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The MARC-60 (Mitsubishi Aerojet Rocketdyne Collaboration), also known as MB-60, MB-XX, and RS-73, is a
liquid-fuel cryogenic rocket engine
A rocket engine uses stored rocket propellants as the reaction mass for forming a high-speed propulsive jet of fluid, usually high-temperature gas. Rocket engines are reaction engines, producing thrust by ejecting mass rearward, in accorda ...
designed as a collaborative effort by
Japan's Mitsubishi Heavy Industries
is a Japanese multinational engineering, electrical equipment and electronics corporation headquartered in Tokyo, Japan. MHI is one of the core companies of the Mitsubishi Group and its automobile division is the predecessor of Mitsubishi Mo ...
and
US' Aerojet Rocketdyne
Aerojet Rocketdyne is an American manufacturer of rocket, hypersonic, and electric propulsive systems for space, defense, civil and commercial applications. Headquartered in Sacramento, California, the company is owned by Aerojet Rocketdyne Hold ...
.
The engine burns cryogenic
liquid oxygen
Liquid oxygen—abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries—is the liquid form of molecular oxygen. It was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by Robert H. Goddard, an app ...
and
liquid hydrogen
Liquid hydrogen (LH2 or LH2) is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form.
To exist as a liquid, H2 must be cooled below its critical point of 33 K. However, for it to be in a fully l ...
in an
open expander cycle, driving the
turbopumps
A turbopump is a propellant pump with two main components: a rotodynamic pump and a driving gas turbine, usually both mounted on the same shaft, or sometimes geared together. They were initially developed in Germany in the early 1940s. The purpo ...
with waste heat from the main combustion process.
Description
The MB-XX program shared the development duties of the engines between
Boeing's Rocketdyne
Rocketdyne was an American rocket engine design and production company headquartered in Canoga Park, in the western San Fernando Valley of suburban Los Angeles, in southern California.
The Rocketdyne Division was founded by North American Avia ...
division (now
Aerojet Rocketdyne
Aerojet Rocketdyne is an American manufacturer of rocket, hypersonic, and electric propulsive systems for space, defense, civil and commercial applications. Headquartered in Sacramento, California, the company is owned by Aerojet Rocketdyne Hold ...
) and the Japanese
Mitsubishi Heavy Industries
is a Japanese multinational engineering, electrical equipment and electronics corporation headquartered in Tokyo, Japan. MHI is one of the core companies of the Mitsubishi Group and its automobile division is the predecessor of Mitsubishi Mo ...
. Under the agreement, Boeing develops the
LOX
Liquid oxygen—abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries—is the liquid form of molecular oxygen. It was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by Robert H. Goddard, an appli ...
and
LH turbopumps
A turbopump is a propellant pump with two main components: a rotodynamic pump and a driving gas turbine, usually both mounted on the same shaft, or sometimes geared together. They were initially developed in Germany in the early 1940s. The purpo ...
and the
nozzle, while MHI develops the thrust chamber assembly (TCA), control systems,
gimbal bearing,
heat exchanger
A heat exchanger is a system used to transfer heat between a source and a working fluid. Heat exchangers are used in both cooling and heating processes. The fluids may be separated by a solid wall to prevent mixing or they may be in direct conta ...
, and ducts. The TCA of the engine consists of the main combustion chamber, the
regeneratively cooled portion of the nozzle, the injector, and the ignition system.
Under the MB-XX program two engines were developed: the MARC-60 (MB-60) and the MB-35. Please note that the below table uses specifications as listed in 2003, and the MARC-60 engine has since then evolved.
History
The MARC-60's (then MB-60) development program was announced on 14 February 2000 by
Boeing's Rocketdyne
Rocketdyne was an American rocket engine design and production company headquartered in Canoga Park, in the western San Fernando Valley of suburban Los Angeles, in southern California.
The Rocketdyne Division was founded by North American Avia ...
division and
Japan's Mitsubishi Heavy Industries
is a Japanese multinational engineering, electrical equipment and electronics corporation headquartered in Tokyo, Japan. MHI is one of the core companies of the Mitsubishi Group and its automobile division is the predecessor of Mitsubishi Mo ...
, as a part of the MB-XX family of cryogenic upper stage rocket engines.
The aim of the MB-XX program was to develop an engine with "robust operating margins, high reliability, increased thrust, and high specific impulse at an affordable cost".
The MB-XX family of engines was intended to be used on new or upgraded upper stages of
Boeing's Delta IV
Delta IV is 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, t ...
and
MHI's H-IIA
H-IIA (H-2A) is an active expendable launch system operated by Mitsubishi Heavy Industries (MHI) for the Japan Aerospace Exploration Agency. These liquid fuel rockets have been used to launch satellites into geostationary orbit; lunar o ...
families of launch vehicles. Potential applications also included
Lockheed Martin's Atlas V
Atlas V is an expendable launch system and the fifth major version in the Atlas launch vehicle family. It was originally designed by Lockheed Martin, now being operated by United Launch Alliance (ULA), a joint venture between Lockheed Mart ...
.
Both Delta IV and Atlas V are now operated by
United Launch Alliance
United Launch Alliance (ULA), legally United Launch Alliance, LLC, is an American spacecraft launch service provider that manufactures and operates a number of rocket vehicles that are capable of launching spacecraft into orbits around Earth, ...
.
Development of the MB-XX family of engines was started in early 1999.
From 2000 to 2001, market forces drove the focus of the MB-XX program from the 267 kN (60,000 lbf) MB-60 to the 156 kN (35,000 lbf) MB-35. The MB-35 was not a new design, instead the existing MB-60 design was tuned to operate at the lower thrust level. The MB-35 was designed to be a modern, drop-in replacement for the
Aerojet Rocketdyne
Aerojet Rocketdyne is an American manufacturer of rocket, hypersonic, and electric propulsive systems for space, defense, civil and commercial applications. Headquartered in Sacramento, California, the company is owned by Aerojet Rocketdyne Hold ...
RL10
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. Three RL10 ve ...
.
Component-level testing of the MB-XX demonstrator was completed in 2004, and a system-level demonstrator engine was successfully hot-fired in September 2005.
In 2013,
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the US federal government responsible for the civil List of government space agencies, space program ...
was evaluating MARC-60 as the engine of choice for the
Space Launch System's Exploration Upper Stage
The Exploration Upper Stage (EUS) is being developed as a large second stage for Block 1B and Block 2 of the Space Launch System (SLS), succeeding Block 1's Interim Cryogenic Propulsion Stage. It will be powered by four RL10C-3 engines burning ...
(EUS). The study explored the possibility of utilizing two MARC-60 engines in place of four
RL10
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. Three RL10 ve ...
engines, as well as the possibility of the stage using a single
J-2X
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 Rocke ...
engine. Under the plan, the engine's control unit would have been provided by NASA. The proposal also resulted in the engine being renamed to MARC-60, as Rocketdyne had changed hands multiple times after the MB-60's (Mitsubishi Boeing-Rocketdyne) inception in 1999. In 2016 NASA announced that the
EUS would be powered by four
RL10C-3 engines, dropping both MARC-60 and
J-2X
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 Rocke ...
.
See also
*
RL60
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 was ...
, a LOX/LH expander cycle engine of same thrust and weight class
*
RL10
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. Three RL10 ve ...
, the closed expander cycle LOX/LH engine that was supposed to be replaced by MB-35, the down-scaled version of MARC-60
References
{{Reflist
Rocketdyne engines
Rocket engines
Rocket engines using the expander cycle