User:WDGraham/List of unflown orbital launch systems

Throughout the history of spaceflight many orbital launch systems have been proposed, designed and entered development, only to be cancelled before development was completed, without making any orbital launch attempts. Some launch systems were concept designs or studies, or proposals which were never taken further, whilst others such as the Ares I reached the stage of hardware construction and partial flight tests before cancellation.

This list contains orbital launch systems which were cancelled before making an orbital launch attempt. It includes rockets which made atmospheric and suborbital tests prior to cancellation, such as Ares I, however it does not include rockets cancelled after failed orbital launch attempts, such as the N1, Europa and Pilot.

A

 * Ares I - 🇺🇸. NASA design to launch Orion as part of Project Constellation, first stage to have been built by ATK, second by Boeing. Capable of placing 25.6 t of payload into low Earth orbit. Designed by Exploration Systems Architecture Study in 2005, cancelled in 2010 along with Constellation programme
 * Ares IV - 🇺🇸. Proposed alternative to Ares I using the same first stage as Ares V. Capable of placing 40 t to TLI.
 * Ares V - 🇺🇸. NASA design to launch Altair and Earth Departure Stage as part of Project Constellation, boosters to have been built by ATK. Capable of placing 160 to 188 t into low Earth orbit and 63 to 71 t to TLI. Designed by Exploration Systems Architecture Study in 2005, cancelled in 2010 along with Constellation programme
 * Ares V Lite - 🇺🇸. Proposed unified launch system for Project Constellation, combining the roles of the Ares I and Ares V into two launches of a single vehicle. Payload of 140 t to Low Earth Orbit.

F

 * Falcon 5 - 🇺🇸. SpaceX rocket with five first stage engines but otherwise identical to the Falcon 9. Cancelled in 2007
 * Falcon 9S5 - 🇺🇸. SpaceX rocket consisting of a Falcon 9 with two Falcon 5 first stages being used as boosters. Cancelled along with Falcon 5 in 2007
 * Falcon X - 🇺🇸. SpaceX concept design capable of delivering 38 t into low Earth orbit. Heavy configuration capable of 125 t to LEO.
 * Falcon XX - 🇺🇸. SpaceX concept design capable of delivering 140 t into low Earth orbit.

J

 * Jupiter - 🇺🇸. Designed in 2006 as part of the DIRECT programme, an unofficial NASA design study which proposed alternatives to the Ares family of rockets for Project Constellation (started in 2006) to replace Space Shuttle. Many variants were proposed, such as the Jupiter-130 and Jupiter-246, with claimed lift capacities exceeding 60 and 90 t to LEO respectively; increasing to 100 t with an upper stage, and 120 t with five-segment solid rocket boosters as well.

M

 * Magnum - 🇺🇸. Designed by NASA between 1996 and 2004, Magnum was intended to launch a manned mission to Mars, with a payload capacity of 55 to 94 t to Low Earth orbit, with 80 t. The rocket never made it past the preliminary design phase.
 * MLV-SDV-1a: 55 t of payload to a 407 km circular low Earth orbit inclined at 28.5 degrees. Two reusable RSRM boosters on first stage.
 * MLV-SDV-1b: 94 t of payload to a 407 km circular low Earth orbit inclined at 28.5 degrees. Four reusable RSRM boosters on first stage, core stage air-lit 100 seconds after launch.
 * MLV-SDV-2: 80 t of payload to a 407 km circular low Earth orbit inclined at 28.5 degrees. First stage augmented by two reusable RSRM boosters and two liquid fuelled boosters each powered by two SSMEs.
 * MLV-SDV-3: 91 t of payload to a 407 km circular low Earth orbit inclined at 28.5 degrees. First stage augmented by two liquid-fuelled boosters each powered by three RD-180 engines.
 * MLV-SDV-4: 64 t of payload to a 407 km circular low Earth orbit inclined at 28.5 degrees. First stage augmented by two liquid-fuelled boosters each powered by four unspecified engines burning RP-1 and liquid oxygen.
 * MLV-LFBB: 93 t of payload to a 407 km circular low Earth orbit inclined at 28.5 degrees. First stage augmented by two reusable fly-back boosters powered by RD-180 engines.

