LRG224 Multipurpose Railgun Artillery System

Though it certainly would have been welcome among the various special weapons projects of Project TEMERITY, the LRG224 Multipurpose Raingun Artillery System was developed separately by the UNSC Army Ordnance Corps, originally as a heavy anti air artillery piece, allowing defending ground forces far superior capabilities against invading aircraft and warships. Though certainly effective against smaller craft, such as fighters and dropships, and equally effective at providing indirect fire support against ground targets, it was primarily designed to hammer the larger targets presented by enemy warships, bringing their shields down to allow missiles and fighters to damage the vulnerable hull underneath. Though research began in 2545, the first production units only entered service in 2552, seeing deployment in the Minorca, Reach and Earth combat theatres, but would see far wider service in the post-war period, established as a cheaper alternative to Orbital Defence Platforms for smaller colonies. A number of variants would be developed for specialisation niches, but the basic Chernabog artillery piece would become a favourite among UNSC Army artillery regiments.

Development
As the battle for the Outer Colonies raged on for eleven years, patterns began to emerge. For the most part, the UNSC held the advantage on the ground - they had an intimate knowledge of the terrain, especially in urban popution centres, where Covenant troops had difficulty navigating. Moreover, they had a superior understanding of neccessary tactics and strategies for ground and atmospheric combat than their Covenant counterparts. If the war had been entirely a planetary affair, it is likely it would have become a stalemate. Ultimately, the reason for the Covenant's success, has been their warships. Even with tactical superiority on the ground, the UNSC has never been able to counter their warships to any great effect. It has always been a relatively simple matter for the Covenant to smash through UNSC orbital defences and rain plasma and laser fire onto the vulnerable human forces. With such a technological advantage, the Covenant's gains have been swift and devastating.

Beginning in 2536, the year the last of the Outer Colonies fell, the UNSC Army began searching for means by which they could counteract the superiority of enemy warship support. Various systems were tested, with varying degrees of success - electromagnetic pulse weapons, improved nuclear missiles, and even some unorthodox approaches such as the UC709 Unmanned Combat Aerian Vehicle, intended to simply slam a nuclear warhead into the ship - but all met with significant problems, especially with UNSC Research and Development funding being poured into the Naval Special Warfare, leaving little for other branches. In 2542, Colonel Brian Rawiri proposed that the Army use a pre-existing concept, but use advances in technology since its development - ground-based mass drivers.

Railgun technology has been commonplace since the late twenty first century, but its uses have been limited by financial costs, power requirements, technical sophistication, and replacement by more efficient equipment. While the application of mass drivers as weapons has always been a focus of the military, its most common use has been as civilian cargo launch systems, accelerating freight into orbit - in the early twenty fifth century, most of these were rendered obsolete by the adoption of space elevators on even outer colonies. The navy had continued to develop the concept of magnetically acclerated projectile weapons for their ship-based Magnetic Accelerator Cannons, but the common use of nuclear weapons, ship-launched missiles and THOR strikes, in the minds of Army and Marine commanders, rendered conventional artillery obsolete, and research was eventually abandoned totally. When the Army began investigating a counter to Covenant warships, the subject was raised again, and deemed the best approach, using off-the-shelf technologies to reduce development cost. Nevertheless, it would still take seven years since the start of development for the first prototypes to see combat, and it would only enter service fully after the Human-Covenant War.

The actual development was a cooperative effort between researchers from the Army Ordnance Corps, and Bellum Aerospace Industries. Though primarily a starship supplier, BAI had been looking at moving into other areas of the military industry, and saw their chance with the LRG224. Sierra Space Systems attempted to counter BAI by offering the GAA-7, a self-propelled artillery gun, but it was deemed unsufficient for the Army's needs and summarily rejected. Over the next seven years, BAI and the Army would develop and produce the concept for the LRG224, utilising advances in railgun design made after 2490 to produce a compact but powerful artillery platform capable of engaging a variety of different threats - enemy aircraft and ground targets, but especially warships.

