Monday, 27 March 2017

British Explosive Ordnance - Hand, Rifle, and Anti-Tank Grenades







British Explosive Ordnance





Hand and Rifle Grenades Introduction


General

The various types of grenades used by the British are the anti-personnel, anti-tank, smoke, illuminating, and incendiary grenades.  The individual grenades are generally hand thrown, rifle projected, or, in some cases, may be either hand thrown or rifle projected.

The British armed forces use anti-personnel grenades of both the offensive and the defensive types.  Anti-tank grenades vary widely in principle and construction, and sometimes incorporate a cavity charge to achieve greater penetration.  Smoke grenades are of simple construction, and employ a white phosphorus charge, a burning smoke composition, or a combination of the two to produce a heavy smoke screen.  The rifle illuminating grenades consists of a basically similar series of grenades, which vary mainly as regards to filling.  The single incendiary bomb in this section is not designated as a grenade, but is included because of its similarity and use.

Grenades are commonly initiated by firing mechanisms resembling the Bouchon type igniter, by all-ways action fuzes, or by integral striker assemblies.  Special items are equipped for special initiation, such as the Grenade No.76, which is ignited by reaction of its contents, when exposed to air, or the Grenade No.75, which employs two separate chemical igniters to initiate its explosive train.


Designation

Grenades generally follow the usual British system of designation.  They are identified by a "Number", corresponding to the US Navy "Mark", and a Roman numeral "Mark", corresponding to the US Navy "Modification."  Recent issues have the mark written in Arabic numerals.


Color and Markings

Grenade bodies are usually painted a solid color to indicate their use, as follows:

Anti-Personnel ------ Black
Anti-Tank ------ Buff
Smoke ------ Green
Illuminating ------ Buff
Incendiary ------- Red

There are some departures from this listing, but it can be followed as a general rule.

A red band, generally located near the top of an H.e. grenade, indicates that the grenade is filled.  A ring of red crosses signifies that the filling is suitable for tropical storage.  The type of filling is identified by a colored band or bands around the center of the grenade body.  The abbreviation of the filling is stencilled on this band.

Each grenade has the grenade designation stamped, cast, or stencilled on the body.  In addition, the manufacturer's initial or symbol, and the month or year of manufacture are also shown.  When the grenade is filled, the initials or symbol of the filling depot,t he type of filling, date of filling, and filling lot number are stencilled on the grenade body.

In some cases, special markings may supplement or replace the standard markings.


 Firing Mechanisms

One type firing mechanisms commonly used to initiate British grenades, is similar in principle and operation to the Bouchon type igniter used in US grenades.  These striker mechanisms employ a fly-off safety lever which is retained until use by a safety pin, a pivoted, spring-loaded striker retained by the safety lever, a percussion cap, a safety fuse delay, and a detonator.  The detonator is a separate unit, which is inserted into the grenade beneath the striker mechanism shortly before using.  The several striker mechanisms which are in use differ from one another mainly in the shape of the body or safety lever, material of construction, or color of the safety lever.

The striker mechanisms used in smoke grenades filled with a smoke composition do not have a detonator.  The composition is ignited by a piece of primed cambric and priming composition, which are initiated by the delay fuse.  W.P. filled grenades employ detonators to burst the container and expose the filling to the action of the air.

Many grenades employ specialized igniters and fuzes, which are peculiar to them.


Fuze No.247

The Fuze No.247 is an "all-ways" action fuze commonly used in a number of British grenades.  The Fuze No.247 Mk I has a body which is closed at one end by a closing cap and has a flash channel at the opposite end.  A striker creep spring, cap pellet, and a lead ball are located inside the fuze body.  The striker has a concave head, into which the ball fits, and a split striker point.

The creep spring separates the striker and cap pellet.  A safety pin is inserted through the fuze body and the striker body, and has a length of fabric tape with a lead weight on the end fastened to its head.  A plastic cap fits over the fuze body to hold the tape and weight in place.

The Fuze No.247 Mk II differs from the Mk I in that it has a single point on the striker, and uses a more powerful detonator, instead of a percussion cap, in the cap pellet.  The No.III is the same as the No.II, except that the closing caps is cast in one piece with the body, and is closed instead by a plug in its base.  Different lengths of tape are used to change the arming times of the fuze.

The Fuzes Mk I and Mk II are obsolete and will not be used for future issues.

The Fuze No.247 is very sensitive when armed, and should be handled accordingly if encountered in this condition.





A/P Rifle or Hand Grenade No.36M Mk I (Obsolete)


Overall length: 4 inches
Diameter: 2.4 inches
Total weight: 1 pound, 11.25 ounces (approx.)
Delay: 4 seconds for hand grenades; 7 seconds for rifle grenades

Color: Black
Markings: Green band around center; red band or crosses around top

  
Description: This grenade consists of a lemon-shaped, cast-iron body filled with high explosive.

The body has three holes in it; one in the base for priming, one near the top for filling, and one on the top through which the striker protrudes.  The body is serrated and relatively thick, so as to give good fragmentation.  A center piece, containing a striker and spring, a primer delay train, and a detonator, is located within the body and surrounded by cast explosive.

The striker is held up and the striker spring is held cocked by a lever which fits into a slot in the top of the striker.  The lever is secured by a safety pin passing over it and through holes in two shoulders, which project on the outside of the body.  The lever is shaped with two small projections, which fit into notches in these shoulders to provide a pivot.  The lever projects down the side of the grenade body, matching the body contour.  The filling hole is closed by a screw plug.  The base plug threads into the base opening and is itself threaded to receive a 2.5-inch diameter metal gas check disc for use when the grenade is fired from the rifle projector.

The igniter consists of a primer cap, a short length of safety fuze, and a detonator.  The Igniters Mk V and Mk VI, which differs only in the composition of the safety fuze, incorporate a 4-second delay for use with hand grenades.  These igniters can be identified by the white safety fuze employed.  The Igniters Mk II and Mk III incorporate a 7-second delay for us with rifle grenades.  They can be identified by the yellow safety fuze used, and the fact that the detonator body of the Mk II is copper, while that of the Mk III is aluminum.


Operation: Priming consists of removing the base plug, inserting the igniter set, and replacing the base plug.

When the grenade is to be thrown, it is held with the throwing hand over the safety lever, and the safety pin is then removed.  When the grenade is thrown, the lever is released.  The striker spring forces the striker downward, rotating the lever about its pivot and throwing it off.  The striker hits the cap igniting the delay, which, in turn, sets off the detonator and the main filling of the grenade.

If the grenade is to be fired from a rifle discharger, it must be primed with the 7-second delay igniter and the gas check disc must be threaded tightly into the base plug.  The grenade is placed in the discharger, base first.  When the grenade is inside the discharger and the striker lever is held by the sides of the discharger, the safety pin is removed.  As the grenade is fired and leaves the discharger, the safety lever is no longer retained and flies off, allowing the striker to hit the cap.


Remarks: This grenade is packed and marked as a hand grenade with a 4-second delay igniter, or as a rifle grenade with a 7-second delay igniter.

No weight of explosive is specified, as the grenade is filled to capacity.






A/P Hand Grenade No.69 Mk I (Obsolete)
   

Overall length: 5.5 inches
Diameter: 2.375 inches
Total weight: 13 ounces
Filling: Amatol 80/20, Lyddite, or Baratol 20/80
Filling weight: 3.25 ounces
Fuze: No.247 Mk I, II, or III
Delay: None

Color: Black
Markings: The grenade has a band of red X's on the upper body, and a colored filling band around the base section.


Description: This grenade is a light, impact-firing grenade for offensive action.  The body is made of bakelite.  The area of burst is very limited, and it can, therefore, be thrown while standing in the open.  The two-piece body threads together in the middle.  There are a filling hole and plug and a priming hole and plug in the base section.  The bakelite holder for the fuze threads into a large indentation in the top section.  There is a detonator well running lengthwise through the filling.

