The Imperial I-class Star Destroyer, also known as the Imperial I-class Destroyer or the Imperator-class Star Destroyer, was an iconic class of warships designed by Lira Wessex and built by Kuat Drive Yards. The Imperial-class Star Destroyers, along with Imperial stormtroopers, represented the might of the Imperial Military throughout the galaxy during the reign of the Galactic Empire.
Imperial I-class Star Destroyer
- Taim & Bak XX-9 heavy turbolasers(60)
- Borstel NK-7 ion cannons (60)
- Dual heavy turbolaser turrets (6)
- Dual heavy ion cannon turrets (2)
- Quad heavy turbolasers (2)
- Triple medium turbolasers (3)
- Medium turbolasers (2)
- Phylon Q7 tractor beam projectors (10)
Post Battle of Hoth refit:
- TIE/LN starfighters (36)
- TIE/IN interceptors(24)
- TIE/sa bombers (12)
- Lambda-class shuttles (8)
- Delta-class stormtrooper transports(15)
- Assault gunboats (5)
- A variable number of Skipray Blastboats
- Gamma-class assault shuttle (1+)
- Repair and recovery vehicles
- Theta-class AT-AT barges
- Sentinel-class landing craft (12)
- AT-AT walkers (20)
- AT-ST walkers (30)
- Prefabricated garrison base (1)
- Galactic Republic
- Galactic Empire
- New Republic
- Imperial Remnant
- Galactic Federation of Free Alliances
- ConfederationThe Imperator-class was originally used by the Republic Navy toward the end of the Clone Wars, and served alongside the Tector-class in a few task forces during the conflict. It was at the time one of the largest warship classes in the Republic Navy. It later became a mainstay of the Imperial Navy and was also fielded to a lesser degree by the Empire’s successor-states.
- “Half the budget is going to the production of these enormous new Star Destroyers.“
- ―Mon Mothma
The Imperial I-class belonged to the Star Destroyer family of warship, exemplified by its dagger/arrowhead design. A single Imperial-class vessel cost the Empire more than twenty times the cost of a EF76 Nebulon-B escort frigate, which was the equivalent of several star systems‘ annual economic output.
The Imperial-class was produced in large numbers and was the premier warship class of the Galactic Empire. All known variants were 1,600 meters long (one mile). Compared to most common frigates and downscaled cruisers known from the days of the Old Republic, the Imperial-class was a huge warship, but in the Imperial Navy, it was one of the Empire’s mid-sized mainline warships, like its predecessor had been for the Republic. The hulls of the Imperial-class were painted in Star Destroyer White, a purely economic choice as it was the only variety of paint that was produced in sufficient quantities to coat the Empire’s immense number of warships.
According to officially available statistics, Imperial-class Star Destroyers had at least 37,000 officers and crew. Counting the stormtrooper complement (one division or legion, 9,700 men) would total 46,700. This would include a stormtrooper detachment, starfighter pilots, and support craft pilots. Differing from many other Imperial vessels, recreational facilities provided entertainment for off-duty personnel and “guest rooms’ could accommodate Imperial VIPs.
Offensive and defensive systems Cross-section showing from left to right: Main gun batteries, an auxiliary reactor, main hypermatter reactor core, docking and hangar bays, storage areas, tractor beamprojectors.
Like with several other Star Destroyer classes, the designers did not take advantage of their wedge shape to give the heavy cannons the ability to focus on targets in the forward firing arc that were level with the ship. This could have been accomplished either by superelevating the aft turrets, or merely by spacing the turrets apart over a longer distance of the ship’s length. In any case, this Star Destroyer class could bring all its heavy guns to bear by dipping its bow downward.
Numerous smaller and medium guns were mounted around the ship to ward off attacks against lesser ships not capable of being targeted by the main battery. They varied in size; some were designed as point-defense cannon to destroy incoming missiles and starfighters while others engaged lesser capital ships. Some ships, such as Emancipator, were refitted with proton torpedo launchers. Three triple-gun turrets were mounted on the ridge of the ship, just forward of the lowest, forwardmost terrace of the dorsal superstructure.
