The Imperial-class Star Destroyer is a design that is intended to inspire fear, and it succeeds admirably at that. There exists only a handful of threats which can seriously challenged even one of these ships. Through the deployment of an Imperial Star Destroyer and support ships to a system, virtually any foe can be neutralized. Except for combat or ceremonial purposes, it is abnormal for more than one ISD to be in a star system. Over 25,000 Imperial-class Star Destroyers had been commissioned as of the Battle of Endor. Half of which are held in reserve in the Galactic Core to guard critical military, industrial, and political systems. This reserve can be strategically deployed anywhere in the Galaxy on short notice. These warships form the core of the Imperial Navy.
A furious debate between the Imperial Navy's strategists, Imperial Military Oversight Commission and the now disbanded Senate Budgetary Committee erupted when Lira Wessex proposed to develop the ISD. She was but one of the driving forces behind this awesome vessel; her political clout assured through her marriage to Denn Wessex, one of the first Regional Governors. The ISD design is based on the VSD. While, Lira Wessex was able to replicate technology for large warships, she could not however do it as efficiently and inexpensively as Walex Blissex. Also, something in the VSD design eluded her, which has led to complications that may one day doom the Imperial Star Destroyer project. Some thought that the vessel was too unwieldy, some thought it was too expensive, while others thought the design was an engineering impossibility. Naturally, the Imperial Navy craved the design, and with a combination of political pressure, bribes, and a spate of mysteriously-crushed tracheas, everyone was gradually brought into line. The Imperial Navy was proven correct in its conviction when the first Imperial-class Star Destroyer, which was only 50 million credits over budget, rumbled out of dry dock and took active duty. By the Emperor's command, ISDs were constructed at such a rate that it forced all normal safety precautions to be discarded.
In the Imperial Order of Battle, an Imperial Star Destroyer is itself considered a line (theoretically a unit organization of four ships, in practice a line maintains one to twenty ships). According to a naval staff study, an ISD was the equivalent to at least a squadron of that era. While the Admiralty concurred with the study's findings, it did not agree with its conclusions. It believed that by designating the ISD as a squadron would serve only to reduce the number of ISDs it could obtain. Thus the Admiralty took the position that the warship was equivalent to a line, and therefore it got its wish, more Imperial Star Destroyers. For operational needs, ISDs can be grouped into a Task Force of three ships, six to a Sector Squadron, and twenty-four in a Sector Group.
The cost of a single Imperial Star Destroyer is enormous. It is known that there are entire star systems whose gross domestic product is beneath the price tag of one ISD. Nevertheless, for the Empire, the Imperial Star Destroyer has proven to be cost-effective, due to its awesome ability to maintain peace and order among the inhabited worlds of the Galaxy. Furthermore, in many ways, it is self-sufficient. A single Star Destroyer can take on a fleet of lesser vessels and expect victory. Due to the sheer size of the Galaxy, it is not possible to garrison every system within the Empire. However, ISDs give the Emperor the ability to project the Empire's power anywhere in the Galaxy on short notice, in order to expeditiously dispatch any opposition. Their appearance over Rebel-sympathetic worlds is often sufficient to quell uprisings. These vessels are the ubiquitous symbol of Imperial power.
Although its primary function is space combat, this warship's duties surpasses that of a weapons platform, as it serves in the planetary defence/assault, mobile space station and repair dock, command centre, diplomatic mission, and heavy transport roles. When accompanying Super Star Destroyers, it takes upon the escort role. Its wedge shape affords this design excellent fields of fire. Extensive firepower can be brought to bear, especially in the forward arc. The Star Destroyer's aft however, features few weapons and due to this, attacks against this arc are the preferred tactic by enemy forces. In engagements Rebel cruisers seek to attain a front or broadside position in the ISD's aft. In practice however, attaining such a position is extremely arduous. Furthermore, each of these warships feature heavy armour plating that is nearly two metres thick. A Mon Calamari Cruiser can cause trouble, and two such ships could perhaps defeat a single Imperial-class Star Destroyer.
Before entering combat, key equipment compartments are flooded with a Nitrogen-Carbon Dioxide mixture to protect them from fire. ISDs may participate in several actions simultaneously. For example, the ISD Vengeance in a single day would jump into one area to unleash TIE Fighters or landing craft, then jump to another to unleash additional craft or provide support. Most fleeing craft can be easily overtaken by this warship, shooting them into submission or drawing them into the main hanger with tractor beams. Its sophisticated sensor array can detect landed, small stock freighters on a planet's surface with infrared scanners should they venture beyond a half-kilometre from a large crash site (such as caused by a Nebulon-B Frigate).
