BC-304

"It has a few advantages over the Prometheus. The more advanced alien technologies were integrated into the original design rather than tacked on after the fact."

- Samantha Carter

The BC-304, also known as the Daedalus-class warship, is a class of deep space carrier built by the Tau'ri, and the most advanced series of vessels in the Tau'ri fleet. As of 2010, six Daedalus-class warships have been built. These include the Daedalus, Odyssey, Korolev, Apollo, Sun Tzu, and George Hammond. All but two are operated by the United States Air Force. One 304, the Korolev, was given to the Russian Federation, and subsequently lost in a battle with the Ori, while another 304, the Sun Tzu, is operated by the Chinese Government.

Overview
Although referred to as "sister ships" to the BC-303 Prometheus, the BC-304s differ significantly in their design and technology. While the Prometheus was originally built with reverse-engineered Goa'uld technology and salvaged equipment, the BC-304s incorporated Asgard technology in their original design; All 304 class ships are equipped with Asgard shields, sensors, transporters, as well as intergalactic hyperdrive technology that allow the ships to make large intergalactic journeys in a matter of days.

While the Asgard initially refused to install Asgard-designed weapons on the BC-304, Asgard plasma beam weapons were gifted to the Tau'ri in 2007 as part of a larger refit to the class. Earth's flagship, the Odyssey, was the first to receive these upgrades, followed by the Daedalus and Apollo shortly thereafter. Since 2007, these upgrades have been incorporated into the base design of all new BC-304s in production.

While built along similar lines to other members of the class, the George Hammond (completed in 2009) was built from the outset as an upgraded version of the Daedalus-class; The George Hammond possessed a heavier superstructure around the bridge, larger and wider 302 Bays, improved reverse thrusters that enabled it to land in smaller spaces easier, and a new, more-powerful series of railguns.

History
Earth's first battlecruiser, the Prometheus, initially proved itself to be a capable warship, with several ships of the BC-303-class planned for production. However, over the course of the ship's lifespan, several improvements were made, with the Asgard installing several new systems in a show of gratitude for the Tau'ri's help in battling the Replicators. With the addition of these upgrades, and the great technological strides made by the Tau'ri in general since Prometheus was originally constructed, it soon became apparent that using the original BC-303 design as a template from which to construct new ships was impractical. Therefore, a new spaceship, intended to be built from the ground up with these upgrades, was designed.

The construction of this new class of ship, known as the BC-304, immediately became one of Stargate Command's most important projects. Currently, seventy percent of the SGC's operating budget has been transferred to the construction of Daedalus-class vessels, with each vessel costing seven billion dollars. The first vessel of the class was the Daedalus, which was introduced in 2005. Upon its completion, the ship was immediately assigned to the Pegasus galaxy to assist the Atlantis expedition in the Tau'ri-Wraith war.

The following year, in 2006, the second Daedalus-class ship, the Odyssey, was constructed. The ship's initial mission was to deal with the Lucian Alliance and, foremost, the forces of the Ori, which had invaded the galaxy.

The first two Daedalus-class ships were commanded by the United States Air Force. However, when the Ori invaded the Milky Way a third Daedalus-class ship was near completion. The Korolev was given to the Russians as a "trade agreement" for the United States of America to continue running the SGC with the Alpha Gate, which was on lease from Russia. The Korolev was destroyed during the Battle of P3Y-229 soon after being rushed into service.

In 2007, when faced with the extinction of their race, the Asgard gave the Tau'ri their complete knowledge base in the form of the Asgard computer core. They also gave the Tau'ri vessel, Odyssey, a mass-upgrade. Since that historic event all Daedalus-class warships have been outfitted with Asgard advancements, in the form of Asgard plasma beam weapons. These weapons have given the Tau'ri a military superiority over most other known races in the universe.

