, but use double-length candles, whose primed ends rest against a primed cambric disc on the perforated ejector plate.  Steel tubes may be substituted for wooden battens.

-No.14 Mks III and IC, and No.18 Mks III and IC: The body, tail plate, burster container, central flash tube, and tail-fuze adapter of these bombs are identical to those on the corresponding marks of the TI Bombs No.1.  The Nos.14 and 18 have an unperforated central tube and no division disc, as double-length candles are used.  The candle's primed ends rest against a primed cambric disc on the perforated ejector plate.


Functioning:
-No.14 Mks I and II, and No.18 Mks I and II: Functioning of the fuze ignites the burster charge, which flashes through the perforated ejector plate to ignite the cambric and candles, and ejects the candles after forcing off the base plate.

-No.14 Mks III, and IC, and No.18 Mks III and IC: If nose-fuzed, these bombs fuction the same as the Mks I and II, except that the central tube instead of battens forces off the tail plate.  If tail-fuzed, the flash of the fuze is carried by the primed cambric tube to the nose burster charge, after which the operation is the same.


Tail Construction: Same as for the TI Bomb Tails No.1


Suspension: The bomb is suspended by a single lug, which is welded to the body.


Filling:
-No.14: 24 Type G candles
-No.18: 24 Type H candles















TI 250lb, Sea Marker, No.19 Mks I and II (Service)


Overall length: 67.75 inches
Body diameter: 12 inches
Tail length: 27.2 inches
Tail width: 11.7 inches
Total weight: 180 pounds (approx.)
Burning time: 5 to 8 minutes (approx.)


Fuzing: Nose Fuze No.860 Mk II, No.848, or No.896 Mk I

Tail No.: No.1 Mk II, No.35 Mk I, or No.75 Mk II
  

Color and markings: The bomb is painted black overall with a 1/2-inch red filling band 8 inches from the nose.

SEA MARKER-FLAME is stencilled on the nose, and SEA MARKER is stencilled on the bomb body.


Body Construction: The body, tail plate, and burster container of the Bombs No.19 Mk I and Mk II are the same as those of the corresponding marks of the TI Bombs No.1.

The ejector plate is secured by screws to a ring, which is welded to the inner edge of the nose.  A canister of thin steel rests on the ejector plate, and is held in position by a thin diaphragm soldered to the inside of the body just beneath the tail plate.  The inside of the canister is divided in two by a thin dished plate.  The upper part of the canister forms a buoyancy chamber, while the lower part is filled with a sodium phosphide-phosphorus mixture.  The lower part of the canister is pierced by several water-inlet holes, which are covered by wire netting.  Six wooden battens extend along the outside of the canister to force off the tail plate.


Functioning: When the fuze functions, the flash from its magazine ignites the burster charge, which forces the ejector plate aft, shearing its securing screws and ejecting the canister.

When the canister falls into the sea, the buoyancy chamber keeps it afloat while water enters the inlet hole and reacts with the chemical filling to produce impure phosphine gas.  This gas escapes through the water-inlet holes and ignites spontaneously on contact with air go vie a luminous flame about three feet long, as well as a cloud of dense smoke.


Tail Construction: Same as for the No.1 TI bomb tails.

 

Suspension: The bomb is suspended by a single lug, which is welded to the body.

  

Filling: The bomb is filled with a sodium phosphide-phosphorus mixture.








 




TI 1000lb (Service)
(No.B2 Mk I, No.B4 Mk I, No.B16 Mk I, No.B22 Mk I, No.B24 Mk I, No.B25 Mk I, No.B26 Mk I, No.B28 Mk I, and No.B29 Mk I)
  



Overall length: 73.6 inches
Body length: 53.6 inches
Body diameter: 17 inches
Tail length: 20 inches
Tail width: 17.4 inches
Total weight: 560 pounds (approx.); No.B29 - 730 pounds (approx.)

Fuzing: Tail Fuze No.867 Mk I, or Nose Fuze No.896 Mk I.
 Bomb No.B29 is nose-fuzed only, with Nose Fuzes M111, M111A1, M111A2, No.42 Mks II, II*, IM, or III, No.848 Mks I-V, or No.849 Mks I or III.

