HALOS (Hyboria)

Rifle, 48-inch, M8
3 examples shown on Barbette Mount M13
Type	Low-orbital hypervelocity asteroid interception and air and ballistic missile defense
Place of origin	Hyboria
Service history
In service	1987-
Used by	Hyboria
Wars	Omandan Continental War
Production history
Designer	Dr. William Atkinson
Designed	1970
Manufacturer	Various
Unit cost	20 Billion dollars
Produced	1982-1990
No. built	8
Specifications
Shell weight	12 tonnes
Caliber	1,200 mm (47 in)
Elevation	+80° -15°
Traverse	360°
Rate of fire	1 round every 5 minutes
Muzzle velocity	6 km/s (20,000 ft/s)
Effective firing range	1,500 km (930 mi)
Maximum firing range	2,000 km (1,200 mi)
References

The Hyborian Anti Low Orbital System, also known as HALOS or by its project name, Project Stonehenghe is a low-orbital hypervelocity asteroid interception and strategic air and ballistic missile defense system developed and built in Hyboria. The system was developed initially to combat low-orbital debris and asteroid impacts following the planetfall of the Ulysses Asteroid in 1913 and the subsequent years following. During the events of the Omandan Continental War its use as an anti-air and missile defense system was also unveiled. Upon entry in early 1987, the HALOS was used against a large formation of Transnapistani bomber aircraft using a low-yield nuclear munition, the existence of which had been kept a secret to the world. The guns would go on using their standard ammunition for engagements until the 1994 nuclear exchange. Then the system would also show its use as a ballistic missile defense system, shooting down Transnapistani MRVs with their low-yield nuclear shells, greatly reducing effectiveness of the nuclear strike on Hyboria.

It is the largest artillery gun in the world, uses the largest supercomputer in the world and is the only major operational light-gas gun in service in the world. It was developed by Dr. William Atkinson, who had been developing the system from its inception since the 1960s. All eight of the HALOs guns are located at the Sandy Orbital Defense Base, formerly known as Sandy Air Force Base, in the Great Sandy Desert in the state of Hatties. The crew of a single gun is roughly 350 personnel, located on the gun, and in the adjacent fire control building.

Development and design

Main article: Ulysses Impact Event

16" SLOG test fire, 1969

On April 16th, 1913, the Ulysses Asteroid, named after the physicist Samuel Ulysses who had discovered the asteroid a mere twenty days before it began its breakup over Annwynn. The asteroid is suspected to have been loosely held together and made up mostly of frozen water, as once it began to come into orbit with Annwynn, it broke up almost instantly. The asteroid is estimated to be roughly 31 kilometers (19.2 mi) in diameter, and made up mostly of carbon and water, with large amounts of sulfur, arsenic, lead, and mercury present as well. It was possibly the size of the first asteroids that impacted Annwynn millions of years ago, causing the mass-extinction events of the time. However instead the asteroid began to break up upon entry into orbit and even more as these fragments began to push through the atmosphere. Unlike the asteroids from millions of years ago the Ulysses Asteroid came towards Annwynn at a very shallow angle, allowing for much of the fragments to break off and enter into the rotation and set into a slow descent onto the planet.

The impacts were world-wide, however the majority took place over the continent of Hyboria. The resulting impacting fragments ranged between a few meters to the largest being over 300 meters. The largest of these fragments exploded over the capital of the Republic of Jothain, Harthampton. The resulting explosion is estimated by modern experts to be over 15 megatons of TNT in strength, equivalent to the nuclear weapons used by the Hyborian Federation in the later stages of the Omandan Continental War. Much of the city was destroyed, with over 100,000 people killed in the initial blast, with tens of thousands more dying over the next few days.

The impact devastated the continent, and would be the catalyst to the next 30 years of conflict on the continent. While the various nations began to war with one another, the fragments of the asteroid remained in orbit about Annwynn. While dozens of fragments impacted onto Annwynn, the majority of the remnants of Ulysses Asteroid remained in orbit, which was discovered in the years following. Study of these fragments was put on hold during the outbreak of war, which would not be resumed until the end of hostilities in 1921. Research resumed again, as occasional fragments would descend onto Annwynn. Due to the nature of the Ulysses fragment’s orbit, the gravitational pull would tend to bring down these fragments onto Hyboria or around it, leaving much of the world unscathed as a result.

Outbreak of the 3rd Hyborian Continental War in 1939 again put direct research on hold, however the field of rocketry and radar greatly expanded, which would go to help research on the asteroid in the 1950s. At the end of the 3rd HCW, Wastrouland-born aerospace engineer and space architect Abraham Busch was given the mission of creating a system to intercept these fragments before they could impact Hyboria. During the war and the years beforehand, dozens of impacts had occurred, some resulting in large losses of life, displacement of people, and untold amounts of infrastructure damage. Busch also was instrumental in starting the Hyborian space program.

However during this time, William Atkinson, a relatively young engineer who had just gotten his doctorate in 1953, began to work for the Hyborian Aerospace Administration. With experience working for the Hyborian Armed Forces developing high-velocity, long ranged artillery guns, Atkinson began to work for HAA to use his designs to develop a cost-effective way to launch satellites into orbit using large caliber guns. Known as Satellite Launching Orbital Gun or SLOG, it began with small caliber guns in the late 1950s, the project would come to its peak in the mid-1960s when they would fire guided 16” shells at incredibly high speeds.

Atkinson attempted to push the idea of using the new 16” gun to intercept the fragments but was met with great resistance from Busch and other researchers from the HAA. Atkinson attempted to push it further, however when funding for his program was threatened, Atkinson used his connections to the Armed Forces to try to pitch the idea to them. While apprehensive at first, Atkinson also secretly talked about the use of low-yield nuclear devices in an anti-aircraft role from these new guns, which made the Armed Forces much more receptive to the idea.

Funding for Atkinson’s project was increased greatly, and by the 1970s he had built larger guns, 240mm and 520mm respectively. Rounds went higher and faster than ever, however Atkinson suspected he was reaching the peak of capability of conventional ammunition and powder design, and began to look into an exotice proposal using various types of gasses, later known as a light-gas gun. By this time, the costs of Busch’s missile-based interception systems had been deemed to costly to fund, and had been moved to interception of missiles rather than asteroids.

By 1978, Atkinson and the Army Ballistic Test and Research Center had built the first operable light-gas gun, a 37mm gun known as the XM1. Two more of these guns would be built and would be tested well into the 1990s. Following experiences with the XM1, the XM2, XM3 and XM4 would be built. Caliber of these guns would range from 57mm, 75mm, and 155mm. By the XM4, which was 155mm, velocities were being achieved that far outstripped that of which had been achieved by the SLOG program some 10 years beforehand. The first, mostly accidental, interception occurred in 1980, when the XM4 gun intercepted a roughly 50m wide fragment, breaking it up and allowing it to burn up upon entry. This accidental proof of concept was used by Atkinson to sell his idea to the population and the government, which until then had started to grow unhappy with the lack of results and the tens of millions of dollars used in its development.

In 1980 Atkinson began to design an even larger gun, known as the Ultra-Huge Fragment Interception Gun Platform, the design was to be over a meter in caliber and proposed his idea to the Federal Presidium, who almost immediately threw him out over the projected costs of a single gun, let alone his idea of an 8-gun battery located in the middle of the country. In 1982 however astronomer Stanley Booth and some 40 other astronomers, published a study showing that within the next 30 years, the rate of impacts from the Ulysses fragments would quadruple, with many of the larger fragments possibly coming down. The study published also over went the possible outcome of the impacts, which included a new famine, civil war, and a breakdown like that in 1913-1914. Losses were expected to be even worse than in 1913, due to the density of urban living that had happened as a result of further industrialization.

Funding for the gun program was secured not too long after the study was published, following major public backlash.

The guns, designated as Rifle, 48-inch, M8. A combustion light-gas gun, the barrel is a two part construction, the pressure chamber where the light gasses are collected before being detonated is made of a steel and columbium alloy, while the barrel itself that the projectile goes down is a stainless steel with a chrome-lining.

The guns themselves would be mounted on a large barbette mount, designated Barbette Mount M13, the mounts feed into a hardened magazine that conveys ammunition into the gun. An underground internal rail system connects all the guns and other underground systems, a larger central magazine is located elsewhere to store reserve ammunition. Each gun has their own O2 and H2 generation and storage facilities. All eight guns would be located together in a circle. All guns would be centralized around a single fire control center able to fire them together or independently. The guns themselves have less capable redundant fire control systems, along with manual range tables as well.

Ammunition for the gun was developed by teams who had previous experience with designed armor-piercing ammunition for battleship guns. When the shell design was finalized with the M803, design work for the regular use shell was begun. Along with the regular use round, named High-Explosive Asteroid-Penetrating in an attempt to detract attention from the military use of the HALOS, two atomic weapons were developed in strict secrecy. A 1.2 megaton shell and a 170 kiloton shell were developed for air and ground targets in a military capacity, namely against massed air targets or to intercept ICBMs and their MRVs. Shells were stored outside of the facility at a nuclear weapon storage facility and guarded by separate military police units.

Crew are located on the gun and in a hardened bunker complex in front of the gun mount. Crew on the gun oversee operation, condition, and loading of the gun, while the crew in the bunker handle fire-control coordination with the centralized fire control center or the CFCC.

The entire system is shock-hardened and designed to be resistant to an EMP attack.

Construction

Construction in 1986

Construction of the base began in 1982. The location was the Sandy Air Force Base in the Great Sandy Desert. Sandy AFB historically had been a test a research base for desert equipment of the armed forces, and the Great Sandy Desert itself was a centrally located point on the contientient. As well while being a desert the average temperature is much lower than other comparable deserts due to the elevation. As well, while in the larger Great Sandy Desert, the area the base is located in is known as Caldwell Desert, a notably rockier and stable location. This allowed for stable foundations to be built without risk of sinking in desert sand.

The guns had begun production at a number of armories and foundries. Parts would need to be produced partially completed and then transported to the base site for final assembly. Rail lines were rapidly built by army engineers, and parts would be moved in by rail, road, and by air when needed.

Some 25,000 construction workers would be contracted during the duration of construction along with thousands of engineers from dozens of design firms, engineering organizations, and also scientific groups. Infrastructure to operate the guns were prioritized, with the guns then worked on after that. Much of the underground rail network, ammunition storage, and crew facilities were finished by 1985, with work moving to the guns in the year after. Guns Number 1 ‘Thomas Stone’ and Number 2 ‘Spencer Delaney’, were finished by the middle of the year. The naming convention of the guns would be after presidents of Hyboria and of the preceding Republic of Jothain.

Test firing of the guns was conducted shortly after completion, and a test interception of a projected fragment impact was also done. Gun No. 2 ‘Spencer Delaney’ intercepted a 100 m fragment on August 11, 1986, making the first purposefully, successful interception by any ground-based system in the world.

Later that year, most of the third and fourth guns were done, and were conducting crew training and familiarization. Entry into the Omandan Continental War in 1987 greatly sped up construction of the entire base, and was not paused even during the use of the guns, tho construction workers were informed beforehand and would seek shelter to protect themselves from the concussive force of the guns firing.

Ammunition

• Projectile, 48-inch: Test, M800: Initial test projectile used in the mid-1980s. M800, M801, M802 and M803 were all test projectiles used to prove the design
• Projectile, 48-inch: Test, M801
• Projectile, 48-inch: Test, M802
• Projectile, 48-inch: Test, M803
• Projectile, 48-inch: Dummy, M804: Training munition used in cycling the reloading system, based on final design of the M803
• Projectile, 48-inch: High-Explosive Asteroid-Penetrating, M805 (HEAP): First model shell used to engage asteroid fragments, used to a limited role against massive aircraft formations. Improved into the M805A1 model. Replaced by the M807 I-HEAP round. Used in over 129 interceptions of asteroid fragments.
• Projectile, 48-inch: Artillery Fired Atomic Projectile, M856 (AFAP): First type of nuclear munition developed, used the W56 warhead with a 1.2 megaton yield. Was considered for use in both anti-air, BMD, and also in the anti-ground role. Was never used, less than 20 produced and all decommissioned by 2010. Designation of M856 was given as it used the W56 warhead.
• Projectile, 48-inch: Artillery Fired Atomic Projectile, Anti-Aircraft, M862 (AFAPAA): Used the W62 thermonuclear warhead with a yield of 170 kilotons. Used multiple times during the OCW. Total number produced is classified, possibly over 400 rounds. Production is ongoing with the improved M862A1, taking advantage of improvements applied to M807.
• Projectile, 48-inch: Atmospheric Testing, M806 (AT): Used for atmospheric testing experiments.
• Projectile, 48-inch: Improved High-Explosive Armor-Piercing, M807 (I-HEAP): Improved model of shell produced by the end of the OCW, did not see service during. Current in-production shell.
• Projectile, 48-inch: High-Explosive Armor-Piercing, Rocket-Assisted, M808 (HEAPRA): New shell in development or already in service, range is reported to be "greatly extended".