FoW Scan MAX range
 

Cannot seem to get this function to work. It seem the enemy's aircraft position on the map will only show when the enemy plane is spotted within only 2km or less from the specified recon aircraft.
Set the Scan MAX range to differing values, 8km, 12km, 20km, as high as 40km, no change in results than from the default 2Km Scan MAX range.
So what am I doing wrong?
Attached are 2 missions where I've experimented with this.