All Terrain Armored Transport/Legends

"We had the Battle of Gormen won, until the AT-ATs arrived. They came out of the fog and ripped apart the front lines. The locals ran in terror, but the experienced soldiers surrendered. We knew that you can't outrun an AT-AT."

- Major Bren Derlin, Rebel Alliance field commander

The All Terrain Armored Transport (AT-AT) walker was a major part of the Galactic Empire's army. It was one of the most heavily armored land vehicles in the Imperial Army, but was also known for its relatively slow speed.

Characteristics
"Lookit 'em, boss! Great, big, fat gray targets!" "I know, Zev, but they've got a long reach."

- Zev Senesca and Luke Skywalker, during the Battle of Hoth

The AT-AT walker was a behemoth of a war machine, standing at a height of 22.5 meters. The quadrupedal walker closely resembled ancient beasts of war, or even a giant legendary beast from the dark side of the Force. Designed for the dual purpose of crushing and demoralizing enemy forces, and also serving as a transport for Imperial troops and light vehicles, the AT-AT was unsurpassed as the most awesome vehicle in the Imperial Army inventory. Its intimidating and powerful presence often earned it the distinction of being the first vehicle into a combat zone.

Serving as the "head" of the mechanical walker was a movable command section containing the command cockpit, with room for the commander, pilot, and gunner. The command section housed all of the AT-AT's weapon systems, as well as holographic targeting systems allowing the gunners a 360-degree view of their position. The cockpit was also equipped with a holographic projector for purposes of external communication. Forward visualization was supplied by a glowing red command viewport. The head could rotate as much as ninety degrees right or left and thirty degrees up or down for an expansive field of fire. Positioned above and below the command section was the walker's sensor array and blaster cannon energizer, respectively.



The command head was attached to the trapezoidal armed body section by a flexible armored tunnel, allowing cockpit access from the rest of the machine. The AT-AT's troop section could typically carry five speeder bikes, up to forty troops normally comprised of Imperial stormtroopers or Imperial land assault troopers in a double-tiered passenger section, and heavy weaponry, such as E-web heavy repeating blasters. The AT-AT could also variably hold two All Terrain Scout Transports in lieu of soldiers in a rear vehicle bay, though they required partial disassembly to fit inside. Housing the troop section were two large side panels; each one held an escape hatch. The rear panel also housed the troop staging area. Positioned in the center of the body section was a rectangular boarding hatch with sliding ramps where the AT-AT's complement of troops loaded and disembarked. An AT-AT unloaded its troops by kneeling to three meters above ground level until the boarding ramp could extend outward. Individual stormtroopers could also be deployed rapidly by rappelling cable.

Below the troop body section were two immense Kuat Drive Yards FW62 compact fusion drive systems that, in conjunction with the walker's four giant heavily-reinforced legs, propelled the AT-AT forward at a top speed of sixty kilometers per hour. However, this maximum rate was achievable only on a flat, stable terrain. At the rear of the drive motors were the walker's three fuel slug tanks, connected to the drive motors, that powered the massive machine. The AT-AT's rear also included atmospheric exchangers and a filtration unit to regulate the interior living conditions. The walker's legs were supported by massive durasteel footpads with impulse terrain sensors, supplemented each by toe flaps, that could crush obstacles in its path with little effort, effectively helping the AT-AT to live up to its name. The legs did, however, require constant maintenance and repair. As the titanic walker marched down the battlefield, its heavy, stomping feet would cause the ground to shake, demoralizing the enemy before they were even engaged.

The AT-AT's formidable offensive capabilities were supplied by dual, chin-mounted Taim & Bak MS-1 fire-linked heavy laser cannons for slower, more cumbersome targets and two fire-linked medium repeating blasters mounted on each side of the head designed for lighter, agile targets. The two sets of weapons could be independently rotated in order to engage multiple targets at once. However, the AT-AT head, which could move between a range of left, center, and right firing arcs, could only rotate one fire arc per heavy laser volley. The walker's strong external durasteel armor was virtually impervious to all but the heaviest of artillery weapons.

The most vulnerable part of the walker was a weak point found at its flexible neck, which was susceptible to lighter blaster barrages. The legs were also somewhat unstable and could be tripped, leaving the walker defenseless. While first appearing to be a slow, lumbering vehicle, the AT-AT would often times be on top of its enemies before they knew what had hit them. The AT-AT also lacked armor covering on its underbelly, leaving the spot vulnerable to mounted guns or portable missile launchers. To remedy this weakness, AT-STs were usually stationed around the flank of the walker to ensure nothing was given a clear shot at the AT-AT's weak underside.