Each ISD is equipped with redundant systems. Even in the case of a reactor failure power cells continue to power sections of the warship. And even those power cells are backed up by other power cells. For example, Level 90, Corridor R on the ISD Gnisnal was still powered even ten years after it was wrecked, by the Number Four power cell, which was backed up by the Number Eight power cell. Located on Level 96, Corridor Q section is the Number Four memory core. Under normal procedures, in the event that the ISD is to be lost, the memory cores are purged. The Number Four memory core is in its own high ceiling room, set against the wall. More than 40 work stations arrayed in two half-circles face the two metre tall memory core. On either side of the core, mounted on the wall are display panels that are as wide as blast doors. More than an a hundred Imperial data sequence algorithms are available to choose from when writing and reading data from the core. Without the proper algorithm, accessing the core only reveals streams of gibberish. Only the dual system controllers contain which algorithm was employed with the memory core.
Standard Imperial Fleet tactics generally dictate that ISDs be deployed for planetary assaults and invasion manoeuvres. In planetary assaults, a single ISD is sufficient to subdue an under developed world. When Imperial Command expects heavy opposition a task force of three ISDs along with additional transports are dispatched. Full planetary invasions against major industrialized worlds usually dictate that a full fleet composed of often six ISDs, heavy and light cruisers and carrier ships be employed. Eight ISDs are capable of overwhelming anything up to a Class Four planetary defence. Should the Empire not value the planet, there are two possible options. Imperial Army Troops instead of Stormtroopers will be deployed or the planet's surface will be reduced to piles of smoldering slag in a mere matter of hours. To facilitate long-term occupation of a world, an ISD can deploy its Pre-fabricated Garrison Base in a matter of days.
In order to operate the ISD at peak efficiency, its enormous crew of 37,085 is required. Note, this includes the Pre-fabricated Garrison Base personnel of 2,200. The aft third of the ISD requires a normal watch crew of approximately 7,400, while at battle stations approximately 12,000 crew is required. ISD crews were the elite of the galaxy at the height of the Empire. The reactor was one factor that determined the sheer size of this warship. Another being the space required to house the crew. Other space consuming elements include: engine turbines, backup engine reactors, subsidiary reactors, and anti-resonance plates. The auxiliary reactor can be found in the ship's nose. An amphitheatre with 150 seating capacity, vids and combat practice rooms are also maintained. A civilian area, with shops, services, eating establishments and leisure centres are found as well. Crew quarters include bedroom, living area with communications nook, and a small toilet room. Unlike most Imperial warships, the ISD provides recreational facilities for off-duty personnel. These multiple facilities are fairly large. Unfortunately, this design lacks raw material recycling facilities. As a result, most captains follow standard procedure and dump repair debris and waste materials before jumping into hyperspace. Raw materials and liquid stores can be found forward of, and flanking the secondary launch bay.
Both the primary and secondary launch bays are ventrally located, and are capable of accommodating hundreds of ships of varying sizes. The primary bay is of sufficient size for docking or capturing vessels that are 150 metres long or less. TIE squadrons, shuttles, landing barges, support and cargo ships, and probes are deployed from this bay. Armoured doors protect the TIE hanger bay and attack hanger which are located to the forward and aft of the primary launch bay respectively. Found within the primary bay is the electromagnetic paralyzing pincer crane (to immobilize captured ships) and flight control deck (at the aft end of the bay). Lining the port and starboard sides are retractable boarding tubes, magnetic field projectors and docking suspension field projectors.
Immense lift shafts connect the primary bay to forward interior bays and storage sections. Ceiling mounted transfer carriers move TIEs from the TIE landing bay (TIE hanger) to the service and refueling bays (there are at least six maintenance areas) that flank the TIE landing bay, and TIE launch hangers that line the flanks and aft of the primary launch bay. TIE Bombers are kept in the aft launch bays which are armoured compartments; to limit damage should their ordnance prematurely explode. The deck officer's office and preparation area can be found off of the hangers. Meanwhile, the smaller secondary bay, located in front of the primary deploys assault shuttles and senior officers' shuttles. In the event that the primary bay is put out of action, the secondary bay can take over TIE squadron duties. These bays are lit by phosphotube lighting, and colour-coded enunciators line the walls. Heavily armoured fuel canisters and lines can be found within the bays.