Another Daedalus-class ship, the Apollo was constructed later in 2007. It was stationed around Earth in defense against a potential Ori attack. The attack never took place however, and it was subsequently assigned to the Pegasus galaxy to fight the Asurans in the Asuran-Tau'ri-Wraith war.

The next 304 in line, the Sun Tzu, was put into service by China in early 2009. In its first mission, the Sun Tzu and the Apollo jointly engaged the Super-hive, which had found the location of Earth. The attack was a failure and both the ships were crippled in battle. The Hive ship was subsequently destroyed over Earth.

Additionally, Earth's sixth 304, the George Hammond (introduced in an alternate timeline as the "Phoenix"), was completed in 2009 and is placed under the command of Colonel Samantha Carter. It later took part in the defense of Icarus Base and other Lucian Alliance conflicts. . It was additionally assigned to the Pegasus galaxy to assist in the Tau'ri's conflict with the Wraith.

Bridge
The bridge of the BC-304 is located in the structure at the beginning of the ship's neck.[Note] While BC-304s differ significantly in several key aspects from the BC-303, the bridge layout is relatively similar. The forward view port has been redesigned and is wider to allow a greater visual field. This is particularly useful during battle situations, allowing several officers to make suggestions about how to proceed without obstructing the captain's chair. Also built into the forward view port is a Heads up display.

The captain's chair is located in the front section of the bridge and is centered several meters behind the forward view port. A weapons officer sits to the right of the captain, a helmsman to the left. These are the only chairs present on the bridge, with the remaining bridge terminals being operated from the standing position. A large map display is located in the rear section of the bridge. This display is illuminated in a different color for each BC-304, being green on the Daedalus, orange on the Odyssey, white on the Apollo, purple of the Korolev, and orange on the George Hammond.

Originally, a static illuminated panel was integrated into the right and left walls of the bridge's forward section. These have since been replaced with a plaque that denotes the identity of the particular BC-304 on the right wall, and a computer terminal on the left wall.[Note]

Engineering
The engineering deck consists of a small room containing a number of computer terminals and displays. As of the refit to the class in 2007, a large Asgard terminal is located in engineering. It is large enough to accommodate approximately a dozen personnel at any given time. A view port overlooking the Asgard hyperdrive can be found at the aft end of the chamber. Tasks from systems diagnostics to the deployment of weapons can be carried out here.

Hangar bay
BC-304s possess two large hangar bays - one located on each side of the ship. They are able to carry twice as many F-302 fighter-interceptors as the BC-303 — eight in each of its two hangar bays, for a total of 16. However, while some BC-304s are known to carry a full complement, the Daedalus has occasionally been seen carrying fighters only in its starboard hangar. The hangars of the BC-304 are large enough to accommodate a number of other ships, including puddle jumpers and Wraith scout ships. Additionally, an Al'kesh is able to barely fit into the hangar bay.

The entrance of each hangar possesses a large airtight bulkhead. Once opened, a shield is projected over each hangar bay door. This shield allows for the passage of F-302s into and out of the bay while active, while simultaneously preventing decompression from occurring. This shield appears to operate independently of the BC-304's main shield system; it is projected as a plane over the hangar bay doors, whereas the ship's main shield forms a bubble around the entire vessel.

Infirmary
The Infirmary onboard the BC-304s are nearly identical to the infirmary of the BC-303. They contain several rooms with hospital beds and are stocked with all manner of medications and equipment for the crew members. A surgical suite is also part of the infirmary.

Bomb bay
At least one 304, the Apollo, features a large bomb bay built into the underside of the ship, capable of deploying the Horizon weapons platform. A control room just aft of the bay includes a set of observation windows, arranged much like the ship's engine room. It is unclear whether any other BC-304s also possesses such a bay, or if the Apollo constitutes a new variant of the class.

Mess hall
As the BC-304s are designed for extensive deep-space voyages, a mess hall is available to off-duty personnel. It is located on the starboard side of the ship, offering a view port into space. Hot coffee other drinks are available in the mess, no matter the time of day.