The fuze is all-ways acting.  The striker rests on a creep spring inside a striker sleeve.  The base of the sleeve carries a primer cap.  The striker head is cut to receive a lead ball.  The closing cap is shaped so that a convex surface fits over the ball.  A safety pin passes through a hole in the fuze holder and beneath the striker head to rest on the top of the striker sleeve.  A length of tape is attached to this pin.  The tape winds around the striker holder and has a small lead weight on its free end.  A light bakelite cap threads over this whole assembly and is held securely in place by a piece of adhesive tape.


Operation: The detonator is inserted open and first into the base hole, and the base plug is replaced.  The adhesive tape is then removed and the safety cap unscrewed in one half of a turn/  After the cap is removed, the tape must be held in place by the forefinger and thumb.  When thrown, the weight on the end of the tape causes the tape to unwind and pull out the safety pin.  Only the creep spring is now holding the striker away from the primer cap.  On impact, the striker is forced into the primer cap, which initiates the detonator and explodes the grenade.


Remarks: Once the tape has unwound and the safety pin is free of the striker, the grenade is in a very sensitive condition and should be carefully disposed of.








A/P Hand Grenades No.70 Mk I (Obsolete), Mk II (Obsolete), and Mk III (Service),                and No.71 (Obsolete)
   

Overall length: 4.5 inches
Diameter: 1.75 inches
Total weight: 1 pound

Filling:
-Mk II: Baratol or Amatol
-Mk III: RDX/TNT

Fuze: No.247 Mk I, II, or III
Delay: None

Markings: Body is banded near the top in red and semibanded near the middle with two yellow bands separated by a green band.


Description: The Grenade Mk II consists of a cast-iron body, a fuze adapter, a base plug with a rubber spigot, and a filling-plug hole.  The body is cup-shaped and threaded internally at the top to accommodate a fuze adapter.  It is closed at the bottom by a threaded base plug to which is cemented a spigot.  A rubber washer is interposed between the plug and the body.  The adapter of zinc-base alloy is threaded internally to house a D.A. Percussion Fuze No.247, Mk III, and is formed with a central perforation to position an aluminum detonator tube.  A rubber washer is positioned between the fuze and the body.  The filling hole in the side of the body is closed by means of a molding plug and a rubber washer.  The body contains a filling of Baratol or Amatol.

The Grenade Mk III differs from the Mk II in that the filling hole and the thickneing of the case at that point have been completely eliminated, and the Amatol or Baratol filling has been replaced by RDX/TNT 50/50, with a C.E. pellet.


Operation: The adhesive tape securing the fuze safety cap and the cap itself are removed.  When the grenade is thrown, a weighted strip of tape withdraws the safety pin to arm the fuze.  On impact,t he striker overcomes the creep spring, and fires the cap, which initiates the detonator and, in turn, the main filling.


Remarks: The Grenade No.70 Mk I was allocated to a small number of experimental designs not issued for service use.

The Hand Grenade No.71 was a larger grenade of the same type construction as the No.70, weighing approximately two pounds.  The Grenade No.71 was never adopted for service use.











A/P Hand Grenade No.82 Mk I (Service)


Total weight: 2 pounds (approx.)
 Filling: Plastic Explosive
Filling weight: 1 pound (approx.)
Fuze: No.247 Mk I, II, or III, with short 4.5-inch tape
Delay: None

Color: Fuze, black; cup, buff; bag, black
Markings: Standard


Description: The body of this H.E. grenade, formerly known as the "Gammon Bomb", consists of a fabric bag, open at each end.  The lower end of the bag is gathered, and an elastic band inserted around the edge, while the upper end fits under a steel cup.  The edge is clamped between the cup and the flange of a tinned plate fuze housing by four equally spaced rivets.  A tin-plate cap, to the lower end of which is secured an aluminum primer tube, is screwed over the fuze housing.

The grenade is fuzed with the Fuze No.247 wound with 4 and 1/2 inches of tape instead of the usual 12 inches.  The primer tube contains a C.E. pellet over which is placed a felt washer.  A central perforation in the pellet accommodates a Detonator No.78 Mk I with a felt disc inserted between it and the bottom of the primer tube.

The grenade is issued with the bag empty.  The charge of plastic explosive is inserted through the bottom of the bag under local arrangements.


Operation: First the grenade is primed and the plastic explosive inserted.  The adhesive tape is then removed and the safety cap unscrewed in one-half of a turn.  After the cap is removed, the tape must be held in place by the forefinger and thumb.  When thrown, the weight on the end of the tape causes the tape to unwind and pull out the safety pin.  Only the creep spring is now holding the striker away from the primer cap.  On impact,t he striker is forced into the primer cap, igniting the delay, which initiates the detonator and explodes the grenade.


Remarks: The No.82 Mk I/I differs from the No.82A Mk I in that it has a rot-proof fabric bag.

This grenade has a general anti-personnel application, but is used mainly by airborne force as an anti-tank weapon.










Anti-Tank Grenades




A/T Rifle Grenade No.68 Mks I-VI (Obsolete)
   

Overall length: 7 inches
Diameter: 2.5 inches
Total weight: 1 pound, 15.5 ounces
Filling: RDX/BWX 91/9, P.S., Lyddite, C.E/TNT 30/70 or Pentolite
Filling weight: 5.5 ounces
Delay: None

Color: Buff
Markings: Red filling band around top and green band around center of body.


Description: The grenade consists of a steel or Mazak bell-shaped body fitted with a tail.  The open end of the body is fitted with a  thin metal cavity liner, which forms a hollow in the H.E. fitting.  The cup is secured by a screw collar.  The dome of the body is bored to carry the detonator holder and threaded to receive the tail section.  The tail has four straight vanes and is centrally recessed to receive the striker.  A copper shear wire and safety pin secure the striker in position.  The pin is removed before the grenade is fired.  The gas check plates are secured either by metal rivts, or in an integral casting with the fins of the grenade.

The following differences exist among the carious marks of this grenade.  The Grenade Mk I has small tail vanes and an additional small set of vanes on the body.  A steel gas check is secured to the tail by a bakelite or brass screw.  The brass cavity liner is hemispherical in shape.

In the Grenade Mk II the small vanes were removed from the body and the tail vane enlarged.  The gas check was secured by a brass screw or by crimping the tail.  In the Mk III a cylindro-conoidal steel cavity liner was substituted for the hemispherical liner previously used.  The gas check was either secured by crimping, or was made of Mazak cast integrally with the tail unit.  The Grenade Mk IV employed a new type of detonator holder, and had the tail unit and gas check cast integrally of Mazak.  The Grenade Mk V also employed the new detonator holde,r but used the steel gas check secured by crimping.

The Mk VI was produced in the United States.  The tail unit consisted of a steel tail tube to which the tail fins were spot welded.  A wooden plug, secured by a shoe rivet, closed the after end of the tail tube.

Operation: Before the grenade is fired from the discharger, the safety pin must be removed.  The striker is located slightly away from the rear of the tube containing it.  On setback, the striker moves to the rear, shearing the shear wire.  It is then held only by the creep spring.  On impact, the striker overcomes the creep spring and hits the detonator to explode the grenade.  The effective range is given as 50 to 75 yards.







A/T Hand Grenade No.73 Mk I (Obsolete)
   

Overall length: 9.5 inches
Diameter: 3.25 inches
Total weight: 4 pounds
Filling: Polar ammon gelatine dynamite
Filling weight: 3.25 pounds
Fuzing: No.247 Mk I, II, or IIII
Delay: None

Color: Buff
Markings: Red filling ring around the upper body and standard markings.

  
Description: This is a thin-walled grenade intended for use against armored forces vehicles, but more generally used in demolition work.  The grenade consists of a tin-plate container with a top of the same material, which screws onto the body by means of interrupted threads.  A recess in the middle of the lid is threaded to take the Fuze No.247.  The fuze is cemented in position and issued with the grenade.  The detonator tube screws into the lower portion of the fuze housing.  A commercial Detonator No.8 is used.  A felt disc at the top of the filling absorbs any exudate from the explosive.  A strip of adhesive tape secures the lid to the body on issue.

