Interdictor

A warship type referred to as an Interdictor, or Interdictor vessel, could prevent starships from entering hyperspace or forcibly remove them into realspace. This was achieved via gravity well projectors that generated artificial mass shadows. These gravity well projectors were typically spherical. Many Interdictor models were equipped with a total of four projectors. Interdictors also existed across different starship classifications, such as Star Destroyer, heavy cruiser, cruiser, and frigate.

During the Imperial Era, one of the initial Interdictor models was the Detainer CC-2200 cruiser. It featured short, wing-like lateral projections that housed the four gravity well projectors. The design also incorporated thick armor, a sloping bow, and sublight engines. The CC-7700 frigate shared these design elements but represented an updated version of the earlier CC-2200. The Immobilizer 418 cruiser measured 600 meters in length and included four spherical gravity well projectors integrated into its hull. It also carried twenty-four TIE fighter series craft and was armed with twenty laser cannons. Despite its cutting-edge design, the Immobilizer suffered from numerous technical problems upon its introduction.

The Interdictor-class heavy cruiser represented an advancement of the Immobilizer, featuring a delta wing-shaped design with four spherical gravity well projectors on its hull. These projectors were a weak point; their destruction could jeopardize the entire ship. Eventually, both the Immobilizer and the Interdictor-class cruiser were discontinued and replaced by the Interdictor-class Star Destroyer. This vessel, derived from the standard Imperial-class Star Destroyer, measured 1,600 meters in length and offered improved protection.

Interdictor vessels were used to create interdiction fields, either to force enemy ships out of hyperspace or prevent them from entering it. With these capabilities, Interdictors could blockade planets, investigate potentially dangerous hyperspace routes, and participate in small battle groups or task forces, providing support to larger capital ships in conjunction with frigates and starfighters. Interdictors were stationed at strategic points along patrol routes to intercept ships exiting hyperspace for inspection. While Interdictors could operate with an escort, they were also capable of independent operation in emergencies.

The technology for gravity well projectors demanded a substantial, stationary power source for hundreds of years. This limitation prevented the development of Interdictor vessels. During this time, gravity well technology was primarily used to safeguard critical installations by preventing travel nearby. However, this changed due to research conducted during the Clone Wars, resulting in more efficient projectors and Imperial field tests involving gravity well projectors mounted on a space-faring vessel. Following the Clone Wars and into the Imperial Era, the Imperial Navy employed Interdictor vessels to manage hyperspace traffic, although the technology remained constrained. In 14 BBY, during the Berch Teller campaign, Imperial Vice Admiral Dodd Rancit suggested using Interdictors to retrieve the Carrion Spike, the hijacked personal vessel of Moff Wilhuff Tarkin. The task force deployed three Interdictor vessels: an older Detainer CC-2200 cruiser, a newer CC-7700 frigate, and a newly developed and untested Immobilizer 418 cruiser, designed for the Deep Core Security Zone.

The task force activated its Interdictor vessels in an attempt to capture the Carrion Spike corvette within the Obroa-skai system. However, the Interdictors failed, causing an incident where multiple civilian ships were pulled from hyperspace, resulting in civilian deaths. The Immobilizer was returned to the Corellian Engineering Corporation for repairs to address its operational issues.

By 4 BBY, a prototype Interdictor-class heavy cruiser, named the Interdictor, was undergoing evaluation in the Del Zennis system under the command of Admiral Brom Titus. The Interdictor-class cruiser was an evolution of the Immobilizer 418 cruiser, and part of the Interdictor line which included combat, suppression, and experimental refits. The Interdictor operated alongside two other Interdictor cruisers, pulling a CR90 corvette out of hyperspace. The Interdictor eventually captured the rebel corvette Liberator and its crew, including Commander Jun Sato and Ezra Bridger. During a rescue attempt by other Phoenix Cell members, the Interdictor and its escorting Arquitens-class command cruisers were destroyed.

