A profile is defined by a profile name, an optional description and a 3-dimensional pointlist with all three coordinates mandatory. For typical profiles, one of the coordinate vectors contains only "0" entries. All point coordinates are transferred to the global coordinate system. The points have to be ordered in a mathematical positive sense. Normalized coordinates are not required. First and last point may, but need not to, be identical. Hence, it is possible to include "open" profiles. However, the trailing edge position of the upper and lower point need to be identical. No crooked trailing edges are possible.

Example 1: For a conventional wing, the airfoil coordinates are defined in x and z with all the y-coordinates set to "0". The points have to be ordered from the trailing edge along the lower side to the leading edge and then along the upper side back to the trailing edge.

Example 2: For a fuselage, the coordinates are typically given in y and z with x set to "0". Starting point of the profile should be the lowest point (typically in the symmetry plane), then upwards on the positive y-side up to the highest point (again, typically in the symmetry plane). Depending on, whether the fuselage shall be specified with symmetry condition or not, the profile either ends there, or continues on the negative y-side back down to the lowest point.

Alternatively, it is possible to specify the coordinates of a profile via the CST (class function /shape function transformation technique) notation. Please see the cst2DType for further information.

A profile can be symmetric. In that case the profile is interpreted as being not closed and will be closed by mirroring it on the symmetry plane.

Reference