A modular rocket is a kind of multistage rocket which has components that can interchanged for different missions. Several such rockets use similar concepts such as unified modules to minimize expenses on manufacturing, transportation and for optimization of support infrastructure for flight preparations.
The National Launch System study (1991-1992) looked at future launchers in a modular (cluster) fashion. This concept has existed since the creation of NASA.
A government commission, the "Saturn Vehicle Evaluation Committee" (better known as the Silverstein Committee), assembled in 1959 to recommend specific directions that NASA could take with the existing Army rocket program (Jupiter, Redstone, Sergeant). NASA's Space Exploration Program Council (1959-1963) was tasked with developing the launch architecture for the new Saturn rocket series, called Saturn C. The Saturn C architecture consisted of five different stages (S-I, S-II, S-III, S-IV, and S-V/Centaur) that could be stacked vertically for specific rockets to meet various NASA payload and mission requirements.
This work led to development of the Saturn I, Saturn IB, and Saturn V rockets.
The Atlas V expendable launch system uses the liquid fueled Common Core Booster as its first stage. In most configurations a single CCB is used with strap-on solid rocket boosters. A proposed configuration for heavier loads strapped together three CCBs for the first stage. The Common Core Booster utilizes the Russian made RD-180 burning RP-1 fuel with liquid oxygen producing a thrust of 3.8 MN. The liquid propellant tanks use an isogrid design for strength, replacing previous Atlas tank designs which were pressure stabilized. [1]
The length of the common core booster is 89 feet (27 m), and has a diameter of 12.5 feet (3.8 m). [2]
The Delta IV launcher family used the liquid fuel Common Booster Core as the first stage of the various rocket configurations. One or three modules could be used as the first stage. In most configurations a single CBC is used with or without strap-on SRBs. Three CBCs together formed the first stage of the Heavy configuration. The CBC used the Rocketdyne RS-68 engine and burned liquid hydrogen with liquid oxygen producing a thrust of 2.9 meganewtons (650,000 lbf).[ citation needed ]
The Universal Rocket Module (URM) is the modular liquid fueled first stage of the Angara expendable launch system. Depending on the configuration, the first stage can consist of 1, 3, 5 or 8 URMs. Each URM uses a Russian-made RD-191 engine burning RP-1 fuel with liquid oxygen producing a thrust of 1.92 MN. [3]
The Falcon Heavy launch vehicle consists of a strengthened Falcon 9 Block 5 center core with two regular Falcon 9 Block 5 core stages with aerodynamic nosecones mounted on top of both acting as liquid-fuel strap-on boosters. Each core is powered by nine Merlin 1D engines burning rocket-grade kerosene fuel with liquid oxygen producing almost 7.7 meganewtons (1,700,000 lbf) of thrust, and all three cores together producing over 22MN of thrust. A first design of the Falcon Heavy included a unique propellant crossfeed capability, where fuel and oxidizer to power most of the engines on the center core would be fed from the two side cores, up until the side cores would be near empty and ready for the first separation event. [4] However, due to its extreme complexity this feature was cancelled in 2015 leaving each of the three cores to burn its own fuel. Later evaluations revealed that the propellant needed for each side booster to land (reuse) are already close to the margins so there is really no advantage to crossfeed.
Like the single stick Falcon 9, each Falcon Heavy booster core is reusable. [5] The Falcon Heavy Test Flight demonstrated the two side boosters landing simultaneously near their launch site, while the central booster attempted a landing on SpaceX's Autonomous spaceport drone ship, which resulted in a hard landing near the ship. During the second mission all three boosters landed softly. [6] A Falcon Heavy launch that succeeds in recovering all three core boosters has the same material expenditure as the Falcon 9, i.e. the upper stage and potentially the payload fairing. As such, the difference in cost between a Falcon 9 and a Falcon Heavy launch is limited, mainly to the extra fuel and refurbishing three as opposed to one booster core.
Energia was a 1980s super-heavy lift launch vehicle. It was designed by NPO Energia of the Soviet Union as part of the Buran program for a variety of payloads including the Buran spacecraft. Control system main developer enterprise was the Khartron NPO "Electropribor". The Energia used four strap-on boosters each powered by a four-chamber RD-170 engine burning kerosene/LOX, and a central core stage with four single-chamber RD-0120 (11D122) engines fueled by liquid hydrogen/LOX.
