Nota PBL

TERHAD

96. Pyrotechnic Lock-Up. A steel or masonry box or cupboard, authorized for use
by a competent authority, for the storage of limited quantities of pyrotechnics for
immediate use.

97. Ready Service Igloo. An igloo containing a maximum NEQ of 100,000
kg with a loading density of up to 20 kg/m³

98. Ready Service Storehouse. A traversed or untraversed storehouse containing a
maximum NEQ of 10,000 kg.

99. Ready-Use Explosive Storehouse. A danger building, authorized for use by a
competent authority conveniently sited for the storage of explosives for immediate
issue or use.

100. Red Card (RAF Form 2884). A form to indicate suspect or obsolete explosives
and associated non-explosive stores.

101. Relaxed Conditions. The relaxation, by a competent authority, of the normal
explosives regulations in the special circumstances detailed in – 1C, A8. 102.

SAA. See Small Arm Ammunition.

103. Safety Class Explosives Lock-Up. A building, room or cupboard, authorized
for use by a competent authority, for the storage of limited quantities of Safety
Class Explosives.

104. Safety Cartridges. Those defined as such by the Home Office under the
Explosive Act 1875, via cartridges for small arm of which the case can be
extracted from the small arm after firing and which are so closed as to prevent
any explosion in one cartridge being communicated to other cartridges.

105. Safety Class. Explosives which are packed in such a manner that in the event

of one exploding they will not cause external fire nor produce missile, flame or
blast of sufficient intensity to ignite adjacent packages or injure a passer – by.

106. Segregation. The storage apart but not necessarily in separate
accommodation, of explosives known to be other than serviceable but in a safe
condition.

107. Self – Propelled / Self - Propulsive. An explosive item incorporation its own
means of sustaining flight and unable to comply with the non – self – propulsive
requirements (qv).

108. Sentence. A written decision as to the condition of explosives, etc, as the result
of an inspection. The authorized sentences are:

a. Serviceable (S). Fit for all purpose for which the items are held.
35

TERHAD

TERHAD

b. Repairable (R/S). Capable of being made serviceable by repair.

c. Unserviceable (+). Unfit for use and beyond repair.

d. Unclassified (U/C). Needing further inspection before classification as
serviceable, repairable or unserviceable.

109. Service Life. The item for which an explosive item in specified storage
conditions and when subsequently used in its operational and/or training
condition may be expected to remain safe and serviceable.

110. Shifting Lobby. An entrance room in a danger building divided by a barrier
into a ‘Clean Area’ and ‘Dirty Area’, in which personnel exchange their outer

clothing for magazine clothing (and vice versa).

111. Small Arms Ammunition. Ammunition fired from weapons not above 20 mm.

112. Small Quantity. Any quantity of small arms ammunition (Safety Class), or not
more than 91 kg of explosive substance in other explosives, the storage of
which is permissible under relaxed conditions.

113. Spalling. The creation by shock waves emanating outside a building etc, of
high speed particles within that building itself is not breached.

114. Storage Life. The time for which an explosive item in specified storage
conditions may be expected to remain safe and serviceable.

115. Sub-Station. A Sub-Station in an assemblance of equipment at once place
including any necessary housing for the conversion, transformation or control
of electric power. (glossary of term BS 205, Term No. 5405).

116. Sympathetic Detonations. Detonation of a charge by exploding another
charge adjacent to it.

117. Totally Enclosed. As applied to electrical installations, means the ‘live’

parts are enclosed by a cover or covers having no openings for ventilation

(Glossary of Terms BS 205, Term No. 3830).

118. Traverse. A natural or artificial barrier, the purpose of which is to localize
the effects of an explosion within the barrier and to minimize the effects of an
external explosion.

119. Type. A division of ammunition in accordance with its general design, eg.
AP, SAP, Nose Ejection.

36
TERHAD

TERHAD

120. Underground Danger Building. A danger building or storage site, the ceiling
of which is more than 610 mm below the natural ground level.

121. Unit Load. The unit formed when packages or unpackaged articles are
assembled on or in a device which enables them to be mechanically handled
as one unit, but which is not a freight container.

122. Unit Risk. See maximum credible event.

123. Unit Returns. Explosives and associated non-explosive stores returned from
a user unit to an ammunition depot or park.

124. Yellow card (RAF Form 4004). A form to indicate explosives and

associated non-explosives stores which are due for or are undergoing

inspection.

SEKOLAH SISTEM MATERIEL

INSTITUT LATIHAN PENGURUSAN MATERIEL

TUDM KINRARA

BASIC THEORY OF EXPLOSIVES

The Phenomenon of Explosion

1. An explosion is a violent expansion, usually of gaseous matter, the energy of
expansion appears primarily in the form of HEAT & LIGHT. Explosions can be
categorized into 3 types;

a. Physical,
b. Chemical, and
c. Atomic.

2. Physical explosions are the consequence of the failure of a pressurized vessel
such as, for example, a steam boiler or liquid gas cylinder, but explosions of military
and industrial interest are produced by explosives or explosives systems, the latter
being mixtures of fuels (hydrogen, coal gas, petroleum vapor, coal dust, flour, charcoal
etc) and oxidants (air, oxygen, nitrates, chlorates, etc). The subject of atomic energy
for the production of explosions falls outside the scope of this instructional and
therefore discussion here will be confined to conventional explosives only.

The Nature of Explosives

3. Consideration of gaseous explosive systems in particular makes it part
apparent that in them explosion is a special form of combustion. The fuel is in intimate
contact with oxygen (pure or as a constituent of air), so that when a suitable source of
ignition is applied the adjacent fuel burns with extreme rapidity. Because of this
rapidity, the heat of combustion developed in the spherical element around the initial
point of ignition acts in two ways before it has time to defuse away:

37

TERHAD

TERHAD

a. It imparts ignition energy to the adjacent spherical zone.

b. It expands the gaseous products of combustion.

These effects proceed with such rapidity that a shock wave is produce in the system, and
it was the study of the such shock phenomenon which lead to current theories of
detonation.

4. Such gaseous systems are of only limited military interest. The explosives of
prime concern in the military sphere are usually solids (for example, Gun Powder,
TNT) or liquids (for example, nitroglycerine), but the basis of their functioning remains
the same, namely that in them fuels are in intimate contact with oxidants. In
gunpowder, for example, the fuels (charcoal and sulphur). In an explosive chemical
compound, such as TNT or nitroglycerine, the fuels (carbon and hydrogen) are present
with oxygen in the characteristics molecular structure of the compound.
Such condensed (that is, non-gaseous) explosives have the characteristic that their
combustion to yield gaseous products, gives rise to a much greater relative change in
volume of the system than occurs with gaseous mixtures.

GENERAL THEORY OF EXPLOSIVES

4. If a particle of an explosive is subjected to heat so as to cause a rapid increase in
its temperature, a temperature is reached at which the rate of exothermic
decomposition becomes significant (eg. 500º - 1700ºC).
6. The heat liberated by decomposition increases the rate of reaction and resulting
rate of increase in temperature is exponential. At the temperature characteristic of the
particular explosive the output of heat is sufficient to enable the reaction to proceed
and be accelerated without the input of heat from another source.

7. At this certain temperature called the IGNITION TEMPERATURE, a surface
phenomenon known as DEFLAGRATION begins with the reaction products flowing
away from the unreacted material below the surface (F162).

8. Deflagration of all the particles in a mass of finely divided explosive can occur
nearly simultaneously. In such a case the confinement of the particles within the mass,
because of the viscosity of the gaseous products, has the effect of increasing
pressure. Increase in pressure in turn, has the effect of increasing the rate of reaction
and temperature.

9. The sudden and intense pressure results from the very rapid breakdown of the
explosive into products which are principally or entirely gaseous. The formation of
gases is accompanied by the simultaneous liberation of heat which further augments
the pressure exerted by the gases. Thus the essentials of an explosion are:

a. The formation of a large volume of gases,

b. The simultaneous liberation of a large quantity of heat.