N

 * N1-MOK - . Cryogenically-fuelled single-stage to orbit rocket based on the N1 first stage. Proposed in 1974, it would have had a payload capacity of 90 t into a circular low Earth orbit at an altitude of 450 km and an inclination of 97.5 degrees.
 * N1 Nuclear A - . A variant of the N1 studied by Sergei Korolev in 1963, the N1 Nuclear A would have used a third stage powered by a nuclear thermal engine, and been capable of placing 270 t of payload into a circular low Earth orbit at an altitude of 220 km, and an inclination of 51.6 degrees.
 * N1 Nuclear AF - . Derivative of the proposed N1 Nuclear A, which would have used less efficient engines delivering higher thrust, and could have placed 300 t of payload into a circular low Earth orbit at an altitude of 220 km, and an inclination of 51.6 degrees.
 * N1 Nuclear V - . Derivative of the N1 rocket with nuclear-powered second and third stages, capable of placing 420 t of payload into a circular low Earth orbit at an altitude of 220 km, and an inclination of 51.6 degrees.
 * N1 Nuclear V-B - . A variant of the N1 Nuclear V, the N1 Nuclear V-B would have had additional radiation shielding, allowing it to launch manned spacecraft. It could have placed 360 t into a circular low Earth orbit at an altitude of 220 km, and an inclination of 51.6 degrees.
 * N1F - . An N1 derivative with upgraded engines, larger second and third stages, and incorporating changes made as a result of the four launch failures between 1969 and 1972. The 1965 design would have been capable of placing 100 t of payload into a circular low Earth orbit at an altitude of 220 km and an inclination of 51.6 degrees. By the time development was cancelled in 1975, this had increased to 105 t. Use of Blok S and Block R upper stages was also considered for launching L3M lunar missions.
 * N1FV-II-III: Proposed variant with cryogenic second and third stages capable of placing 150 t into a circular low Earth orbit at an altitude of 220 km and an inclination of 51.6 degrees.
 * N1FV-III: Proposed variant with Blok V-III third stage, capable of placing 125 t into a circular low Earth orbit at an altitude of 220 km and an inclination of 51.6 degrees.
 * N1F/Sr: A derivative of the N1F, with a Blok Sr cryogenic upper stage in place of the N1F's Blok G and Blok D fourth and fifth stages.


 * N1M - . Designed in 1965 as the heaviest N1 derivative, with the payload capacity of the first stage doubled. It would have been capable of placing 155 t into a circular low Earth orbit at an altitude of 220 km, and an inclination of 51.6 degrees, subsequently redesigned a standard first stage and cryogenic upper stages to launch the LEK spacecraft on missions to the Moon. Development abandoned in 1971.
 * N1MV-II-III: Proposed variant using cryogenic second and third stages to deliver a payload of 230 t to a circular low Earth orbit at an altitude of 220 km and an inclination of 51.6 degrees.
 * N1MV-III: Proposed variant with Blok V-III third stage, capable of placing 185 t into a circular low Earth orbit at an altitude of 220 km and an inclination of 51.6 degrees.


 * N1U - . Proposed production version of the N1 with improvements to increase reliability, particularly its engines. Capable of placing 95 t into a circular low Earth orbit at an altitude of 220 km and an inclination of 51.6 degrees.
 * N1UV-III: Derivative with Blok V-III third stage, capable of placing 115 t into a circular low Earth orbit at an altitude of 220 km and an inclination of 51.6 degrees.
 * Nova - 🇺🇸. Family of super-heavy launch systems studied by NASA for manned missions beyond Earth orbit. Some Nova-rockets, including the Nova C-8 and Nova 8L, were intended for direct ascent lunar missions, which were cancelled in favour of lunar orbit rendezvous with the Saturn V rocket. These rockets had a payload capacity of 24 to 75 t tons to TLI, compared to the Saturn V's capacity of 45 t. Larger variants designed for missions to Mars could have placed up to 455 t into Low Earth orbit.