Operation: Before use, remove the adhesive tape, take off the lid, and unscrew the detonator holder.  Insert the detonator, and replace the holder and lid.  Then remove the adhesive tape from the fuze and unscrew the fuze cap.  After the cap is removed, the safety tape must be held in place by the thumb and forefinger.  When thrown, the weight on the end of the tape causes the tape to unwind and pull out the safety pin.  Only the creep spring now separates the striker and primer cap.  On impact,t he striker is forced into the primer cap, which initiates the detonator and explodes the grenade.








A/T Hand Grenade No.74 Mks I and II (Obsolete)
   
   
Overall length: 9 inches
Diameter: 4.5 inches
Total weight: 2.25 pounds
Filling: Nobel's No.823 explosive
Filling weight: 1.25 pounds
Delay: None

Color: Body, buff; handle, black
Markings: Red filling band around the upper body.


Description: The Grenade No.74 Mk II consists of a globular bakelite flask containing the explosive filling, which is primarily nitro-glycerine and nitro-cellulose, a bakelite handle containing the firing mechanism, and an adhesive-treated sock.  During filling, an air space is left to allow for expansion of the explosive.  The sock covers the flask and is very sticky.  The handle threads directly into the flask.  Within the handle is a sharp striker and a striker spring.  A safety lever fits under a nut on the head of the striker and down the handle to hold the striker up and the spring compressed.  The top of the striker is spread to retain the nut.  A safety pin passes through holes in projections on the safety lever, through the handle, and under the striker.  The flask is closed at the neck by an externally threaded safety plug into which the detonator assembly is inserted immediately before use.  The detonator assembly consists of a percussion cap, a 5-second delay, a detonator, and a C.E. pellet.

A light metal container, made in two hemispherical sections joined by a spring hinge, clamps over the sticky flask for protection during handling and shipping.  Before the grenade is used, this cover must be removed by releasing the spring clip at the neck of the case.  Several small rubber projections on the inside of the case separate it from the adhesive sock.

The detonator assembly is placed into the well in the flask.  The handle is then screwed into the neck of the grenade and the casing removed.  The handle must be grasped firmly with the hand over the safety lever before the safety pin is withdrawn.  After the safety pin is removed, the handle is released and the striker spring forces the striker down, throwing off the safety lever and striking the percussion cap.

This grenade has been designed for use against armored-force vehicles.  It is supposed to stick to the target, but will not adhere to a sloping surface, should it be wet, muddy, or oily.  Although it can be thrown for short distances, far better effect will be obtained if the grenade is placed directly on the target with enough force to break the flask.

The viscous explosive filling tends to run at moderate temperatures; thus storage temperatures must be kept low.  The grenades are definitely subject to sympathetic detonation.


Remarks: The Grenade No.74 Mk I is similar to the Mk II in operation, but differs in several constructional details.  The Mk I had a glass flask which proved to be too fragile and was replaced by bakelite in the Mk II.  The Mk I was filled to capacity with explosive and consequently leaked if expansion took place.  The handle was fastened o the body by a plastic retaining ring which gave too weak a joint.  The blunt striker was a frequent cause of misfires.  The Mk I and II also employ slightly different detonator assemblies.







A/T Hand Grenade No.75 Mks I, II, and III (Service)
   


Overall length: 6.5 inches
Width: 3 and 5/8 inches
Height: 1 and 7/8 inches
Total weight: 2.25 pounds
Filling: Nobel's No.704B, Ammonal, Burrowite, or TNT (all with exploders or C.E. pellets)
 Filling weight: 1.75 pounds

Fuze:
-Mk I: Grenade Igniter No.75 Mk II
-Mk II and III: Detonator No.83

Delay: None
Pressure to fire: 300 pounds

Color: Buff
Markings: Cap painted pink when Burrowite or Ammonal filled; red filling ring below cap indicates Victor Powder or Exp. No.673 exploder; ring of red crosses indicates Polor Dynamite exploders.


Description: The Grenade Mk I consists of a 1-pint capacity, flat, tin-plate can, which is rectangular in shape, and has rounded corners.  It is filled through a hole in the end, over which a tin cap is screwed and cemented to provide watertightness.  On one side of the can are two metal pockets with slots cut in them, which form the detonator holders.  These pockets have malleable metal tabs which are bent to close them.  The striker plate is supported above the detonator holders by two brackets, one on each end of the can.  The striker plate is a light metal plate with a transverse projection on the bottom which serves as a striker.  It is secured to the brackets by two bent tabs, so that the striker is immediately over the slots in the detonator holders.  The principal differences between the Grenades Mk I and Mk II lie in the fuze pockets, which in the Mk II are set at an angle for easier insertion of the fuze assemblies, and in the detonator assemblies.  The Grenade Mk III is similar to the Mk II, but has no filling cap.  It is filled with 1.75 pounds of TNT, and two C.E. pellets.

The fuze for the Grenade No.75 Mk I consists of an Igniter No.75 Mk II and a detonator.  Two of these units are used with each grenade.  The igniter is a tin-plate tube closed at one end by flattening, and it is painted red.  It contains an acid-filled glass ampoule, and ignition composition.  A rubber tube is roleld into the igniter.  The detonator is an aluminum tube open at one end, and is smaller in diameter than the igniter.  The detonator is slipped into the open end of the igniter, and the rubber tube rolled over the joint to provide waterproofing.

In the Grenades Mk II and Mk III, the detonator units are manufactured and issued in one piece.  Each Detonator No.83 consists of a bakelite holder containing a glass ampoule, the end of which is sealed with wax.  A striker pin is held in the top of the holder by means of a red cellulose seal.  The detonator fits tightly over a tubular projection on the holder, and is sealed on with glue.  As with the Grenade Mk I, two assemblies are provided with each mine.  Pressure on the plate forces the striker pins into the ampoules, which fire the detonators and thus the main charge.  The Grenade Mk II uses the C.E. filled Detonator No.83 Mk I, while the Mk III grenade uses the RDK filled Detonator No.83 Mk II, which is also designated No.96 Mk I.

The grenade is so shaped that when thrown it will come to rest with the striker plate either on top of underneath.  It will operate equally well in either position.




Operation: For the Grenade No.75 Mk I, insert the open end of the detonator into the open end of the igniter.  Then roll the rubber tube on the igniter to cover the joint.  This provides a water-tight seal.  Insert a detonator assembly, detonator end first, into each of the pockets of the detonator holder through the hole in the striker-plate bracket.  Bend over the metal tabs, thus securing the detonator assemblies int he pockets.  The red painted portions of the assemblies should now be visible in the slots of the detonator holders.  The grenade is thrown or placed so that it will be run over.  The pressure of the vehicle upon the striker plate will force the strikers through the slots in the detonator holders, crush the igniter tubes, and break the glass capsules containing nitric and sulphuric acid.  The action of the acid on the potassium chlorate and charcoal ignition composition produces an immediate flash, which sets off the detonators and explodes the grenade.

In the Grenades No.75 Mk II and Mk III, the igniters are inserted in their pockets and the tabs bent into place to secure them.  When the grenade is run over,t he striker pin crushes the glass ampoule and grins the broken glass and contained igniter composition together, igniting the composition.  The resultant flash initiates the detonator, which explodes the grenade.


Remarks: When the Grenade No.75 is filled with Ammonal, the designation is changed to No.75A. Ammonal is about 80% as powerful as the regular fillings.

The Grenade No.75 is actually employed mainly as a land mine for defense against armored cars, tanks, and other vehicles.  It will disable light tanks and vehicles and is used principally for hasty minefields.

The Grenade No.75 is often referred to as the "Hawkins" grenade.