The standard wing included four TIE Fighter squadrons (one squadron often referred to be a reconnaissance squadron of TIE/rc starfighters), one squadron of TIE Interceptors, one squadron of TIE Bombers (lower priority ships had to make do with TIE/gt starfighter-bombers). Often one or two flights in a fighter squadron were TIE/fc starfighters. Sometimes one of the fighter squadrons was used for training purposes. By the Battle of Endor, one of these fighter squadrons had been phased out in favor of a second squadron of TIE Interceptors. Imperial I-class Star Destroyer in a planet’s atmosphere.
The attack hangar was located on the underside on the ship and was guarded by a set of armored doors. TIE fighter service and refueling bays, and TIE launch hangars surrounded the main hangar. TIEs were launched from cycling racks and pilots boarded from overhead gantries and were released into space as they disengaged from the front position in the racks.
Returning fighters landed in separate hangars and then were guided by small tractor beams into receiver-carriers. The receivers carried the TIE to a debarkation station where the pilot would exit. Once moved through the transfer tunnels to a launch hangar, the fighter could be serviced and refueled in a separate bay. In the hangar, the TIEs were cycled through a launch rack and ready for the next launch. The small forward hangar was for shuttle craft carrying high-ranking officials. The forward hangar was also used as a back-up to the main hangar.
These ships carried 9,700 troops, as well as massive war vehicles such as AT-AT and AT-ST walkers. AT-AT barges and other landing craft were used to deliver ground assault forces to a planet’s surface.Although larger landing craft could only be carried onboard bigger Imperial vessels, the Imperial-class could transfer a large number of heavy walkers to smaller transport ships via a detachable rail system.
The Star Destroyer could use its guns and TIE starfighters to support any surface action. If a planet required a lasting presence, a Star Destroyer could quickly deploy a prefabricated garrison base. Like most other Star Destroyer models, the Imperial-class was capable of entering atmospheres and supporting ground operations directly.
There were entire planets that, throughout their history, did not expend as much power as an Imperial-class ship did in one hyperspacejump. The hyperspace generator was located along the ship’s ventral surface. A massive solar ionization reactor bulged from the ventral spine, annihilating hypermatter as fuel to power the ship. Auxiliary reactors flanked the main reactor and the three reactors were connected to the three main engines. In addition, the backup engines were connected to additional reactors as well.
As designed, the Imperial-class had a Class 2 hyperdrive with a Class 8 emergency backup. However, KDY’s practice of subcontracting out the design to meet Imperial demands led to occasional design quirks: Star Destroyers built by the Corellian Engineering Corporation were considerably faster, both at sublight and hyperspace speeds.
For sublight propulsion, the Imperial-class relied on an array of three primary Destroyer-I ion engines produced by KDY specifically for the vessels. For emergency situations requiring additional thrust, the Imperial-class could use its four Gemon-4 ion engines. The engines were capable of accelerating the ship with a force of several thousand g.
The command bridge tower of the Imperial-class Star Destroyer was massive, and the command bridge followed a design similar to that of many other KDY warship classes, such as the Venator-class, the Executor-class designs. The sensor array on top of the Mk. I’s tower had support beams running diagonally across it. These would later be substituted for vertical ones during a minor refit, which made the array look similar to the one on Mk. II vessels. The two globes atop the bridge tower served two purposes: aiding both in hyperspace communication and deflector shield generation. The proximity of the deflector shield generators made the bridge tower one of the most protected parts of the Star Destroyer
- “I hate the look of these new mass-produced Imperator-class Destroyers. None of the artistry that went into the old Acclamators or Venators—even the Victory Twos. So goes elegance.“
- ―Brudi Gayn
The Imperator-class was designed as a massive, powerful, mid-sized warship,, and appeared in limited numbers during the Clone Wars, where it served in several Republic task forces. As the war neared its end in 19 BBY, the production lines of new Imperator-class and Tector-class destroyers expanded, while the lines for the older, lighter Venator-class slowed down.