38

TERHAD

TERHAD

c. Rapidity of breakdown of the explosive substance.

d. Confinement.

10. The high pressures generated are of the order of 20 tons per square inch for
the burning of a propellant in the chamber of a gun, or as much as 300 tons per square
inch for a high explosive. This large transient pressure from a high explosive serves
to rupture the solid matter within which it is contained and project its fragments at high
velocities.

11. The final effect of Deflagration under confinement is Explosion which may be
either violent deflagration or even detonation.

12. In the case of low explosives such as loose black powder and pyrotechnic
compositions only violent deflagration can take place, without appreciable effect on
the surface on which it had been placed. The newer high explosives (eg.
Nitroglycerine) if similarly ignited in the open burned with a degree of rapidity and
violence and might shatter the surface on which they had stood. The shattering effect
or ‘Brisance’ of various explosives depends upon the rate at which the detonation
takes places, and on the energy content of the explosive. To measure brisance a
sample of explosive is detonated on a ‘Standard Shell Plate and the amount of
indentation or perforation of the plate is proportional to the violence of the explosion.

Characteristics of Detonation

13. Produces a shock wave which is supersonic in the explosive. This shock wave
is the detonation wave.

14. The velocity of the shock wave has a limiting valve which is characteristic of the
particular explosive. This limiting shock velocity is the Velocity of Detonation or
Detonation Velocity (D) of the explosive.

15. The Detonation velocity (D) always exceeds the velocity of sound in the
explosive. In practice, Detonation lies between 2000 and 9000 meters/sec depend on
the explosive.

16. For solid explosive charges, D increases with charge density up to the limiting
value of the crystal.

17. A detonation wave is an intense compression shock wave, which exerts an
extremely high pressure in the shock front. This pressure is the Detonation Pressure
(P). In practice, p lies between 80 and 390 kilo bar.

SEKOLAH SISTEM MATERIEL
INSTITUT LATIHAN PENGURUSAN MATERIEL

TUDM KINRARA

39

TERHAD

TERHAD

SENSITIVITY OF EXPLOSIVE

Definition

1. Sensitivity refers to the case with which an explosive can be initiated by a
suddenly applied mechanical force or other form of energy.

2. Sensitivity. All explosives are sensitive in some degree to the effects of:

a. Mechanical shock (Direct Impact)

b. Friction or

c. Heat (Flash or Spark)

3. The degree of sensitivity of explosives varies over a wide range and
independent on several factors, these are detailed below.

4. Factors Affecting Sensitivity. The sensitivity of explosives depends upon:

a. Their chemical constitution.

b. Their physical properties.

c. The nature of impurities present and

d. The nature of the shock to which the explosive is subjected.

5. Chemical Constitution. As a general observation the majority of explosives
contain nitrogen in the form of nitro or nitro groups, the greater the number of
nitro groups present the greater the sensitivity of the substance.

6. Physical Properties. The sensitivity of solid explosives depends on the size,
shape and hardness of its crystal and how densely the crystal are packed.
Frictional effects between crystal can cause local heating.

7. Impurities Present. The presence of grit makes an explosive more sensitive,
this is due to the increase friction which is liable to be set up and varies with the
around and hardness of grit.

8. Nature of Shock. The effects of shock on the sensitivity of an explosive varies
with the type of explosive and its intended use. For example, the initiator
explosives must respond to a relatively light blow (pistol striker) while the main
filling of a bomb should only respond only respond to the detonation of an
intermediary explosive.

FIGURES OF INSENSITIVITY
40

TERHAD

TERHAD

9. F of I is the value given to all known high explosive. It is a result of impact test
of picric acid. It was given the nominal F of I of 100. Sensitive explosive have a
lower F of I and more stable explosive the higher the F of I.

STABILITY

Definition

10. Stability refers to the extent of physical or chemical change which an explosive
may underage in storage.

11. Stability. Whilst all explosives are at all times more o less instable, if unsuitably
packed, stored or handled their instability may increase and they may become
dangerous. Additionally, any change in the composition of an explosives, with
few exceptions, invariably means greater danger.

12. Major factors that can effect the stability of an explosive are:

a. The nature of the explosive.

b. Impurities.

c. Temperature.

d. Humidity.

13. Nature of the Explosive. Some explosives as part of their nature are unstable
and decompose slowly under all conditions. The decomposition rate increases
with time and may reach a point where spontaneous combustion occurs.
Cordite is an example.

14. Impurities. Small quantities of impurities often have an adverse effect on
stability and every effort is made during manufacture to reduce these to a
minimum.

15. Temperatures. A cool, even temperature is most suitable for explosives. High
temperatures increase the rate of decomposition of certain explosives where’s
extremely long temperatures will adversely effect compositions containing
nitroglycerine. In this case the nitroglycerine readily freezes and forms crystal
which are highly sensitive. When the temperature rises the crystals will be
reabsorbed, however, they may disturbed unevenly and will result in unreliable
effects.

16. Humidity. Certain explosive compositions, some more than others will absorb
water from the air particularly in hot and humid climates. The amount of water

41

TERHAD

TERHAD

absorbed is generally small it may be sufficient in some explosives it cause
chemical changes in the explosive.

EXUDATION

17. Exudation is the term given to various solids and liquids which sometimes seep
from a bomb or shell around the base plate, filling cap or fuse pocket. Exudation
is the result of:

a. A chemical breakdown of the filling.

b. Contact with air or moisture.

c. The age of the store.

18. Extreme care is necessary when dealing with exudation as the substance may
contain chemicals which can only be described as extremely sensitive. Amatol,
which contains TNT and ammonium nitrate, is a filling which may gave trouble
due to exudation. Ammonium nitrate, if in contact with the air, absorbs moisture
and forms a yellowish liquid. The liquid tends to seep through the seals of the
store and appears as a yellowish liquid, or it may dry off on the outside of the
store leaving a white encrustation. In itself, this type of exudation is quite
harmless, but it is corrosive and in contact with copper or copper alloys, it forms
blue or green crystals which exudation if it contains any impurities, as these
impurities tend to liquidity and seep from the store as a brown substance which
has slight explosive properties.

EXTRUSION

19. Extrusion is the result of the thermal expansion of the explosive filling forcing
the sealing composition out through the threads of the explosive container or
filling plug, or past the edge of the closing plate.

20. Extrusion seldom occurs unless the store is subjected to a sustained
temperature exceeding 90 degree F. Extrusion may be identified by the sealing
compounds used which are either black or dark brown and have the
appearance and substance cobblers wax.

EXUDATION, EXTRUSION – REMOVAL

21. Extrusion is removed in the same manner as exudation. Stores which show
signs of extrusion and/or exudation are to be transported to an isolated site.
Extreme caution is to be exercised in handling and moving the store. The item
if it is a bomb is not to be rolled and is to be firmly attached to the handling
conveyance being used.

42

TERHAD

TERHAD

22. The method of removal of the exudation or extrusion is to be carried out in the
following manner:

a. A clean, soft cloth, thoroughly sacked in warm water, is to be applied to the
exudation to soften it. When it is soften, gently wash it off using the warm water
liberally.

b. If the removal proves stubborn, gently scrape off the substance using a wooden
scraper, take care to keep the substance wet with warm water during the operation.

* Notes:
THE ABOVE PROCEDURE IS TO BE CARRIED OUT BY TRAINED
ARMAMENT PERSONNEL AND NOT BY EQUIPMENT PERSONNEL

INITIATION OF EXPLOSIVES

23. Explosives are comparatively unstable and sensitive materials. A small,
localised stimulus applied to the explosive will initiate the substance. In
practice, explosives may be initiated by different methods. These being:

a. Flame: Some uses of initiation by flame are:

(1) Ignition of gun powder in safety fuse.

