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This paper outlines a comprehensive, structured, and robust methodology for decision making in the early phases ofaircraft design. The proposed approach is referred to as the Technology Identification, Evaluation, and Selection (TIES) method. The seven-step process provides the decision maker/designer with an ability to easily assess and trade-off the impact of various technologies in the absence of sophisticated, time-consuming mathematical formulations. The method also provides a framework where technically feasible alternatives can be identified with accuracy and speed. This goal is achieved through the use of various probabilistic methods, such as Response Surface Methodology and Monte Carlo Simulations. Furthermore, structured and systematic techniques are utilized to identify possible concepts and evaluation criteria by which comparisons could be made.

The ultimate goal of knowledge-based aircraft design, pilot training and flight operations is to make flight safety an inherent, built-in feature of the flight vehicle, such as its aerodynamics, strength, economics and comfort are. Individual flight accidents and incidents may vary in terms of quantitative characteristics, circumstances, and other external details. However, their cause-and-effect patterns often reveal invariant structure or essential causal chains which may re-occur in the future for the same or other vehicle types. The identification of invariant logical patterns from flight accident reports, time-histories and other data sources is very important for enhancing flight safety at the level of the ‘pilot - vehicle -operational conditions’ system. The objective of this research project was to develop and assess a method for ‘mining’ knowledge of typical cause-and-effect patterns from flight accidents and incidents.

Understanding the factors influencing crew performance under conditions of long-term isolation, confinement, high workload and elevated risk is an important prerequisite to the manned space exploration missions beyond low-Earth orbit that are planned under the new National Space Policy of the United States. Quantitatively tracking the performance of crews affected by those stressors is therefore crucial both during actual space missions and as part of precursor activities on the ground, such as those taking place at planetary-analog simulation facilities. During the summer of 2003, an experiment was carried out tracking the cognitive performance of the crew on board such a facility, the Mars Society’s “Flashline Mars Arctic Research Station” in the Canadian High Arctic. In addition to the self-administered computer-based testing, the crew’s daily activities were logged to enable the identification of external factors that might affect the observed performance.

A method to identify the topology of an aerospace system’s requirements space, specifically the location and type of the discontinuities that occur at the boundaries of the available technology and the physics of the system, allows the designer to make decisions as to the desirability of a specific solution state. Additionally, since a given set of requirements may produce multiple solutions the designer can compare his/her solution to other potential solutions. This allows an assessment of the requirements risk associated with a specific design. This paper addresses the need to visualize and understand the topology of the requirements space for a Rapid Response Strike System.

The success of business jets like the Citation X, the fastest civil aircraft in use after the Concorde, highlights the need for speed to improve business and globalization. Currently, developing a supersonic business jet has many technical and economical impediments. These obstacles include sonic boom, emissions and noise requirements problems that are easily meet or do not exist for subsonic aircraft. A baseline aircraft, defined by an optimization process, is the starting point for this study. However, this baseline aircraft does not meet the sonic boom, emissions and noise requirements, which are very strict. Companion studies to this one indicate that it may be possible to meet emissions and noise requirements, but it is clear that technology infusion is necessary for the future viability of this aircraft concept to succeed.

An evolved version of the Technology Identification, Evaluation, and Selection (TIES) method is presented that provides techniques for quantifying technological uncertainty associated with immature technologies. Uncertainty in this context implies forecasting. Forecasting the impact of immature technologies on a system is needed to provide increased knowledge to a decision-maker in the conceptual and preliminary phases of aircraft design. The increased knowledge allows for proper allocation of company resources and program management. The TIES method addresses the milestones encountered during a technology development program, the sources of uncertainty during that development, a potential method for bounding and forecasting the uncertainty, and a means to quantify the impact of any emerging technology. A proof of concept application was performed on a High Speed Civil Transport concept due to its technically challenging customer requirements.

A solid business case is highly dependent upon a strategic technology research and development plan in the early phases of product design. The embodiment of a strategic technology development plan is the identification and subsequent funding of high payoff technology programs that can maximize a company’s return on investment, which entails both performance and economic objectives. This paper describes a technique whereby the high payoff technologies may be identified across multiple platforms to quantitatively justify resource allocation decisions and investment opportunities. A proof of concept investigation was performed on a fleet of subsonic, commercial aircraft.

The accepted paradigm in aerospace systems design was to design systems sequentially and iteratively to maximize performance based on minimum weight. The traditional paradigm does not work in the rapidly changing global environment. A paradigm shift from the norm of “design for performance” to “design for affordability and quality” has been occurring in recent decades to respond to the changing global environment. Observations were made regarding new tenets needed to bridge the gap from the old to the new. These tenets include new methods and techniques for designing complex systems due to uncertainty and mulit-dimensionality, consideration of the life cycle of the system, and the methods needed to assess breakthrough technologies to meet aggressive goals of the future. The Technology Identification, Evaluation, and Selection method was proposed as a possible solution to the paradigm shift.