The first vessel was named the Executrix, while the second was the Exactor, which later served as the first personal flagship of the Imperial enforcer Darth Vader. There was also an Imperator among the Mk.I models, sharing the class name. Following the Great Jedi Purge and the establishment of the Galactic Empire in 19 BBY, the Imperator model was renamed Imperial-class and production of the class was increased even further and refined. Despite the name change, some Imperial documents continued to use the original name to identify the class.
Imperial-class Star Destroyers had a distinguished career in the Imperial Starfleet, where they symbolized the Empire’s military might (for better or worse). Eventually, these Star Destroyers rendered older vessels, like the Venator-class, obsolete.
Capable of laying waste to entire worlds (provided those worlds did not have planetary shields), the Imperial-class became infamous as the prime enforcer of Imperial rule, and even served as a small, peacekeeping battleship. According to official records, over 25,000 were eventually produced. The Navy’s immense demand for Star Destroyers led Kuat Drive Yards to subcontract the design out to various other shipwrights, which occasionally led to a number of design quirks: Star Destroyers built by the Corellian Engineering Corporation were considered the fastest ships in the Imperial Navy, both at sublight and hyperspace speeds. Many Star Destroyers were destroyed in the fratricidal warfare that consumed the Empire after the death of Emperor Palpatine at Endor in 4 ABY, while others defected or were captured over the years.
Within sector-level fleets, the ISD served a central battleship role, being the flagship of the unit known as the “Battle Squadron.” A Sector Group was responsible for patrolling a given sector and was composed of 24 Star Destroyers. It was also observed to operate more or less independently and often far from support ships and facilities. Through many operations, the ISD functioned as a destroyer, a capital ship fast enough to chase down blockade runners and protect fleets. As an escort, it also supported Imperial Star Cruisers and Star Dreadnoughts in fleet combat.
When he assaulted Hoth, Darth Vader commanded the Star Dreadnought Executor and brought along a flotillaof Imperial-class vessels from Death Squadron to assault the planet. The Rebellion’s heavy ion cannon, powered by the reactor of a battlecruiser, easily overwhelmed individual Star Destroyer shields and rapidly disabled ships in orbit.
In the New Republic era, Imperial-class Star Destroyers continued in the escort role for larger vessels in campaigns like Operation Shadow Hand in 10 ABY. The Super Star Destroyer Allegiance led a task force of Imperial-class ships and World Devastators during the First Battle of Mon Calamari. This was one of many fleets that struck out from the Core as part of the operation, which was aimed at taking back most of the Galactic Empire’s former territories. Operation Shadow Hand saw a relatively heavy use of different types of Super Star Destroyers supported by Star Destroyers.
However, due to lack of logistics, not all Imperial splinter factions made use of Super Star Destroyers. For instance, Grand Admiral Thrawn massed a sizable force in 9 ABY, but could not obtain any larger warships. In those instances, Star Destroyers like the Imperial-class acted as main command ships of a navy.
This particular class of vessel saw extensive service in other navies, including that of the successor-states the New Republic and the Galactic Alliance. Some New Republic Imperial I-class Star Destroyers, like the Mon Mothma, were refitted to include gravity well projectors.
One Star Destroyer was operated by a private individual—the Errant Venture, formerly the Virulence, which had been captained by the smuggler Booster Terrik. The warship was claimed by Booster in the wake of the decisive Battle of Thyferra that concluded the Bacta War, but was in poor condition for many years owing to the great cost of maintaining such a large vessel. In addition, she was stripped of the vast majority of her armament: only ten turbolasers were permitted, and even those were not always functional.