(2) Igniters in shell cartridge cases.

b. Electric Spark, and Hot Wire: This method of initiation is used in:

(1) Electric Detonators.

(2) Electric Igniters.

c. Percussion: Common uses of this form of initiation are:

(1) In percussion fuses (to initiate the detonator).

(2) In percussion primers (to initiate the cap).

d. Friction: This method of initiation is used frequently III the pyrotechnic field for
initiating:

(1) Matches.

(2) Cracker type stores.

(3) Pull wire igniters.

43

TERHAD

TERHAD
e. Shock Wave: The impact of a high velocity shock wave, in the form of a detonation

wave from a donor explosive charge, will initiate detonation in a receptor explosive.
Applications of this method of initiation are:

(1) In detonating trains in HE shells, mines and bombs, the main filling is
initiated by the impact on the detonation shock wave from the primer.

(2) In 'sympathetic detonation', the detonation of a high explosive charge may
set off a neighbouring charge.

f. Electromagnetic Fields: Radio frequency fields may cause initiation of explosives
due to direct heating, or by induced currents in leads which are in contact with
explosives. The effect depends on the strength and wavelength. With the advent of
more and more electronic equipment in the work place, the hazard to explosives is
becoming more pronounced, and extensive investigations are being carried out into
what has become known as RADHAZ.

g. Chemical Reaction: Spontaneously inflammable chemical reactions may be used to
initiate explosives, however this method of initiation is normally only used in the
insurgency field, for 'home made' terrorist devices.

44
TERHAD

TERHAD

SEKOLAH SISTEM MATERIEL
INSTITUT LATIHAN PENGURUSAN MATERIEL

TUDM KINRARA

CLASSIFICATIONS OF EXPLOSIVES

1. The classifications of explosives are as follows:

a. High explosives (detonating explosives).

(1) Primary (initiator/detonators).
(2) Secondary (intermediaries/boosters & main fillings for warheads).

b. Low explosives (burning explosives).

(1) Propellants.
(2) Pyrotechnics & miscellaneous compositions.

HIGH EXPLOSIVES

2. High explosives create more pressure and burn more quickly, detonating
almost instantaneously. The proper use of high explosives by today’s
explosives engineer, produces minimal ground vibrations and air overpressure.

3. The first high explosive used in commercial blasting was nitroglycerine, also
called "blasting oil." Nitroglycerine was dangerous to use because it is an
unstable chemical. But in the late 1800’s, a Swedish chemist, named Alfred
Nobel, invented dynamite by mixing nitroglycerine with a special clay, called
kieselghur, and packed it into sticks.

4. Dynamite became the first safe high explosive used. It can be dropped, hit with
a hammer or even burned and will not accidentally explode. There are a
number of different types of dynamites being used today, all containing
nitroglycerine.

5. High Explosives, which normally function by detonation are used to effect
damage and demolition. As a result of the detonation the materiel surrounding
the high explosive is ruptured and its fragments projected at high velocities.
Additionally a blast effect acts in all directions and causes great disruption close
to the source of detonation.

6. High explosives constitute the filling of the bombs, shells, mines, depth changes
and torpedo warheads etc. They are also used for field demolition work and
blasting. However, military requirements for high explosives differ in many

45

TERHAD

TERHAD

respects from those for commercial users. Some of the special requirements
for high explosives are:

a. Possession of power and violence.

b. Insensitivity to shock and friction.

c. Stability under all conditions.

d. Easy to pour and mould on manufacture, and

e. Easy to manufacture from readily available cheap raw materials.

7. Examples and properties of the main high explosives in service use given are
below.

8. TNT (Trinitrotoluene). TNT or Trinitrotoluene is the most common high
explosive today and has been a major constituent of high explosive fillings since
1914. TNT is manufactured from a coal tar product, toluene, a liquid similar to
benzene.

9. Pure TNT is a pale yellow crystalline solid that melts at 81.19 C without
decomposition. This property allow TNT to be melted in steam heated vessels
and poured into bombs and other stores.

10. TNT, when pure, is fairly insensitive (figure of insensitiveness 115) and may be
handled without undue risk, even to the extent of being ground in mills. It is not
easily detonated, but once initiated, it detonates with violence and fair power.

11. Poorer quality TNT’s were subject to exudation which was explosive in nature.
Modern TNT’s are very stable in storage and are not prone to exudation. It is
not usually used by itself but is used as a constituent of a large number of mixed
explosives which are used as high explosives. eg. TORPEX, RDX/TNT.

12. Amatols. The amatols consist of mixtures of ammonium nitrate and TNT.
The addition of ammonium nitrate to TNT was originally made to conserve
supplies of TNT. A further reason lay in the fact that the excess of oxygen
contained in the ammonium nitrate helped compensate for the deficiency of
oxygen in TNT. They are sensitive to moisture because of the ammonium
nitrate content and should not be allowed to come into contact with copper or
its alloys since ammonium nitrate may form sensitive copper compounds which
under favorable circumstances are capable of initiating the bulk of the
explosives.

46

TERHAD

TERHAD

13. RDX. RDX, Research Department Explosive No. X was discovered by the
Germans in 1899 but did not come into British Service use till 1939. It is
considerably more powerful than TNT but owing to its sensitivity, it cannot be
used alone as a main filling. When mixed with other explosives or with small
quantities of desensitizing substances, such as been wax, it forms explosives
mixtures which are sufficiently insensitive for safe use and which form a group
of the most powerful high explosives at present in use in the service. Its
manufacture is expensive in comparison with other explosives. RDX
compositions include RDX/TNT, RDX/Bees Wax, PE, RDX/Wax/Aluminum.

14. Amatex. Amatex is a mixture of ammonium nitrate, TNT and RDX. It is used
as a main filling for medium capacity bombs because of its ability to sustain the
detonation wave through the large mass of the filling of the bomb. Amatex is
often used in preference to amatol in large bombs as complete detonation of
amatol fillings is frequently not achieved.

15. Plastic Explosive (PE). Plastic Explosives consist of RDX which has been
mixed with a suitable ‘Plasticiser’. The plasticiser serves the two fold purpose

of desensitizing the RDX and of giving the resulting mixture a putty like

consistency. PE is used as a demolition explosive particularly as a cutting agent

for steel girders and railway lines.

16. PETN. Sometimes known as Penthrite. It is a very powerful and violent

explosive and is too sensitive for use alone as a bursting charge. It can be

desensitized by mixture with other substances such as wax.

17. Pentolite. Consist of a 50/50 mixture of PETN and TNT. An extremely sensitive
explosive, which was used during World War II (WW II).

18. Tetryl (Trinitrophenyl Methylnitramine). Composition exploding. Is a very
sensitive explosive (F of I 70-75) which when initiated detonates with great
violence. Stability in storage is good and it shown no tendency to exude. Its
main use in the service is as an intermediary explosive in the initiating system
of aircraft bombs.

19. Prim cord and Cordtex. Prim cord and Cordtex are cord form of fuses and
consists of a core PETN contained in either a bituminous compound
surrounded by a waxed fabric or in a plastic tube.

20. Aluminized Explosives. The aluminized explosives consist of normal high
explosives to which a varying percentage, to a maximum of about 20% of
aluminum has been incorporated, the aluminum being in the form of finely
divided powder. The function of the aluminum powder is to greatly increase the
heat of detonation of the normal explosive and thus its power or blast effect.
Examples of aluminized explosives are torpex, ammonal, minal.

21. Plastic Bonded Explosives. A new series of explosives known as
‘Plastic Bonded Explosives’ (PBX) has been under development during the past few
years. These PBX’s are explosive fillings which can withstand temperature of 300

47

TERHAD

TERHAD

degree F and are being developed for modern bombs designed for external carriage
at supersonic speeds and for fillings of guided weapons where, in both instances, the
filling is subject to high temperatures. High Welting Explosive (HMX) and Diamino
Trinitron Benzene (DATB) are the two explosives from which PBX has been
developed.

