Frank wrote:
NEC will calculate "Space wave plus surface wave" if required.

Frank
Have you tried doing this calculation with a horizontally polarized VHF
antenna? What did you find?

Roy Lewallen, W7EL

As an example I tried the following:

CM Horizontal Dipole
CE
GW 1 11 0 0 3 0 1.5 3 0.01
GE 1 -1 0
GN 2 0 0 0 13.0000 0.0050
FR 0 1 0 0 100 1
EX 0 1 6 0 1 0
RP 1 1 360 0000 3 0 1.00000 1.00000 10000
EN

At 10,000 meters, 3 meters off the ground:
E(theta) is maximum off the ends at 3.5E-8 V/m
E(phi) is maximum off the sides at 2.6E-7 V/m

This agrees with the expected horizontal polarization off
the sides, and vertical polarization off the ends.

Frank, VE6CB

Now what's the result without the surface wave?

Roy Lewallen, W7EL