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 2024, less and less satellites and human spacecraft are launched on ELVs in favor of reusable launch vehicles. However, there are many instances where a ELV may still have a compelling use case over a reusable vehicle. 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.
Proton is an expendable launch system used for both commercial and Russian government space launches. The first Proton rocket was launched in 1965. Modern versions of the launch system are still in use as of 2023, making it one of the most successful heavy boosters in the history of spaceflight. The components of all Protons are manufactured in the Khrunichev State Research and Production Space Center factory in Moscow and Chemical Automatics Design Bureau in Voronezh, then transported to the Baikonur Cosmodrome, where they are assembled at Site 91 to form the launch vehicle. Following payload integration, the rocket is then brought to the launch pad horizontally by rail, and raised into vertical position for launch.
Delta IV was a group of five expendable launch systems in the Delta rocket family introduced in the early 2000s. Originally designed by Boeing's Defense, Space and Security division for the Evolved Expendable Launch Vehicle (EELV) program, the Delta IV became a United Launch Alliance (ULA) product in 2006. The Delta IV was primarily a launch vehicle for United States Air Force (USAF) military payloads, but was also used to launch a number of United States government non-military payloads and a single commercial satellite.
The Saturn I was a rocket designed as the United States' first medium lift launch vehicle for up to 20,000-pound (9,100 kg) low Earth orbit payloads. The rocket's first stage was built as a cluster of propellant tanks engineered from older rocket tank designs, leading critics to jokingly refer to it as "Cluster's Last Stand". Its development was taken over from the Advanced Research Projects Agency in 1958 by the newly formed civilian NASA. Its design proved sound and flexible. It was successful in initiating the development of liquid hydrogen-fueled rocket propulsion, launching the Pegasus satellites, and flight verification of the Apollo command and service module launch phase aerodynamics. Ten Saturn I rockets were flown before it was replaced by the heavy lift derivative Saturn IB, which used a larger, higher total impulse second stage and an improved guidance and control system. It also led the way to development of the super-heavy lift Saturn V which carried the first men to landings on the Moon in the Apollo program.
The Space Shuttle external tank (ET) was the component of the Space Shuttle launch vehicle that contained the liquid hydrogen fuel and liquid oxygen oxidizer. During lift-off and ascent it supplied the fuel and oxidizer under pressure to the three RS-25 main engines in the orbiter. The ET was jettisoned just over 10 seconds after main engine cut-off (MECO) and it re-entered the Earth's atmosphere. Unlike the Solid Rocket Boosters, external tanks were not re-used. They broke up before impact in the Indian Ocean, away from shipping lanes and were not recovered.
The F-1, commonly known as Rocketdyne F-1, is a rocket engine developed by Rocketdyne. This engine uses a gas-generator cycle developed in the United States in the late 1950s and was used in the Saturn V rocket in the 1960s and early 1970s. Five F-1 engines were used in the S-IC first stage of each Saturn V, which served as the main launch vehicle of the Apollo program. The F-1 remains the most powerful single combustion chamber liquid-propellant rocket engine ever developed.
The Angara rocket family is a family of launch vehicles being developed by the Moscow-based Khrunichev State Research and Production Space Center. The launch vehicles are to put between 3,800 kg (8,400 lb) and 24,500 kg (54,000 lb) into low Earth orbit and are intended, along with Soyuz-2 variants, to replace several existing launch vehicles.
A liquid rocket booster (LRB) uses liquid fuel and oxidizer to give a liquid-propellant or hybrid rocket an extra boost at take-off, and/or increase the total payload that can be carried. It is attached to the side of a rocket. Unlike solid rocket boosters, LRBs can be throttled down if the engines are designed to allow it, and can be shut down safely in an emergency for additional escape options in human spaceflight.
