U.S. Supersonic Commercial Aircraft Assessing NASA's High Speed Research Program (1997) / Chapter Skim
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6 SUMMARY OF PROGRAM PLANNING ISSUES
6 SUMMARY OF PROGRAM PLANNING ISSUES
Pages 110-126
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From page 110... ...
By 2002, the program will have resolved many foundational questions regarding the technical feasibility of producing an economically viable HSCT. Furthermore, the committee believes that Phase II will produce an important, broadly applicable technological legacy regardless of industry's decision about proceeding with commercial development of an HSCT.
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From page 111... ...
Vision Statement As noted in Chapters 1 and 2, the committee views the HSR Program's vision statement as over-specified and unattainable by the current program plan.
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From page 112... ...
Although the timetable and performance requirements help to focus technology development, the committee believes they increase overall program risk by threatening the ability to achieve the most important objectives environmental acceptability and economic viability. For example, a cruise speed of Mach 2.4 provides some operational advantages over lower speeds, such as Mach 2.0 or 2.2.
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From page 113... ...
To make efficient use of available funding, Phase II should be adjusted as described above, even if the recommended technology maturation and advanced technology demonstration phases are not implemented. The committee does not believe that Phase II alone can achieve the program's current goals regardless of how it is structured.
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From page 114... ...
Providing the resources necessary to integrate and test two full-scale demonstrator engines is essential, even if this means lowering the TRL goals for some lower priority and lower risk program elements. Advanced Technology Demonstration Phase The technical difficulty of building an economically viable HSCT is similar in magnitude to the difficulty of developing the advanced reusable launch vehicles currently envisioned by NASA.
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From page 115... ...
Currently, the program concentrates on weight as the primary metric for economic viability. However, in many cases lowest weight does not equate to minimum cost, especially Industry Commitment to Advanced Preliminary Technology Industry Demonstration Commitment to Product Phase Product Launch Launch First Flight HSR Program Phase l: technology Exploration HSR Program Phase Il: Technology Developmenta HSR Program Technology Maturation Phaseb Joint effort by HSR Program and Industry Advanced Technology Demonstration PhaseC Industry Effort Product Desicin 1990 1995 2002 2006 1 ~ 2010 2014 Certification (concurrent task)
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From page 116... ...
In addition, individual airlines prefer to generate their own estimates of cost per revenue passenger mile (based on an accurate estimate of cost per available seat mile provided by the aircraft manufacturer)
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From page 117... ...
to validate the choice of metrics and their assigned TRL goals. Interdependencies The HSR Program plan does not seem to account adequately for interdependencies among the technologies and processes needed for an environmentally compatible and economically viable HSCT.
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From page 118... ...
In fact, the economic viability of the HSCT design envisioned by the HSR Program cannot be determined without an integrated materials development and manufacturing technology program. Airframe flexibility affects flight control design and handling qualities.
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From page 119... ...
PROGRAM EXECUTION This section discusses issues associated with execution of the airframe, propulsion, and integrated aircraft elements of the HSR Program. Airframe2 Full-Scale Component Tests Currently, the HSR Program plans to conduct full-scale tests of airframe and engine components using surrogate materials and surrogate manufacturing processes.
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From page 120... ...
The HSR Program should demonstrate adequate materials durability and complete the development of manufacturing technology during the recommended technology maturation phase. In particular, the HSR Program should develop test methodologies suitable for validating an airframe service life of 60,000 hours.
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From page 121... ...
Major Recommendation 9. The HSR Program should develop a more comprehensive testing and risk mitigation strategy for the combustor that extends into the recommended technology maturation phase and includes combustor testing in a full-scale demonstrator engine.
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From page 122... ...
However, the limited ability of the HSR Program (and this committee) to assess industry's internal HSCT research makes it difficult to determine the extent to which industry activities are preserving a lower cruise speed as a viable alternative.
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From page 123... ...
Thus, reserve fuel requirements that substantially change effective aircraft range could have a significant impact on the ability of the technology under development by the HSR Program to support a product launch decision. Furthermore, concerns about operational issues, such as reserve fuel requirements, will become increasingly important as the program nears the point when industry senior executives are asked to decide if the technology is ready to support development of an operational aircraft.
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From page 124... ...
The HSR Program should ensure that the flight deck system concepts under development can provide a level of safety superior to conventional systems used by subsonic transports. To ensure flight tests are successful, preliminary flight tests planned during Phase II of the HSR Program should be supplemented by additional flight tests during the proposed technology maturation and advanced technology demonstration phases.
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From page 125... ...
As the investment in HSR technologies increases, it is becoming increasingly important to ensure that certification issues do not prevent these technologies from finding useful application on a viable HSCT. Major Recommendation 16.
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