Rocket engines using hydrogen propellant

family of rocket stages which can be used as a space tug

The RS-25, also known as the Space Shuttle Main Engine (SSME), is a liquid-fuel cryogenic rocket engine that was used on NASA's Space Shuttle and is used on the Space Launch System.

cryogenic rocket engine by Rocketdyne

The RS-68 (Rocket System-68) was a liquid-fuel rocket engine that used liquid hydrogen (LH2) and liquid oxygen (LOX) as propellants in a gas-generator cycle. It was the largest hydrogen-fueled rocket engine ever flown.

The RL10 is a liquid-fuel cryogenic rocket engine built in the United States by Aerojet Rocketdyne that burns cryogenic liquid hydrogen and liquid oxygen propellants. Modern versions produce up to of thrust per engine in vacuum. RL10 versions were produced for the Centaur upper stage of the Atlas V and the DCSS of the Delta IV. More versions are in development or in use for the Exploration Upper Stage of the Space Launch System and the Centaur V of the Vulcan rocket.

family of European first stage rocket engines

The RD-0120 (, GRAU index: 11D122) was the Energia core rocket engine, fueled by LH/LOX, roughly equivalent to the RS-25 (Space Shuttle Main Engine, SSME). These were attached to the Energia core rather than the orbiter, so were not recoverable after a flight, but created a more modular design (the Energia core could be used for a variety of missions besides launching the shuttle). The RD-0120 and the RS-25 have both similarities and differences. The RD-0120 achieved a slightly higher specific impulse and combustion chamber pressure with reduced complexity and cost (but it was single-use), as

The HM7B was a European cryogenic upper stage rocket engine used on the vehicles in the Ariane rocket family. It was replaced by Vinci, which acts as the new upper stage engine on Ariane 6. Nearly 300 engines have been produced to date.

BE-3 (Blue Engine 3) is a cryogenic rocket engine using liquid hydrogen and liquid oxygen as propellants. Blue Origin began BE-3 development in the early 2010s and the engine completed acceptance testing in early 2015. The BE-3PM variant is used on the New Shepard suborbital rocket, which made its first test flight on April 29, 2015, and had its first crewed flight on July 20, 2021. The BE-3U variant is used on the second stage of the New Glenn orbital rocket, which made its inaugural flight on January 16, 2025.

model of European hydrolox upper stage rocket engine

rocket stage used in Delta rockets

Hybrid ramjet and rocket engine

The CE-20 is a cryogenic rocket engine developed by the Liquid Propulsion Systems Centre (LPSC), a subsidiary of ISRO. It has been developed to power the upper stage of the LVM3. It is the first Indian cryogenic engine to feature a gas-generator cycle. The high thrust cryogenic engine is the most powerful upper stage cryogenic engine in operational service.

rocket engine used on the first stages of Titan rockets

The J-2X is a liquid-fueled cryogenic rocket engine that was planned for use on the Ares rockets of NASA's Constellation program, and later the Space Launch System. Built in the United States by Aerojet Rocketdyne (formerly, Pratt & Whitney Rocketdyne), the J-2X burns cryogenic liquid hydrogen and liquid oxygen propellants, with each engine producing of thrust in vacuum at a specific impulse (Isp) of . The engine's mass is approximately 2,470 kg (5,450 Lb), significantly heavier than its predecessors.

right|thumb|150px|LE-5 The LE-5 liquid rocket engine and its derivative models were developed in Japan to meet the need for an upper stage propulsion system for the H-I and H-II series of launch vehicles. It is a cryogenic bipropellant design, using LH and LOX. Primary design and production work was carried out by Mitsubishi Heavy Industries. In terms of liquid rockets, it is a fairly small engine, both in size and thrust output, being in the 89 kN (20,000 lbf) and the more recent models the 130 kN (30,000 lbf) thrust class.

