https://ntrs.nasa.gov/search.jsp?R=19960053992 2020-06-16T03:45:49+00:00Z View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by NASA Technical Reports Server :.,.,.a m NASA-TM-110473 IAF 96-V.4.01 Reusable Launch Vehicle Technology Program Delma C. Freeman, Jr. Theodore A. Talay NASA Langley Research Center Hampton, Virginia USA R. Eugene Austin NASA Marshall Space Flight Center Marshall Space Flight Center, Alabama USA 47th International Astronautical Congress October 7-11, 1996/Beijing, China For permission to copy or republish, contact the American International Astronautical Federation 3-5, Rue Mario-Nikis, 75015 Paris, France REUSABLE LAUNCH VEHICLE TECHNOLOGY PROGRAM Delma C. Freeman, Jr.* and Theodore A. Talay** NASA Langley Research Center Hampton, Virginia USA 23681-0001 R. Eugene Austint NASA Marshall Space Flight Center Marshall Space Flight Center, Alabama USA 35812-1000 ABSTRACT NOMENCLATURE APS Industry/NASA Reusable Launch Vehicle (RLV) Auxiliary Propulsion System APU Technology Program efforts are underway to design, test, Auxiliary Power Unit BMDO Ballistic Missile Defense Agency and develop technologies and concepts for viable com- CAN mercial launch systems that also satisfy national needs Cooperative Agreement Notice DoD at acceptable recurring costs. Significant progress has Department of Defense been made in understanding the technical challenges of DC-X Delta Clipper Experimental DC-XA Delta Clipper Experimental Advanced fully reusable launch systems and the accompanying EELV Evolved Expendable Launch Vehicle management and operational approaches for achieving a graphite epoxy low-cost program. Gr-Ep LH2 liquid hydrogen LO2 This paper reviews the current status of the Reus- liquid oxygen able Launch Vehicle Technology Program including the MSFC Marshall Space Flight Center DC-XA, X-33 and X-34 flight systems and associated NASP National Aero-Space Plane NRA NASA Research Announcement technology programs. It addresses the specific technolo- RLV Reusable Launch Vehicle gies being tested that address the technical and operabil- SSRT Single Stage Rocket Technology ity challenges of reusable launch systems including reusable cryogenic propellant tanks, composite structures, SSTO Single stage to orbit thermal protection systems, improved propulsion, and STS Space Transportation System TPS Thermal Protection System subsystem operability enhancements. The recently con- cluded DC-XA test program demonstrated some of these INTRODUCTION technologies in ground and flight tests. Contracts were awarded recently for both the X-33 and X-34 flight dem- Cost effective, reliable space transportation is a ma- onstrator systems. The Orbital Sciences Corporation X-34 flight test vehicle will demonstrate an air-launched reus- jor focus of current government and commercial launch able vehicle capable of flight to speeds of Mach 8. The industry efforts. The paths to this goal range from incre- Lockheed-Martin X-33 flight test vehicle will expand the mental improvements to existing launch systems, such test envelope for critical technologies to flight speeds of as the Department of Defense (DoD) Evolved Expend- Mach 15. A propulsion program to test the X-33 linear able Launch Vehicle (EELV) program, to new systems aerospike rocket engine using a NASA SR-71 high speed that hold the promise of opening the space frontier to a aircraft as a test bed is also discussed. The paper also variety of new space industries. In the latter case, the describes the management and operational approaches National Aeronautics and Space Administration (NASA) that address the challenge of new cost-effective, reus- Reusable Launch Vehicle (RLV) Technology program able launch vehicle systems. is seeking a near-term replacement for the Space Shuttle. *Director, Aerospace Transportation Technology Office, The RLV Technology program has as a goal the de- AIAA Fellow. velopment of an all rocket, fully reusable single-stage- to-orbit (SSTO) vehicle. It has several major elements: **Aerospace Engineer, Space Systems and Concepts Division. the X-33 Advanced Technology Demonstrator, the X- 34 Testbed Technology Demonstrator, and the upgraded I'X-33 Program Manager, Member AIAA. DC-XA Flight Demonstrator. The purpose of this paper Copyright © American Institute of Aeronautics and Astronautics, Inc. No copyright is asserted in the United States under Title 17, U.S. Code. The U.S. Government has a royalty-free license to exercise all rights under the copyright claimed herein for Governmental Purposes. All other rights are reserved by the copyright owner. istoreviewthecurrentstatusof theReusableLaunch In January 1995, two Cooperative Agreement No- VehicleTechnologyprogram.Itexamineshowtheseel- tices (CAN 8-1 and 8-2) _'2were