The AIAA MDO Technical Committee has sponsored a series of 10 invited papers dealing with industry (and related) design processes, experiences, and needs. This paper presents a summary of these papers with emphasis on the needs of industry in the area of MDO. Together the 10 invited papers and this summary paper comprise an AIAA MDO Technical Committee "White Paper" on this subject. This summary paper contains; 1) a short synopsis of each paper and the industrial design it describes, 2) a sorting of all of the salient points of each of the papers into MDO categories plus a discussion of each category, and 3), a summary of industrial needs distilled from the papers. It is hoped that this summary paper will provide a technology "pull" to the MDO technology development community by presenting the industrial viewpoint on design and by reflecting industrial MDO priorities and needs.

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This paper describes a very general method for determining the steady two-dimensional potential flow about one or more bodies of arbitrary shape operating at arbitrary Froude number near a free surface. The boundary condition of zero velocity (solid wall) or prescribed velocity (suction or blowing) normal to the body surface is satisfied exactly, and the boundary condition of constant pressure on the free surface is satisfied using the classic small-wave approximation. Calculations made by the present method are compared with analytic results, other theoretical calculations and experimental data. Examples for which no comparison exists are also presented to illustrate the capability of the method.

The initial formulation of the Doublet-Lattice Method has proven theoretically accurate for calculating the interference effects on arbitrary classes of oscillating nonplanar configurations with one known exception: nearly coplanar wing/horizontal-tail combinations. For this class of problems the integration of the kernel across the element loses accuracy. The reason for this loss of accuracy is explained, and a refined method for performing the required integration is presented. Numerical studies using wing-tail configurations are presented to illustrate how well the refined method works. Also a T-tail calculation is repeated to show that calculations using other configurations are unaffected by the refinement. NomenclatureA, B, C= coefficients in parabolic approximations to kernel numerators; subscripts 1 and 2 refer to planar and nonplanar parts of kernel, respectively b r -reference semichord* is the rolling moment due to yaw of the horizontal stabilizer of Ref. 11 and Fig. 6 c -reference chord length D rs -normalwash factor; D 0rs is steady normalwash factor; D lrs and D 2rs are incremental oscillatory, planar, and nonplanar normalwash factors, respectively; D Prs is value of D lrs for z = 0 e = box semiwidth F -integral in Eq (17); F P is Mangier principal part for planar case /o = integral defined in Eq. (8) K = kernel function; KI and K 2 are factors in numerators of planar and nonplanar parts of kernel, respectively ® v (x) = modified Bessel function of argument x k r -reference reduced frequency, k r -a>b r /U M = Mach number TV= number of lifting surfaces Wj) = parabolic approximation to kernel numerator; P t and P 2 are approximations for planar and nonplanar numerators, respectively r = cylindrical radius from sending doublet S n = area of nth lifting surface S.P.( ) -denotes singular part of ( ) s = semispan T -direction cosine function; 7\ and T 2 are functions for planar and nonplanar parts of kernel, respectively, and T 2 * is modified value of T 2 U = freestream velocity #1 = parameter defined in Eq. (9) *o,y, z = Cartesian coordinate system transformed to midpoint of sending line and aligned with plane of sending box; £ is also vertical gap between near-coplanar parallel surfaces s = parameter defined in Eq. (31) y = dihedral angle \y r snd y s are dihedral angles of receiving and sending boxes, respectively, and y r = y r -y s is the relative dihedral angle between receiving and sending boxes A* s = centerline chord of sending box = spanwise coordinate, in the plane of an element = phase angle X s = sweepback angle of sending box i-chord line i/j = yaw angle to = circular frequency