Combat Service
Despite still being in the prototype phase, seven LRG224X MRAS guns were set up on Minorca during the preparations for the colony's defences, intended as a field test. In this role, the guns proved themselves quite capable, accounted for the CCS Chaste Pursuit, and throughout the rest of the campaign would account for sixty six enemy fighters and dropships, as well as providing indirect fire support for Army and Marine ground operations. Deemed a success, their performance at Minorca saw FLEETCOM give Bellum Aerospace Industries their approval to move into mass-production, and its Reach factories began work on the first production batch. The initial production models were shipped to Minorca in January, 2552, to continue to support UNSC operations in the combat theatre, while another sixty were requisitioned by UNSC Sol CENTCOM for the defence of HIGHCOM and the Security Committee.

The invasion of Reach by the Fleet of Particular Justice put a stop to that, with the BAI production facilities on the planet destroyed in the opening wave by tactical strikes by Banshee and Seraph bombing runs. Fourteen managed to survive the initial attack, and would prove effective in the UNSC's attempts at retaking Elysium, but were eventually destroyed by an Energy Projector fired by the orbiting Assault Carrier Bringer of Truth. The forty artillery pieces from the Minorcan campaign were among the equipment brought back by the UNSC 30th Fleet, and were requisitioned by CENTCOM to fortify UNSC Earth Theatre Command Headquarters.

After the war, production of the design would resume as BAI became one of the major military suppliers for the UNSC, even more so after the collapse of Sierra Space Systems. Though the entire second production line, and most of the first, had been destroyed in combat, the design had still proven an extremely effective one. Though originally operated by the Army, a dedicated indirect-fire variant, the LRG224D, was adopted by the UNSC Marine Corps for extreme long range fire support missions. The artillery would see use in the Megiddo and Middangeard theatres of combat, once again proving their effectiveness by repelling assaults on both worlds, forcing the enemy to resort to conventional invasion tactics, against which the UNSC had a distinct advantage.

Design
A its most basic, the LRG224 uses two rails composed of powerful electromagnets to accelerate a ferrous projectile to supersonic velocities

Variants

 * XLRG224 MRAS - the intial prototype model, the XLRG224 proved itself not only extremely effective at its intended role, but also extremely flexible, able to fulfill additional anti-air and indirect-fire roles. While it lacked the high rate of fire of conventional flak cannons employed for anti-air defence, its extremely high accuracy made it extremely effective, especially against the larger Seraph fighters, and the slower Spirit and Phantom dropships. It proved even more devastating against ground targets, the supersonic shells providing UNSC ground forces with fire support from extreme distances.
 * LRG224A1 "Czernobog" MRAS - a 2552 update to the original design, the A1 variant made improvements to the fusion reactor and to the barrel, improving its longevity and durability. Otherwise, it possessed similar characteristics to the original.
 * LRG224A2 "Czernobog II" MRAS - the A2 was an extensive update of the original design, improving the effectiveness and efficiency of the railgun itself, and improving the power supply dramatically. Introduced in 2556, it would eventually become the most common variant.
 * LRG224B "Abaddon" MRAS - a dedicated anti-air artillery piece introduced in 2554, the B variant doubles the rate of fire to improve fire output against enemy aircraft, though at the expense of kinetic force - though, at the velocities the shells move at, it is still more than sufficient to shred even a Seraph to pieces.
 * LRG224C "Samael" MRAS - a dedicated indirect fire support weapon, the C variant features few modifications of the basic design, with the largest differences in the targeting systems. The C variant can fire either the more common ferric-tungsten shells, or a modified ferric-tungsten shell with a depleted uranium tip for anti-armour engagements.
 * LRG224D MRAS - though classed as a different variant, the D is largely a carbon copy of the C, operated by the Marine Corps.

Quotes

 * "The thing is so huge it has to be towed by a train. If there isn't a railway in range, then it can't really get there - but of course, everything is within its range!"
 * "Wouldn't they make massive targets? They have huge firepower, but they're also not exactly compact, and would nmake vital targets for the enemy. If they see them, of course."
 * "I was stationed near them on Minorca - two salvoes from two units, and it brought a Covenant Battlegruiser crashing down! It may not be a Super MAC, but it certainly gets the job done!"