Propelling this warship through hyperspace is the largest hyperdrive unit to ever be manufactured. In fact, 123 ISD hyperdrive units were employed in the First Death Star to achieve that mobile battle station's class 4 hyperdrive rating. When entering hyperspace, a characteristic deck vibration can be felt. In a single hyperspace jump, the hyperdrive expends more raw energy than many planetary nations have during their entire history. Powering this mighty vessel of war is the solar ionization reactor, which is essentially a miniature sun. It provides more that sufficient levels of focused energy for any task. No shipboard power generator has yet to surpass it. It feeds the ship's hyperdrive, sublight engines, life-support systems, computers, powerfeed and weapons networks, and other systems at maximum levels while retaining a substantial reserve. It is because of the I-a2b reactor innovation that the ISD became a reality. Furthermore, because of the reactor, what is considered to be an obscene number of weapons could be mounted on this design. Three extremely powerful Destroyer-I Ion Engines provide sublight and hyperspace locomotion. Their output is powerful enough to incinerate a TIE Fighter. Four Gemon-4 Ion Engines provide thrust for emergency manoeuvres or in the event that the main engines are severely damaged.
Housed within the command tower are the bridge, computer controls, main computer, and other vital systems. Contained within the forward centre of the command tower is the main bridge, which features large viewports providing an impressive spectacle of the cold hard death of space. From here, navigation, hyperspace jumps, communications, weaponry, defences, tactical manoeuvres, and starfighter and troop deployment are controlled. Within the floor recessed computer pits, various controllers and specialists carry out their duties. In the "neck" of the command tower the officers' quarters and computer auxiliary power can be found. Sitting between the two shield generators is the tractor beam targeting array.
Sitting on top of the command tower are a pair of mighty shield generators that are encased in an armoured shell. Ringing the mid-section of the domes are sensor banks. A series of shield relays (appear to be vertical pointing rods) ring the dorsal section of each shield generator. Additional shield relays and deflector screen projectors are spread across the hull. These generators are capable of protecting the ISD from all but the most potent capital ship armaments. Unfortunately, when an ISD loses a shield, it cannot divert power to back-up shield systems. It must refocus its remaining shields to compensate. ISDs maintain at least four shields. Furthermore, in an emergency, the shields can be extended to cover a crippled fellow ISD.
Before the Battle of Yavin, the Rebels first discovered the ISD's shield weakness in their planning of the ISD Intrepid's destruction in their very first, direct assault against an Imperial capital ship (ISD). Destruction of the shield towers would leave an ISD vulnerable to barrages of proton torpedoes. Exactly how the Rebel technical staff unearthed the weakness is unknown. Unfortunately, the Rebels successfully destroyed the ISD Intrepid. The final time the Rebels were able to exploit this weakness (destruction of the shield generators on top of the command tower) was with the ISD Kotiate. After its destruction, the Empire subjected all of its ISDs to a time-consuming and expensive shield system upgrade to remove this grievous vulnerability.
On the topic of weaknesses, unfortunately there exists a spot within the drive section when precisely hit causes the ion drives to overload and detonate, taking the ship with it. This was exploited when the Rebels attacked and destroyed the ISD Havoc over the planet of Edan II, after sabotaging the aft shield generators. The aft shield generators are controlled from three power conversion nodes. Each of these nodes are manned via a small command chamber. Should all three nodes be destroyed (via by sabotage) then the aft shields will collapse. Meanwhile, in the case of the ISD Brazen, the Khuiumin Survivors (infamous pirates) concentrated their attack on the drive section. The lower port-side Gemon-4 engine was destroyed and the port and centre Destroyer-I engines were severely damaged. Due to the assault, extreme power surges swept the engines and propulsion shafts. At great sacrifice, the engineering crew managed to vent the energy away from the main reactor, but at a heavy loss of engineering crew. However, this only partially dispersed the power overload. Power feeds ruptured, armour plate disintegrated and segments of the superstructure buckled. When the ISD Brazen was destroyed via Rebel sabotage, three directionally focused bombs, each consisting of six proton torpedo warheads, were placed in key sections near or in the engines to accomplish the vile deed.