The RD-0146 () is a liquid-fuel cryogenic rocket engine developed by KBKhA Kosberg in Voronezh, Russia.

thumb|250px|LE-7A, (Mitsubishi Heavy Industries show-room, Shinagawa, Japan)

The YF-77 is China's first cryogenic rocket engine developed for booster applications. It burns liquid hydrogen fuel and liquid oxygen oxidizer using a gas generator cycle. A pair of these engines powers the LM-5 core stage. Each engine can independently gimbal in two planes. Although the YF-77 is ignited prior to liftoff, the LM-5's four strap-on boosters provide most of the initial thrust in an arrangement similar to the European Vulcain on the Ariane 5 or the Japanese LE-7 on the H-II.

rocket propulsion system requiring low-temperature fuels

The YF-75 is a liquid cryogenic rocket engine burning liquid hydrogen and liquid oxygen in a gas generator cycle. It is China's second generation of cryogenic propellant engine, after the YF-73, which it replaced. It is used in a dual engine mount in the H-18 third stage of the Long March 3A, Long March 3B and Long March 3C launch vehicles. Within the mount, each engine can gimbal individually to enable thrust vectoring control. The engine also heats hydrogen and helium to pressurize the stage tanks and can control the mixture ratio to optimize propellant consumption.

The YF-73 was China's first successful cryogenic liquid hydrogen fuel and liquid oxygen oxidizer gimballed engine. It was used on the Long March 3 H8 third stage, running on the simple gas generator cycle and with a thrust of . It had four hinge mounted nozzles that gimbaled each on one axis to supply thrust vector control and was restart capable. It used cavitating flow venturis to regulate propellant flows. The gas generator also incorporated dual heat exchangers that heated hydrogen gas, and supplied helium from separate systems to pressurize the hydrogen and oxygen tanks. The engine was re

KVD-1 was an upper stage LOX/LH cryogenic engine developed by the Isayev Design Bureau (now KB KhIMMASH) of Russia in the early 1960s. It is a modified version of the RD-56, developed for a never-completed cryogenic upper stage of the N-1 super-heavy lift rocket, with the goal of enabling crewed lunar missions by the USSR. The KVD-1 produces a thrust of 7.5 tonnes.

Shuttle-Centaur was a version of the Centaur upper stage rocket designed to be carried aloft inside the Space Shuttle and used to launch satellites into high Earth orbits or probes into deep space. Two variants were developed: Centaur G-Prime, which was planned to launch the Galileo and Ulysses robotic probes to Jupiter, and Centaur G, a shortened version planned for use with United States Department of Defense Milstar satellites and the Magellan Venus probe. The powerful Centaur upper stage allowed for heavier deep space probes, and for them to reach Jupiter sooner, prolonging the operational

The RL60 was a planned liquid-fuel cryogenic rocket engine designed in the United States by Pratt & Whitney, burning cryogenic liquid hydrogen and liquid oxygen propellants. The engine runs on an expander cycle, running the turbopumps with waste heat absorbed from the main combustion process. This high-efficiency, waste heat based combustion cycle combined with the high-performance liquid hydrogen fuel enables the engine to reach a very high specific impulse of up to 465 seconds in a vacuum. The engine was planned to be a more capable successor to the Aerojet Rocketdyne RL10, providing improve

The YF-75D is a cryogenic rocket engine burning liquid hydrogen and liquid oxygen in a closed expander cycle. It is China's third generation of upper stage cryogenic propellant engine, after the YF-73 and the YF-75. It is used in a dual engine mount in the H5-2 second stage of the Long March 5 launch vehicles. Within the mount, each engine can gimbal individually to enable thrust vectoring control. As with its predecessor YF-75, the YF-75D can adjust its mixture ratio to optimize propellant consumption. As an additional improvement it can do multiple restarts, against the single one of its pre

largest rocket engine to be designed

U.S. Air Force project in the 1990s and early 2000s

The LE-9 is a liquid cryogenic rocket engine burning liquid hydrogen and liquid oxygen in an expander bleed cycle. Two or three will be used to power the core stage of the H3 launch vehicle.

The CE-7.5 is a cryogenic rocket engine developed by ISRO to power the upper stage of its GSLV Mk-2 launch vehicle. The engine was developed as a part of the Cryogenic Upper Stage Project (CUSP). It replaced the KVD-1 (RD-56) Russian cryogenic engine that powered the upper stage of GSLV Mk-1.

The RD-701 (', Rocket Engine 701') was a liquid-fuel rocket engine proposed by Energomash, Russia (USSR at that time). It was briefly proposed to propel the reusable MAKS space plane, but the project was cancelled shortly before the end of USSR. The RD-701 would have been a tripropellant engine that used a staged combustion cycle with afterburning of oxidizer-rich hot turbine gas. The RD-701 would have had two modes. Mode 1 used three components: LOX as an oxidizer and a fuel mixture of RP-1 / LH2 which is used in the lower atmosphere. Mode 2'' would have also used LOX, with LH2 as fuel in vac