A/T Rifle Grenade No.85 Mks I, II, and III (Soon in Service)
   

Overall length: 10.5 inches
Diameter: 1 and 7/8 inches
Total weight: 1 pound, 6 ounces
Filling: RDX/TNT 50/50
Filling weight: 4.5 ounces
Fuzing: No.430 Mk I and No.431 Mk I
Delay: None


Description: The Grenade No.85 is an anti-tank, cavity-charge grenade patterned after the US Army M9A1 and similar in construction.  The Mk I is fitted with Fuze No.430 Mk I, which will function satisfactorily on impact up to 45 degrees from the normal.  There is no safety pin to withdraw, and the fuze does not arm until the grenade is fired.  The Grenade Mk II has the same head but is fitted with t he Fuze No.431 Mk I, which differs from the Fuze No.430 in that it has a longer booster, and is easier to assemble and inspect.

The Grenade No.85 Mk III is similar to the Mk I except for the fact that the lower body is wire wrapped to increase fragmentation, allowing a dual employment as either an anti-tank or anti-personnel grenade.  The tail tube and fuze are made of a light alloy in the Grenade Mk III.  This change of material gives the fuze the designation No.431 Mk I/L.


Operation: Upon firing, the diaphragm is reversed by gas pressure, forcing the arming spindle forward.  This permits the locking ball to slip into the groove in the arming spindle, thus freeing the striker, which is held away from the cap by the creep spring.  Upon impact, the striker compresses the creep spring to fire the cap, the booster,a nd the main filling.






Next Time: Smoke, Illuminating, and Incendiary Grenades, and Anti-Tank Mines

Sunday, 19 March 2017

British Explosive Ordnance - Rocket Flares, Wire-Barrage and Pyrotechnic Rockets







British Explosive Ordnance





 Rocket Flares Introduction


This chapter is concerned with rocket assemblies which carry an illuminating candle.  A parachute may suspend the flare candle for purposes of illumination after ejection, as in the case of the 2-inch and 3-inch rocket flares, or the candle may not be either ejected or supported by a parachute, as in the case of the 2-inch target rocket, which merely furnishes a moving, visible target for anti-aircraft practice.

The section of the rocket flare containing the candle, parachute (if present), and initiating device, is called the flare head.  It corresponds to the "shell" in H.E. rockets.  The heads of the rocket flares discussed in this chapter are attached to the rocket motor by the conventional shell ring.






2-in UP Rocket Flare (Service)



Flare Head
Overall length: 22 inches (approx.)
Diameter: 2.25 inches
Total weight: 4.75 pounds
Fuzes used: Thermal Initiator


Rocket Motor:
Overall length: 31 inches (approx.)
Diameter: 2.25 inches
Width of fins: 2.375 inches
Total weight: 7.5 pounds
Propellant: Tubular cordite
Propellant weight: 2.5 pounds
Burning time at 60 degrees Fahrenheit: 0.9 seconds

  
General: This flare is used to illuminate enemy targets at night.  It is used in conjunction with medium-caliber guns.  A flare launcher is mounted on either side of the gun shield at a fixed angle of 30 degrees.  This arrangement makes it possible to keep a target illuminated and at the same time engage it with the main armament.


Description

Rocket Flare Head, 2-inch, No.1 Mks I and II, No.2 Mk I, and No.3 Mk I: The flare head consists of a cylindrical tinned-plate container, with two cannelures near the base.  Inserted in the container is a metal canister, which houses the illuminating candle and attached parachute assembly.  A ballistic cap is fitted to the forward end of the container, to which is secured with adhesive tape.  A base socket is secured to the other end of the container by indenting the cannelures.  The base socket screws into the shell ring of the rocket motor and contains the thermal ejector.  This latter consists of a steel base plate, in the center of which is a metal septum of accurately machined thickness.  The lower end of a length of safety fuze (primary delay), cut to burn approximately 22 seconds, makes contact with 2 and 1/2 grains of lead-dinitroresorcinate (LDNR), which is stemmed into the septum recess.  The upper end of the safety fuze extends into a magazine containing about 40 grains of G.12 gunpowder (primary ejection charge).  Protruding from the base end of the canister is a short length of safety fuze (secondary delay) cut to burn for 3 seconds.  The proximity to the primary ejection charge, and its upper end projects into a magazine containing about 40 grains of G.12 gunpowder (secondary ejection charge).

The different flare heads vary only in the contents ejector employed, as follows: Flare Head No.1 Mk I uses Ejector, Contents No.4 Mk I (with 22-sec delay); Flare Head No.1 Mk II uses Ejector, Contents, No.4 Mk II (with 18-sec delay); Flare Head No.2 Mk I uses Ejector, Contents, No.5 Mk I (with 9-sec delay); and Flare Head No.3 Mk I uses Ejector, Contents, No.8 Mk I.







Tail, Propelling, Rocket, 2-inch, Mks VI and VII: The Motor Mk VI is identical to the 2-inch Motor Mk III, except that the obturator of the latter is perforated, while that of the former is not, but rather is rust-proofed to allow free conduction of heat to the thermal fuze in the flare head.  For this reason, Motors Mk VI are marked T.I., indicating their use with thermal initiators.  No other motor may be used with the flare head.

The Motor Mk VII differs from the Mk VI in that the castellations in the charge are omitted and a metal cased cylindrical igniter is employed.


Operation: When the rocket is fired, heat from the burning propellant grain is transmitted through the head obturator and the thin septum of the thermal ejector, igniting the LDNR and initiating the lower end of the primary delay.  After a set delay, the primary ejection charge is ignited, and the canister is ejected from the container in a forward direction.  The secondary delay is initiated by the flash from the primary ejection charge, and, after three seconds, initiates the secondary ejection charge, which ignites the candle and ejects the parachute, cable, and candle in a forward direction from the canister.  The parachute opens when ejected from the canister, and the lighted flare candle is suspended in mid-air.

The purpose of the secondary delay is to allow the velocity of the canister to be reduced to a speed at which the flare and parachute assembly may be ejected without danger of break-up.

The flare is ejected at a range of about 5,000 yards and an altitude of about 2,000 feet.  The duration of burning of the flare is about 70 seconds.


Remarks: This flare, fitted with 4-inch by 1-inch fins, may be fired from a spiral launcher to obtain greater accuracy. 

The complete round (flare head and motor) weighs 12.25 pounds and measures 51 inches in overall length.






2-in UP Target Rocket (Service)
   


Target Head

Overall length: 15.75 inches
Diameter: 2.25 inches
Total weight: 4.5 pounds
Fuzing: Special igniter

  

Rocket Motor

Overall length: 20.25 inches
Diameter: 2.25inches
Width of fins: 2.375 inches
Total weight: 6 pounds
Propellant: Cogged cordite
Propellant weight: 1.25 pounds
Burning time: 0.45 seconds


  
General: This rocket is designed to give, by means of an integral flare, a visible aiming mark for anti-aircraft batteries.  The target has a range of about 5,000 yards at a speed of 250 to 400 knots.  The target can be used at night and is suitable for use from either aboard ship or ashore.





Description

Head, Rocket Target, 2-inch, Mk I: The target head consists of a thin sheet-metal container holding a flare candle.  Separated from the flare candle by a steel washer is an externally threaded spigot, by which the head is attached to the shell ring of the rocket motor.  The spigot is fixed to the target head body by means of a double crimp.  A weight is fitted into the forward end of the body and is fixed to the body by four screws.  A ballistic cap is crimped to the forward end of the weight.

Four holes are drilled through the body and the weight just before the flare candle, and a similar set of four holes is drilled abaft the candle through the body and the spigot.  The two sets of holes are covered with a strip of tape 1.5 inches wide, which is wrapped around the body.

An igniter mechanism, consisting of a diaphragm-operated striker, a percussion cap, and a gunpowder charge, is inserted into the after end of the spigot and is held in place by a threaded locking ring.