The Common Booster Core (CBC) was an American rocket stage, which was used on the Delta IV rocket as part of a modular rocket system. Delta IV rockets flying in the Medium and Medium+ configurations each used a single Common Booster Core as their first stage, while the Heavy configuration used three; one as the first stage and two as boosters. The Common Booster Core was 40.8 metres (134 ft) long, had a diameter of 5.1 metres (17 ft) and was powered by a single RS-68 engine burning liquid hydrogen and liquid oxygen.
The Saturn II was a series of American expendable launch vehicles, studied by North American Aviation under a NASA contract in 1966, derived from the Saturn V rocket used for the Apollo lunar program. The intent of the study was to eliminate production of the Saturn IB, and create a lower-cost heavy launch vehicle based on Saturn V hardware. North American studied three versions with the S-IC first stage removed: the INT-17, a two-stage vehicle with a low Earth orbit payload capability of 47,000 pounds (21,000 kg); the INT-18, which added Titan UA1204 or UA1207 strap-on solid rocket boosters, with payloads ranging from 47,000 pounds (21,000 kg) to 146,400 pounds (66,400 kg); and the INT-19, using solid boosters derived from the Minuteman missile first stage.
The Delta IV Heavy was an expendable heavy-lift launch vehicle, the largest type of the Delta IV family. It was the world's third highest-capacity launch vehicle in operation at the time of its retirement in 2024, behind NASA's Space Launch System and SpaceX's Falcon Heavy and closely followed by CASC's Long March 5. It was manufactured by United Launch Alliance (ULA) and was first launched in 2004. ULA retired the Delta IV Heavy in 2024. Future ULA launches will use the new Vulcan Centaur rocket. Delta IV's final flight was initially scheduled for March 29, 2024 for the National Reconnaissance Office; its actual launch date was April 9, 2024 after a postponement.
The RD-0124 is a rocket engine burning liquid oxygen and kerosene in an oxygen-rich staged combustion cycle, developed by the Chemical Automatics Design Bureau in Voronezh. RD-0124 engines are used on the Soyuz-2.1b and Soyuz-2-1v. A variant of the engine, the RD-0124A, is used on the Angara rocket family's URM-2 upper stage.
A cryogenic rocket engine is a rocket engine that uses a cryogenic fuel and oxidizer; that is, both its fuel and oxidizer are gases which have been liquefied and are stored at very low temperatures. These highly efficient engines were first flown on the US Atlas-Centaur and were one of the main factors of NASA's success in reaching the Moon by the Saturn V rocket.
Universal Rocket Module (URM) is the name of the modular liquid fuelled first and second stage of the Angara expendable launch system. The first stage and booster variant is referred to as URM-1, while the second stage is referred to as URM-2. The URM-2 is derived from the Soyuz-2 Block I second stage.
Fastrac was a turbo pump-fed, liquid rocket engine. The engine was designed by NASA as part of the low cost X-34 Reusable Launch Vehicle (RLV) and as part of the Low Cost Booster Technology project. This engine was later known as the MC-1 engine when it was merged into the X-34 project.
Falcon Heavy is a partially reusable super heavy-lift launch vehicle that can carry cargo into Earth orbit, and beyond. It is designed, manufactured and launched by American aerospace company SpaceX.
Since the founding of SpaceX in 2002, the company has developed four families of rocket engines — Merlin, Kestrel, Draco and SuperDraco — and is currently developing another rocket engine: Raptor, and after 2020, a new line of methalox thrusters.
A super heavy-lift launch vehicle is a rocket that can lift to low Earth orbit a "super heavy payload", which is defined as more than 50 metric tons (110,000 lb) by the United States and as more than 100 metric tons (220,000 lb) by Russia. It is the most capable launch vehicle classification by mass to orbit, exceeding that of the heavy-lift launch vehicle classification.
During the lifetime of the Space Shuttle, Rockwell International and many other organizations studied various Space Shuttle designs. These involved different ways of increasing cargo and crew capacity, as well as investigating further reusability. A large focus of these designs were related to developing new shuttle boosters and improvements to the central tank, but also looked to expand NASA's ability to launch deep space missions and build modular space stations. Many of these concepts and studies would shape the concepts and programs of the 2000s such as the Constellation, Orbital Space Plane Program, and Artemis program.