Observation deck
BC-304s posses at least one observation deck. Such rooms are located against the outer walls of the ship, consisting of a large window as to allow for a wide view into space. A large padded bench stands a few feet behind this window. A computer display is mounted into the wall directly opposite the main window and is surrounded by a computer terminal.

Brig
The brig on a 304 is a small, unadorned room not dissimilar to the ship's storage compartments. It contains a surveillance camera through which the prisoners can be observed. The brig is furnished with a small metal bench and a small sink that rests on top of a cabinet. Though apparently designed for only a single occupant, it has been used to hold up to four people, indicating there may be only one such room on the ship.

Cargo holds
While the hangar bays of the BC-304 are often used to store cargo, BC-304s additionally possess a number of smaller, independent cargo holds. Some of these can be quite large, easily accommodating upward of thirty crew members; Such holds are often used to store a variety of industrial equipment. Other, much smaller, holds have been used to store food.

Briefing Room
BC-304s are designed with a briefing room in which the captain can meet with senior officers for briefing before difficult/complex or strategic operations. The 304s' briefing room is a spacious room with a high ceiling, paneled in gray tones and equipped with large florescent lighting fixtures on the ceiling. It is dominated with a large black meeting table, and lined with several chairs along the sides. Behind the captain's chair is a large flat screen monitor built into the wall. As a screensaver, it displays the seal of the ship with the ship name at the top and the registry number of the ship along the bottom. Screens are additionally positioned around the room.

Asgard knowledge room
Following the retrofit of the Odyssey conducted by the Asgard in 2007, a small, curved room containing a small terminal is present on the ship. From this terminal, a holographic display can be activated, which wraps around the entire room. This holographic display is linked to the Asgard computer core and can be used as an interface to interact with the information stored inside it. It is unknown if other BC-304s were similarly equipped with such room.

Crew Quarters
The BC-304 contains a number of relatively spacious crew quarters. While the location and the number of them are unknown, several are positioned along the hull of the ship, allowing for a view into space via a small window. The rooms are equipped with recessed lighting and are large enough to accommodate a variety of furnishing.

Armory
There are several armories on the BC-304. These armories consist small rooms in which various weapons and munitions are stored; They are known to contain Tau'ri, Goa'uld and Wraith weapons, in addition to vests, radios, equipment cases, and a variety of other supplies. The armories also include several lockers assigned to each SG team and team member.

Airlocks
Several airlocks line the slender midsection of the BC-304. Airlocks may be vented through initiating a venting sequence controlled through the ship's computer consoles, or by performing a manual override to open the door via a control keypad. The airlock itself is composed of two doors (one inner, one outer) between which is a small space large enough for two people. Attached to the walls inside this space is a phone, a small computer display, and two large yellow lights that illuminate once the sequence to open the outer door has been initiated.

Gym
The BC-304 is equipped with a gym containing a variety of exercise equipment including treadmills, exercise bikes, and weights. The gym is located in a large room with a high ceiling. The room's center is large and open, which provides ample space for crew members to spar.

Technology
The BC-304s boast a large amount of incredibly advanced technology, most of which came from the Asgard, which helps make BC-304s a formidable craft, capable of rivaling the spaceships of most races. In contrast to its predecessor, the BC-303, the new Daedalus-class ships had several significant advantages in that the more advanced alien technologies were integrated into the original design rather than added on afterwards.

Sensors
The BC-304s feature a Long-range transmitter, located with a series of other communications-related equipment, including Asgard sensors, at the top-rear port section of the ship. There are also sensors located on the nose section of the ship. These sensors are highly advanced as they can scan and pinpoint life signs from far away, and are also what allows the Asgard transporters to lock on to an object accurately.

Shields
Energy shields are the primary defense technology used by 304s. The technology was shared by the Asgard with the Tau'ri after their contributions in defeating the Replicators, and so the Earth-designed Daedalus-class warships are protected by Asgard shields, giving them a great advantage over the space-faring races of both the Milky Way and Pegasus galaxies.