S

 * Saturn V/4-260 - 🇺🇸. Late 1960s Saturn V derivative studied by Boeing; using four 6.6 m diameter solid rocket motors, which would also have incorporated liquid propellant tanks for the first stage. Capable of placing 362 t of payload into a circular low Earth orbit at an altitude of 426 km and an inclination of 28 degrees.
 * Saturn V-23(L) - 🇺🇸. Saturn V derivative studied in 1967 by Boeing, with stretched first and third stages, and four liquid fuelled boosters, each powered by two F-1 engines. Capable of placing 262.67 t into a circular low Earth orbit at an altitude of 185 km and an inclination of 28 degrees.
 * Saturn V-24(L) - 🇺🇸. Saturn V derivative studied in 1967 by Boeing, with all three stages stretched, first stage engines replaced with F-1As and second and third stage engines replaced with HG-3s. Augmented by four F-1A-powered liquid boosters. Capable of delivering 435.3 t of payload into a circular low Earth orbit at an altitude of 185 km and an inclination of 28 degrees.
 * Saturn V-25(S)B - 🇺🇸. Saturn V derivative studied in 1967 by Boeing, with stretched first and third stages, and four 3.96 m solid rocket motors. Capable of placing 223.5 t into a circular low Earth orbit at an altitude of 185 km and an inclination of 28 degrees.
 * Saturn V-4X(U): A derivative using four clustered first and second stages to give a payload capacity of 527 t to
 * Saturn V-25(S)U: Derivative with NERVA nuclear-powered third stage, intended for assembling spacecraft in Earth orbit capable of sending men to Mars. Payload capacity of 248.663 t to a circular low Earth orbit at an altitude of 426 km and an inclination of 28 degrees, or 160 t to TLI.


 * Sea Dragon - 🇺🇸. A two-stage reusable sea-launched rocket studied in 1962, which would have been capable of placing 550 t into LEO.
 * SERV - 🇺🇸. Designed by Chrysler as their proposal for the Space Transportation System in the 1970s, SERV would have used the existing Saturn V launch complex, and could be used to launch the MURP spaceplane. It was capable of placing 11 to 57 t into low Earth orbit, depending on the configuration, and whether MURP was being carried.
 * Shuttle-C - 🇺🇸. Proposed Shuttle-Derived Launch Vehicle which would have used then-existing Shuttle-components and infrastructure to place an unmanned payload of 60 to 80 t into orbit. The configuration consisted of a Space Shuttle external tank and set of solid rocket boosters, but with an SSME-powered unmanned cargo vehicle in place of the orbiter.
 * Shuttle-Derived Heavy Lift Launch Vehicle - 🇺🇸. Shuttle-Derived Launch Vehicle proposed as an alternative launch system for Project Constellation, capable of placing up to 104 t of cargo into low Earth orbit. Other configurations would have been able to place 66 to 83 t into LEO.
 * Superraket - . 1950s study of a rocket incorporating a nuclear-powered second stage. Capable of placing 150 t into low Earth orbit at an altitude of 185 km.

U

 * UR-700 - . Designed by Vladimir Chelomey in the 1960s, the UR-700 was based on the UR-500 rocket and designed for manned lunar missions using the direct ascent method. The N1 was developed instead, using the lunar orbit rendezvous method. UR-700 development continued until 1968 with different variants considered, with payloads between 70 and 175 t to LEO (151 t for the original design). Using an 11D54 upper stage, it would have been able to deliver 185 t to a circular low Earth orbit at 200 km altitude and 51.5° inclination. Using an upper stage powered by three RD-350 engines this could have been increased to 215 t to an orbit at 200 km and 51.0° inclination, With an upper stage powered by seven RO-31 engines it could have placed 230 to 270 t into low Earth orbit.
 * UR-700M - . Designed by Vladimir Chelomey in 1969 for Project Aelita, a Soviet programme to land a man on Mars in 1969. The design was based on the UR-700 rocket, and had a payload capacity of 750 t to a circular low Earth orbit at 200 km altitude and 51.0° inclination.
 * UR-900 - . Derivative of the UR-700 designed by Vladimir Chelomey, and proposed in 1969 for manned missions to Mars. Payload capacity of 240 t to a circular low Earth orbit at 200 km altitude and 51.0° inclination. Cancelled after a Proton launch failure raised concerns over the safety of its hypergolic propellants

V

 * Vulkan-Herkules - . Energia derivative capable of placing 200 t of payload into low Earth orbit.