During the Lothal campaign's culmination with the Battle of Atollon in 2 BBY, Grand Admiral Thrawn deployed two Interdictor-class cruisers along six Imperial-class Star Destroyers of the 7th Fleet to capture Rebel Alliance leadership and destroy Phoenix Cell and Massassi Group. One Interdictor was under the command of Admiral Kassius Konstantine, but it was destroyed when Commander Sato sacrificed himself and his flagship, the Quasar Fire-class cruiser-carrier Phoenix Nest, by ramming the Interdictor. This created an escape route for a rebel ship piloted by Ezra Bridger to warn others. The other cruiser, the Constrainer, was destroyed when rebel Mandalorian reinforcements ambushed the Constrainer from behind the 7th Fleet's formation and destroyed it with rockets. With both Interdictors eliminated, the remaining rebel forces were able to escape the 7th Fleet's blockade of Atollon. Years before the Battle of Yavin in 0 BBY, Lando Calrissian and L3-37 were ambushed by an Imperial interdictor in the Halthor sector while transporting a shipment of All Terrain Defense Turret walkers. Calrissian and L3 lost their entire cargo as a result of the ambush.

Between 2 BBY and 0 BBY, the Interdictor-class Star Destroyer, a modification of the Imperial-class Star Destroyer, was developed and put into service by the Imperial Navy. One such Interdictor Star Destroyer was under the command of Admiral Gable Karius above Mustafar, where it captured the smuggling ship Windfall.

By 0 ABY, the Empire had ceased manufacturing the Immobilizer 418 due to its vulnerabilities, preferring to integrate gravity well projectors onto Star Destroyers for increased protection. The Empire also discontinued production of the Interdictor-class heavy cruiser, as it proved to be an easy target for rebels and they again favored placing the projectors within Star Destroyers. Despite this, Immobilizer 418 cruisers remained in service throughout the galaxy due to their widespread availability. One Immobilizer managed to pull Luke Skywalker out of hyperspace into the Daalang system after he rescued a high-value asset from the Empire. However, due to the ship's frequent use against Alliance raiding parties, Luke Skywalker was able to devise a strategy to attack and ultimately destroy the vessel by splitting it in half with a Utheel Rockcrusher Compact Seismic Charge.

In 3 ABY, Hunter Fleet's secondary strike force deployed an Interdictor during a battle near Malastare against the Eighth Division of the Alliance Navy. Following the Syndicate War and other actions by Crimson Dawn, the Crimson Dawn flagship Vermillion attacked an Interdictor Star Destroyer. In 4 ABY, Interdictors were part of the Imperial forces during the Battle of Endor. The Imperial ships concealed themselves behind Endor and moved to prevent immediate escape, while the fleet's Interdictors activated their generators to fully trap the Alliance fleet. Alliance starfighters outmaneuvered the Imperial fleet and attacked the Interdictors and Imperial communications, and the DS-2 Death Star II Mobile Battle Station was ultimately destroyed. The surviving Imperial forces retreated as a result of the defeat.

In 5 ABY, the Interdictor-class cruiser Spectral participated in the Battle of Fondor Shipyards against the New Republic, and soon retreated to Jakku. During the retreat, one of its projectors was damaged by a Republic starfighter that managed to track the cruiser through hyperspace. Upon reaching Jakku's orbit, the starfighter was brought aboard and used to sabotage the ship, causing it to crash onto Jakku's surface. Shortly after, the New Republic Defense Fleet arrived and initiated the Battle of Jakku against the royalist Imperial forces, which consisted of at least three naval battle groups. The Immobilizer Glaciate participated in the battle, during which it was infiltrated and captured by New Republic operatives acting under the orders of General Carlist Rieekan. The battle resulted in the end of the Galactic Civil War and the final collapse of the Galactic Empire. Years later, scavengers from Niima Outpost attempted to explore the wreckage of the Spectral to loot it.

The concept of the Galactic Empire using Interdictor vessels to disable hyperspace travel first appeared in the Star Wars: The Roleplaying Game 1989 supplement Imperial Sourcebook and was later incorporated into Heir to the Empire, a 1991 novel by Timothy Zahn. This novel was the first in a trilogy that depicted events occurring several years after the conclusion of the final film of the original trilogy. While this trilogy is now part of the Star Wars Legends continuity and is no longer considered canon, Interdictor vessels have appeared in novels such as Tarkin and Heir to the Jedi, which are part of the new canon continuity.