 The Personnel Launch System, or PLS, is a vehicle which could provide future transport of people and small cargo to and from low-Earth orbit. Although not presently approved for development, the PLS is being designed to complement the space shuttle and is being considered as a future addition to the manned launch capability of the United States. In the era of space station freedom and subsequent missions of the Space Exploration Initiative, it may be important that the United States have an alternate means of getting people and small cargo to low-Earth orbit and back. The two designs being considered for PLS differ in their aerodynamic properties and mission capabilities. While the Johnson Space Center's approach uses a biconic-shaped capsule with a parachute landing, the Langley Research Center's design designated the HL-20 is a winged lifting body which could make conventional runway landings on return from orbit. Unlike the space shuttle, the PLS would have, as a design objective, a launch abort capability to safely recover the crew during ascent. Predating and influencing the design of the space shuttle, several lifting body aircraft, including the HL-10, were flown by test pilots during the period from 1966 to 1975. Over the past few years, the HL-20 has undergone considerable analysis at Langley and has evolved into a mature design with capabilities which adequately satisfy the PLS design and mission requirements. A lifting body spacecraft such as the HL-20 and the HL-10 shown here would have several advantages over other shapes. The spacecraft would fly over large land areas and the number of available landing opportunities would be increased. The runway landings would be possible, permitting simple, cost-effective precision recovery at many sites around the world, including the Kennedy Space Center launch site. The primary mission of the PLS would be to deliver passengers to the space station freedom. Typically, a space station crew of eight would be delivered by a two-person PLS flight crew. With an overall length of 29.5 feet and span across the wingtips of 23.5 feet, the HL-20 concept would be a much smaller craft than the space shuttle orbiter and will fit within the payload bay of the shuttle with wings folded. Using the extensive one-tunnel resources at Langley, researchers compiled a comprehensive aerodynamic and aerothermodynamic database on the HL-20 concept, spanning the entire speed range which the PLS will fly. Several models were built for testing the various tunnels, ranging from a six-foot model used for forces and moments test at low speeds to six-inch models used in hypersonic tests. Results have shown the shape possesses good flying qualities in all speed regimes. Computational fluid dynamics or CFD codes have been used at Langley to study flow field characteristics of the HL-20. These advanced computational grid techniques were used in conjunction with one-tunnel tests to study patterns of flow field phenomena, shock waves, stability and control, and heating on the windward and leeward surfaces of the vehicle. It was found that heating predicted by this concept will be within the limits of space shuttle-based high-temperature reusable surface insulation, except at the nose where shuttle-based carbon-carbon will be required. In addition to computer modeling of vehicle controllability during entry, a flight simulator has been set up at Langley to permit pilots to study the final landing phase of flight. Starting at 15,000 feet, the simulation presents a realistic view of the approach to a runway landing. Using a side-stick controller and a minimum of instrumentation, pilots including one who flew the X-15 rocket plane and the lifting bodies have demonstrated this configuration to be controllable and capable of pinpoint landings. A cooperative agreement between NASA and North Carolina State and North Carolina A&T universities led to the construction of a full-scale model of the HL-20 PLS for use in further research of this concept. With requirements furnished by Langley, university instructors and students designed the research model during their 1990 spring semester with construction following during the summer. The research objectives of the HL-20 model are to assess crew in-grass and e-grass operations, assess crew volume and habitability, examine fit checks of various subsystems arrangements, and determine visibility requirements for the crew during critical docking and landing operations. The model will be moved to the Langley Research Center where human factors or search will be conducted. Later, the model will be located at the Johnson Space Center where the research effort will involve members of the astronaut corps who will evaluate the HL-20 for operations efficiency. The Langley Research Center has defined a lifting body PLS for assured manned access to space for future U.S. space missions. This reusable vehicle designated the HL-20 has been designed for safe and reliable operations, improved operability, maintainability and affordability, and has the potential for reducing life cycle cost associated with placing people in orbit.