Tail, Propelling, Rocket Target, Mk I: This motor consists of a cylindrical steel body with a shell ring fixed in the forward end by eight locking pins held in engagement by a circular band spring.  Separated from the shell ring by a steel, flanged support ring, is an igniter in a cylindrical metal container.  Leads from the igniter extend through the central annulus of the cogged cordite grain to four automatic contacts fixed 45 degrees apart on the after end of the motor body.  A metal grid supports the cordite grain near the after end of the motor, and a thin metal obturator separates the grid from the venturi.  A bag of silica gel is placed in the venturi as a moisture-proofing measure.

This rocket motor must not be fired outside the temperature range of -5 to 130 degrees Fahrenheit.  Proposed new nomenclature for this motor is Motor, Rocket, 2-inch, No.4 Mk I.



Operation: Pressure of the gases from the burning cordite propellant grain passes forward into the spigot of the target head, reversing the diaphragm of the igniter.  This forces the striker into the percussion cap and ignites the gunpowder charge, which in turn initiates the flare composition.  The flare composition burns brightly, emitting light from the two sets of holes drilled in the body of the target head.









3-in Aircraft Rocket Flare (Service)
   


Flare Head
Overall length: 22.5 inches
Diameter: 5.45 inches
Total weight: 14.7 pounds
Candle power: 1,000,000
Burning time: 70 seconds
Time to primary ejection: 16 seconds
Time to light up: 19 seconds

Range to light up:
-4,800 yards when fired from ground
-5,600 yards when fire from aircraft at 140 knots



General: This head is designed for use with 3-inch A/C Rocket Motors, and may be fired either from aircraft or from ground launchers.
  


Description: The 3-inch A/C Flare Head Mk I consists of an outer body assembly and an inner canister.  The inner canister is brought to an ogive at its forward end to serve as a ballistic cap.  A parachute, enclosed in a cardboard housing, is contained in the upper portion of the inner canister.  The long cylindrical portion of the canister is then brought down inside the main body assembly, and tabs on the bottom edge of the canister are then bent over a metal lid, retaining the lid in position.  The lid consists of a metal disc, perforated in the center to accommodate the ends of two lengths of safety fuze.  A baffle plate is located between the lid and the flare candle.  Lengths of quickmatch extend from the base of the candle through the center of the baffle plate and into a gunpowder charge located between the baffle plate and the metal lid.  This charge constitutes the secondary ejection charge.  The safety fuze leading to it is the secondary delay.

A socket is fixed to the lower part of the body assembly, and to the socket is welded a spigot.  The spigot is threaded externally to screw into the shell ring of the rocket motor, and is internally threaded to receive the Ejector, Contents, No.7 Mk I.  The contents ejector consists of a threaded body, housing a diaphragm-operated striker, a percussion cap, and a double length of safety fuze, which extends into a gunpowder charge.

A base fairing is loosely assembled over the lower portion of the body assembly.  The after end of the fairing is notched to form several tabs, and a metal clip is placed around these tabs and tightened to ensure a firm attachment to the rocket motor.  The fairing serves merely to cover the joint between the flare head and the rocket motor, enhancing the streamlining of the complete round.



Operation: The pressure of the propellant gases from the rocket motor reverses the diaphragm of the contents ejector, thus firing the cap and the safety fuze in the ejector.  After the expiration of this primary delay (16 seconds)_ the primary gunpowder ejector charge is fired, expelling the inner container from the flare body assembly.  The explosion of the primary charge also ignites the secondary delay.

When the secondary delay expires, the secondary ejection charge is initiated, which ignites the lengths of quickmatch beneath the flare candle, and blows the lid out of the after end of the inner container, bending back the tabs on the base of the container.

The flare candle and the parachute assembly are now free the fall out of the after end of the container.  The flare has been ignited by the flash from the lengths of quickmatch, and is suspended in mid-air by the open parachute.  The purpose of the primary delay and ejection charge is to allow the flare ample time to lose velocity sufficiently so that an undue strain will not be placed on the parachute.

The flare head is painted black overall with a 1/2-inch red band painted around the flare body near the base.


Remarks: This flare head may be employed with the following motors: Motor, Rocket, A/C, 3-inch (Rocket Flare) Mk I; Motor, Rocket, A/C, 3-inch No.1 Mk I; or Motor, Rocket, A/C, 3-inch, No.1 Mks II-IV.









Wire-Barrage Rockets Introduction


This chapter deals with four rockets, which are designed to erect a vertical barrage consisting of parachute-supported cables, or parachute-supported wires carrying H.E. bombs.  These devices provide a temporary lethal deterrent to planes employing low-level attacks or dive-bombing tactics, and are supposed either to destroy or damage the attacking planes, or to cause them to abandon the attack.





Apparatus A.D. Type B Mk I (Obsolescent)
   

Overall length: 37 inches
Diameter: 7 inches
Total weight: 37 pounds
Propellant: Tubular cordite
Propellant weight: 3.9 pounds
Charge igniter: Magnesium (S.R. 371)
Separating charge: 154 grains G.12 gunpowder
Mine wire: 1,000 feet of steel piano wire
Bomb: H.E., A.A.D., No.2 Mk I
Bomb weight: 1 pound
Explosive: C.E. (tetryl)
Explosive weight: 8 ounces




  
General: This rocket is employed to lay a curtain of aerial mines in the path of low-level or dive-bombing aircraft attacking a ship.





Description: The tail of the rocket consists of a center tube containing the propellant charge, the gases from which emerge through the venture to propel the projectile.  The propulsive force continues for about 1.5 seconds.  Around the center tube is fitted a fairing to which are attached tail fins, protected by a cylindrical shroud.  The electric igniter leads pass through the tail fins, enter the center body of the rocket, and lead to the electric igniter.  Connected in parallel to the igniter is an electrically fired time fuze, which burns through the ignite the separating charge.  The separating charge is fired after about 10 seconds of flight time, and ejects the contents of the rocket head, which consist of the bomb, the mine wire, and the parachutes.

Operation: When the separating charge is ignited, the outer container is ejected forward from the outer case by the pressure of the exploding charge against the pressure plate.  As soon as the outer container is clear of the outer case, the pressure plate and the lid fall clear.  The lid acts as a pilot parachute and withdraws the main parachute from the container.  The main parachute opens, and, since it is connected by a spring shock absorber to the inner container, it pulls the latter clear of the outer container, which continues to fall, paying out the coiled mine wire inside it as it falls.

Also attached to the outer container is a cord, which pulls out the arming wire of the bomb as the two containers separate.  This cord subsequently breaks away to clear the wire which is being paid out.  The upper end of the mine wire is attached to the bomb and jerks it clear of the retaining-spring clip in the inner container.  The bomb is then suspended from the shock absorber by a length of light cord, termed the weak link.  This cord is secured to the shock absorber at one end, and at the other to a length of heavy cord leading from the bomb to the 7 and 1/2-inch parachute carried in the inner container. The heavy cord is thus slack between the knot and the parachute.

When all the mine wire has been paid out, the bottom bundle, containing the 30-inch parachute, is withdrawn from the outer container.  The canvas bands which protect the bundle on its way out of the container are then pulled clear by the release cord, and the bottom bundle is left hanging from the wire.  This state is accomplished about eight seconds after separation of the outer container from the rocket.

When the mine wire is struck by an aircraft, the weak link between the bomb and the shock absorber breaks, and the 7 and 1/2-inch parachute is pulled clear of the inner container and springs open.  The tautening of the wire also rips the bag of the bottom bundle, and the bottom 30-inch parachute opens.  As the aircraft pushes the wire along, the bottom parachute acts as a drogue and drags the wire across the aircraft, pulling the bomb down into contact with it.

The Bomb No.2 Mk I consists of a light sheet-steel case filled with explosive and containing a striker, detonator, and self-destroying assembly.  When the arming pin is withdrawn, the detonator is forced by its spring into alignment with the striker.  Simultaneously the delay firing pin on the detonator carrier strikes the cap and a length of safety fuze is ignited.  When the bomb strikes the aircraft, the striker is forced in and fires the detonator, exploding the bomb instantaneously.  If the wire is not struck by the aircraft, the safety fuze will burn through and detonate the bomb after about 95 seconds.  Thus the bomb is self-destructive after about 1,250 feet of fall.