Asgard shields create an elliptical "bubble" around a spaceship that absorbs and diffuses the energy from weapons fire. The shields will gradually weaken under sustained fire, rather quickly if the attack is of sufficient force, allowing energy from attacks to bleed through and cause damage to the ship. Although additional energy can be allocated to the shield bubble to reinforce it, the only way for a ship to ultimately survive a continual attack is to withdraw and give the shields time to recharge.

Asgard transporters
The Asgard first allowed the Tau'ri access to a very basic form of their beaming technology, which they included on the Prometheus during a refit around 2003. In 2005, however, during the Tau'ri-Wraith war, the Asgard provided Earth's first Daedalus-class ship with a much more advanced form of beaming technology. However, they placed a series of fail-safes into the transporters to prevent the humans from using the technology offensively. Despite this, the Daedalus used its transporters to beam Nuclear warheads onto several Wraith Hive ships (with begrudging help from an Asgard), destroying them. The Wraith, however, were able to develop jamming codes that prevented the transporters from obtaining a lock, making the transporters all but useless against them. Shields have also proven to be just effective as jamming devices. The Korolev failed to get a clear lock as they tried to beam nuclear warheads onto Ori warships. The transporters are unable to work through either the 304's shields or the enemy ship's shields, shown when the Odyssey was only able to beam Doctor Daniel Jackson out of an Ori warship when its shields were lowered and when the Daedalus had to lower its shields to beam up Lieutenant Colonel John Sheppard and Ronon Dex. If the ship is in the middle of a battle, this is inadvisable as lowering the shields renders the 304 vulnerable for a few seconds while it uses the transporter.

Asgard computer core
The Asgard computer core is a database of all the knowledge of the Asgard. The computer core includes a knowledge base of the entire Asgard history, interactive holograms of every Asgard recorded into the knowledge base, time dilation technology, and an independent power source. These features likely only scratch the surface of the device's full capability. The Asgard gave this to the Tau'ri as a gift and to help them fight the Ori. The Asgard installed it on the Odyssey in 2007 before committing mass-suicide.

It is unknown whether the computer core was installed on any other Daedalus-class ship. Although that seems unlikely, the Phoenix had a room which contained an Asgard computer core in an alternate timeline.

Cloak
The Daedalus-class ship Odyssey acquired a very effective cloaking device of Ancient design from Dr. Daniel Jackson who, at the time, possessed the mind and Ancient knowledge of Merlin. Jackson claimed that Odyssey's Zero Point Module helped him in creating the cloak, so it's possible he utilized the ZPM on the ship in some unknown manner, or that the cloak required a level of power that only a ZPM could provide. The cloak can be activated on demand from the bridge. It must be deactivated before entering hyperspace. The Odyssey is the only BC-304 to possess this cloaking ability.

Transportation rings
In addition to the Asgard transporters, 304s also possesses transportation rings as a means of transportation. Transportation rings are used to transport people or objects over short distances, such as from ship to ship or to a nearby planet. It is unknown whether the Tau'ri utilize already-existing ring platforms or if they construct them themselves. However, the ring platforms utilized on BC-304s have a unique gray color, as opposed to the gold color seen elsewhere, possibly indicating the latter.

Heads up display
A Heads up display can be pulled up on the center window of a 304's bridge. The transparent display overlays icons on to real-world objects that can be seen through the window, such as various enemy ships and other points of interest. Much like the HUD of a Puddle Jumper, the view from the bridge remains unobstructed, meaning pilots and crew can still see the battlefield, and even weapons fire dissipating the shield before them.

Life support system
The BC-304 is equipped with a main and backup life support system. This system has the capacity to provide a breathable atmosphere for the approximately 200-member crew, in addition to a reasonably large number of passengers. Ultimately, the number of passengers the ship may transport is limited by the capacity of this system. With the system deactivated, there is enough breathable air remaining on the ship to support the crew for 9 hours, after which point the CO2 levels onboard will reach critical levels.

