A combustion light-gas gun (CLGG) is a projectile weapon that utilizes the explosive force of low molecular-weight combustible gases, such as

hydrogen Hydrogen is a chemical element; it has chemical symbol, symbol H and atomic number 1. It is the lightest and abundance of the chemical elements, most abundant chemical element in the universe, constituting about 75% of all baryon, normal matter ...

mixed with

oxygen Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), non ...

, 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 stave (wood), staves and bound by wooden or metal hoops. The word vat is often used for large containers ...

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 another motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, th ...

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 consists of ranged weapons that launch Ammunition, munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during sieges, and l ...

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, such as a rocket engine, rocket using propellant or a jet engine using fuel, generates thrust. In general, this is a ratio of the ''Impulse (physics), ...

. 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 abundance of methane on Earth makes ...

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 its function. In some applications, such as torpedoes, a fuze may be identified by function as the exploder. The relative complexity of even the earliest fu ...

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. The class was designed with a primary role of naval gunfire support and seconda ...

. The CLGG, like the

railgun A railgun or rail gun, sometimes referred to as a rail cannon, is a linear motor device, typically designed as a ranged weapon, that uses Electromagnet, electromagnetic force to launch high-velocity Projectile, projectiles. The projectile norma ...

, 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.

References

https://apps.dtic.mil/dtic/tr/fulltext/u2/a462130.pdf UTRON 2006 Test Report Artillery by type Ballistics {{firearms-stub

See also

References