Remarks: The round should ne be subjected to temperatures in excess of 110 degrees Fahrenheit.









Apparatus A.D. Type D Mk III (Service)
   

Overall length: 34.25 inches
Maximum diameter: 3.45 inches
Time to eject: 5 seconds
Lethal period: 7 seconds
Visible deterrent: 12 seconds

  
General: This rocket is designed to erect lethal wires vertically over a ship in the path of low-level or dive-bombing aircraft.  The wire is carried into the air by a rocket and is suspended by a parachute, which is carried in a container in the head of the rocket motor.  A parachute on the lower end of the wire opens when a plane strikes the wire and offers sufficient resistance to throw the aircraft momentarily out of control or to cause it to break up.  The apparatus remains lethal until its lower parachute strikes the water, about 7 seconds after ejection of the upper parachute.  It continues to act as a visible deterrent for an additional 5 seconds by which time the upper parachute has fallen to an ineffective height.




Description: The rocket consists of a tube filled with rocket-propelling composition having a conical hole down the center.  This hole is aligned with that in a choke in the after end of the tube.  A length of quickmatch and a gunpowder burster charge are located in the forward end of the tube immediately below the parachute container.  The parachute container holds the folded parachute and is closed at the forward end by a metal cap.  The parachute is connected to the forward end of the rocket motor tube.

A steel bridle and a cable are attached to the motor tube.  The cable is fitted with a loop for attachment to the main cable from the lower canister.

The lower canister consists of a cylindrical or rectangular box, which contains about 400 feet of cable.  To the lower end of the cable is attached a 38-inch drag parachute.  The forward end of the cable is attached to the cable leading from the bridle on the rocket motor.

Operation: When the projector, loaded with rocket and cartridge, is fired, the flash from the cartridge ignites the rocket propellant composition, which propels the rocket along its trajectory.  As the rocket rises, it uncoils and carries with it the main cable from the lower container, which remains fixed to the rocket projector.  When the cable is completely uncoiled, it withdraws the drag parachute from the container.  This parachute is fitted with an explosive link arrangement, allowing the parachute to open 3 seconds after firing.

When the propellant composition is completely burned out, the length of quickmatch in the head of the tube is ignited and in turn initiates the gunpowder burster charge.  This charge ejects the upper parachute from its container, leaving the rocket tube and the wire cable suspended in the air.

When an aircraft strikes the wire, the lower parachute opens and offers sufficient resistance to throw the plane out of control or to cause it to break up.








Apparatus A.D. Type J Mks I, IA, and II (Service)
   

  
General: This rocket is designed to erect a lethal wire vertically over a ship in the path of low-level or dive-bombing aircraft.  The wire acts both to bring down the aircraft if it strikes the wire, and as a visible deterrent to force the aircraft to abandon the attack.





Description: The head canister is a light cylindrical metal container, into which is packed a 62-inch parachute, called the top parachute, the cords of which are firmly secured to the base of the head canister.  A thermal fuze is fitted into the head canister and consists of a pellet of LDNR, a length of safety fuze, and 100 grains of G.12 gunpowder, which acts as an ejection charge.

The Tails, Propelling, 2-inch, Mks IVA and VA are standard 2-inch rocket motors, with a rigid stirrup welded to their after end.  No fins are fitted to the motor.  Contained within the motor body is a tubular cordite grain, into the head of which is fitted an electrical igniter.  The after end of the motor is sealed off by a light metal closing disc, through which pass the ends of the igniter leads terminating in a two-pin plug.  The proposed new nomenclature for the rocket motors is Motor, Rocket, 2-inch, No.2 Mks I and II.

The main container is a cylindrical-shaped metal container about 14 inches in diameter, with a removable lid.  Inside the container are two smaller concentric tubes, the outer of which is cone-shaped, while the inner is cylindrical.  Also encased within the main container are 825 feet of wire, a fabric bag into which is packed a 62-inch diameter parachute called the lower parachute, and a 20-inch diameter parachute called the trail parachute.

The wire is coiled down between the cone-shaped cylinder and the main container, and swivels are attached to the top and bottom ends of the wire.  The bottom swivel is shackled to the ring at the foot of the cords of the lower parachute, with the ring just protruding through the fabric bag.  Cords which keep the bag closed are connected to the trail parachute by a weak cord connection and a rip cord.  The trail parachute and fabric bag are packed into the small central cylinder, and have the swivel passing through a special slot.  The cylinder is then sealed with a light metal lid.







Operation: The rocket is fired when the attacking plane is within about 800 yards of the ship.  The wire is fully run out of 3.5 seconds after firing, and pulls the lower parachute bundle and the trail parachute up out of the inner cylinder, the lid of which is ripped off by the bottom swivel as it is pulled up.  Meanwhile, the heat from the burning cordite grain ignites the LDNR pellet in the thermal fuze, and this in turn ignites the safety fuze.  The safety fuze burns for about 6.5 seconds and then initiates the gunpowder ejection charge, blowing off the top part of the head canister and allowing the top parachute to open.  This occurs at an altitude of about 1,100 feet.  The lower parachute, still wrapped in its bag, is suspended at the bottom of the wire, and the trail parachute, which is now open, is attached to the bundle by the weak cord connection and the rip cord. 

After the top parachute opens, the wire begins to fall at about 42 ft/sec.  Twelve seconds after firing, the bottom parachute enters the water.  As soon as this occurs, the wire ceases to be lethal, but it remains a visible deterrent for an additional 12 seconds, by which time the top parachute has fallen to an ineffective height.

If the plane strikes the wire during its lethal stages, the pull on the wire breaks the weak cord connection between the lower parachute and the trail parachute.  This allows the trail parachute to pull the rip cord on the bundle, opening the fabric bag and freeing the lower parachute.  The sudden jerk caused by the wind operating on the lower and top parachutes is sufficient to throw the plane momentarily out of control, or in some cases to cause it to break up.


Remarks: The round must not be fired outside of the temperature range of 0 to 120 degrees Fahrenheit, except motors marked "S.U./K." which may be fired within the range of -5 to 130 degrees Fahrenheit.

The Apparatus Mk I differs from the Mk II in that the ceiling height of the rocket is 800 feet, and the wire is only 600 feet long.







Apparatus A.D. Type L Mks I, IA, II, and IIA (Service)
   


Canister length: 32.7 inches (approx.)
Canister diameter: 6.8 inches
Motor length: 31 inches (approx.)
Motor diameter: 2.25 inches


Use: The purpose of the Type L apparatus is to lay a curtain of aerial mines in the path of low-level or dive-bombing aircraft.





Description: The Canister Mk I consists of a conical upper container, which is connected to the tail of a 2-inch rocket motor by a short rod and a stirrup.  In the upper container are a parachute to bring down the spent motor, etc., the main support parachute, a bomb steady parachute, and the bomb.  These items are all held in position by three retaining cords, which are controlled by an explosive link.

The swivel on the lower end of the bomb is connected to the top end of a 1,000 foot coil of steel piano wire, which is contained in the lower container.  The wire from the bomb passes to the top of the coil through a slot cut in the central tube.  The central tube is provided to aid in unspooling the wire and avoid failures due to kinking.  The lower end of the 1,000 foot coil of wire passes back through the slot in the central tube and is connected to a long, light shock absorber, whose lower end is attached to the drag parachute assembly.  This latter consists of a 32-inch drag parachute housed in a bag and prevented from opening on the initial jerk at pick-up by four retaining cords controlled by an explosive link.  The junction between the upper and lower containers is effected by crimping parts of the base of the upper container lightly over the top of the lower container.

The electric leads for igniting the electric delay fuzes extend from the base of the lower container and terminate in a two-pinned plug which fits into a socket on the projector.