issued by the NASA call- ementsaddressthetechnicalandoperabilitychallenges ing for design and development of a (I) Reusable Launch ofreusablelaunchvehicleswhosesolutionsareneces- Vehicle Advanced Technology Demonstrator designated sarytoreducerecurringcosts.Managementandopera- the X-33, and a (2) Reusable Launch Vehicle Small Re- tionalapproachesthataddressthechallengeof new usable Booster designated the X-34. cost-effective,reusablelaunchvehiclesystemsarealso discussed. NASA's intent with the X-33 solicitation is to dem- onstrate critical elements of a future SSTO rocket pow- REUSABLE LAUNCH VEHICLE ered RLV by stimulating the joint industry/Government TECHNOLOGY PROGRAM OVERVIEW funded concept definition/design of a technology dem- onstrator, the X-33, followed by design and flight dem- The goal of the RLV Technology program is the low- onstrations of one or more competitive concepts. The ering of the cost of access to space to promote the cre- X-33 must adequately demonstrate key design and op- ation and delivery of new space services and other erational aspects of a future commercially viable RLV. activities that will improve economic competitiveness. To this end, the program supports the development of an The intent of the X-34 solicitation was originally to all rocket, fully reusable SSTO. However, the private stimulate the joint industry/government funded develop- sector is free to ultimately select the operational RLV ment of a small reusable, or partially reusable, booster configuration to be flown in the post-2000 time frame. that had potential application to commercial launch ve- hicle capabilities to provide significantly reduced mis- The RLV Technology program has several major sion costs for placing small payloads (1,000-2,000 lb) elements that together support its objectives. These ele- into a low Earth orbit starting in 1998. Importantly, from ments are synergistic as illustrated in Figure 1. the NASA perspective, the CAN stated that "the booster must demonstrate technologies applicable to future re- usable launch vehicles." Cole Technology Program • I_tmabte c_ tank DC-X, DC-XA • Graphite cx:)mposao pnmary m m structures E I • Ad_mK:ecl themll protection t_. em_Je_qremnnnm m m In 1990, the Ballistic Missile Defense Organization * Advanced propulsion (BMDO) initiated the Single Stage Rocket Technology • Avk:_k;s/opembte systems (SSRT) program to demonstrate the practicality, reliabil- Next GenerMIon X Vehidel • DC-XA ity, operability and cost efficiency of a fully reusable, • Operations • Advanced technology rapid turnaround single-stage rocket. Following an ini- • Advsnc_ Technology tial design competition phase, BMDO awarded Dernonsllator: X-33 . Operatior_s McDonnell Douglas a $59M contract in August 1991, • Vehicle sy stm'ml. with the primary emphasis on the design and manufac- . Small Reusable Launch VohP..le Techrc.logy (_Jmo_strator: X-34 ture of a low-speed rocket demonstrator vehicle named • Hypersonlcs • Of)erllllOnS the DC-X (Delta Clipper Experimental), Figure 2, a subscale version of the Delta Clipper vertical takeoff, Figure 1. Reusable Launch Vehicle Technology vertical landing SSTO under study by McDonnell Dou- Program Schedule. glas. The goals of the DC-X program 3 were a demon- stration of rapid prototyping of hardware and software, The core technology program, initiated in early 1994, demonstration of vertical takeoff and landing, aircraft- supports design and manufacture of key technology ele- like operations, and rapid system turnaround. ments necessary for an operational RLV. Testing of ini- tial demonstration articles took place using the DC-XA The DC-X achieved a rapid prototyping development flight test vehicle during the summer of 1996. The core and flew for the first time two years after award of the technology program implements the National Space contract. From August 18, 1993 through July 7, 1995, Transportation Policy that specifies, "Research shall be the vehicle flew eight test flights with the test envelope focused on technologies to support a decision no later expanded with each succeeding flight. The last three than December 1996 to proceed with a sub-scale flight flights in particular demonstrated engine differential demonstration which would prove the concept of single- throttling for flight control, the use of a gaseous oxygen/ stage to orbit." hydrogen reaction control thruster module, and engine named DC-XA (A for Advanced), the vehicle was modi- fied by McDonnell Douglas to test several key technolo- gies of the RLV program. Changes, depicted in Figure 3, included (1) a switch from an aluminum oxygen tank to a Russian-built aluminum-lithium alloy cryogenic oxy- gen tank with external insulation, (2) a switch from an aluminum cryogenic hydrogen