PRIMARY EXPLOSIVES

22. Primary explosives are those high explosives which can be brought to full rate
of detonation almost instantaneously, and have a relatively low Figure of
Insensitiveness (F of I). They have a low V of D (between 2,000 to 5,000 m/s)
and posses a high shattering effect due to the detonation shockwave. This type
of explosive is referred to as initiators/detonators and are generally used to
initiate Secondary Explosives.

INITIATORS/DETONATOR

23. Initiator/detonator is primary explosives. Are those high explosives which can
be brought to full rate of detonation almost instantaneously by a small initial
impulse. They are used to initiate the action of detonation in other less sensitive
high explosives.

24. These types of explosives are invariably classified as a sub group of high
explosives as not all initiators are disruptive or a true explosive. Initiators may
be divided into two groups:

a. Disruptive, and

b. Igniferous (cause to burn).

25. Disruptive Initiators. Are a very sensitive explosive under which the influence
of a relatively light blow or flash, burn almost instantly to detonation. Owing to
their greats sensitivity they can only be safely used in very small quantities,
being generally compressed into metallic capsules.

26. The following are special requirements of an ideal disruptive initiator:

a. Certainty of response.

b. Quickness.

48

TERHAD

TERHAD

c. Stable sensitivity and

d. Freedom from ‘dead pressing’.

27. The initiators in use are Mercury of Fulminate, Lead Styphnate and Lead Azide
all of which are very sensitive (average F of I 16) and do not have a high degree
of chemical stability. They are mainly used as a filling in detonators.

28. Igniferous Initiators. Are sensitive mixtures which are designed to produce
flame for the purpose of initiating the process of burning in enclosed in some
form of metal cap and may be initiated by percussion, heat, flame or friction.
These initiators cannot be used to directly start detonation nor are they
themselves capable of being detonated except under abnormal conditions.

29. Due to their usage as fillings in percussion caps, fuses, SAA cartridges or
detonators they must be sensitive to percussion, on the other hand they must
be sufficiently insensitive to withstand minor shocks to which they could be
subjected to in ordinary service use. In addition, the mixtures must be stable
and not liable to deterioration due to humidity or temperature variations.

30. Igniferous initiators should not be confused with disruptive initiators which
contain high explosives and are designed to detonate and initiate detonation.

SECONDARY EXPLOSIVES

31. Secondary explosives are relatively insensitive substances or mixtures, which
will detonate, when initiated by a shock wave but which normally will not
detonate when heated or ignited. They have a V of D greater than 5,000 m/s.
They are considered more powerful than primary explosives, and are used as
main charge fillings for projectiles, bombs, torpedoes, mines and comprise the
main component of demolition charges.

INTERMEDIARY EXPLOSIVES

32. Intermediaries are used to enlarge and transfer the impulse given by the
initiator explosive to a degree sufficient to detonate the insensitive explosive
used as the main filling. They are generally more sensitive than the main filling,
yet considerably less sensitive than the initiator explosive. It is desirable that
they be as powerful as possible so as to produce a violent impulse.

33. The main intermediary in service use is Tetryl (CE), although picric acid
crystals, TNT crystals, PETN and pentolite have been used as intermediaries.

LOW EXPLOSIVES

34. For many years, black powder was the most common low explosive used
throughout the world. But black powder, or gun powder as it was commonly

49

TERHAD

TERHAD

called, produced a large amount of smoke and was dangerous to use. Today
black powder is still used for pyrotechnics (fireworks), special effects, and other
specialized work, but it has been replaced in commercial blasting by safer, more
productive explosive materials.

35. Low Explosives are an explosive substance which decomposes rapidly through
combustion with the evolution of heat and flash, and generate a large quantity
of gaseous products. They have a V of D less than 2,000 m/s. Low explosives
are not designed to detonate but to burn fiercely when correctly initiated.

PROPELLANTS

36. Propellants are explosives which are used to drive a projectile, for example, a
shell from a gun or a rocket missile. They do not detonate in a violent
destructive manner but produce gases which burn at low and controlled rates.

37. An ideal propellant should comply with the following conditions:

a. The rate of burning should be regular and controllable.

b. It should be smokeless.

c. It should leave no residue.

d. It should be fleshless.

e. There should be minimum erosion.

f. It should be easily ignited.

g. No output of poisonous fumes.

h. Stable in storage.

i. Safe to handle and transport and,

j. Easy to manufacture from readily available raw materiel.

TYPES OF PROPELLANTS

38. Single base. Single Base propellants, which consist of Nitrocellulose blends.

39. Double base. Double base propellants consisting of a gelatinised mixture of
Nitrocellulose and Nitroglycerine.

50

TERHAD

TERHAD

40. Triple base. Triple base propellants or flashless propellants, based on
gelatinized Nitroglycerine/Nitrocellulose - Nitroguanidine (Picrite) mixtures.

41. Composite propellants. Composite propellants, which consist of a polymer
fuel/binder and an oxidiser.

42. Liquid propellants. Liquid propellants, subdivided into two classes;
monopropellants and bipropellants.

43. Examples of the most common shapes in which propellants are found is shown
at Annex A.

PYROTECHNICS - GENERAL

44. According to early Chinese writings some form of fireworks based on 'weak'
gunpowders (that is of low saltpetre content), were known before 1000 AD and
were developed into devices which, while no more than toys from the modem
standpoint, could be used to cause alarm among enemy troops.

45. In Europe, the development of fireworks proceeded rather slowly, but it is
known that early in the 17th century mixtures of saltpetre, sulphur, charcoal and
antimony sulphide, (combination of metal with sulphur) with various oils and
resins were used to make brightly burning 'stars', and that iron filings were used
in similar compositions to give sparks, and verdigris to colour the flame.

46. Pyrotechnics are used for the following purposes:

a. Illuminants - aircraft flares and photo flash.

b. Signal compositions - coloured stars and smoke.

c. Smoke compositions - wind direction and smoke screens.

d. Marine Marking compositions - smoke and flame indications on water.

e. Exploding compositions - battle noise simulators.

MISCELLANEOUS PYROTECHNIC COMPOSITIONS

47. Pyrotechnics, broadly defined, are an explosive store generally containing
combustible material for the production of flame, heat, light, smoke or sound.

48. Pyrotechnic compositions intended to produce light are required in three main
fields:

a. Illumination.

b. Signals (including tracking flares for missiles) and
51

TERHAD

TERHAD

c. Tracer ammunition.

ILLUMINATING AND SIGNAL COMPOSITION

49. Illuminating and signal composition are required to provide steady sources of
light, in the one instance to illuminate targets for visual or photographic
reconnaissance and in the other to penetrate considerable depths of
atmosphere to give distinctive signals identifiable against adverse
backgrounds.

50. The specter of illuminating and colored signal flames are composed of three
distinct elements:

a. A combustible materiel.

b. An oxidizing agent.

c. A metallic salt to give the required color to the flame.

TRACER COMPOSITION

51. A special type of light-producing composition is the projectile tracer
composition. Tracer compositions are sometimes covered with a thick layer of
a more slowly burning igniter composition in order to avoid:

a. Too much glare in the eye of the observer / gunner at short range.

b. Emitting so much light all along the trajectory as to disclose to the enemy
the point of origin.

SMOKE

52. Compositions to produce smoke are required either to give a screaming effect
or for signals. A special variant of the latter is a composition to give both smoke
and flame for use at sea (example: for ejection from a submarine).

COLOURED SMOKE SIGNALS

53. Colored smoke signals are used in daylight only and in practice only five colors

are used in service, Orange, which is most easily recognized color against gray
seas and skies, is universally used as a ‘Distress’ signal color. The other four,

selected for their distinctiveness under most weather conditions, are red,

yellow, green and blue. To obtain adequate smoke density it may be necessary

52
TERHAD

TERHAD

to burn a composition at a rate of 1 1b per minute. Colored signal smokes can
be produced by:

a. Chemical reaction which generate them.

b. Dispersing finely divided colored materials and

c. By vaporizing dyestuffs.