The Bomb, H.E., A.A.D., No.8 Mk I consists of a light sheet-steel cylinder filled with explosive.  A detonator is held in a shutter which is normally kept out of alignment with the striker by a clock spring.  An arming vane is attached to the outside of the bomb casing, and this vane, by means of a pinion wheel, is enabled to move the shutter sufficiently to align the detonator with the striker.

The Tail, Propelling, 2-inch, Mks IVB and VB consists of a slightly modified 2-inch standard rocket motor.  A closing plug is placed in the shell ring, and the electric leads terminate in a two-pin plug, which engages a socket on the projector.  The propelling unit is connected to the canister assembly by a 12-inch steel stirrup and a steel connecting rod 18 inches long.  A quick-fastening bolt is provided in the top of the canister for rapid connection to the connecting rod.  The proposed new nomenclature for the motor is Motor, Rocket, 2-inch, No.3 Mks I and II.





Operation: When the projector switch is closed, the rocket itself and the delay fuzes on the upper and lower explosive links are ignited simultaneously.  The rocket motor tows the top container into the air, and the wire is unspooled from the lower container, which remains fixed on the projector.  At the end of unspooling, the drag parachute assembly is picked up, the snatch tension being kept within safe limits by the long shock absorber.  The upper and lower explosive links are timed to operate when the container has reached a height of about 2,000 feet.

On operation of the explosive link in the top container, the bomb and parachutes are released and pulled out of the container.  Ejection of the rocket-support parachute is facilitated by a very weak cord connection between the rocket-support parachute and the main parachute.  The operation of the lower explosive link removes the constraint from the drag parachute and leaves the parachute free to open when a plane makes contact with the wire.

When a plane hits the wire, the drag parachute opens, and the weak link securing the 6-foot support parachute will part.  The bomb is pulled downwards onto the wing of the plane by the drag parachute.  When the bomb strikes the aircraft, the striker is forced downwards by the universal striker ring, firing the detonator.


Remarks: This rocket should not be fired outside of the temperature range of 0-120 degrees Fahrenheit.

The Mk II canister is identical to the Mk I except that no shock absorber is fitted, one side of the slot in the central tube is slightly flared to assist unspooling, and the length of the piano wire coil is 1,500 feet instead of 1,000 feet.











Pyrotechnic Rockets Introduction


Pyrotechnic rockets are relatively small pyrotechnic items, similar in principle to the familiar sky-rocket, which are used mainly for signaling, line-carrying, and illumination.  In most cases they are fired from a hand projector.

These items generally use a type of construction in which the head and rocket tube are integral The rocket tube is filled with a propellant composition having a tapered, conical vent hole in its center to facilitate burning.  The after end of the tube is constricted, or contains a plug of narrower diameter than the rest of the tube in order to concentrate the expanding propellant gases.  The choke and a short length of the vent tube interior are coated with gunpowder to assist in ignition of the propellant.



Kite-Launching Rocket Mk II (Service)
   

Overall length: 10.25 inches
Maximum diameter: 1.25 inches


  
General: These rockets are used to enable kites to be raised easily from emergency dinghies.  They are fired from a 1-inch signal pistol fitted with a barrel extension.
  


Description: The main rocket propellant composition is contained in the case, the nose of which is closed by a wooden plug and a layer of clay.  The after end of the case houses a plaster-of-paris choke, which is covered by a millboard washer and a paper disc.  A conical vent in the rocket propellant is aligned with a hole through the choke.  The end of the vent nearest the choke is coated with gunpowder priming.

The rocket is fixed in a bridle having a hinged stirrup, to which is attached a 2-foot wire cable.  During flight, the cable end nearest the rocket is protected from heat by an asbestos sheath.  The free end of the cable carries a loop for connection with the kite tow-line.

The rocket is painted aluminum overall, with manufacturing and filling information stencilled on the case in black letters.


Operation: When the pistol, loaded with rocket and cartridge, is fired, the flash from the cartridge ignites the gunpowder priming in the rocket, and the priming ignites the rocket propellant composition.  The rocket travels upwards for a distance of about 200 feet until the kite flying line is almost paid out.  The kite-cover retaining pins, which are attached to the kite flying line, are then withdrawn.  The kite opens automatically, and the kite cover falls away.  The flying line then withdraws a split pin connecting the rocket tow-line to the top of the kite, and the rocket is separated from the kite.









1lb Signal Rocket Mk III (Service)
   

Overall length: 16.4 inches
Maximum diameter: 1.8 inches
Total weight: 1 pound
Color of stars: White
Number of stars: 28


General: This rocket is designed for day or night signalling.


Description: The components consist of a propellant-composition filled case, closed by a wooden plug, and an upper cylinder containing 28 white stars.

The case consists of a rolled paper tube choked near the lower end to form a vent and threaded below the choke to receive the wooden plug.  The tube is filled with rocket-propellant composition, the center of which has a conical cavity.  A clay filling plug with a tapered hole in its center is located in the top of the tube, and the recess and the face of the clay are primed with mealed black powder.  A small charge of rocket composition is dusted over the top face of the clay.  A clay plug with a tapered hole is located immediately above the choke.  The recess and the choke are primed with gunpowder.  A metal socket for accommodating the stick is glued to the outside of the case, and also bound to it with twine.

The cylinder consists of a rolled paper tube filled with 28 white stars.  It is closed at one end by a paper disc covered with a paper cone, and at the other end is attached to the case.  The joints are sealed with paper strips.

The rocket is painted olive drab and carries a white instructional label around the case.  Manufacturing and filling information is stencilled on the cylinder.


Operation: When the wooden plug is removed, the vent is exposed and the rocket is ignited by applying a lighted porfire to the vent.  When the major part of the rocket composition has burned, combustion spreads through the cavity and primed hole in the clay filling to the rocket composition in the cylinder, and thereby ignites and ejects the stars.  The burning stars are ejected at a height of about 900 feet and burn for about 9 seconds.










Buoyant Line-Carrying Rocket No.2 Mk I (Service)
   

Overall length: 28 inches
Maximum diameter: 2.75 inches
Total weight: 3.25 pounds


General: This rocket is fired from a hand-firing rocket projector, and is initiated by a 30-grain percussion cartridge.  The rocket is designed for rescue purposes on marine craft and for use by airfields situated in coastal areas as a means of contacting crews of aircraft which have crashed into the sea immediately after take-off.


Description: The rocket consists of a wooden head made in two halves, held together with screws, which engage the head of the rocket tube.  The rocket propellant composition is contained in the tube, the nose end of which is closed by a wooden plug and a clay plug.  The after end of the rocket tube houses a plaster-of-paris choke, which is covered by a millboard washer and an oiled paper disc.  A conical vent is formed in the rocket propellant composition in line with a  tapered hole in the choke.  The end of the vent nearest the choke and the hole in the choke are coated with gunpowder priming.

A bridle with a hinged stirrup is attached to the rocket, and a tail consisting of a wire cable about 3 feet long is secured to the stirrup.  The part of the tail nearest the rocket is protected from the heat of the burning rocket composition by an asbestos sheath.  The free end of the tail carries a loop for connecting to a buoyant line.

The buoyant line consists of 250 yards of orange colored cotton cord, which is specially treated so that it will float on water.  It is coiled in a square cardboard container whose lid is secured by adhesive tape.

The wooden head is painted yellow overall and filling and manufacturing information is stencilled on the head in black letters.


Operation: When the projector, loaded with rocket and cartridge, is fired, the flash from the cartridge ignites the gunpowder priming in the rocket and at the same time forces the rocket out of the projector.  The gunpowder priming ignites the rocket composition, which then takes over and propels the rocket along its trajectory.  The rocket draws the buoyant line out of its container, and, when expended, falls into the sea and floats on the surface.










