A 3.5-year effort to characterize the aerodynamic behavior of the Ares I-X Flight Test Vehicle (AIX FTV) is described in this paper. The AIX FTV was designed to be representative of the Ares I Crew Launch Vehicle (CLV). While there are several differences in the outer mold line from the current revision of the CLV, the overall length, mass distribution, and flight systems of the two vehicles are very similar. This paper briefly touches on each of the aerodynamic databases developed in the program, describing the methodology employed, experimental and computational contributions to the generation of the databases, and how well the databases and underlying computations compare to actual flight test results.

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A modified profile optimization method using a smoothest shape modification strategy (POSSEM) is developed for airfoil shape optimization in a preliminary design environment. POSSEM is formulated to overcome two technical difficulties frequently encountered when conducting multipoint airfoil optimization within a high-resolution design space: the generation of undesirable optimal airfoil shapes due to high frequency components in the parametric geometry model and significant degradation in the off-design performance. To demonstrate the usefulness of POSSEM in a preliminary design environment, a design competition was conducted with the objective of improving a fairly well-designed baseline airfoil at four transonic flight conditions without incurring any off-design performance degradation. Independently, two designs were generated from the inverse design tool CDISC, while a third design was generated from POSSEM using over 200 control points of a cubic B-spline curve representation of the airfoil as design variables for the shape optimization. Pros and cons of all the airfoil designs are documented along with in-depth analyses of simulation results. The POSSEM design exhibits a fairly smooth curvature and no degradation in the off-design performance. Moreover, it has the lowest average drag among the three designs at the design conditions, as evaluated from three different flow solvers. This study demonstrates the potential of POSSEM as a practical airfoil optimization tool for use in a preliminary design environment. The novel ideas used in POSSEM, such as the smoothest shape modification and modified profile optimization strategies, are applicable to minimizing aircraft drag at multiple flight conditions. This material is declared a work of the U.S. Government and is not subject to copyright protection in the United States.

A modified profile optimization method using a smoothest shape modification strategy (POSSEM) is developed for airfoil shape optimization in a preliminary design environment. POSSEM is formulated to overcome two technical difficulties frequently encountered when conducting multipoint airfoil optimization within a high-resolution design space: the generation of undesirable optimal airfoil shapes due to high frequency components in the parametric geometry model and significant degradation in the off-design performance. To demonstrate the usefulness of POSSEM in a preliminary design environment, a design competition was conducted with the objective of improving a fairly well-designed baseline airfoil at four transonic flight conditions without incurring any off-design performance degradation. Independently, two designs were generated from the inverse design tool CDISC, while a third design was generated from POSSEM using over 200 control points of a cubic B-spline curve representation of the airfoil as design variables for the shape optimization. Pros and cons of all the airfoil designs are documented along with in-depth analyses of simulation results. The POSSEM design exhibits a fairly smooth curvature and no degradation in the off-design performance. Moreover, it has the lowest average drag among the three designs at the design conditions, as evaluated from three different flow solvers. This study demonstrates the potential of POSSEM as a practical airfoil optimization tool for use in a preliminary design environment. The novel ideas used in POSSEM, such as the smoothest shape modification and modified profile optimization strategies, are applicable to minimizing aircraft drag at multiple flight conditions. This material is declared a work of the U.S. Government and is not subject to copyright protection in the United States.