An expendable launch system is a launch vehicle that can be launched only once, after which its components are either destroyed during reentry or discarded in space. ELVs typically consist of several rocket stages that are discarded sequentially as their fuel is exhausted and the vehicle gains altitude and speed. As of 2022, most satellites and human spacecraft are currently launched on ELVs. ELVs are simpler in design than reusable launch systems and therefore may have a lower production cost. Furthermore, an ELV can use its entire fuel supply to accelerate its payload, offering greater payloads. ELVs are proven technology in widespread use for many decades.
The Centaur is a family of rocket propelled upper stages produced by U.S. launch service provider United Launch Alliance, with one main active version and one version under development. The 3.05 m (10.0 ft) diameter Common Centaur/Centaur III flies as the upper stage of the Atlas V launch vehicle, and the 5.4 m (18 ft) diameter Centaur V is being developed as the upper stage of ULA's new Vulcan rocket. Centaur was the first rocket stage to use liquid hydrogen (LH2) and liquid oxygen (LOX) propellants, a high-energy combination that is ideal for upper stages but has significant handling difficulties.
The RM-81 Agena was an American rocket upper stage and satellite bus which was developed by Lockheed Corporation initially for the canceled WS-117L reconnaissance satellite program. Following the split-up of WS-117L into SAMOS and Corona for image intelligence, and MIDAS for early warning, the Agena was later used as an upper stage, and an integrated component, for several programs, including Corona reconnaissance satellites and the Agena Target Vehicle used to demonstrate rendezvous and docking during Project Gemini. It was used as an upper stage on the Atlas, Thor, Thorad and Titan IIIB rockets, and considered for others including the Space Shuttle and Atlas V. A total of 365 Agena rockets were launched between February 28, 1959 and February 1987. Only 33 Agenas carried NASA payloads and the vast majority were for DoD programs.
The Agena Target Vehicle, also known as Gemini-Agena Target Vehicle (GATV), was an uncrewed spacecraft used by NASA during its Gemini program to develop and practice orbital space rendezvous and docking techniques, and to perform large orbital changes, in preparation for the Apollo program lunar missions. The spacecraft was based on Lockheed Aircraft's Agena-D upper stage rocket, fitted with a docking target manufactured by McDonnell Aircraft. The name 'Agena' derived from the star Beta Centauri, also known as Agena. The combined spacecraft was a 26-foot (7.92 m)-long cylinder with a diameter of 5 feet (1.52 m), placed into low Earth orbit with the Atlas-Agena launch vehicle. It carried about 14,021 to 14,054 pounds of propellant and gas at launch, and had a gross mass at orbital insertion of 7,117 to 7,271 pounds.
Titan IIIB was the collective name for a number of derivatives of the Titan II ICBM and Titan III launch vehicle, modified by the addition of an Agena upper stage. It consisted of four separate rockets. The Titan 23B was a basic Titan II with an Agena upper stage, and the Titan 24B was the same concept, but using the slightly enlarged Titan IIIM rocket as the base. The Titan 33B was a Titan 23B with the Agena enclosed in an enlarged fairing, in order to allow larger payloads to be launched. The final member of the Titan IIIB family was the Titan 34B which was a Titan 24B with the larger fairing used on the Titan 33B.
The Titan IIIC was an expendable launch system used by the United States Air Force from 1965 until 1982. It was the first Titan booster to feature large solid rocket motors and was planned to be used as a launcher for the Dyna-Soar, though the spaceplane was cancelled before it could fly. The majority of the launcher's payloads were DoD satellites, for military communications and early warning, though one flight (ATS-6) was performed by NASA. The Titan IIIC was launched exclusively from Cape Canaveral while its sibling, the Titan IIID, was launched only from Vandenberg AFB.
Atlas II was a member of the Atlas family of launch vehicles, which evolved from the successful Atlas missile program of the 1950s. The Atlas II was a direct evolution of the Atlas I, featuring longer first stage tanks, higher-performing engines, and the option for strap-on solid rocket boosters. It was designed to launch payloads into low Earth orbit, geosynchronous transfer orbit or geosynchronous orbit. Sixty-three launches of the Atlas II, IIA and IIAS models were carried out between 1991 and 2004; all sixty-three launches were successes, making the Atlas II a highly reliable space launch system. The Atlas line was continued by the Atlas III, used between 2000 and 2005, and the Atlas V which is still in use.
The Scout family of rockets were American launch vehicles designed to place small satellites into orbit around the Earth. The Scout multistage rocket was the first orbital launch vehicle to be entirely composed of solid fuel stages. It was also the only vehicle of that type until the successful launch of the Japanese Lambda 4S in 1970.
The Atlas-Centaur was a United States expendable launch vehicle derived from the SM-65 Atlas D missile. The vehicle featured a Centaur upper stage, the first such stage to use high-performance liquid hydrogen as fuel. Launches were conducted from Launch Complex 36 at the Cape Canaveral Air Force Station (CCAFS) in Florida. After a strenuous flight test program, Atlas-Centaur went on to launch several crucial spaceflight missions for the United States, including Surveyor 1, Mariner 4, and Pioneer 10/11. The vehicle would be continuously developed and improved into the 1990s, with the last direct descendant being the highly successful Atlas II.
