An Interdictor Cruiser is a starship from the fictional Star Wars Expanded universe capable of interfering with hyperspace travel with gravity wells. They are most common to the Imperial Starfleet, but can be found serving with other forces. Strictly speaking, Interdictor Cruiser refers to the Immobiliser-class but this article also mentions other vessels that share the same unique capability.
The Immobiliser-418 -class Interdictor Cruiser is a starship from the fictional Star Wars universe. Built upon the Vindicator-class Heavy Cruiser, it is a special-purpose vessel, the first warship class of the Imperial Starfleet to incorporate gravity well generators as standard equipment. These generators, when engaged, simulate the presence of a medium-sized planetary body and in particular the effect such a body would have on hyperspace travel. This can be used for two purposes, to prevent vessels entering hyperspace, and to force craft currently in hyperspace to revert to sublight speeds.
Interdictor cruisers were initially developed as a counter to the Rebel Alliance’s hyperdrive-equipped starfighters in particular, and hyperdrive equipped vessels in general. This was primarily to counter Alliance "hit and hype" tactics, where a small group of starfighters or light starships would emerge from hyperspace, attack preselected targets, and re-enter hyperspace before sufficient force could be brought to bear on the raiders.
An Interdictor at the site of attack, or able to access the area with a brief hyperspace jump, would be tasked to power up its gravity well generators in an attempt to prevent the escape of the raiding party. Starfighter and capital ship support were then be used to eliminate the attackers, whose only options were to try to run for the edge of the interdiction field, or to attack the Interdictor and hope to inflict enough damage to disable the cruiser’s influence. Either path would result in significant damage to the Alliance forces. Rebel pilots often mistook it for a miniature Star Destroyer when it was accompanied by Star Destroyers. It was only when they tried to escape into hyperspace that they realized it was an Interdictor.
A secondary duty of this class was to patrol trade routes. Freighters pulled out of hyperspace by an Interdictor would be in a position to have their cargo inspected.
The Immobiliser class had several weaknesses. Foremost was that the gravity well generators took several minutes to "warm up" (though the duration was rarely enough for an entire fleet to escape), and were an extremely large drain on the ship’s resources. This flaw was used on several occasions. When enemy ships were able to inflict significant damage to the Interdictor, the captain was forced to choose between entrapment of the enemy and his ship’s own protection. Interdictors were also poorly protected and armed for their size, unable to successfully match up with vessels of equal size. In fleet operations, they were usually found on the periphery of the battle they were affecting, dependant on better equipped capital ships and starfighters to deliver the necessary damage.
During the Galactic Civil War, only a few hundred Interdictors were built, as they were more expensive than a regular Star Destroyer of comparable size, were less effective in battle, and their primary use was strategic.
Following the Battle of Endor, Imperial warlords, such as Grand Admiral Thrawn, realized the importance of the ship and carefully deployed them. Thrawn was especially famous in connection with Interdictors for developing and refining a tactic that would be named after him. The "Thrawn pincer" positioned the Interdictor's gravity wells along certain vectors. Other vessels (typically Star Destroyers) would be contacted, and would blindly execute a micro-hyperspace jump straight into the Interdictor's gravity wells, yanking them out of hyperspace and near an enemy vessel. Much quicker that subspace movements, the Thrawn pincer allowed reinforcements to be swiftly deployed on the battlefield and afforded a considerable element of surprise.
Several months after the Battle of Endor, a new interdictor class became prevalent. Known as the Dominator class (after the first ship of its kind to make an appearance), it appeared to be built off the same hull structure as Imperial-class Star Destroyers. Because of these similarities, it was likely produced by Kuat Drive Yards in order to rival Sienar Fleet Systems.
The new class was designed to counteract one of the Immobiliser-class' main weaknesses, the ability to hold its own in combat. Armed with similar weaponry to Imperial-class Star Destroyers, and carrying four squadrons of TIE fighters, a Dominator did not require additional support when performing patrol and customs duties. Some bold commanders even used the ship to pull armed convoys out of hyperspace and destroy them. Nonetheless, like the Immobiliser, the gravity wells remained a major drain on the ship's main reactor. This had the potential to compromise the Dominator's defences in heavy combat.
The behemoth Eclipse-class Star Destroyer (and the smaller Sovereign-class relative) incorporated gravity wells into its design. Its sheer size and weaponry (which rivaled the Death Star) already made it almost unstoppable by practical means. However, the ability to prevent escape into hyperspace gave the enemy no choice but to either surrender or be pressed into an engagement that the Eclipse was certain to win.
Interdictor cruiser development appears to have stagnated after this point, the next innovation not coming until during the Yuuzhan Vong invasion. At least three Defender-class Star Destroyers were modified to house completely internal gravity well generators.
Known examples of Interdictor Cruisers
- Galactic Empire
- Aggregator – Owned by High Admiral Teradoc. Loaned to Ysanne Isard during her rule on Thyferra. Driven off by Rogue Squadron.
- Black Asp
- Stellar Web – Assigned to the taskforce hunting Warlord Zsinj.
- Rebel Alliance/New Republic
- Corusca Rainbow (formerly Black Asp) – Defected to the Alliance only a few months prior to the invasion of Coruscant.
- Harpax - Part of Darth Vader's taskforce hunting for the remaining forces of the defecting Admiral Harkov in the Parmel System, it was destroyed when Imperial loyalists came under surprise attack from rogue Admiral Zaarin.
- Grappler - used by the traitor Admiral Zaarin to trap loyalist Admiral Thrawn after the latter had captured Rebel magnetic pulse (mag pulse warheads) technology in the Omar System. During the battle, the Grappler was temporarily incapacitated by a mag pulse warhead fired by Maarek Stele, enabling Thrawn's flagship VSD Scheltor to escape.
- Red Claw - used by Imperials in the Eva-T System to trap pirates attempting to sell the TIE Defender scientist to the highest bidder. However, its hyperdrive was knocked out by a surprise attack from another group of pirates, although both groups were captured. While awaiting repair, Red Claw was later destroyed by Admiral Zaarin's forces who also made off with the scientist; it was later found out that the Red Claw's captain had collaborated with Zaarin in allowing this to occur.
- Galactic Empire
- Dominator - Encountered by the Rebel Alliance at Mrlsst. Captained by a space pirate-turned-Imperial officer who murdered Wedge Antilles' parents.
- Binder - Part of Admiral Krennel's force at Ciurtic.
- Constrainer, Sentinel – Part of Grand Admiral Thrawn’s forces. Responsible for trapping the New Republic fleet at Bilbringi.
The listing is controversial since Binder, Contrainer, and Sentinel were called Interdictors (and presumed to be Immobiliser) in the novels, although they were drawn as Dominators in the Dark Horse comic series. Also, Dominator is not the official class name but the community named it such after the first ship of its kind to make its appearance.
Eclipse-class Super Star Destroyer
Sovereign-class Super Star Destroyer
- Galactic Alliance
- Mon Mothma, Elegos A'Kla, Bail Organa - Developed during the second half of the Yuuzhan Vong invasion.