Reusable Launch Vehicle Program Research Articles

At the threshold: emerging opportunities for expanding commercial and governmental space operations in the new century: The 1997 KRAFT EHRICKE Lecture for the 27th Symposium on Economics in Space Operations of the IAA

We stand at the threshold of a new era in space operations in which a host of potentially profound changes will occur in space systems concepts and technologies. Many of the space systems in use today were originally created in the mid- to late-1960s, based on technologies either already existing or then under development. These concepts—including satellites, launchers and piloted systems—have served well for government and commercial missions during the decades since that era. They will continue to serve—and serve well—as we enter the first decade of the next century. However, in this era of restraint in government spending on civilian space and dramatic growth in investments in existing space commercial ventures, new, breakthrough systems concepts that drive down costs are critically needed. Fortunately these new concepts appear to be at hand. Building on the research foundation of the past 20 years, an array of new technologies are emerging which may make possible highly innovative advanced systems concepts. These technologies include long-lived high-efficiency chemical propulsion, affordable megawatt-class space power systems, advanced electromagnetic systems, breakthrough materials, “brilliant” space machines, robust artificial intelligences onboard and on the ground, low-cost utilization of local resources, and others. Moreover, many of these technologies appear common to both new space industries and very affordable future government missions. Forerunners of this new era can be seen today in the systems of large telecommunications satellite constellations such as the Iridium venture and in the technologies of the reusable launch vehicle program. Driving down the cost of space access will be the linchpin for this prospective future. In addition, during the coming decade, a wide range of civilian government space investments will likely be focused on vitally-needed research and development. Our choices now are exceptionally important and must be made wisely. We stand at the threshold. Across a broad technological frontier, diverse opportunities are emerging that might well make possible the creation of revolutionary systems concepts and a dramatic expansion of new space industries, while also enabling bold, but affordable missions of human exploration beyond Earth orbit.

Highly reusable space transportation: Advanced concepts and the opening of the space frontier

Revolutionary changes in how cargo and people are transported into space are needed to enable the affordable development and exploration of space in the 21st century. Diverse efforts to achieve major, but incremental Earth-to-orbit (ETO) improvements in the relatively near term have been undertaken in recent years in the US, including the Department of Defense evolved expendable launch vehicle system development project. The NASA-industry reusable launch vehicle (RLV) program is addressing this challenge for the mid-term. The RLV program will validate the technology to enable industry to develop all-rocket reusable launch systems that can deliver payloads from the current Civil Needs Data Base in the 20,000–40,000 pounds class and smaller to low Earth orbit (LEO) at costs of approximately $1000–$2000 per pound. This represents a factor of 5 (or more) reduction below existing launch services. This “next generation” improvement in launch capability is a vital element of the US National Space Transportation policy for current and planned government and commercial payloads. The longer-term challenge is also being addressed. During 1995–1997, NASA conducted the highly reusable space transportation (HRST) study project to address the longer-term challenge: how to achieve an additional factor of 10 reduction in launch costs—to approximately $100–$200 per payload pound to LEO—thus enabling a revolutionary expansion of space activity and enterprise. The HRST study has identified a “grand strategy” for achieving these cost goals, based on pursuing a revolutionary advance in main propulsion architectures and technology for ETO systems to enable a dramatic improvements in subsystem operability. The HRST study has examined diverse approaches, including combination propulsion systems, combined cycle propulsion, launch assist systems, and revolutionary rocket propulsion. An integrated assessment has been conducted, including both the concepts defined as part of the study as well as past concepts. This assessment suggests that the cost goals of HRST are achievable within the next 10–20 years if appropriate technology investments are pursued. This paper provides a summary report on the results and findings of the HRST study project.

Informed maintenance for next generation reusable launch systems

Perhaps the most substantial single obstacle to progress of space exploration and utilization of space for human benefit is the safety & reliability and the inherent cost of launching to, and returning from, space. The primary influence in the high costs of current launch systems (the same is true for commercial and military aircraft and most other reusable systems) is the operations, maintenance and infrastructure portion of the program's total life cycle costs. Reusable Launch Vehicle (RLV) maintenance and design have traditionally been two separate engineering disciplines with often conflicting objectives - maximizing ease of maintenance versus optimizing performance, size and cost. Testability analysis, an element of Informed Maintenance (IM), has been an ad hoc, manual effort, in which maintenance engineers attempt to identify an efficient method of troubleshooting for the given product, with little or no control over product design. Therefore, testability deficiencies in the design cannot be rectified. It is now widely recognized that IM must be engineered into the product at the design stage itself, so that an optimal compromise is achieved between system maintainability and performance. The elements of IM include testability analysis, diagnostics/prognostics, automated maintenance scheduling, automated logistics coordination, paperless documentation and data mining. IM derives its heritage from complimentary NASA science, space and aeronautic enterprises such as the on-board autonomous Remote Agent Architecture recently flown on NASA's Deep Space 1 Probe as well as commercial industries that employ quick turnaround operations. Commercial technologies and processes supporting NASA's IM initiatives include condition based maintenance technologies from Boeing's Commercial 777 Aircraft and Lockheed-Martin's F-22 Fighter, automotive computer diagnostics and autonomous controllers that enable 100,000 mile maintenance free operations, and locomotive monitoring system software. This paper will summarize NASA's long-term strategy, development, and implementation plans for Informed Maintenance for next generation RLVs. This will be done through a convergence into a single IM vision the work being performed throughout NASA, industry and academia. Additionally, a current status of IM development throughout NASA programs such as the Space Shuttle, X-33, X-34 and X-37 will be provided and will conclude with an overview of near-term work that is being initiated in FY00 to support NASA's 2 nd Generation Reusable Launch Vehicle Program.

The reusable launch vehicle program: Financing the reusable launch vehicle

The reusable launch vehicle program: Financing the reusable launch vehicle

Single-stage-to-orbit — A step closer

Over the past several years there has been a significant effort within the United States to assess options to replace the Space Shuttle some time after the turn of the century. In order to provide a range of technology options, a wide variety of vehicle types and propulsion systems have been examined. These vehicle concepts which are representative of the classes of concepts mat could be proposed for any future vehicle development is being used in the initial phase of the access to space activity to identify requirements for the technology maturation effort and to assess approaches to achieve the required low operations cost. This paper provides the results of recent systems analyses and describes the ongoing technology maturation and demonstration program supporting the Reusable Launch Vehicle Program.