Like the preceding Delta-class DX-9 transport, the ATR-6 had two general purpose warhead launchers, and a pair of forward-firing ion cannons. Both were designed to ferry troops into the combat zone to capture enemy craft.
Unlike the Delta-class DX-9 transport, the ATR-6 has no frontal laser cannons. However, it more than made up for it with its four turrets, on the top, bottom, and both sides, which covered all arcs. This allowed the ATR-6 to fire upon its target without having to fly directly at it, giving it more opportunity to inflict damage. It also crucially enabled the ATR-6 to fend off all but the most concentrated starfighter attacks on its own. Its turrets, coupled with heavier shielding, and armor, allowed the ship to press attacks in the face of heavy fire, relying less upon supporting starfighters to soften up well defended targets.
The ATR-6 also featured stronger shields and a more heavily reinforced hull than the DX-9. While the DX-9 could be destroyed with a pair of proton torpedoes, it was reported that an ATR-6 could survive three hits from such warheads.
A further development of the ATR-6 was the Beta-class ETR-3 escort transport. The ETR-3 retains the ATR-6's base hull, giving it approximately the same size same troop-carrying capacity. However, the ETR-3 has an additional dorsal pod, reintroduces frontal laser cannons, and has stronger shields and reinforced armor. The ATR-6, however, remained the mainstay of the forces already using it.
The ATR-6 was a deadly threat to any attacker, especially if it was an unshielded craft. During the Sepan Civil War, the Ripoblus conducted an attack on the Dimok Science Station Youst spearheaded by six Assault Transports. The station's defending fighters, consisting of Z-95 Headhunters and Delta-class JV-7 escort shuttles, quickly fell victim to the turrets of the ATR-6 that they were trying to attack.
When Admiral Harkov's forces entered the area to repel the Ripoblus, they deployed TIE/sa bombers to take out the ATR-6s from a safe distance with proton torpedoes. Imperial pilots discovered that a full-strength ATR-6 could survive even three torpedo hits, with several Bombers lost trying to finish off the injured ATR-6 with laser cannon fire. Maarek Stele opted wisely to replace his payload with proton rockets, which required more careful aiming, but one of these devastating warheads was enough to quickly destroy an ATR-6.
In groups, the ATR-6 could take on vessels sufficiently larger than itself, especially if the proton torpedoes were replaced with the more devastating heavy rockets. One example of this was the traitor Admiral Demetrius Zaarin's unsuccessful recapture operation of the TIE/D Defender research facility in the Parmel system. His attacking force of Assault Transports fended off TIEs from the Imperial-class Star Destroyer Adarga and went on to inflict significant damage on the loyalist capital ship itself. Having forced Agarda to flee into hyperspace, Zaarin's transports came close to capturing the R&D facility, before being thwarted by loyalist Maarek Stele.
Stele employed some innovative tactics against the overwhelming force of ATR-6s, intercepting as many of their rockets before they could hit Adarga, and using ion cannons to disable any damaged ATR-6. In a twist of irony, loyalist Imperial forces led by Stele had earlier used the same class of ATR-6s, though fewer, to seize the TIE Defender base.
In Star Wars: TIE Fighter and X-wing Alliance the ATR-6 was described as product of KonGar Ship Works. However, X-wing vs. TIE Fighter listed Telgorn Corporation as its manufacturer. This discrepancy has yet to be explained, though it is possible that the companies collaborated on the design or that KonGar is a subsidiary of Telgorn. The follow-up ETR-3 was produced by Telgorn.
The Gamma-class ATR-6 assault transport appeared in the X-wing series of computer games. A similar but distinct ship, Gamma-class assault shuttles, were first described in the West End Games publication Imperial Sourcebook. At first, it was unclear whether the assault transport was intended to be the same thing as the assault shuttle, because the games were known to use alternate models and statistics for a number of ships. However, both the assault shuttle and assault transport appeared in Star Wars: X-Wing Alliance, proving that they were separate ships. Unlike the Gamma shuttle, the ATR-6 assault transport has not been seen in many sources outside the X-wing games.
The Gamma-class ATR-6 assault transport and Delta-class DX-9 transport were briefly mentioned in The Essential Guide to Weapons and Technology as carrying a pair of proton torpedo launchers.
- TIE Fighter: The Official Strategy Guide
- TIE Fighter: Defender of the Empire: Official Secrets & Solutions
- TIE Fighter Collector's CD-ROM: The Official Strategy Guide
- The Essential Guide to Weapons and Technology
- Star Wars: X-Wing Alliance: Prima's Official Strategy Guide
- The Official Star Wars Fact File129