Everything about Projectiles totally explained
A
projectile is any object propelled through space by the exertion of a force, which ceases after launch. In a general sense, even a
football or
baseball may be considered a projectile. It can cause damage (
injury,
property damage) to a person, animal or object it hits, depending on factors including
size,
shape,
speed and
hardness. Accordingly, in practice most projectiles are designed as
weapons.
Motive force
Arrows,
darts,
spears, and similar weapons are fired using pure mechanical force applied by another solid object; apart from
throwing without tools, mechanisms include the
catapult,
slingshot, and
bow.
Other weapons use the compression or expansion of gases as their motive force.
Blowguns and
pneumatic rifles use compressed gases, while most other
guns and
firearms utilize expanding gases liberated by sudden chemical reactions.
Light gas guns use a combination of these mechanisms.
Railguns utilize electromagnetic fields to provide a constant acceleration along the entire length of the device, greatly increasing the
muzzle velocity.
Some projectiles provide propulsion during (part of) the flight by means of a
rocket engine or
jet engine. In military terminology, a
rocket is unguided, while a
missile is
guided. Note the two meanings of "rocket": an
ICBM is a missile with rocket engines.
Non-kinetic effects
Many projectiles, for example
shells, contain an explosive charge. With or without explosive charge a projectile can be designed to cause special damage, for example fire (see also
early thermal weapons), or poisoning (see also
arrow poison).
Kinetic projectiles
Projectiles which do
not contain an explosive charge are termed
kinetic projectile,
kinetic energy weapon,
kinetic warhead or
kinetic penetrator. Classic kinetic energy weapons are blunt projectiles such as
rocks and
round shot,
pointed ones such as
arrows, and somewhat pointed ones such as
bullets. Among projectiles which don't contain explosives are also
railguns,
coilguns,
mass drivers, and
kinetic energy penetrators. All of these weapons work by attaining a high
muzzle velocity (
hypervelocity), and
collide with their objective, releasing
kinetic energy.
Some kinetic weapons for targeting objects in
spaceflight are
anti-satellite weapons and
anti-ballistic missiles. Since they need to attain a high velocity anyway, they can destroy their target with their released kinetic energy alone; explosives are not necessary. Compare the energy of
TNT, 4.6 MJ/kg, to the energy of a kinetic kill vehicle with a closing speed of 10 km/s, which is 50 MJ/kg. This saves costly weight and there's no
detonation to be precisely timed. This method, however, requires direct contact with the target, which requires more accuracy.
With regard to anti-missile weapons, the
Arrow missile and
MIM-104 Patriot have explosives, but the
Kinetic Energy Interceptor (KEI),
Lightweight Exo-Atmospheric Projectile (LEAP, see
RIM-161 Standard Missile 3), and
THAAD being developed don't (see
Missile Defense Agency).
See also
Hypervelocity terminal ballistics,
Exoatmospheric Kill Vehicle (EKV).
A kinetic projectile can also be dropped from aircraft. This is applied by replacing the explosives of a regular bomb for example by concrete, for a precision hit with less
collateral damage. A typical bomb has a mass of 900 kg and a speed of impact of 800 km/h (220 m/s). It is also applied for training the act of dropping a bomb with explosives.
(External Link
) This method has been used in
Operation Iraqi Freedom and the subsequent military operations in
Iraq by mating concrete-filled training bombs with
JDAM GPS guidance kits, to attack vehicles and other relatively "soft" targets located too close to civilian structures for the use of conventional
high explosive bombs.
A
kinetic bombardment may involve a projectile dropped from Earth orbit.
A hypothetical kinetic weapon that travels at a significant fraction of the speed of light, usually found in science fiction, is termed a
relativistic kill vehicle (RKV).
Typical projectile speeds
| Projectile |
Speed (m/s) |
(ft/s) |
(mph) |
a href=http://Kinetic_energy.totallyexplained.com title="Kinetic energy - Totally Explained">Kinetic energy |
| object falling 1 m |
4.43 m/s |
14.5 ft/s |
9.9 mph |
9.8 J/kg |
| object falling 10 m |
14 m/s |
46 ft/s |
31 mph |
98 J/kg |
| thrown club (weapon) (expert thrower) |
40 m/s |
130 ft/s |
90 mph |
800 J/kg |
| object falling 100 m |
45 m/s |
150 ft/s |
100 mph |
980 J/kg |
| refined (= flexible) atlatl dart (expert thrower) |
45 m/s |
150 ft/s |
100 mph |
1000 J/kg |
| 80-lb-draw pistol crossbow bolt |
58 m/s |
190 ft/s |
130 mph |
1.7 kJ/kg |
| paintball fired from marker |
91 m/s |
300 ft/s |
204 mph |
4.1 kJ/kg |
| 175-lb-draw crossbow bolt |
97 m/s |
320 ft/s |
217 mph |
4.7 kJ/kg |
| air gun pellet 6 mm BB |
100 m/s |
328 ft/s |
224 mph |
5 kJ/kg |
| rifle bullet 4.5 mm |
150 m/s |
492 ft/s |
336 mph |
11 kJ/kg |
| air gun pellet (conventional maximum) |
244 m/s |
800 ft/s |
545 mph |
29.8 kJ/kg |
| 9x19 mm (bullet of a pistol) |
340 m/s |
1116 ft/s |
761 mph |
58 kJ/kg |
| 12.7x99 mm (bullet of a heavy machine gun) |
800 m/s |
2625 ft/s |
1790 mph |
320 kJ/kg |
| 5.56x45 mm (standard bullet used in many assault rifles) |
920 m/s |
3018 ft/s |
2058 mph |
470 kJ/kg |
| 125x1400 mm (shell of a tank) |
1700 m/s |
5577 ft/s |
3803 mph |
1.4 MJ/kg |
| 2kg Tungsten Slug (from Experimental Railgun) |
3000 m/s |
9843 ft/s |
6711 mph |
4.5 MJ/kg |
| ICBM reentry vehicle |
up to 4 km/s |
up to 13000 ft/s |
up to 9000 mph |
up to 8 MJ/kg |
| projectile of a light gas gun |
up to 7 km/s |
up to 23000 ft/s |
up to 16000 mph |
up to 24 MJ/kg |
| satellite in LEO |
8 km/s |
26000 ft/s |
19000 mph |
32 MJ/kg |
| Exoatmospheric Kill Vehicle |
closing speed roughly 10 km/s |
~33000 ft/s |
~22000 mph |
~ 50 MJ/kg |
| projectile (for example space debris) and target both in LEO |
closing speed 0 - 16 km/s |
~53000 ft/s |
~36000 mph |
~ 130 MJ/kg |
Miscellaneous
Ballistics analyze the projectile
trajectory, the forces acting upon the projectile, and the impact that a projectile has on a target. A
guided missile isn't called a projectile.
An explosion, whether or not by a weapon, causes the debris to act as multiple high velocity projectiles. An explosive weapon, or device may also be designed to produce many high velocity projectiles by the break-up of its casing, these are correctly termed
fragments.
The term projectile also refers to
weapons or any other objects thrown, shot or otherwise directed to enemies in video games or computer games.
Projectile is also the name of an annual anarchist film festival based in Newcastle UK *
(External Link
)Further Information
Get more info on 'Projectiles'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://projectile.totallyexplained.com">Projectile Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |