The Deimos Whirlwind, officially the Deimos Pattern Whirlwind Multiple Missile Launcher Tank, also known as the Deimos Pattern Whirlwind, is a variant pattern of the Whirlwind artillery vehicle that is used by the Adeptus Astartes. The Deimos Whirlwind differs from the more common Mars Pattern Whirlwind in that it is based upon the Standard Template Construct (STC) Deimos Rhino Armoured Personnel Carrier (APC) chassis.
The Deimos Whirlwind plays the role of artillery support, providing support fire against enemy formations from the relative safety of geographical cover, such as behind hills, forests or other line-of-sight obstructions. It is intended to be used primarily for softening up a heavily-fortified static position or other well-defended target prior to the start of a major Space Marine assault. The Deimos Whirlwind, like most vehicles based on the Deimos Rhino Pattern chassis that was commonly used during the Great Crusade, is considered a relic amongst the present day Space Marine forces. Like any vehicle from that long-lost era, the Deimos Whirlwind is only deployed in the most dire of circumstances.
The Deimos Pattern Whirlwind was first used by the Legiones Astartes during the Great Crusade in the late 30th Millennium, where the term "Whirlwind" was used to describe a range of vehicle-mounted multiple missile launcher systems, many of which had just been recovered during the Great Crusade's march across the galaxy. Many of these launcher systems, such as the Scorpius Multi-Launcher, were still undergoing front-line trials with various units before the fires of the Horus Heresy swept across the Imperium. The Deimos Whirlwind was deployed in large numbers alongside other artillery units used by the Space Marine Legions, most notably the Legion Medusa and Legion Basilisk. The Whirlwind has the advantage over these heavier vehicles of being built upon the lighter and more mobile Deimos Rhino chassis. This also made the vehicle easier to repair and support. After the outbreak of the Horus Heresy and the Great Scouring, the Deimos Whirlwind, along with the Mars Pattern Whirlwind, would eventually become the main mobile artillery units employed by the newly-founded Space Marine Chapters.
The Deimos Whirlwind is equipped with a dorsal-mounted Whirlwind Multiple Missile Launcher that is placed on a rotating turret atop the vehicle that is capable of firing a number of different types of missile ordinance. The Whirlwind, like all other Deimos Rhino variants, can also be outfitted with Dozer Blades, Extra Armour Plating, a Hunter-Killer Missile Launcher, improved communications equipment, a Pintle-mounted Storm Bolter, a Searchlight, and Smoke Launchers. During the Great Crusade and Horus Heresy in the late 30th and early 31st Millennia, the Deimos Whirlwind was capable of being outfitted with weapons and technologies no longer known or used by the Imperium in the late 41st Millennium, such as twin-linked Bolters, Pintle-mounted twin-linked Bolters, and an auxiliary drive system. The Whirlwind was also able to replace its standard missiles for Hyperios Air-Defence Missiles in order to engage enemy aircraft. During these ancient times a Whirlwind could also be used as a command vehicle for Legion artillery formations.
The Whirlwind Missile Launcher is capable of firing multiple types of missiles, including:
- Vengeance Missiles - Vengeance Missiles represent the standard high-explosive missile warhead used by the Astartes.
- Castellan Missiles - Castellan Missiles are tipped with a special warhead that can be set to explode at specific times and altitudes to scatter small, mine-like bomblets across a designated target area. Castellan Missiles can establish makeshift mine fields quickly and without exposing Imperial forces to unnecessary dangers while laying mines.
- Incendiary Castellan Missiles - An Incendiary Castellan Missile's warhead had been further modified to scatter burning Promethium over a designated target area rather than bomblets. These horrific weapons are used to burn lightly-armoured enemy infantry and light vehicle formations to death.
- Hyperios Air-Defence Missiles - The Deimos Whirlwind is capable of firing Hyperios Anti-Air Missiles that are guided to strike enemy aircraft. The Deimos Whirlwind Hyperios uses similar missiles, although the anti-air weapons used by the Deimos Whirlwind Hyperios are much more effective at the anti-aircraft role. Whirlwinds armed with Hyperios Anti-Air Missiles are rarely deployed on the battlefield, due to the existence of the aforementioned more effective alternatives.
The following are all known Deimos Whirlwind variants:
- Deimos Whirlwind Hyperios - Much like the more common Mars Pattern Whirlwind, the Deimos Whirlwind can be armed with the Hyperios Multiple Missile Launcher. This is perhaps the rarest of the Whirlwind variants, as it requires an ancient Deimos Whirlwind to be armed with a more modern, and untrusted, weapon system.
- Deimos Whirlwind Scorpius - The Deimos Whirlwind Scorpius is a rare variant of the ancient Deimos Pattern Whirlwind that was widely used by the Space Marine Legions during the Emperor's Great Crusade and the Horus Heresy in the late 30th and early 31st Millennia. The Deimos Whirlwind Scorpius mounts a specialised anti-infantry rocket launcher, known as the Scorpius Multi-Launcher, in place of the vehicle's original Whirlwind Multiple Missile Launcher.
A standard Deimos Whirlwind is armed and equipped with:
The Deimos Whirlwind's Whirlwind Multiple Missile Launcher may also have a variety of warheads such as:
- Vengeance Missiles (Standard Loadout, High-Explosive)
- Castellan Missiles (Standard Loadout, Cluster-type Explosives)
- Hyperios Air-Defence Missiles (Optional, Anti-Air Missiles)
The Deimos Whirlwind can be armed with the following pintle-mounted weaponry:
Any Deimos Whirlwind could be outfitted with the following vehicle equipment:
When in a squadron of three, one Legion Artillery Tank can be upgraded to the following:
- Squadron Command Tank
Adeptus Mechanicus Technical Specifications
The technical specifications of this vehicle have not been publicly released by the Adeptus Mechanicus.
- The Horus Heresy: Book One - Betrayal (Forge World Series) by Alan Bligh, pg. 220
- The Horus Heresy: Legiones Astartes - Crusade Army List, pg. 80
- The Horus Heresy: Legiones Astartes - Age of Darkness Army List, pp. 68, 80
- The Horus Heresy: Collected Visions (Artbook), pp. 161, 342
- The Horus Heresy: Visions of Heresy (Artbook), pg. 199