package body Aspect1_Horizontal is
   function Theta_D(s: Position_2d_Pkg.Vect2; nzv: Speed_2d_Pkg.Nz_vect2)
      return float
   is
        a: constant float := 0.0;
   begin
      return 0.0;
   end Theta_D;
end Aspect1_Horizontal;