AT-ATs were typically deployed for ground assault from orbit by large dropships. Walkers stationed within larger warships, such as the Executor-class Star Dreadnought, were delivered to planetary surfaces within Incom Y-85 Titan dropships, capable of carrying four 22.5-meter AT-ATs. Smaller ships, such as the Imperial-class Star Destroyer, deployed single walkers via the Theta-class AT-AT barge. Other designs, including the Telgorn Corporation Warlord Dropship, were capable of delivering a platoon of four walkers.

Modified variants
The Empire utilized several modified variants of the standard AT-AT design for purposes of fitting certain mission profiles in specific environments. The walkers used at the Battle of Hoth in 3 ABY&mdash;nicknamed "snow walkers"&mdash;were specially designed with heat circulation systems, de-icing controls, and energy efficient environmental controls. The AT-AT "dune walker" was a desert terrain walker fitted with Sienar Fleet Systems z23 heat dissipation units; while the Aquatic Terrain Armored Transport, known as the AT-AT "swimmer," was a repulsorcraft cousin of the standard model.

Origin and development
In the wake of drawbacks realized in the design of repulsorlift vehicles&mdash;drive system failures spawned by gravity fluctuations and unusual planetary magnetic fields, among others&mdash;the Galactic Empire saw the need for a capable heavy assault vehicle that could effectively function on any terrain on any given number of worlds. Thus, designers turned to ancient technology that had received limited use in vehicles such as the Galactic Republic's All Terrain Personal Transport, but that had not been applied on such a grandiose scale.

The finished AT-AT product, while at first derided by many Imperial officers, nonetheless surpassed the Empire's expectations. The walker embodied the Imperial philosophy of fear over function; indeed, the AT-AT's massive size alone proved to be a potent psychological weapon. It served as a weapon of terror on a level equivalent to that of its combat efficiency.

Clone Wars


AT-ATs were assembled by Kuat Drive Yards, and evolved from the AT-TE walkers first employed in the Battle of Geonosis. The first-generation AT-AT walkers saw their debut during the Battle of Jabiim, later on in the Clone Wars. During this battle, the overwhelmed Confederacy forces were annihilated in the beginning.

Some seemingly managed to fall into the hands of the Confederacy of Independent Systems, through unknown means. These were stationed on the Separatist world of Diado.

Galactic Civil War
During the time of the Galactic Empire, Maximilian Veers resurrected the idea, bringing the AT-AT into full Imperial service, even in early campaigns like the one at Kashyyyk. The AT-AT was deployed on a wide array of worlds in the months following the Battle of Yavin, including Corellia, Chandrila, and Gormen. Nearly three years after the Battle of Yavin, Veers neared completion on a superior model of the walker on Zaloriis, nicknamed "Dune Cow". With the prototype Blizzard I, which was constructed in Camp Culroon, he assaulted the planet's capital when they declared affiliation with the Rebellion.



At the Battle of Hoth, the Empire used the Blizzard Force walkers to land beyond the limits of the Rebel Alliance's shield, although a few were lost to the treacherous terrain before the battle even began. General Maximilian Veers commanded the ground forces and advanced on the shield generator, decimating Rebel troopers in their trenches.

Faced with such forces, Luke Skywalker employed a strategy earlier devised by himself and strategist Beryl Chiffonage to disable the walkers: his team of snowspeeders would use their magnetic harpoons and tow cables to entangle the walkers' feet, causing them to fall. Wedge Antilles and his gunner Wes Janson managed to disable one walker this way. Luke destroyed a second by cutting a hole in it with his lightsaber and tossing in a concussion grenade, and a third was destroyed when a speeder crashed into it. Dash Rendar was able to bring down a fourth through unknown means.

Despite these small successes, they were ultimately insufficient to turn the tide of the battle, and the Battle of Hoth was one of the most devastating losses for the Rebels in the entire Galactic Civil War. The AT-ATs succeeded in destroying the shield generator, thereby allowing the main Imperial force to land and attack Echo Base. The AT-ATs would go on to devastate the Rebel defenses.



The walkers later patrolled the garrison base on the forest moon of Endor, but were limited in their range by the dense foliage of the moon; as a result, smaller vehicles such as AT-STs saw far more use.

Sometime after the Battle of Endor, the Empire replaced the AT-AT's lasers and blasters with light turbolasers, easily capable of defeating many highly protected defensive weapons emplacements.

By 9 ABY, Nomad City on Nkllon was a mining operation owned by Lando Calrissian. The city was built from a Dreadnought-class heavy cruiser mounted on top of 40 captured AT-ATs to move the city constantly away from the day side of Nkllon and prevent it from being destroyed by intense radiation of Nkllon's daytime. However, the city was damaged and then abandoned, and Nomad City and its AT-ATs were destroyed by the intense radiation.

During the reborn Emperor Palpatine's insurgency in a clone body from 10 ABY to 11 ABY, the Empire developed a new variant of the AT-AT that was equipped with the most powerful Imperial turbolasers and the new X-80 power cells. These were deployed during an attack on New Alderaan. During the battle, they vaporized many buildings, gun emplacements, and starfighters.

Following the Galactic Civil War, AT-ATs were also used by the New Republic, the Galactic Federation of Free Alliances, and various other governments. During the Yuuzhan Vong War, the Myrkr strike team found one of these vehicles on the Yuuzhan Vong Koros-strohna Baanu Raas in 27 ABY. AT-ATs were also deployed by the Galactic Federation of Free Alliances during the liberation of Coruscant in 30 ABY.

Behind the scenes
The name "AT-AT" is never spoken in any of the films. Instead, the machines are referred to as "Imperial walkers."

The AT-ATs used in The Empire Strikes Back and the brief appearance in Return of the Jedi were created with the use of stop-motion animation.



Star Wars: Galactic Battlegrounds has a mission which describes the creation of the AT-ATs and their introduction to the service of the Empire. All this happens before the Battle of Hoth. However, there are several appearances of the AT-ATs in BBY sources, including the games Star Wars: Rebel Assault and Star Wars: X-wing. The first is S-canon; however, the latter is accepted as C-canon and shows them in the Battle of Orion IV. First-generation AT-AT walkers are featured in the story-arc Star Wars Republic: The Battle of Jabiim. Star Wars: Empire at War shows them being introduced before the Battle of Yavin.

AT-AT is pronounced "at-at" in Star Wars: Force Commander, and Star Wars: Galactic Battlegrounds. They are also called "A-T-A-T"s briefly in Star Wars: Rogue Squadron II: Rogue Leader. In Star Wars Battlefront 2 both terms are used.

When there was a wrong leg animation with the AT-ATs, George Lucas would take that scene and make a turret shoot it in the leg. This supposedly happened twice.

George Lucas says he got the idea from the massive tripods from H.G. Well's 1898 novel The War of the Worlds.

The animators who brought the AT-AT Imperial Walkers to life in Episode V: The Empire Strikes Back based their movements on elephants.

Height discrepancies
"Outpost Beta here. I have a visual now. These things look like &hellip; animals. They're huge, maybe twenty, twenty-five meters high, four-legged, and their heads move. But they're made out of metal. They have extremely heavy armor and armament. I count six of 'em so far."

- BETA, in the script of the The Empire Strikes Back radio dramatization

"Outpost Beta here. I have a visual now. These things look like &hellip; animals. They're huge, maybe ten, fifteen meters high, four-legged, and their heads move. They're made out of metal. They have extremely heavy armor and armament. I count six of 'em so far."

- BETA, in the recording of The Empire Strikes Back radio dramatization

In "Forces of the Empire," an article that was first published Issue 2 of The Empire Strikes Back Official Poster Monthly, the All Terrain Armored Transport was described as "a fifty-foot tall armored exoskeleton." The figure of fifty feet was likely derived from sources such as The Empire Strikes Back Sketchbook, which suggested that the designers of the model intended for the AT-AT to appear to be fifty feet tall on screen. In 1987, this figure was given as the height for the AT-AT in the first edition of a A Guide to the Star Wars Universe

In 1983, The Empire Strikes Back radio dramatization included a scene in which a young Rebel officer, who would be later identified as Trey Callum, gave the command staff of Echo Base a rough estimate of the height of the AT-ATs approaching his location. His statement that they were "twenty, twenty-five meters high" in the script later was changed to "ten, fifteen meters high" in the recorded version.

Supplements for West End Games's Star Wars roleplaying game listed the All-Terrain Armored Transport at a height of 15.5 meters. Inside the Worlds of the Star Wars Trilogy revised the AT-AT's height to 22.5 meters in a section dealing with the dropships that were used to land the walkers during the Battle of Hoth. This larger figure was based upon unofficial calculations by Curtis Saxton, with whom James Luceno, the author of the book, consulted on technical matters. This figure was repeated by Star Wars: Complete Locations, a compilation of the Inside the Worlds of Star Wars series, but the "Episodes IV-VI Data Files" section of Star Wars: Complete Cross-Sections listed the AT-AT's height at 15.5 meters, adding further confusion to this issue.

Non-canon appearances

 * LEGO Star Wars II: The Original Trilogy
 * LEGO Star Wars: The Complete Saga
 * Star Wars Infinities: A New Hope
 * Star Wars: Rebellion
 * Star Wars Infinities: The Empire Strikes Back
 * Moment of Doubt