Computer systems
BC-304s are equipped with hundreds of individual computers with dozens of backup systems and redundancies. Many of these computers are interconnected, with several of the more-complex systems, like navigation and propulsion, requiring a certain amount of interconnectivity to properly function. Certain systems, including life support, are deliberately isolated, however, as to prevent them from being compromised by problems in other systems.

A combination of conventional Earth-based computer systems and Asgard computer systems are utilized on the BC-304, both of which are integrated together. As such, both conventional and Asgard computer terminals are present across the ship.

Subspace Capacitor (Alternate reality)
The Subspace capacitor was a power generating system created by a parallel version of the Atlantis expedition. It could reach a "near-Zero Point Module" level of energy, though it is unknown what the term 'near' exactly was. Like a ZPM, it draws energy from Subspace. Since it does not draw from a limited, contained area of subspace, but instead draws energy from our subspace time a Subspace capacitor is a renewable energy source. However, there is a limit on how much power can be stored and made available at one time.

Tractor Beam
The George Hammond possessed a tractor beam which could be used to pull smaller ships into its 302 Bays.

Engines
The 304s feature multiple means of maneuverability, notably 3 engines: Maneuvering thrusters, the Sublight drive and the Asgard hyperdrive. An alternate version of the Daedalus was equipped with a fourth drive known as the Alternate reality drive, allowing the ship to travel to alternate realities.

Maneuvering thrusters
Maneuvering thrusters are one of three methods of propulsion on 304s. While maneuvering thrusters are by far the slowest form of propulsion, they are able to make slight adjustments to a ship's trajectory and to help gain momentum. Reverse thrust is also possible, which is in place to help a ship slow down in the frictionless environment of space.

Sublight engines
The 304s have 2 main rocket boosters at the rear of the ship, which are their Sublight engines. While several smaller rocket engines also exist at the rear, these engines provide the greatest thrust, capable of moving the ship at speeds around half the speed of light.

Hyperdrive


The Tau'ri were first given Asgard hyperdrive technology as thanks for their help in fighting the Replicators, which are now standard on all 304s. However, Earth ships use considerably weaker power sources when compared to Asgard vessels, making the drives not being able to function at their true capacity. However, shortly prior to their extinction, the Asgard installed an advanced power core aboard the Odyssey. It is unclear whether this new power core actually improved the Odyssey's performance, as the ship was already using a Zero Point Module at that point. However, even under powered, these hyperdrives are one of the fastest when compared to those of most space-faring races.

Alternate reality drive (Alternate reality)
The drive was designed to transport matter through the Matter bridge to access parallel universes. It is powered by a Subspace capacitor, which provides near-Zero Point Module levels of energy. The device has to be encased in a shielded area of the ship, as it gives off radiation. Despite its ability of inter-universal travel, the ship would remain in the same relative position after every jump. The drive had a different, yet similar function as the Quantum Mirror. Dr. Rodney McKay theorized that if the drive were destroyed by C-4, it may tear a hole in the fabric of space/time large enough to destroy a solar system. It can also be implied that the drive may be somewhat sensitive when used by force, as when Dr. McKay utilized the remaining auxiliary power on the alternate Daedalus to jump sooner, which caused the drive to start "burning out".

Deceleration Thrusters
Deceleration thrusters are used to slow a 304 down. They are situated on the front side of the large rectangular hyperdrive engine sections and are mostly used to land.

Armaments
The 304 has a vast array of weapons, ranging from projectile to energy based.

Railguns
The BC-304 boasts 32 Railgun turrets for ship-to-ship combat. Just a few shots are able to take out a Wraith Dart or Goa'uld Death Glider relatively quickly. However, against capital ships, their effectiveness varies. While they have proven a match against Goa'uld Ha'tak in battle, they are far less effective against Hive ships due in part to the sheer size of such vessels and the density of their organic hulls. Furthermore, like all weapons with the exception of drone weapons and Asgard plasma beam weapons, they have proven ineffective against Ori shields.

