Pages

Wednesday, August 07, 2024

NASA X-33 Reusable Spaceplane & Linear Aerospike Engine Project (1996-2001)

NASA X-33 Reusable Spaceplane & Linear Aerospike Engine Project (1994-2001)

Developed for NASA's X-33 Advanced Technology Demonstrator, the Boeing Rocketdyne XRS-2200 engine used a linear aerospike arrangement instead of the classic bell nozzle using liquid hydrogen (LH2) fuel and a liquid oxygen (LOX) oxidizer. The design was based on the J-2S, the upgraded version of the Apollo era J-2 engine developed in the 1960s. This shows a test of twin Linear Aerospike XRS-2200 engines, originally built for the X-33 program. It was performed on August 6, 2001 at NASA's Sternis Space Center in Mississippi. The engines were fired for the planned 90 seconds and reached a planned maximum power of 85 percent.
NASA's Second Generation Reusable Launch Vehicle Program, also known as the Space Launch Initiative (SLI), made advances in propulsion technology with this third and final successful engine hot fire, designed to test electro-mechanical actuators that control the flow of propellants in rocket engines.

A NASA SR-71 successfully completed its first flight October 31, 1997 as part of the NASA/Rocketdyne/Lockheed Martin Linear Aerospike SR-71 Experiment (LASRE) at NASA's Dryden Flight Research Center, Edwards, California (now known as the Armstrong Flight Research Center). The SR-71 took off at 8:31 a.m. PST. The aircraft flew for one hour and fifty minutes, reaching a maximum speed of Mach 1.2 before landing at Edwards at 10:21 a.m. PST, successfully validating the SR-71/linear aerospike experiment configuration. The goal of the first flight was to evaluate the aerodynamic characteristics and the handling of the SR-71/linear aerospike experiment configuration. The engine was not fired during the flight.
To provide data before flying on the X-33 vehicle and the RLV, a spacecraft rocket engine was flight-tested atop the NASA SR-71 aircraft as the Linear Aerospike SR-71 Experiment (LASRE). A 20 percent-scale, semispan model of the X-33 vehicle, the aerospike engine, and all the required fuel and oxidizer tanks and propellant feed systems was mounted atop the SR-71 airplane.
This photograph shows a ground cold flow test of the linear aerospike rocket engine mounted on the rear fuselage of an SR-71.
This is an artist's concept of an X-33 Advanced Technology Demonstrator, a subscale protoptye launch vehicle being developed by NASA Lockheed Martin Skunk Works. (Vehicle configuration in October 1997) The X-33 is a subscale prototype of a Reusable Launch Vehicle (RLV) Lockheed Martin has labeled "Venture Star TM." The X-33 program was cancelled in 2001.
Pictured here is an artist's concept of the experimental X-33 in-flight. The X-33 program was designed to pave the way to a full-scale commercially developed, reusable launch vehicle (RLV). 
The wedge-shaped X-33 was a sub-scale technology demonstration prototype of a Reusable Launch Vehicle (RLV). 
This is an artist's concept of the completely operational International Space Station being approached by an X-33 Reusable Launch Vehicle (RLV).

NASA's X-33 program began in 1994 as part of NASA’s Reusable Launch Vehicle (RLV) program. It awarded a contract to Lockheed Martin to build and fly an uncrewed technology demonstrator. Much of the vehicle was entirely new, including the linear aerospace rocket motor and the composite cryogenic propellant tanks. The leap exceeded what existing and developing technology could support. The prototype was to be unpiloted. The X-33, a half-scale vehicle, was expected to feature a lifting-body shape, a new “aerospike” rocket engine, and a rugged metallic thermal protection system. It was expected to demonstrate in flight the new technologies needed for a Reusable Launch Vehicle (RLV). It was designed to take off vertically like a rocket, reaching an altitude of up to 60 miles and speeds between Mach 13 and 15, and to land horizontally like an airplane.

Through demonstration flights and ground research, NASA's X-33 program was to provide the information needed for commercial firms, such as Lockheed Martin (builder of the X-33 Venture Star), to decide by the year 2000 whether to proceed with the development of a full-scale, commercial RLV program. The program was intended to put the U.S. on a path toward safe, affordable, reliable access to space by providing the latest spaceflight technology. 

The X-33 was to be the flagship demonstrator for technologies designed to dramatically lower the cost of access to space. This program would in turn create new opportunities for space access and significantly improve U.S. economic competitiveness in the worldwide launch marketplace. NASA would be a customer, not the operator in the commercial RLV. The X-33 program was cancelled in 2001. It is reported that failures of its 21-meter wingspan and multi-lobed, composite-material fuel tank during pressure testing ultimately led to the withdrawal of federal support for the program in early 2001.

Conceived of in the 1960's, aerospike engines had not yet beeen flown, and many questions remained regarding aerospike engine performance and efficiency in flight. To provide data before flying on the X-33 vehicle and the RLV, a spacecraft rocket engine was flight-tested atop the NASA SR-71 aircraft as the Linear Aerospike SR-71 Experiment (LASRE). A 20 percent-scale, semispan model of the X-33 vehicle, the aerospike engine, and all the required fuel and oxidizer tanks and propellant feed systems was mounted atop the SR-71 airplane for this experiment. A major technical objective of the LASRE flight test was to obtain installed-engine performance flight data for comparison to wind-tunnel results and for the development of computational fluid dynamics-based design methodologies. Five flights of the LASRE and firing the rocket engine using inert liquid nitrogen and helium in place of liquid oxygen and hydrogen were successfully completed.

NASA announced March 1, 2001, that it would not add Space Launch Initiative funds to the X-33 program. As a result, the X-33 program came to completion when the cooperative agreement between NASA and Lockheed Martin expired March 31, 2001. NASA invested nearly $1 billion in the project, and Lockheed Martin put in nearly $400 million.

Learn more about the XRS-2200 Linear Aerospike Engine:

Read the article: "X-33/VentureStar – What really happened" by Chris Bergin at NASASpaceflight

Image Credits: NASA's Marshall Space Flight Center (Alabama), Armstrong Flight Research Center (California), Stennis Space Center (Mississippi)
Image Dates: 1997-2004

#NASA #Space #CommercialSpace #X33 #X33Program #BoeingRocketdyne #XRS2200Engines #RLVProgram #SpaceTechnology #TechnologyDevelopment #ResearchProject #Aerospace #LASREFlightTests #SR71Aircraft #SR71 #Aviation #LockheedMartin #NASAStennis #MSFC #AFRC #UnitedStates #History #ArtistConcepts #STEM #Education

No comments:

Post a Comment