From: NASA HQ
Posted: Saturday, May 10, 2003
Frederick D. Gregory
National Aeronautics and Space Administration
Subcommittee on Space and Aeronautics
Committee on Science
House of Representatives
Mr. Chairman and Members of the Subcommittee:
Thank you for this opportunity to appear before you and share the plans and progress we are making toward implementation of NASA's Integrated Space Transportation Plan (ISTP) and development of the Orbital Space Plane (OSP) system.
Mr. Chairman, you requested that I address a number of topics related to the ISTP and particularly the OSP Program. I will respond to these questions by first discussing the studies performed for the ISTP that led to the FY 2003 Budget Amendment submitted in November 2002. Then I will discuss the progress made toward implementation of the ISTP, and particularly the OSP Program, and, finally, I will address our approach to the reevaluation of the ISTP as a result of the Columbia tragedy.
Introduction of the New Integrated Space Transportation Plan
NASA's updated ISTP is driven by NASA's vision and mission and supported by a comprehensive series of studies and reviews that determined a more beneficial course of action for NASA, affecting many of the Agency's major programs. These budget changes reflect the interrelationship and tight coupling among the Station, Shuttle, and SLI programs to support breakthrough research in Space. They were achieved within our budget-enabling NASA's overall program to be responsible, credible, and compelling. The updated ISTP resulted in the restructuring of the SLI, and other adjustments, to accomplish the following:
Resulting budget changes reflect the interrelationship and tight coupling among the Station, Shuttle, and SLI Programs to enable humans to conduct breakthrough research in space. Achieving success in the assembly and operation of the ISS drives launch demands for the Space Shuttle, our international partners' vehicles and the OSP system. Similarly, the expected lifetime of the ISS, coupled with the potential for enhanced research and expanded crew post Core Complete, as well as our plans for future exploration goals, will drive potential future launch requirements.
The ISTP provides an integrated and systematic approach to our space transportation needs. The plan sustains the Shuttle through at least the middle of the next decade; aggressively pursues crew transport and rescue systems, called the Orbital Space Plane system; and continues the development of the technologies that will enable future launch systems. This plan allows NASA, in the near-term, to ensure that the ISS can achieve U.S. Core Complete, be ready to accommodate the International Partner modules, and better address scientific research priorities. In addition, we have established the position of the NASA Space Architect, reporting to me, to ensure our integrated approach remains consistent with NASA's vision and mission. Under the leadership of the Space Architect, NASA is aggressively studying longer-term science and exploration goals to provide further guidance that will better inform these critical decisions.
Background: Original Aim of the Space Launch Initiative
To aid in addressing our thought process in the formulation of our new ISTP, I would now like to reflect on the original aim of the Space Launch Initiative. In the late 1990's, NASA sponsored the Space Transportation Architecture Studies to examine candidate architectures for a new reusable launch vehicle and to assess the launch market outlook. Both NASA and its contractors concluded that the market was too small for industry alone to finance a new launch vehicle and thus, development would place a significant cost burden on the U.S. government. In addition, it was concluded that a two-stage-to-orbit RLV could have many desirable performance characteristics and would be within reach of existing technologies. As a result of these studies, NASA proposed the SLI, initiated in the President's FY 2001 budget. The SLI Program's stretch goals included reducing the cost of space access to $1,000 per pound to Low Earth Orbit and reducing the probability of loss of crew to 1 in 10,000 for a second generation RLV. The SLI Program planned to spend $5 billion over five years to develop critical technologies and architecture concepts that would reduce the risk of this approach, prove that these goals were attainable, and support a decision by 2005 whether or not to build an operational RLV.
This SLI Program was part of a larger investment strategy that tied together NASA's various space transportation efforts. The strategy, the original ISTP, included milestones, decision gates and off-ramps for SLI, Space Shuttle, and third-generation air-breathing hypersonic technologies. This is the ISTP that served as the basis for the original FY 2003 Budget request.
The projected government investment in SLI was based on the assumption that the development cost of a new RLV would be amortized across both the commercial and NASA launch markets. The NASA market is currently dominated by the needs of the Space Station program that requires nearly full use of the Space Shuttle. Consequently, the RLV design was driven by unique Space Station requirements that included cargo and crew transported into orbit, rendezvous and docking with the Station, and return of cargo and crew to a landing site. To ensure the safety of the crew, the new design of the RLV would be certified as human-rated.
Unfortunately, the key assumptions proved too optimistic. The commercial market continued to decline. It was premature to base new RLV requirements on other potential markets, such as DOD or future NASA exploration missions. Revised estimates of the development cost of a new RLV were well above the original estimate. Given the uncertainty of the market and the higher cost of RLV development, NASA concluded that the economic case for a new RLV was in doubt for the foreseeable future.
Options Considered for the New Integrated Space Transportation Plan
As a result, NASA decided to examine alternatives prior to making the large commitment required for full-scale development of the vehicles under study. NASA undertook an evaluation during the summer of 2002 to examine possible options for the ISTP and SLI. The options studied included:
Option 1 - Maintain the baseline ISTP program that assumed a decision in 2006, to concurrently build a new RLV two-stage booster and a crew transport vehicle to deliver crew to and from orbit. The new RLV could replace the Space Shuttle as early as 2012.