However, against vessels that possesses shields but have them deactivated, railguns have proven quite effective at penetrating the vessels' hulls and causing serious damage. During the Battle of Asuras, an opening salvo from a 304's railguns proved powerful enough to cause severe damage to an unshielded Asuran-built Aurora-class battleship, possibly leading to its destruction.

Battle complement
Being a deep space carrier, the Daedalus-class carries a complement of several F-302 fighter-interceptors. The F-302s were originally used by the Daedalus-class' predecessor, the BC-303. The 304s can carry twice as many F-302s than the BC-303, however. It can carry two squadrons of eight F-302s, a total of sixteen fighter interceptors. The F-302s are mostly used in dogfights against other alien fighters. However, they have also proved effective in disabling the hyperdrive engines of Wraith Hive ships. The F-302s can be fitted with Nuclear warhead missiles if necessary to attack Wraith Hive ships or other ships.

Missiles
The 304s have 16 missile bays, Naquadah enhanced Nuclear warheads, and at least one ship, the Apollo, is known to have the Horizon weapon system. Among the warheads 304s are known to carry are Mark III, Mark VIII, and Mark IX. It is unknown if some of these 304s may carry conventional warheads to attack an enemy ship. However, it is also known that 304s still carry missiles as a secondary weapon in case their Asgard weapons fail.

Asgard beam weapons
Asgard plasma beam weapons were placed on the Odyssey as a gift to the Tau'ri in a mass upgrade, providing the ship with a means to effectively fight the Ori warships that had been invading the Milky Way galaxy. These weapons were eventually equipped on both the Daedalus and the Apollo, which put them to good use almost immediately when they used them to rapidly destroy the Aurora-class battleships that the Asurans were deploying in the Pegasus galaxy. In an alternate timeline, these weapons were also equipped to the Phoenix, and used to destroy Wraith Hive ships in even fewer hits than Ori warships and Aurora-class warships, as Hive ships possess no shields (allowing even easier penetration). It is more than likely that these weapons will be installed on all other 304s as well. The beam weapons can penetrate the shields of the Ori, Asuran, and probably the Lucian Alliance Warships.

Horizon Weapons system
The system consists of a large, bullet-shaped delivery module containing ten missiles, six with Mark IX tactical warheads and four decoys. The device can be carried in the bomb bay of a 304 like the Apollo. Deployed from orbit, the module's three rocket engines propel it into the atmosphere; these rockets shut down and the missiles themselves are released about twelve seconds prior to impact, finding individual targets and detonating simultaneously. The total time from launch to detonation is about one minute. It is unknown if the other 304's have this weapon system and a bomb bay.

Known 304s

 * USS Daedalus -Fast Attack Wing – Colonel Steven Caldwell
 * USS Odyssey – Colonel Ian Davidson
 * RFS Korolev (destroyed) – Colonel Chekov
 * USS Apollo - Second Tactical Wing – Colonel Abraham Ellis
 * Sun Tzu - Lt. Colonel Yin, Chinese crew
 * USS George Hammond - Second Tactical Wing - formerly the USS Phoenix (destroyed in an alternate timeline) – Colonel Samantha Carter