3 and 3/4lb Illuminating Rocket No.2 Mk I (Service)
   

Overall length: 30 inches
Maximum diameter: 2.25 inches
Total weight: 3.75 pounds
Height of ejection: 750 feet
Burning time: 45 seconds
Candlepower: 180,000


  
General: This rocket is currently employed only by the Air/Sea Rescue Service to assist in sea rescue searches at night.  It is fired from a hand-firing projector, and is initiated by a 30-grain percussion cartridge.


Description: The rocket consists of a steel rocket tube containing a rocket-propelling composition, which has a conical cavity in the center.  The rocket tube is fitted at one end with a metal center.  The rocket tube is fitted at one end with a metal flare container housing a wooden plug, a flare candle, and a cotton parasheet attached to the candle by a wire strap.  Crimped into the other end of the tube is a wooden choke sealed by a paper disc.

Secured to the rocket tube is a steel bridle, which extends beyond the wooden choke and carries a hinged stirrup.  One end of a steel rope tail is screwed to the base of the stirrup.  The end of the tail is protected from the heat of the burning propellant composition by an asbestos sheath.  The other end of the tail is spliced to form a loop to which is attached a 12-foot hemp rope.  The rope is coiled into a paper envelope, which has a cotton loop attached to it.  The envelope, with the rope inside, is attached to the rocket by a rubber band when supplied.

The wooden plug in the flare container carries a recess which houses a small quantity of gunpowder and a length of quickmatch.  The quickmatch contacts both the gunpowder and the rocket composition.

The flare candle consists of a cardboard cylinder held in place in the flare container with cotton-wool packing, and closed at one end by a wooden block.  This block has a pin passing through it to take one end of the wire strap of the parasheet.  At the other end of the cardboard cylinder is secured a washer, housing a gunpowder charge which is held in place by a muslin disc.  Above this disc is placed a small amount of priming composition.  An illuminating composition fills the remainder of the candle.

The parasheet and the wire strap are packed into the flare container with packing cylinders, and the container is closed by a metal lid secured with adhesive tape.

The flare container is painted aluminum overall.  The filling and manufacturing information is stencilled on the container in black letters.


Operation: When the projector, loaded with rocket and cartridge, is fired, the explosion of the cartridge breaks the paper disc, and the flash passes through the choke and ignites the rocket-propellant composition.  The gases generated by the composition then take over and force the rocket along its trajectory.  When the rocket composition is almost burned through, it ignites the quickmatch.  The flash from the quickmatch initiates the gunpowder in the wooden block.  The flash from the gunpowder ignites the priming composition in the flare candle, which in turn fires the illuminating composition.  Simultaneously, the pressure of the gases from the exploding gunpowder forces the lid from the flare container, and ejects the ignited candle and its attached parachute.  The tail and the hemp rope act as flight stabilizers.









6 and 1/4lb Illuminating Rocket No.1 Mk I (Service)
   

Overall length: 22.5 inches
Maximum diameter: 3.5 inches
Total weight: 6.25 pounds
Height of ejection: 800 feet (approx.)
Burning time: 45 seconds (approx.)
Candlepower: 300,000


General: This rocket is currently used by the Royal Observer Corps to indicate the presence of low-flying enemy aircraft to patrolling fighters, and by the Air/Sea Rescue Service to assist in sea rescure searches at night.  The rocket is fired from a Type B Rocket Projector, Mk III or IV, using a 60-grain percussion cartridge.


Description: The rocket consists of a rocket tube, a sliding tail, and a flare container, which houses a burster charge, flare candle, and parachute.  The rocket tube is filled with a rocket propellant composition, having a conical cavity in the center, and is closed at one end by a gun-metal choke crimped in position.  The choke is closed by a paper seal.  At the other end of the rocket tube are a wooden block and a clay plug, with a hole to receive a length of quickmatch.  The flare container is crimped to a metal junction head secured by screws to the wooden block.  Housed in the junction head are a wooden washer, covered with primed cambric, and the burster charge, which is held in place by another wooden washer.

The flare candle consist of a rolled paper case, strengthened at one end by a tin-plate cup, and held in place by felt packing.  The strengthened end of the case contains a fusible metal cup having a central hole.  This cup houses a quantity of priming composition, which is held in place by a primed cambric disc and a paper washer.  The main illuminating composition of the candle is held in place by a millboard disc.  A suspension cup, riveted to the paper case, carries a piece of wire wrapped at both ends with adhesive tape.  One end of a wire strap is looped around the middle of the wire.  The other end of the wire strap is attached to a 36-inch parachute, which is packed into the flare container between a wooden washer, millboard spacers, and a wooden disc.  The top of the flare container is closed by a metal lid secured in place with adhesive tape.

The sliding tail is of the drum type.  When the rocket is fired, the tail slides along the rocket tube until arrested by the metal choke.  A leaf spring attached to one of the tail fins then holds the tail in the extended position.

The flare container is painted aluminum overall, with filling and manufacturing information stencilled on the container in black letters.


Operation: When the projector, loaded with rocket and cartridge, is fired, the explosion of the cartridge breaks the paper seal on the rocket choke, and the flash passes through the choke to ignite the rocket-propellant composition.  The gases generated by the burning propellant then carry the rocket along its trajectory.  When the rocket composition is almost burned through, it ignites the quickmatch and the primed cambric, which in turn fires the burster charge.  The flash from the burster charge ignites the flare candle and forces the lid from the flare container, ejecting the ignited candle and its attached parachute.









9lb Illuminating Rocket Mk II (Service)
   

Overall length: 36 inches
Maximum diameter: 6 inches
Total weight: 9 pounds
Height of ejection: 1500 feet (approx.)
Burning time: 60-70 seconds
Candlepower: 300,000

  
General: This rocket is currently used only by the Royal Observer Corps to indicate to patrolling fighters the presence of low-flying enemy aircraft.  The rocket is fired from a Type B Rocket Projector Mk IV, using a 60-grain percussion cartridge.


Description: The rocket consists of a steel rocket tube, a tail, and a metal flare container, which houses a parachute, flare candle, and burster charge.  The rocket tube is filled with a propellant composition, with a conical cavity in the center.  At one end of the rocket tube is a gun-metal choke crimped in position and closed with a paper disc.

At the other end of the steel tube is a clay plug provided with a flash hole.  The flare container is fastened with screws to a metal junction head, which houses the burster charge and a length of quickmatch.  The burster charge is held in position by a wooden washer, covered with primed cambric.  Attached to the flare container is a waterproof sleeve, which fits over the projector barrel to prevent rain from entering the barrel when the projector is loaded.

The flare candle consists of a rolled paper case, strengthened at one end by a tin-plate cap and held in place with felt packing.  The strengthened end of the cap contains a fusible metal cup having a central hole.  Housed in this cup are a quantity of gunpowder, priming composition, and two igniter pellets.  The gunpowder and priming composition are held in place by a muslin disc.

The main illuminating filling of the candle is pressed in position and held in place by a millboard disc.  A wooden block, resting on the millboard disc, has a central hole to receive one end of a wire strap, which is lopped around a metal rod passing through the wooden block.  The block is riveted to the paper case.  The other end of the wire strap is attached to a 36-inch parachute, packed in the flare container between a wooden washer, cardboard spacers, and a wooden disc.  The top of the flare container is closed by a metal lid secured to the container with adhesive tape.

The rocket is stabilized in flight by a tail secured to the rocket tube.  The tail consist of four fins attached to a bridle, which is fitted to the rocket tube.

The flare container is painted aluminum overall, with filling and manufacturing information stencilled on the container in black letters.


Operation: When the projector, loaded with rocket and cartridge, is fired, the flash from the cartridge breaks the paper sealing disc, passes through the choke and ignites the rocket-propellant composition, which then forces the rocket along its trajectory.  When the rocket composition is almost burned through, the flame passes through the flash hole and ignites the length of quickmatch and the burster charge.  The flash from the burster charge ignites the flare candle and forces the lid from the flare container, ejecting the ignited candle and its attached parachute.





Next Time: Hand, Rifle, and Anti-Tank Grenades