A combustion light-gas gun (CLGG) is a projectile weapon that utilizes the explosive force of low
molecular-weight
The molecular mass (''m'') is the mass of a given molecule: it is measured in daltons (Da or u). Different molecules of the same compound may have different molecular masses because they contain different isotopes of an element. The related quanti ...
combustible gases, such as
hydrogen
Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic, an ...
mixed with
oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...
, as propellant. When the gases are ignited, they burn, expand and propel the projectile out of the
barrel
A barrel or cask is a hollow cylindrical container with a bulging center, longer than it is wide. They are traditionally made of wooden staves and bound by wooden or metal hoops. The word vat is often used for large containers for liquids, ...
with higher efficiency relative to
solid propellant
A propellant (or propellent) is a mass that is expelled or expanded in such a way as to create a thrust or other motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, the e ...
and have achieved higher
muzzle velocities in experiments. Combustion light-gas gun technology is one of the areas being explored in an attempt to achieve higher velocities from
artillery
Artillery is a class of heavy military ranged weapons that launch munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during siege ...
to gain greater range. Conventional guns use solid propellants, usually
nitrocellulose
Nitrocellulose (also known as cellulose nitrate, flash paper, flash cotton, guncotton, pyroxylin and flash string, depending on form) is a highly flammable compound formed by nitrating cellulose through exposure to a mixture of nitric acid and ...
-based compounds, to develop the chamber pressures needed to accelerate the projectiles. CLGGs' gaseous propellants are able to increase the propellant's
specific impulse
Specific impulse (usually abbreviated ) is a measure of how efficiently a reaction mass engine (a rocket using propellant or a jet engine using fuel) creates thrust. For engines whose reaction mass is only the fuel they carry, specific impulse i ...
. Therefore, hydrogen is typically the first choice; however, other propellants like
methane
Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The relative abundance of methane on Eart ...
can be used.
While this technology does appear to provide higher velocities, the main drawback with gaseous or liquid propellants for gun systems is the difficulty in getting uniform and predictable ignition and muzzle velocities. Variance with muzzle velocities affects precision in range, and the further a weapon shoots, the more significant these variances become. If an artillery system cannot maintain uniform and predictable muzzle velocities it will be of no use at longer ranges. Another issue is the survival of projectile payloads at higher accelerations.
Fuze
In military munitions, a fuze (sometimes fuse) is the part of the device that initiates function. In some applications, such as torpedoes, a fuze may be identified by function as the exploder. The relative complexity of even the earliest fuze d ...
s, explosive fill, and guidance systems all must be "hardened" against the significant acceleration loads of conventional artillery to survive and function properly. Higher velocity weapons, like the CLGG, face these engineering challenges as they edge the boundaries of firing accelerations higher.
The research and development firm UTRON, Inc is experimenting with a combustion light-gas gun design for field use.
The corporation claims to have a system ready for testing as a potential long-range naval fire support weapon for emerging ships, such as the
Zumwalt-class destroyer
The ''Zumwalt''-class destroyer is a class of three United States Navy guided-missile destroyers designed as multi-mission stealth ships with a focus on land attack. It is a multi-role class that was designed with a primary role of naval gunfir ...
. The CLGG, like the
railgun
A railgun or rail gun is a linear motor device, typically designed as a weapon, that uses Electromagnet, electromagnetic force to launch high velocity projectiles. The projectile normally does not contain explosives, instead relying on the proj ...
, is a possible candidate technology for greater ranges for naval systems, among others. UTRON has built and tested 45mm and 155mm combustion light-gas guns.
See also
*
Light-gas gun
The light-gas gun is an apparatus for physics experiments. It is a highly specialized gun designed to generate extremely high velocities. It is usually used to study high-speed impact phenomena (hypervelocity research), such as the formation of ...
*
Scram cannon
A ram accelerator is a device for accelerating projectiles or just a single projectile to extremely high speeds using jet-engine-like propulsion cycles based on ramjet or scramjet combustion processes. It is thought to be possible to achieve non ...
References
https://apps.dtic.mil/dtic/tr/fulltext/u2/a462130.pdf UTRON 2006 Test Report
Artillery by type
Ballistics
Emerging technologies
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