Unsorted

 * Saturn V-A, a NASA-study in 1968 essentially identical to Saturn INT-20. Payload to LEO 60,000 kg.
 * Saturn V-C, a NASA-study in 1968 extending the Saturn V-A and Saturn INT-20-studies. Payload to LEO 81,600 kg.
 * Saturn V-Centaur, another NASA-study in 1968 extending the Saturn V-A and Saturn INT-20-studies. Payload to LEO 118,000 kg.
 * Saturn V-D, a NASA-study of 1968 extending the Boeing-study of 1967 to develop a Saturn V-based rocket. Payload to LEO 326,500 kg.
 * Saturn V ELV, a NASA study of 1966 to develop Saturn V-based rocket. Payload to LEO 200,000 kg.
 * Saturn C-3B, a launcher studied in the USA in 1961. Cancelled after the Saturn C-5 was selected for Apollo program(Saturn C-5-rocket later evolved into Saturn V). Would have had the payload capacity of 78,000 kg to LEO.
 * Saturn C-3BN, a launcher studied in the USA in 1961. Cancelled after the Saturn C-5 was selected for Apollo program; the Saturn V-rocket was based in the Saturn C-5. Otherwise similar to Saturn C-3B, but would have utilized a nuclear upper stage. Payload capacity of 94,000 kg to LEO.
 * Saturn C-4, an American launch vehicle studied for the lunar orbit rendezvous-method of lunar exploration. Lost competition for the launcher of the Apollo program to Saturn C-5 (Saturn C-5 was modified slightly during the 1960s to produce the Saturn V-rocket) because Saturn C-5 had reserve capacity that the Moon mission designers wanted. Payload to LEO 99,000 kg.
 * Saturn C-4B, the last variant of Saturn C-4 before Saturn C-5 was chosen for the Moon landing in 1961 (Saturn C-5 was modified slightly during the 1960s to produce the Saturn V-rocket) and the development of other Saturn C-series rockets was halted. Payload 95,000 kg to LEO.
 * Saturn C-5, the rocket that was chosen for the Apollo program in 1961. Saturn C-5's development was continued after it was chosen to be the American Moon rocket, and the result was Saturn V. The difference between Saturn C-5 and Saturn V (albeit small) is that the upper stages of Saturn V were enlarged in relation to the C-5. The Saturn C-5-configuration of 1961 had payload capacity to LEO 120,000 kg.
 * Saturn C-5N, was a conceptual version of the Saturn V launch vehicle which would have had a nuclear third stage. Payload to LEO 155,000 kg.
 * Saturn C-8, the largest of Saturn-variants to be considered. Was intended for direct landing method of lunar exploration, like the Nova's. Was abandoned after the Saturn C-5 was selected for Apollo program(Saturn C-5 developed into the Saturn V). Payload to LEO 210 ton.
 * Saturn INT-18, a conceptual study in 1966 to build a rocket utilizing various Saturn V-components. Numerous version were studied, with payload capacity between 21,300 - 66,590 kg to LEO (two heaviest variant had payload capacities of 51,700 kg and 66,400-66,590 kg to LEO.)
 * Saturn INT-20, a proposed launcher in the 1960s-1970s using the Saturn V-components. Three variants were studied with the heaviest (the five-engine variant) having payload capacity of 60,500 kg to LEO, and the second heaviest (the four-engine variant) having payload capacity of 60,000 kg to LEO.
 * Saturn INT-21, described in a study of the 1970s to develop a smaller launcher based on Saturn V. It was expected to be composed of Boeing S-IC and modified North American S-II with payload capacity of 75,000 kg to LEO. Also heavier variants with payload to LEO 84,000 kg, 89,000 kg, 101,000 kg, 112,000 kg and 116,000 kg were studied (the heavier variants had successively more engines).
 * Saturn MLV-V-1, a NASA-study of an improved Saturn V-rocket in 1965. Payload to LEO 137,250 kg.
 * Saturn MLV-V-1A, a NASA-study of an improved Saturn V-rocket in 1965. Payload to LEO 145,000 kg.
 * Saturn MLV-V-2, a NASA-study to develop the Saturn V-rocket in 1965. Payload to LEO 137,250 kg
 * Saturn MLV-V-3, a NASA-study in 1965 to improve the Saturn V. Payload to LEO 160,400 kg
 * Saturn V-3B, a Boeing-studied variation of a Saturn MLV-V-3-study. Studied in 1967. Rocket was based in the Saturn V-rocket. Payload capacity 166,600 kg to LEO.


 * Saturn MLV-V-4(S), rocket NASA studied in 1965. A developed version of Saturn V. Payload 118,000 kg to LEO.
 * Saturn MLV-V-4(S)-A, a development of the Saturn V studied by NASA in 1965. Payload to LEO 160,880 kg.
 * Saturn MLV-V-4(S)-B, a rocket studied by Boeing in 1967. Was based on Saturn V. Payload to LEO 171,990 kg.