Tail No.: No.57 Mk I
  

Color and markings: Black overall,
red band around nose end, and 2-inch ring around nose to indicate colour of contents,
"X" stencilled in red when explosive candles are used.


Body Construction: The bomb consists of a cylindrical body with a dome-shaped nose cap welded on.  The after body of the bomb consists of a sheet steel body cone.  This after cone section is welded to a steel tail plate, which is press-fitted into the after end of the central cylinder.  A small notch is cut out at one point on the circumference of the tail plate.  A projection from the end of the central body engages in this notch, properly positioning the tail plate and tail assembly.  A steel tube, running axially through the bomb, is welded to a burster container at the nose end, and passes through a central hole in the tail plate at the tail end.  The fuze adapter is threaded to this tube abaft the closure plate, holding the closure plate and tail assembly tightly in the bomb body.

Three banks of flares are placed in the central body cylinder.  The ignition ends of the flares bear against one of two equi-spaced, primed cambric discs.  A primed cambric tube is inserted in the central tube, and holes in the central tube provide a lead out to each of the primed cambric discs.

An ejection plate is located just before the first bank of flares and just abaft the hollow nose portion of the bomb.  This ejection plate is welded to the central tube.  In the nose is a short burster container with a flash hole in its after end, and additional flash holes located circumferentially around its upper portion.  These latter holes lead into the empty cavity formed by the nose portion of the bomb and ejection plate.

The Bomb NoB29 is the only bomb of this series which does not contain candles.  It is similar to the Bomb No.B2, but has no primed cambric tube in the central tube, and no primed cambric, cardboard, or millboard washers in the bomb body.  The bomb is filled with a quantity of powdered, coloured pigment.




Tail Construction: The Tail No.57 Mk I consists of a tail cone to which a cylindrical strut is fastened by four fins.  The arming assembly consists of arming vanes, an arming spindle, and an arming fork, which is positioned inside the cone by a spider.  A locating slot in the forward edge of the cone engages a locating pin on the bomb.  The cone is secured to the bomb by four bolts, housed in the cone ring which is riveted to the inside of the cone.  The cone also has two celluloid inspection windows set into it.


Functioning: These bombs, with the exception of the No.B29 which is always nose-fuzed, are generally tail-fuzed.  When the tail-fuze magazine functions, the flash ignites the primed cambric tube in the central tube, which ignites the primed cambric washers and the candles.  The cambric tube also passes the flash to the nose burster, which explodes, ejecting the candles.  When the nose-fuzed, the flash from the nose-fuze from the burster then ignites the primed cambric tube, washers, and candles in turn.  The candles are ejected simultaneously.

 
Suspension: The bombs are equipped with a single lug for British suspension, and two lugs 180 degrees removed, for suspension in American aircraft.
  

Explosive Components: A number of combinations of candles may be incorporated in the 1000lb bomb.  The following list gives the combination used in the various bombs:

-No.B2- 200 Type A and Type D candles
-No.B4- 62 Type A, 124 Type B2, 10 Type D, and 4 Type F candles
-No.B16- 200 Type A, and Type B1 or B2 candles
 -No.B22- 140 Types A, C, D, and F candles
-No.B24- 200 Types A, C, D, and F candles
-No.B25- 12 Type A, 121 Type B3, and 9 Type E candles
-No.B26- 31 Type A, 93 Type B2, 62 Type C, 6 Type D, 4 Type F, and 4 Type P candles
-No.B28- 62 Type A, 104 Type C, 10 Type D, and 4 Type F candles
-No.B29- Red, green, yellow, or blue pigments


Remarks: This series of bombs is a larger version of the 250lb TI Bombs, with the exception of the No.B29 which has no parallel in the 250lb series.  The individual bombs within the 1000lb series, including the Bomb No.B29, differ mainly in their contents.  The Bomb No.B29 is used as a daylight skymarker.  It emits a cloud of coloured pigment which is effectively visible for about four minutes.  This bomb is called the "Skymarker Puff."










Next Time: Flares and Photoflash Bombs