Bridge Location
The Bridge of the 304s is occasionally identified by fans and the MGM Tech Journal as being on the structure towards the ship's rear. However, it is often identified on the show as residing in the structure at the beginning of the ship's neck. This contradiction is likely due to the ship's neck only sporadically being shown through the bridge's main viewport (as it clearly is in the episodes "Allies" and "Air, Part 1"). Scenes in which the neck does not appear outside the bridge's window could potentially be attributed to the angle at which the scene was shot, or possibly because it was left out by the producers for whatever reason. However, as there is more evidence to show that the bridge is in the structure atop the ship's neck, this article describes the bridge as being at that location.
 * There could be another explanation for this. In "Unending" and Stargate: The Ark of Truth, there are scenes which seem to depict the bridge as being located on the rear superstructure. It might be possible that not all 304s have their bridge in the same location; The bridge of the Daedalus and George Hammond could be found at the neck structure, while other 304s have their bridges at the rear, for reasons as of yet unknown. It is also be possible, though unlikely, that 304s have bridges in both location.
 * In the episode "Unending" at around 31:20, there is a scene where Col. Mitchell looks out a window that has the same design as the window at the front of the bridge. However, as we never actually see the back of the room he's in, it is unknown whether or not he is actually standing in the bridge. It may just be a room atop the ship's rear structure with a similar window.
 * The MGM tech journal identifies an incorrect location for the bridge of Aurora-class battleships, which calls into question the accuracy of that source.

Bridge Terminal
In the episodes The Siege, Part 3 and The Intruder, the leftmost wall of the Daedalus contained an illuminated static panel that displayed a schematic-like diagram of a ship resembling a BC-303 class vessel. Starting with the episode Aurora, this panel was replaced with a large computer display, which filled the entire space previously occupied by the illuminated panel. Starting with the episode No Man's Land of Stargate Atlantis (and Flesh and Blood of Stargate SG-1, both of which originally aired together) this large display was replaced with a slightly smaller display, which is slightly recessed into the wall. Starting with the episode The Daedalus Variations, a computer console was placed in front of this display.

Bridge Plaque
On the bridge of each BC-304 is a plaque denoting the name of the ship, its class, and to what wing it is assigned. This plaque first made an appearance in Season 4 of Stargate Atlantis on the Apollo, taking the place of an illuminated panel that previously appeared in the same location on all BC-304s in all preceding episodes. This plaque was possibly added as a way to more-clearly distinguish each BC-304 as more BC-304s began being introduced in the series.

Miscellaneous

 * On various occasions, notably in "Moebius, Part 1" and "The Siege, Part 3", the design of the 304 is shown to be that of a hybrid of a Prometheus-like design with front components similar to that of the finalized 304 design. Although as time progressed, these sightings have disappeared. They do appear on occasion, such as on the Korolev in "Camelot".
 * On various occasions, the tower towards the rear of the ship appears on the ship's right side instead of left. This is the case with the Odyssey in "The Pegasus Project" and the Apollo in certain parts of "Be All My Sins Remember'd". However, they appear like this sporadically throughout the series.
 * On the MGM Tech Journal entry for the 304, an Asgard beam turret is labeled as being at a location on the end of the neck. However, the object labeled as the beam turret existed before the Asgard upgrades.
 * The MGM Tech Journal omits a Satellite dish-like array on the rear structure above the location it labels as the 'bridge'.
 * While the Daedalus, Odyssey and George Hammond are shown to serve the role of a battlecruiser and support ship for the SGC and Atlantis, the Apollo appears to mainly serve in the form of performing special missions. Two of its known missions were to launch Horizon upon Asuras to stop a potential attack on Earth and to assist in hunting Poole's Replicator on Earth. The other missions shown for the ship are to defend Earth when no other ship is available in Stargate: The Ark of Truth, a mission in "Be All My Sins Remember'd" that required both the Apollo and the Daedalus and a single routine mission to Atlantis in "Remnants". Aside from that single routine mission, the Apollo is only ever seen serving during special circumstances. In contrast, the Odyssey, the Daedalus and the George Hammond are regularly seen being sent on more routine missions such as support to SG teams and Atlantis.
 * An alternate version of the Daedalus in The Daedalus Variations had an orange map display on the bridge, rather than the green one present in the main universe. Additionally, in The Last Man, an alternate version of the George Hammond had an Asgard terminal in order to give the crew access to the Asgard Core while on the bridge.