54. In practice only the last method is satisfactory from the volume of smoke and
density of color required. Colored smokes are used in two ways, either as an
instantaneously produced ‘puff’ or ‘smoke burst’ lasting from a few seconds to
several minutes.

Markers and Signals (used at sea)

55. Some Pyrotechnic stores used at sea as markers or signals are required to give
visible indications both by day and by night for extensive periods. The basis of
filling of these stores is red (amorphous) Phosphorus which when ignited, burns
with a lambent yellow flame and emits a dense white smoke.

Flame and Heat Producing Compositions

56. There is a requirement for a range of compositions to ignite explosive and non-
explosive materials, and this requirement is met by pyrotechnic compositions
of one kind or another. ‘Igniter’ compositions for propellant explosive systems
give hot flames, usually accompanied by sparks and hot gases, for relatively
short times.

‘Priming’ compositions give hot slogs, sometimes without production of gas.

Incendiary Compositions

57. In general, incendiary materials fall into two distinct groups. The first group is
composed of metals and alloys which burn in air with a high heat of combustion
and tend to concentrate their heat in a small areas and the second is of
combustible fluids which spread over the target while burning.

58. The two metals most useful as incendiary agents are aluminum and
magnesium, which combine high heat of combustion with reasonable low
melting points. They cannot well be used as powders because, if ignited by a
small explosive charge, they tend to be dispersed and burn explosively as a
dust cloud in the air.
53

TERHAD

TERHAD

59. Liquid fillings are ignited and scattered over the target by explosive charges,
and are rendered more effective if they are ‘gelled’. The hydrocarbons are
gelled by addition of aluminum soaps (cleat or laureates), Perspex or rubber.

60. General. In quite early times the desire to attack the enemy from a distance led
to the development of the sling and in due course ballista, which was soon used
to hurl masses of burning matter into besieged towns.

61. The early literature on Greek Fire shows that the substance was petroleum
distillate thickened by dissolving it in resinous and other combustible matter.

62. The most common incendiary materials in use today are petroleum gels,
magnesium and white phosphorus. Aircraft dropped incendiaries are usually
streamlined aluminium canisters containing a petroleum gel mixture (napalm)
with two igniters, which contains a white phosphorus or a magnesium mixture.
Two multidirectional impact fuses are used to initiate the igniters, which in turn
ignite the petroleum gel on impact with the ground. The ruptured containers
then scatter the burning gel, which will adhere to the target.

Explosive Reactions – Physical

63. Burning - The majority of explosive substances can be readily ignited in the
open air and many will bum relatively slowly in that condition.

64. Deflagration - When the process of burning is capable of being sustained at an
increased rate of burning. This rapid, self-sustained burning of an explosive is
known as deflagration. If contained within a vessel with a venting port, this will
produce a pressure build up resulting in thrust, with the pressure exiting the
vessel via the venting port. If contained within an enclosed vessel, this will
produce a pressure build up, which may result in an explosion.

65. Detonation - Detonation is a different process to deflagration as it requires a
supersonic shock wave to pass through the explosive material. A detonation
shock wave travels at between 2,000 to 10,000 m/s (approximately).

66. Bum to Detonation - If the rate of burning in a burning or deflagrating explosive
increases, due to cracks, contamination or confinement, it is possible for the
rate of burning to exceed the local speed of sound. This will produce a
shockwave within the explosive material and may cause the matedal to
detonate. This is referred to as "burning to detonation" or "going high order".

Annex:

A Common shapes of Propellant.

B Salts used for illuminating and signal composition.

54

TERHAD

TERHAD

ANNEX A

COMMON SHAPES OF PROPELLANTS
(NOT TO SCALES)

55
TERHAD

TERHAD

STICK OR CORD SLOTTED TUBE

TUBE

STRIP OR RIBBON SQUARE FLAKE
CLYINDRINE GRAIN

56
TERHAD

TERHAD

A
N
N
E
X
B

COLOUR

The salts used for coloring the flames are salts of the following metals which produce
the characteristic color listed.

Metals Flare Coloring

Sodium Yellow
Barium Green
Copper Blue
Potassium Violet
Calcium Orange-Red
Red Phosphorus Red

57
TERHAD

TERHAD

EXPLOSIVE TRAINS
1. The most common incendiary materials in use today are petroleum gels, magnesium

and white phosphorus. Aircraft dropped incendiaries are usually streamlined
aluminium canisters containing a petroleum gel mixture (napalm) with two igniters,
which contains a white phosphorus or a magnesium mixture. Two multidirectional
impact fuses are used to initiate the igniters, which in turn ignite the petroleum gel on
impact with the ground. The ruptured containers then scatter the burning gel, which
will adhere to the target.
Types of Explosive Trains
2. The types of explosive trains are:
a. Disruptive train (shock wave).
b. Igniferous train (flame producing).
3. The explosive components of an explosive train include:
a. The Initiator or detonator comprising a small amount of sensitive explosives.
b. The Intermediary (booster) or primer comprising a medium amount of relatively

insensitive explosives.
c. The Main filling/Warhead comprising insensitive explosives. As the warhead

contains the most explosive content, it must be insensitive to withstand
handling and operational extremes, for example, the shock of being fired from
the barrel of a gun.
Safety Mechanisms
4. The purpose of the Safety Mechanism is to:
a. Provide a barrier between the sensitive and insensitive explosive components
until the arming sequence has been completed.
b. Aids handling, storage and delivery of the ordnance.

58
TERHAD

TERHAD

5. The types of Safety Mechanisms (Safety & Arming Devices), employed in the
explosive ordnance, depends on the type of "ARMING" process of the store.

6. The types of Safety and Arming Devices include:

a. Safety pins.

b. Shutter and rotor.

c. Clockwork mechanisms.

d. Internal devices.

SEKOLAH SISTEM MATERIEL
INSTITUT LATIHAN PENGURUSAN MATERIEL

TUDM KINRARA

TYPES OF EXPLOSIVES

‘High’ and ‘Low’ Explosives

1. The rates of combustion of explosives may vary greatly, depending not only on
their composition or chemical constitution but also on their physical form, their degree
of confinement (for example, loose powder, compressed charge, light container heavy
shell) and the nature of the means employed to initiate their combustion. Rates varying
from a few centimeters per minute to 8500 meters per second have been measured.
Relatively low rates (say, up, to 400 – 500 meters per second) are characteristic of
gunpowder and ‘Smokeless Powder’, which at one time were known as ‘low’
explosives in contrast with the more rapidly burning ‘high’ explosives.

High Explosives and Their Detonation

2. A true explosive is characterized by the fact that in its combustion process an
exothermic (that is, heat-liberating) reaction wave passes through it following and
supporting a ‘shock front’. This phenomenon is described as ‘Detonation’ and the
velocity of the wave is the ‘Velocity of detonation’ in the explosive under the conditions
of the system. As has been stated, the rate of combustion of an explosive may depend
on a number of factors, but in all instance conditions can be found in which a maximum
value of the velocity of detonation can be measured, characteristic of the particular
explosive and known as its ‘Stable velocity of Detonation’. But, depending on the
design of the explosive system, detonation may occur at a velocity well below the
maximum, when it is described as ‘low-order detonation’, or at a velocity only a little
below the maximum, corresponding with ‘high-order detonation’ – and consequently
with a usually more acceptable order of efficiency of the system from the military
standpoint.