In aerospace engineering, spin stabilization is a method of stabilizing a satellite or launch vehicle by means of spin, i.e. rotation along the longitudinal axis. The concept originates from conservation of angular momentum as applied to ballistics, where the spin is commonly obtained by means of rifling. For most satellite applications this approach has been superseded by three-axis stabilization.
The Atlas III was an American orbital launch vehicle, used in the years between 2000 and 2005. It was developed from the highly successful Atlas II rocket and shared many components. It was the first member of the Atlas family since the Atlas A to feature a "normal" staging method, compared to the previous Atlas family members, which were equipped with two jettisonable outboard engines on the first (booster) stage. The Atlas III was developed further to create the Atlas V, which still flies to this day.
The Inertial Upper Stage (IUS), originally designated the Interim Upper Stage, was a two-stage, solid-fueled space launch system developed by Boeing for the United States Air Force beginning in 1976 for raising payloads from low Earth orbit to higher orbits or interplanetary trajectories following launch aboard a Titan 34D or Titan IV rocket as its upper stage, or from the payload bay of the Space Shuttle as a space tug.
The Atlas-Agena was an American expendable launch system derived from the SM-65 Atlas missile. It was a member of the Atlas family of rockets, and was launched 109 times between 1960 and 1978. It was used to launch the first five Mariner uncrewed probes to the planets Venus and Mars, and the Ranger and Lunar Orbiter uncrewed probes to the Moon. The upper stage was also used as an uncrewed orbital target vehicle for the Gemini crewed spacecraft to practice rendezvous and docking. However, the launch vehicle family was originally developed for the Air Force and most of its launches were classified DoD payloads.
Atlas is a family of US missiles and space launch vehicles that originated with the SM-65 Atlas. The Atlas intercontinental ballistic missile (ICBM) program was initiated in the late 1950s under the Convair Division of General Dynamics. Atlas was a liquid propellant rocket burning RP-1 kerosene fuel with liquid oxygen in three engines configured in an unusual "stage-and-a-half" or "parallel staging" design: two outboard booster engines were jettisoned along with supporting structures during ascent, while the center sustainer engine, propellant tanks and other structural elements remained connected through propellant depletion and engine shutdown.
Thor was a US space launch vehicle derived from the PGM-17 Thor intermediate-range ballistic missile. The Thor rocket was the first member of the Delta rocket family of space launch vehicles. The last launch of a direct derivative of the Thor missile occurred in 2018 as the first stage of the final Delta II.
The Atlas I was a US expendable launch system manufactured by General Dynamics in the 1990s to launch a variety of satellites. It was largely a commercial rebrand of the Atlas G, but did feature several electrical and guidance improvements. Atlas I did not feature any major payload capacity improvements over its predecessor but did offer a larger payload fairing option. Eleven launches took place, with three failures.
This comparison of orbital launch systems lists the attributes of all individual rocket configurations designed to reach orbit. A first list contains rockets that are operational or in development as of 2023; a second list includes all upcoming rockets and a third list includes all retired rockets For the simple list of all conventional launcher families, see: Comparison of orbital launchers families. For the list of predominantly solid-fueled orbital launch systems, see: Comparison of solid-fueled orbital launch systems.
The Atlas E/F was an American expendable launch system and sounding rocket built using parts of decommissioned SM-65 Atlas missiles. It was a member of the Atlas family of rockets.
The Titan IIIE or Titan 3E, also known as the Titan III-Centaur, was an American expendable launch system. Launched seven times between 1974 and 1977, it enabled several high-profile NASA missions, including the Voyager and Viking planetary probes and the joint West Germany-U.S. Helios spacecraft. All seven launches were conducted from Cape Canaveral Air Force Station Launch Complex 41 in Cape Canaveral, Florida.
The Atlas G, also known as Atlas G Centaur-D1AR was an American expendable launch system derived from the Atlas-Centaur. It was a member of the Atlas family of rockets and was used to launch seven communication satellites during the mid to late 1980s. Atlas G consisted of an improved Atlas core with modernized avionics and stretched propellant tanks. The Centaur stage also had several updated components and other technical improvements. Atlas G flew 7 times, with all missions aiming to go to a geostationary transfer orbit. It was replaced by the near-identical Atlas I, which had an improved guidance system and offered a larger payload fairing.
ATDA launch, Atlas SLV-3, June 1, 1966
PRIME launch, Atlas SLV-3 rocket with a Burner II upper stage, August 16, 1968.
Mariner 7 launch, Atlas SLV-3C.
Surveyor 6 launch, Atlas-Centaur (AC-14)
Mariner 9 launch, Atlas-Centaur
Mariner 10 launch, Atlas SLV-3D Centaur-D1A
Pioneer 11 launch, Atlas-Centaur 30