Flanking the command tower are the heavy turbolaser battery turrets and heavy ion cannon turrets (most aft turrets). Below each 50 metre-diameter turret is its power cells. Their auxiliary power cells are adjacently located, as are their cooling system pumps. Behind proton-shielded armour plates (that are located behind the turrets) are the weapons' fire control, targeting level, and power feed and modulation control; with each occupying their own level (story). These heavy turbolaser battery turrets are capable of overloading deflector shields and piercing holes in even the most heavily armoured warships. Although the weapons have trouble tracking small, fast moving ships, a glancing blow will destroy them. In the trench on either side of the command tower are a pair of lateral quad-laser batteries. Along the ship's axis, at the area where the structure starts to rise up from the hull (around the midpoint of the ISD) are three linearly placed axial defence turrets. Located in the nose are the pursuit tractor beams, their power cells, the navigational deflector generator.
Due to the immense heat given off by the XX-9 Turbolasers, three separate cryogenic cooling systems are mandatory in order to keep them within safe thermal thresholds. The turbolasers and ion cannons are mounted in five-gun batteries. Each battery is composed of three turrets, with two being dual-mounted, and the remainder being single-mounted. These batteries, controlled by a gunnery sergeant (who is safe within the ISD's depths), are linked into their own advanced fire-control systems to ensure the weapons fire in sustained, organized volleys. This arrangement allows for the concentration of fire against a single target or the independent engagement of multiple targets by each turret in a battery. While this configuration is sufficient against other combat starships, it does suffer a significant drawback against small targets at close range. Nonetheless, the XX-9s were equipped with advanced targeting technology to allow the weapons to be employed against swift-moving starfighters. Gunnery control stations allow the concentration of fire from several ion cannons upon a single target, which often disables it in the opening volley. Some captains employ the tractor beams to immobilize the ionized vessel, and then swiftly destroy it with turbolasers before a distress signal can be sent.
The aft section of an ISD consists of reinforced superstructure and reinforced support columns that are honeycombed with powerfeeds. Durasteel armour protects the access tunnels and control spaces. These sections are invulnerable to sabotage and can only be internally accessed. Bulkheads separate engines from their power cells and propulsion shaft feeds. At least a pair of power overload suppressors equips each Destroyer-I engine. Each propulsion shaft features its own force fields to prevent explosions from reaching the main reactor. Additionally, they also possess enormous radiation blast doors that are both locked and monitored by vid cameras. The access tunnels at the engines are 20 metres in diameter, the tunnel eventually narrows to 1.5 metres in diameter at the main reactor junction.
Before the debacle at the Battle of Yavin, funds were in place to retrofit the remaining ISDs with TIE flight decks (since most, but not all ISDs were such equipped). However, due to the circumstances surrounding the loss of the first Death Star, the possibility existed that the budgeted funds could be diverted to more vital objectives.
Every Imperial Star Destroyer, by the Emperor's decree includes a thrown room for his exclusive usage. Thereby allowing the Emperor to maintain control over the Empire regardless of his location. This practice of including thrown rooms in warships that were Imperial-class or better, started with this class of ship. To ensure that the Emperor nor his top agents could not be denied access to any Imperial Star Destroyer, each warship's main computer had a "backdoor" hardwired into the system; impossible to eliminate. Access to the backdoor was by a confidential password. This backdoor would allow the user to access or manipulate any records or systems. This knowledge was known only to a handful of people, such as the Emperor's Hands. Should the main computer be deactivated, so to is the "backdoor", and conversely the warship is also effectively disabled.
ISDs are able to shut down their transponder signals in order to decrease the possibility of detection while on the move, and when entering a star system. During the era of the Empire, this was considered unorthodox and unacceptable, but ISB Central Commander Sollaine employed such a gambit when attempting to capture a very-well placed Rebel spy with the ISD Devastator, shortly after the SSD Executor was commissioned. At the time of the Black Fleet Crisis (12 years and 8 months after Endor), even the best passive sensors available could not detect an ISD against the background of a first-magnitude star at a range of only 6,000 kilometres.
Located almost forward of the main reactor is the detention area. The detention block (most likely a detention area segment) contains two rows with nine cells each. These cubical cells are three metres per face. Each is adorned by steel grids in the ceiling protecting light fixtures, retractable sleeping pallet of soft foam, waste disposal unit, and a surveillance camera mounted in the wall, which is protected by an unbreakable sheet of clear plastic. Communication between prisoners is impossible. In the event of a power failure (that would disable the electronic locks), cell doors are also equipped with manual locks to ensure that prisoners cannot escape. Further note, during a power failure the blast doors and airlocks can be opened via clearly labeled manual controls. In the case of the ship grapple, at the grapple joint is the manual release. Located behind the detention block guard station is a vertical access shaft, from which perpendicular access ducts containing power relays can be found. From the detention block to the central companion way is 30 metres down. From that point, it is 250 metres (horizontally) to the airlock staging area, and ultimately the docking bay.