Years later, the vessel received a comprehensive refit in exchange for Booster permitting its use in a New Republic special-operations raid on an Imperial base. The most notable part of this refit was a deep red paint job instead of the classic Imperial white. While Captain Terrik was not permitted to keep all of his weapons after the operation, they were reinstated when the Yuuzhan Vong War occurred. During the Yuuzhan Vonginvasion, she served as a temporary Jedi sanctuary and also as squadron flagship.
Imperial II-class Star Destroyer
Several variant designs and refits were made using the Imperial-class as a basis. The most famous and widely produced, was the Imperial II-class Star Destroyer, the second iteration of the class. It included improved armor and weaponry, a different sensor tower and other cosmetic differences.
Similar to how some Victory-class vessels borrowed design elements from the Imperial-class, at least one Imperial variant borrowed elements of the Victory-class. It had an elongated command tower and wing-structures on the side of the superstructure.
Interdictor-class Star Destroyer
Another variant was the Interdictor-class Star Destroyer, heavily modified Imperial-class ships that were fitted with gravity-well generators and utilized to halt hyperspace travel for enemy ships.
Behind the scenes
There has been some disagreement over the name of the class. Early material by Geoffrey Mandel, now considered unofficial, showed the Star Destroyer model smaller than they later appeared. The class-name Imperator was used for these drawings, and the ships were to be produced at the Gyndine shipyards. Many of the designs were greatly upscaled shortly before production began. Some critics suggest that naming one of the Empire’s class of ships Imperial is redundancy in name.
Star Wars: Revenge of the Sith Incredible Cross-Sections eventually put the debate to rest, by clarifying the issue—while the class was originally named Imperator, it was renamed Imperial at some point after the Great Jedi Purge. Other sources would later on reference Imperator, including the novel Dark Lord: The Rise of Darth Vader and the EU-section on the Venator-class Star Destroyer’s . The word “Imperator” is Latin and was used as a title for “An army commander in the Roman Republic”. Later, during the Roman Empire, it became a title worn by the Emperors and signified “The supreme power of the Roman emperor”.
Based on an animatic of a Revenge of the Sith TV spot, an Imperator-class Star Destroyer was scheduled to make an appearance during the final scenes of the film, but was apparently cut out and replaced with a Venator-class in post-production.
Imperial-class Star Destroyers have featured prominently in many Star Wars computer games. However, they have generally been “toned-down” to allow the player some chance of defeating them with a starfighter. Some of these game mechanics have included shooting sensor globes and reactor bulbs with your starfighter to bring down the whole ship.
Imperial-class Star Destroyers have sometimes been referred to as cruisers. The book Starships of the Galaxy(Saga Edition) referred to most common Star Destroyers as being classified as “star cruisers”, with lowercase letters. It also noted that unlike the term “Star Destroyer”, “star cruiser” means “a naval cruiser that travels through space”. Since the Imperial-class has also been called a “star destroyer”, the class can be seen as either a naval destroyer or a cruiser, given similarities in their roles. Imperial-class ships have also been described as battleships (more specifically, “peacekeeping battleships”). This is presumably because one Imperial constituted a line on its own. RotS:ICS also mention warships being “downscaled”, depicting at least two separate classification systems, one where regular Star Destroyers are destroyers and another where they are battleships.
Numerous Expanded Universe sources state that the Imperial I is armed with 60 identical turbolasers and 60 identical ion cannons. However, analysis of the Star Destroyer models used in the films shows that this is a flawed description. The Star Wars: Incredible Cross-Sections factbook followed the movie model more closely, describing three twin-barreled heavy turbolasers and one ion cannon on each side of the command tower, one quad-laser cannon in each side trench, three cannons in front of the terrace superstructure, and numerous smaller guns lining each trench, as well as several tractor beam projectors located inside the vessel.
The Star Wars Technical Journal offers a slightly different number for the crew requirement: 4,520 officers and 32,565 enlisted men making a total crew of 37,085.