59

TERHAD

TERHAD

DETONATION
3. The mechanism of detonation utilizes the established laws of conservation of
mass, energy and momentum. After the detonator function, a ‘detonation zone, in
which the chemical reaction is t-5 aking place, travels through the column of explosive.
This detonation zone is generally considered to include a very narrow shock zone (10
cm) or shock wave. Little or no chemical reaction occurs in this shock zone, but the
pressure reaches its peak. The detonation zone includes not only this shock zone, but
also the chemical reaction zone (0.1 – 1.0 cm). Following this detonation zone are the
detonation products. In front of the shock zone is the unreacted explosive in its original
state of density, pressure velocity and temperature.

4. At or near the beginning of the chemical reaction zone, the high temperature to
which the material is raised by compression in the shock zone initiates chemical
reaction. Maximum density and pressure occur at the beginning of the reaction zone,
while the temperature and velocity reach their peak at the completion of the chemical
reaction. The detonation products flow with great velocity, but of lesser degree than
the velocity of the detonation zone, toward the undetonated explosive. This is
characteristic of detonation in contradistinction to deflagration, in which case the
reaction products flow away from the unreacted material. The velocity of advance of
the detonation zone is termed the detonation rate.

FIGURE 1 - 2
EXPLOSIVES BEFORE DETONATION

DETONATOR

FIGURE 1 – 3
EXPLOSIVE PARTIALLY DETONATED

60
TERHAD

TERHAD

DETONATION ZONE UNDETONATED EXPLOSIVE

DETONATION SHOCK ZONE
PRODUCTS CHEMICAL REACTION ZONE

Rate of Detonation

5. The rate of detonation of a given explosive, provided that sufficient initiator or
booster explosive is use, is determined by its degree of confinement and loading
density. If confined only slightly, as by a cardboard or glass tube, a cylindrical column
of high explosive detonates at a lower rate than 12 a heavy steel tube surrounds the
explosive. This is because of the greater loss of energy in directions at right angles to
the axis of the column.

6. This effect is seen also if the diameter of the column of explosive is decreased.
In such case, there is a minimum diameter, also dependent upon degree of
confinement, below which detonation cannot propagate itself through the length of the
column. In practice, detonation rates are determined with columns 1 inch or more in
diameter confined in Shelby steel tubing or as strong a material as the test method
will permit.

7. Decrease in loading density cause decrease in rate of detonation, the
relationship being linear. Each explosive has a characteristic maximum rate of
detonation for a given density, although in the least sensitive explosive is improperly
initiated or has become desensitized, a detonation wave can, in some cases, progress
through the explosive at much less than its normal maximum rate.

8. Although nitroglycerin usually detonates at a maximum rate of about 8,000
meters per second, it can do so at rates as low as 1,500 to 2,000 meters per second.
However, investigation has indicated that not all of the nitroglycerin is detonated in
such cases.

PRINCIPLE CONSIDERATIIONS IN CHOICE OF MILITARY EXPLOSIVE
COMPOSITION

61
TERHAD

TERHAD

9. There is an enormous literature of explosive substances, particularly in the
realm of patents. Some or these substances have never come into practical use, some
have found application in industry, and a relatively small number have been
considered of military value. It will therefore be of interest to consider some of the
principal considerations which enter into the decision to adopt for military use an
explosive or explosive composition.

Availability and Cost

10. Moderm warfare has tended to necessitate the provision of explosive stores in
enormous quantity, consequently all the materials used in those stores, including the
explosives, must be derived from the cheapest possible raw materials, which must be
as readily available as possible and not subject to priority demand from other quarters
(for example, for food or clothing). In the past the very nature of explosives called for
the use of such labour, particularly in the filling operations. Not only is such labour
increasingly costly but, especially in wartime, it is scarce, so that a desirable military
explosive must be as simple as possible to make and as amenable as possible to
mechanical handling in the filling process. In moderm phraseology, the design of a
military store involves ‘value engineering’ and, if they have any competitions, the
explosives to be used in a store are closely scrutinized on grounds of ‘cost
effectiveness’.

Stability

11. Since explosives are metastable chemical systems it is important that natural
processes of degradation (as opposed to the rapid explosive processes induced when
required) shall be slow, strictly limited and prevented from becoming dangerous or
even exploding. To this end it is first necessary that explosives shall be as highly
purified (particularly from residues of acid) as is consistent with economics. There after
they must be stored, whether in bulk or in filled munitions, under conditions which will
be as nearly as possible consistent with the avoidance of degradation, containers and
ammunition empties must be scrupulously clean, storage temperatures must not be
excessive, etc. In general, nitro-compounds (for examples, TNT, RDX) have only a
slow rate of degradation, but this is less true of nitric esters (for example,
nitrocellulose, nitroglycerine) because the degradation of such esters results in the
development of acidity which auto catalyses further degradation. Thus the chemical
conditions of storage of nitric ester systems (for example, cordite) should be mildly
alkaline, but some nitro-compounds (for example, TNT, tetryl) are not favored by
alkalinity, which leads to the formation of by products (nitrolic acids), and it is therefore
not desirable in general to mix such nitrocompounds with nitric esters in explosive
compositions. It is thus important in choosing a military explosive that the processes
of its natural degradation shall be well understood and that practicable means of
inhibiting them shall have been devised.

Resistance to Water

12. Apart from the possible effect of massive quantities of water in impairing the
ignition of an explosive it must be remembered that water, even in vapour form, may

62

TERHAD

TERHAD

initiate degradative processes. In some instances this effect renders otherwise
potentially attractive explosives unusable, thus tetranitrotoluene, which would be more
powerful than trinitrotoluene, readily loses its fourth nitro-group in presence of water
with development of free (corrosive) acid. This it will readily be understood that
explosives for military use, together with all other materials which may be employed
with them in an explosive munitions, should be easily droid and should not be
hydroscopic. Because of its cheapness, ammonium nitrate is a desirable ingredient of
some explosive compositions, but the problem of its hygroscopic is so great that such
composition are not now employed in stores filled in peacetime.

Compatibility

13. The condition of paragraph 22 and 24 are to some extent inter-link with
compatibility, which is the requirement that the explosive should be as non-reactive
as possible, both with material of construction of munitions stores and with other
explosives with which it might be in contact or proximity in such stores. There is of
course, a corollary to this which is that once an explosive has been accepted into
Service. Any future design of store in which it is desired to use that explosive should
not employed new materials of contraction and this includes varnished, sealing
compositions, etc. the computability of which has not been authoritatively is
established, this particularly important now that industry is producing so many
potentially useful new materials. Many instances will be found in subsequent chapters
of important problems of compatibility.
Toxicity

14. Many explosives, because of their chemical structure, are in some degree toxic,
the effects may very from headaches to dermatitis or to damage to internal
membranes. This effects must carefully be studied before an explosive can be
considered for acceptance into service and must obviously be minimal as possible,
even though the hazard can often be much reduce by careful design of the plant in
which the explosive is processed.

Density

15. It is often necessary for reason of the efficiency of an explosive store that the
higher possible density of filling shall be achieved if only because of the problem of
handling and transporting large quantities of munitions of active service, there is also
a pressure to ensure that such munitions are no larger than is required to produce the
desired effects, Thus the greeters possible economy is called for in the space available
in a store for the explosive, and this implies that a desirable characteristic of an
explosive is a good loading density.

Sensitiveness

16. All explosive are sensitive in some degree to the effects of mechanical shock,
friction, heat, etc. and the degree of sensitiveness of each explosive must be fully
assessed and judged in relation to what is already known of the properties of other
explosive in its class (HE, Propellant, initiator, Pyrotechnic).

