Space Flight and Space Technology
Reusable Launch Vehicles and Other Launch Systems
NASA initiated the RLV technology development and demonstration program in early FY 1995 in response to the National Space Transportation Policy of 1994. DoD worked with NASA on this program, bringing expertise in such areas as flight test, operations, and composite structures. NASA has structured the RLV program differently from previous similar programs, with new relationships between Government and industry, a faster program pace, and a streamlined management structure. NASA managers designed the RLV program to benefit the broad range of future space launch needs, from the emerging small payloads market to the future supply needs of the International Space Station.
In FY 1995, the Air Force's Phillips Laboratory continued the series of flight experiments begun in 1994, using the McDonnell Douglas Delta Clipper-Experimental (DC-X) launch vehicle. The DC-X was designed to test the feasibility of a vertical landing liquid oxygen and hydrogen rocket operated with the same simplicity as conventional aircraft. While the DC-X is a simplified demonstration vehicle, many of the concepts that it incorporates would be necessary for an actual cost-effective RLV. The year began with the repair of damage to the DC-X vehicle from an explosion in a ground utility trench during the previous flight test in June 1994. The vehicle, which had successfully completed a controlled emergency landing after the explosion, required repairs to the aeroshell and the liquid hydrogen tank. On May 16, 1995, the DC-X resumed test flights, traveling vertically 1,150 feet and then moving laterally until it was positioned over its landing pad located 350 feet from the flight stand. On June 12, 1995, the DC-X climbed to 5,700 feet and demonstrated for the first time the use of four gaseous oxygen-hydrogen thrusters. In the eighth and final test flight of the DC-X configuration, on July 7, 1995, the DC-X demonstrated a reentry rotation maneuver, first pointing its nose 10 degrees below the horizon and then rotating 138 degrees to land with the nose pointing up. This maneuver would be required by a full-scale vertical landing RLV. At the conclusion of the flight tests, the Air Force transferred the DC-X to NASA to be upgraded for a series of flight tests in 1996 as the DC-XA (Delta Clipper-Experimental Advanced).
NASA initiated a second element of the RLV program, the X-34, through a Cooperative Agreement Notice (CAN) with Orbital Sciences Corporation in the early part of 1995. The X-34 was to demonstrate advanced vehicle technologies in flight for a fully reusable booster that has the promise of reducing costs in the small launcher market by about 50 percent. The X-34 was to progress rapidly through hardware design and development to flight demonstrations in 1997.
NASA also initiated the X-33 program, the third RLV flight test program, through a CAN in early 1995. As in the total RLV program, the X-33 is a NASA partnership with industry, with industry as the lead. The X-33 will demonstrate critical operations and component technologies on the ground and in flight to permit a decision at the end of the decade on the technical feasibility of single-stage-to-orbit (SSTO), as well as the viability of private financing for the next generation of launch vehicles. During FY 1995, the X-33 program was in the design phase, with three industry teams led by Lockheed Martin, McDonnell Douglas Aerospace, and Rockwell International in competition through 1996.
RLV program managers have committed themselves to developing new operations and component technologies, as well as to producing an industry-Government relationship that will revolutionize the space launch industry worldwide. If successful, the RLV program will deliver "leapfrog" technology that will permit the U.S. space launch industry to regain worldwide leadership in low-cost space launch operations. The staff of DoT's Office of Commercial Space Transportation (OCST) provided technical and analytical support, as part of the Non-Advocate Review Team for the RLV technology program, to ensure that commercial launch services requirements will be taken into account in the development of this technology.
A significant first step in modernizing America's spacelift fleet took place in August 1995 when DoD selected four prime contractors for its Evolved Expendable Launch Vehicle (EELV) Low Cost Concept Validation program. The EELV is to use existing technology to develop a family of ELV's to replace the current medium- and heavy-lift vehicles and supporting infrastructure. The goal is to reduce overall launch system costs by 25 to 30 percent by moving away from current space launch vehicles such as the Titan, Atlas, and Delta vehicles, while also maintaining or improving these current systems' operability and reliability. OCST provided technical assistance and policy analysis as a member of DoD's Source Selection Advisory Board for a review of the EELV program.
Curator: Lillian Gipson|
Last Updated: September 5, 1996
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