*After Endor* Most Imperial Star Destroyers no longer carry their originally assigned complements due to shortages plaguing the remainder of the Empire (as of five years after Endor). Unfortunately, ISD losses continued to mount. A year after the Battle of Endor, the SSD Guardian and three Imperial-class Star Destroyers participated in the Battle of Tantive V. While the SSD Guardian managed to escape destruction, two ISDs were destroyed, while the third, the Wolf's Claw was captured and later incorporated into the Rebel Fleet. Before the Hapans and the New Republic joined forces, the Hapans had somehow managed to capture dozens of ISDs. Nevertheless, the New Republic operated a number of Imperial-class Star Destroyers, examples are the ISD Indomitable and Rebel Dream. Eight years after the Battle of Endor, Supreme Warlord Harrsk constructed a dozen ISDs. Ten years after Grand Admiral Thrawn's most untimely death, there were nearly 200 Star Destroyers remaining in Imperial hands, out of a fleet that once numbered over 25,000. At the same time it is also known that the New Republic continues to employ this warship.
Sources: AGSWU2***Pg 414, 415 / AJ4***Pg 213-217 / AJ10***Pg 231, 232 / AJ11***Pg 30, 31, 34, 46, 47 / AJ12***Pg 120 (timeline placement), 128, 133, 134 / BFCT#1***Pg 1, 7, 123, 124, 126-129, 132, 143 / BFCT#2***Pg 85 / BFCT#3***Pg 194 / BTM+Technology+Vehicles+Capital Ships+Imperial Star Destroyer / CA-V5***Pg 6-8 / CE (Scene where ISD Steadfast is attacked by Rogue Squadron) / CRB***Pg 186 / D***Pg 65, 80 / DSTC***Pg 74 / EGVV***Pg 80, 81 / EGWT***Pg 82-88, 116, 118, 136, 138 / FC (Cinematics Text - found on CD), (Gameplay) / GG3***Pg 45 / GMSR***Pg 39 / IAG***Pg 55, 57-59, 61 / ICS***Pg 6, 7 / ISB***Pg 105, 131, 136, 137 / NEGVV***Pg 142, 143 / NEGWT***Pg 70, 71, 78, 79, 82, 83, 110, 111, 139, 143 / OE***Pg 95, 96, 109, 111 / RASB***Pg 53 / RESB***Pg 45, 75 / RPG2E***Pg 118, 119 / RPG2RE***Pg 252 / S***Pg 3, 4 / SESWTSB***Pg 114, 137-139, 141, 142 / SFS***Pg 2 / SOTG***Pg 61 / starwars.com+Databank+Starship+Imperial Star Destroyer / starwars.com+Databank+Starship+Republic Attack Cruiser / SWE+Star Destroyer***Pg 284 / SWSB***Pg 32-35 / SWSB2***Pg 29, 34-37 / TCOPL***Pg 1, 3, 24, 80, 82, 114 / TESB! (Scene where Millennium Falcon disappears from the ISD Avenger's scopes), (Scene where ISD Avenger releases its garbage) / THOTD#1***Pg 2, 6, 17, 141, 186, 308 / THOTD#2***Pg 17, 140, 141 / TIE-SC***Pg 19, 25, 28, 40, 90 / TJ***Pg 81-91, 100 / TT#2***Pg 282-284, 320, 329, 330 / TTSB***Pg 219 / XA (Tech Library) / XvsT (Craft Database), (Imperial Task Force Vengeance: Cover Imperial Starfighter Replenishment at Essebra) / XW (Bonus Mission 3), (Tour 2 Mission 10) / WBC***Pg 4, 7 / CCG=Dagobah Limited ExpansionSet+Dark Side+Defensive Fire / CCG=Death Star II Cards+Dark Side+Accuser / CCG=Death Star II Cards+Dark Side+Judicator / CCG=Death Star II Cards+Dark Side+Visage / CCG=Jedi Knights-Premiere+Devastator / CCG=Premiere Set+Dark Side+Devastator / CCG=Second Anthology Preview Cards+Dark Side+Thunderflare / CCG=Special Edition Limited Expansion Set+Dark Side+Vengeance