63

TERHAD

TERHAD

Volatility

17. It is undesirable than an explosive should be volatile or that it should content
volatile substance. If the explosive is itself volatile it may ‘vaporize’ and residences in
undesirable places, and this has been a problem with even such a substance as
nitroglycerine, the vapour pressure at 20ºC is only about 0.0005 mmHg (that of water
at same temperature is 17.5 mmHg) but which has been known to volatize from cordite
in ammunition. On the other hand, some ‘Smokeless powders’ contain tracers of
residual solvent (usually other / alcohol) which may emerge on storage which
consequent change in the ballistic properties of the powder or development of
pressure in filled ammunition. Beside this consideration it is also necessary that high
explosive shall not have melting points so low that when the filled weapon is store in
a hot climate ‘exudation’ takes place, since this may render the store dangerous to
handle or to use. At the same time it is often convenient, from the standpoint of filing
operations, if the explosive can be melted in a vessel heated by low pressure steam.

HEAT OF FORMATION

18. A chemical reaction is always associated with an energy change and the energy
change can be measured most conveniently in heat units. Every chemical compound
has therefore a ‘Heat of Formation’ with is define has the quantity of heat evolved (or
absorbed) when one gram-molecule of the compound is formed from its constituent
element. Heats of formation are conveniently measure in kilogram calories (kal). An
element since it consist of uncombined matter, is assumed to have zero heat of
formation.

19. A compound is classified EXOTHERMIC if formed from its element with the
evolution of heat an it ‘Heat of Formation’ is given a positive sign. Conversely, and

ENDOTHERMIC compound is farmed from its elements with an absorption of heat an
its heat of formation is given to negative sign. Example of ‘Heats of Formation’:

Endothermic Compounds Exothermic Compounds

Leads azide - 907 kal Nitroglycerine + 82.7 kal
Fulminate of mercury - 63.5 kal Picric Acid + 53.5 kal
R.D.X - 21.3 kal T.N.T + 13 kal
C.E. - 9.3 kal Carbon Dioxide + 94.44 kal
Carbon Monoxide + 27.13 kal
Water (liquid) + 67.4 kal
Water (Vapour) + 57.51 kal

20. When a compound decomposes into its elements, there must also be a heat
change this will be equal in magnitude but opposite in sign to its ‘heat of formation’

64

TERHAD

TERHAD

thus on decomposition of 1 gram molecule of lead azide 907 kal of heat will be given
out.

21. In a chemical reaction, the net heat change will be the sum of the heat changes
concerned in the decomposition of the reactants and the formation of the products.
This net heat change it’s called the ‘Heat of Reaction’. As there must be liberation of
heat for an explosion to occur, the heats of formation of the products of the explosion
must be very much greater than those of the original explosive.

22. Endothermic Explosives. When an Endothermic explosive decomposes its
decomposition alone will give a positive contribution to the heat of reaction, ie; heat
will be evolved. Lead AZIDE provides an example of this since no compounds result
from the decomposition:

phN6 ----------------------------Pb + 3N2 ÷ 107 kal.

23. In the decomposition of most explosives, the products include compounds, and
the heat of reaction will thus become the heat of decomposition of the explosive plus
the sum of the heats of formation of the compound products.
24. Exothermic Explosives. When an exothermic explosive decomposes the
decomposition gives a negative contribution to the heat of reaction, ie., heat is
absorbed. However the heat of reaction must be positive if an explosion is to occur
and this is possible if the products of decomposition include exothermic compounds
whose combined heats of formation exceed the heat of decomposition of the
explosive. To take an example, the heat of decomposition of nitroglycerin is 82.7 kal
there will be a net balance of heat only if the combined heats of formation of products
of decomposition exceed + 82.7 kal.

BALANCED AND UNBALANCED EXPLOSIVES

25. A balance explosive is one which contains sufficient oxygen to oxidize, on
detonation or explosion, all the carbon and hydrogen to carbon dioxide and water
respectively, and leave no excess of oxygen. Such an explosive will develop the
maximum heat possible, and therefore power by utilizing the whole heat of formation
of the carbon dioxide and water.
26. Nitroglycerine and ammonium nitrate are examples of explosives processing
an excess of oxygen which is not employed in forming extra exothermic processes.
TNT and most of the true nitro compounds, are examples of unbalanced explosives,
that is, those which process a deficiency of oxygen so that the carbon and hydrogen
are not fully oxidized, the heat developed being therefore, not the maximum possible.

POWER OF AN EXPLOSIVE

27. The ‘power’ of an explosive is measured by determining the work which it will
do when detonated. An early method of obtaining relative values of ‘power’ is due to
Trauzl and is still employed to some extent. A known weight (usually 20g) of the
explosive is placed, with a detonator, in a test-tube-shaped cavity in a standard lead
block and the aperture of the cavity closed with a standard tamping of dry sand. The

65

TERHAD

TERHAD

expansion of the cavity after explosion is measured (by pouring in water from a
graduated vessel) and is compared with the expansion given by the same weight of
picric acid. The standard lead block is 200 mm diameters and 200 mm high and the
axial cavity is 25 mm diameters and 125 mm deep, a good deal of care must be taken
to control the purity of the lead and its rate of cooling on casting. The method gives
misleadingly low results for slow-burning explosives, for example, gunpowder.
28. At this point, it may be remarked that acknowledge of both the power and the
explosive is useful in assessing its likely performance in a military store. The
combination of the two properties is measure of the ‘brisance’ of the explosive, a high
value of which is called for if a shell, bomb or grenade is required to burst to give lethal
fragments, which should not be too small.
29. An interesting point is Mercury of Fulminate which has a low power figure (39).
Its velocity of detonation (V of D) is low (4,500 meters per second). Very sensitive
explosives are thus not necessarily very powerful, whereas quite violent explosives
such as Amatol may be very insensitive to shock or friction.
BURNING TO DETONATION
30. Some explosives may be caused to detonate as the result of initiation by flame,
a fact which sometimes leads to a misconception of the process of detonation. The
probable explanation is that a portion of the explosive explodes and thus imparts
sufficient shock to the remainder of the explosive to set up a detonation wave. It may
be noted that under such circumstances the resulting detonation can be as violent as
that brought about by normal means of initiation. The fact that the shock wave of one
explosive can be transmitted to another in direct contact with its accounts for
explosives, in which detonation is easily set up, being use as initiating agents for the
detonation of other explosives.

66
TERHAD

TERHAD

SEKOLAH SISTEM MATERIEL
INSTITUT LATIHAN PENGURUSAN MATERIEL

TUDM KINRARA

AIRCRAFT BOMBS

GENERAL

1. An aircraft bomb may be defined as a metal case or container filled with an active
agent in the form of high explosives incendiary or chemical substance with such other
components, either incorporate or fitted during preparation of the bomb that will cause
the bomb to function when required.

Glossary of Terms

2. To define the various components of an aircraft high explosive and where
applicable, an incendiary or practice bomb, the following terms are used:

a. Body. The main casting which may be cast forged or fabricated steel
construction, varying in thickness according to the class of bombs. The body of
practice bombs may be steel or included plastic and the body of incendiary bombs
are of magnesium alloy.

b. Main Filling. The comparatively insensitive explosive content of the bomb.

c. Fusing Well. A metal tube fitted into the nose and tail end of the bomb body to
receive an adaptor exploder.

d. Adaptor Exploder. A relatively insensitive explosive composition in pallet form,
which forms a part of step up explosive train when fitted to the fuzing well of the
bomb.

e. Nose or Tail Fuse. Detonating devices when fitted to the adaptor booster in a
bomb, to complete the step up explosive train required to explode the main filling
of the bomb.

f. Transit Flug. As crew plug that screws into the fuzing well. Used to exclude dirt
and moisture from the well during transit and storage.

g. Transit Base. A protective metal cover attached to the base of a bomb during
storage and transit.

h. Tail Unit. A metal tail with fixed or extensible fins, that mayor may or not
incorporate an arming mechanism. Its purpose is to stabilize the bomb during it's
flight to the target.