Option 2 - Develop an Orbital Space Plane system and delay the RLV Booster. This option built an OSP system by 2010-2012 to be flown on an Expendable Launch Vehicle (ELV) that would be human-rated. In this option, the RLV booster development was delayed.
Option 3 - Develop a prototype RLV booster by around 2011. This option built a common RLV prototype booster with DoD. In this option, an operational booster and Orbital Space Plane would occur later.
Option 4 - Breakthrough Technology. This option focused on long-term, high-payoff technologies, like hypersonic propulsion, and indefinitely delayed a new RLV.
The ISTP options were evaluated based on the following factors and criteria:
Safety - the potential for improved crew survivability through development of an ISS crew return vehicle and a crew escape system on a crew transport vehicle.
Assured Access - the provision of alternate independent means of meeting launch requirements despite potential launch mishaps, Space Shuttle groundings, or shortfalls in partner contributions to Station needs.
Economics - the affordability within the budget outlook and the potential for future cost savings.
Flexibility - the ability to evolve capabilities and adapt to changes in future launch requirements that remain uncertain.
These option studies were complemented by a number of other studies, including:
SLI Second Generation Reusable Launch Vehicle and Crew Transport Vehicle Development Studies, conducted by the SLI Program Office in 2002, evaluated hundreds of alternative space transportation system designs and performed in-depth evaluation of the 15 best candidates. A conclusion from these studies was that separating crew transport and cargo delivery functions would provide the optimum approach to improving crew safety and decreasing costs.
A Crew Transfer Vehicle/Crew Rescue Vehicle Study, conducted by the SLI Program in 2002, concluded that a multi-purpose Orbital Space Plane that can perform both the crew transfer and crew return functions for Station is viable and could provide the most long-term benefit for NASA's investment.
An ISTP Study by the NASA Independent Program Assessment Office in 2002 concluded that it was premature to commit to an RLV development, except that an Orbital Space Plane launched on an Expendable Launch Vehicle promised a number of benefits, including crew return from Station, assured crew access to space, potential enhanced safety for crew transfer and crew return, and a potential long-term Space Shuttle replacement strategy.
The SLI Level One Requirements effort conducted by NASA Headquarters and the SLI Program Office in 2002 indicated it was premature to commit to Level One requirements for a next-generation RLV.
The 120-Day Joint NASA/DoD Study conducted by the SLI Program Office and various Air Force organizations in 2001 - 2002 concluded there was common interest and benefit in development of the first stage of a two-stage RLV using a kerosene-fueled engine.
The National Aerospace Initiative and the National Hypersonics Plan developed by NASA and DOD in 2001 - 2003 chartered a joint NASA/DoD roadmap for technology development of an advanced space transportation system.
The Space Shuttle 2020 Study completed in 2002 concluded that the Shuttle lifetime could be extended to 2020. However, additional investments would be needed to preserve and improve Shuttle safety and maintenance beyond 2012.
Based on the criteria and information from the complementary studies, NASA chose Option 2 - Develop an Orbital Space Plane system and delay the RLV Booster. The OSP Program concept promises a number of benefits that rank well against the criteria for safety, economics, assured access and flexibility.
It is aimed at providing assured crew access to the ISS, improving crew safety, meeting the U.S. ISS crew return requirements from the ISS, and providing a bridge to the future by demonstrating technologies on a new crewed vehicle and supporting enhanced science on the Space Station. In summary, key changes to the ISTP roadmap which resulted from this decision were to extend the Shuttle lifetime from 2012 to at least the middle of the next decade and to delay the decision to develop an RLV booster from 2006 to no earlier than 2009.
The new ISTP consists of three major programs: the Shuttle, OSP, and Next Generation Launch Technology (NGLT) Programs. The OSP and NGLT Programs are both managed within the restructured Space Launch Initiative. No strategy is without risk. Some of the key risk items within the ISTP that we must address include:
Our approach to mitigating these risks is to consistently address the issues using an integrated approach within the framework of the ISTP. By pursuing multiple paths with interim decision points, we are less susceptible to technical issues and more flexible in dealing with changing requirements. We are striving to implement robustness in our design solutions and ensure that our investment strategy provides the greatest overall benefit to the Agency. The OSP program is a prime example, providing multiple benefits including assured crew access to space, meeting the U.S. commitments for crew return from the ISS, improving crew safety, and providing a bridge to the future. We believe the OSP system will, in combination with other launch systems, provide the vital human transport capability necessary to retire the Shuttle. Finally, the NASA Space Architect will ensure an integrated approach is taken to resolve any issues and remain consistent with NASA's vision and mission.
An important feature of the new ISTP is the linking of key decisions across the three space launch programs and NASA's long-term strategy. The next two years are critical for a series of decisions that will occur in the 2004 to 2005 timeframe. These decisions include: whether to compete for long-term contracts for Shuttle operations; whether to proceed into the full-scale development phase of the OSP; and whether to aggressively pursue a new launch vehicle or instead pursue a long-term technology program in pursuit of breakthrough technologies. These decisions will also be linked to the expected lifetime of the ISS, as well as any new space transportation requirements for exploration beyond low earth orbit. Currently, the ISS Program assumes Station mission life through at least the middle of next decade, and likely extending into the following decade. NASA plans to aggressively study longer-term exploration goals to provide further guidance that will better inform these critical decisions.
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