67

TERHAD

TERH

HAD

6
TERH

64
HAD

TERHAD

FUZING WELL
FUZING WELL

TRANSIT PLUG TRANSIT BASE

Operation

3. A characteristic of an HE filling is it's insensitivity to Ordinary shock or heat.To effect
denotation it is necessary to employ a train of explosive gradually increasing in
sensitivity, usually three stages

a. Initial Charge - Detonator

b. Intermediate Charge - CE Pallets

70
TERHAD

TERHAD

c. Main Filling - Amatol, RDX,TNT etc

Bomb Classification

4. Aircraft bomb are grouped into categories or classes, eg:

a. High Explosive Bomb

b. Incendiary Bomb

c. Practice Bombs.

5. High Explosive Bomb from the largest group and are identified as follows:

a. Armour Piercinq (AP) Bomb - These bombs are constructed to penetrate
heavily armored targets, without breaking-up occurring during penetration.
The nose is solid heavy case. The fillings are of a very insensitive to shock
and friction, to prevent the possibility of premature detonation of the bomb
before penetration is achieved. E.g. BAP 10065E.

BAP 100-65E

b. General Purpose (GP) Bombs - The bomb in this range are designed
to streamlined contour and are thick walled having a charge/weight ratio of
approximately 33%. Provide with nose or/and tail fusing positions.

c. Medium Capacity (MC) Bombs - Developed because of the need. For
Increased explosive content in bombs for general operational use. The wall of
the bomb body reduced in thickness and adopting a parallel - sided shape.

d. Fragmentation Bombs - Restricted to bombs of approximately 20 Ibs
in weight. For use as an anti personnel weapon.

71

TERHAD

TERHAD

e. Practice Bombs - Used for both day or night bombing training against
varying types of targets.

AIRCRAFT LOW DRAG GENERAL PURPOSE (LDGP) BOMB MK 80 SERIES

Introduction

6. Number of different types of dumb bombs have been developed from World
War 1 until today, and they are typically classified by their weight. A common
type is the MK 80 series developed originally by the US Navy and now also
used by the many airforce world wide.

7. The Low-Drag, General-Purpose (LDGP) currently in use are the LDGP Mk 80
Series. The specifications for the individual bombs are listed below. The basic
difference between the bombs listed below is their size and weight.

8. The Mk 80 Series or family includes the (see figure 4.1):

a. Mk 81, weighing 250 lb (113 kg),
b. Mk 82, weighing 500 lb (227 kg),
c. Mk 83, weighing 1,000 lb (454 kg), and
d. Mk 84, weighing 2,000 lb (907 kg).

9. The current uses in our RMAF Services are the Mk 82, the Mk 83, and the Mk
84.

10. In the US munitions designation system, unguided bombs like these are
typically denoted by the term BLU for Bomb Live Unit. For example, the Mk 82
and 83, with minor changes, are also known as the BLU-111 and BLU-110
while a close relative of the MK 84 is the BLU-109. Other nations have also
developed their own equivalents to the MK 80 family, such as the United
Kingdom and Russia that use 250 kg and 500 kg un-guided bombs.

11. GP bombs can be made into a Semi-Armor Piercing Bomb by retaining the
original Nose Closure Plug and installing only a Tail Fuze. This configuration
will penetrate medium hard targets. This bomb type was given the designation
GP, because of its versatility. GP bombs are all cylindrical in shape and are
equipped with conical fins or retarders. They are adapted for both nose and tail
fuzes to ensure reliability and to cause the desired effects.

72

TERHAD

TERHAD

73
TERHAD

TERHAD

74
TERHAD

TERH

HAD

6
TERH

69
HAD

TERHAD

AIRCRAFT BOMB 500 LB MK 82 LDGP

Introduction

12. Low-Drag, General-Purpose (LDGP), free-fall bombs are used in most bombing
operations. Their cases (bomb body) are aerodynamically designed, relatively
light, and approximately 45% of their weight are made of explosives. General-
Purpose Bombs may use both Nose and Tail Mechanical or Electric Fuzes and
Conical or Snakeye Fins.

Description

13. Aircraft Bomb, 500 lb Mk 82 LDGP is similar in design to other GP Bomb, but
is streamlined and consequently is thinner and longer. The bomb is used with
either the Conventional Fin/Conical Fin (GP) or the Mk 15 Snakeye Fins
Assembly. The bomb can be fuzed option on the nose and tail or either ones in
their Low Drag or High Drag Mode, depending on the operational requirement.
There are 4 types of MK 82, but only 2 types were employed in our inventories,
there are:

a. MK 82 Mod 1 and 2 High Explosive (HE), used by RMAF
b. MK 82 Mod 2 (HE) and High Explosive Substitute (HES)
c. MK 82 Mod 2 High Explosive Substitute (HES)
d. MK 82 Mod 1 Empty (Inert), used by RMAF

14. Bomb Body. The bomb body is slender cylindrical Steel Casting with low drag
characteristics. An interior Bituminous Lining provides partial thermal protection
in the event of a fire. The main filling is 83.5 kg H-6 explosive for the MK 82
mod 2 (HE) and 87.1 kg Tritonal 80-20 explosive for the Mk 82 Mod 1 (HE).

15. Fuze Wells. The bomb body is designed with a Nose and Tail Fuze Well.
These wells are internally threaded to receive either mechanical or electric fuzes (Fuze
Charging Circuit). The forward and aft charging tubes are installed at the factory and
are contains the Electric Fuze Wire Harness. When Electric Fuzing is used, the Wire
Harness provides a path for the charging current from the FuzeCharging Receptacle
to the Nose and Tail Fuze Wells. The nose fuze well is a 76.2 mm diameter cylindrical
housing screwed into the nose of the bomb to accept the Nose Adaptor Exploder
before fuzing.

16. Base Plug And Tail Fuze Well. The base plug is a cylindrical steel plate screwed
into the base of the bomb after it is has been filled. Into the centre of the base
plug is screwed the tail fuze well which similar in size to the nose fuze well.

17. Charging well and conduits. The charging well is a threaded recess in the side
of the bomb body. From this recess two conduits run through the centre of the
bomb, one to each of the fuzing well. The Charging Tube and Conduits are
used to carry the Electrical Harness of an Electrically Armed Fuze.

77

TERHAD

TERHAD

MK 82 LDGP Bomb illustrations and cross section
18. Functioning. When the bomb is released from the aircraft, the following action

takes place:
a. The arming wires are withdrawn allowing the fuze arm and in case of high drag tails,

the tail unit is operated.
b. The fuze arming mechanism operates, and after a preset time delay, the fuzes become

fully armed.
c. The bomb impacts with the target causing the fuze to detonate.
d. The fuze detonation with the target causing the fuze to detonates.
19. Identification. The overall color of the bomb body is Olive Drab with 76 mm

wide Yellow Filling Band around the nose. Information pertaining to the
manufacture of the bomb is stenciled on the body in 13 mm Yellow Letters.
The High-Explosive (HE) filler of the Bomb (H-6) is identified by the yellow
stenciled nomenclature on the bomb body and Yellow Band (s) around the
nose.

78
TERHAD

TERHAD

Mk 80 series LDGP Aircraft Bomb Identification (NATO Standard)

Bomb A/C 500 lbs GP MK82
SPECS
Class: 500 lb. General Purpose Bomb, Blast/Fragmentation
Guidance: Ballistic Weight:
241 kg / 500 lbs.
Length: 2.21 m / 66.15 in.
Diameter: 10.75 in.
Warhead: 500 lbs.
Explosive: 89 kg / 192 lbs Tritonal, Minol II, or H-6 Fuse:
Variety for nose and tail.
Stabilizer: MAU-93/B, BSU49/B AIR, MK-15 Snakeye
Aircraft: A-10A, B-1B, B-2, B-52, F-4G, F-15A-E, F-16A-D, F-111D-F, F-117A

79
TERHAD

TERHAD
Main filling: 83.5 kg of H-6 explosive for the MK 82 Mod 2, and 87.1kg of TRITONAL
80-20 explosive for the MK 82 Mod 1.

80
TERHAD