Although that is technically true it is deceptive at the same time. The 2 meter band of 144 to 148 MHz does bend slightly back toward the earth and is at least a little long of line of sight. That effect is much more pronounced were the original signal passes over the top of a sharp ridge and similar ground features. The 6 meter band of 50 to 54 MHz; which is still considered VHF; shares some of the propagation characteristics of the 2 meter band while at the same time having some of the characteristics of the 10 Meter High Frequency Band of 28 to 29.7 KHz. The portable radios most readily available to ordinary radio users are indeed line of sight though.
On the other hand High frequency radios, that use frequencies between 3 and 30 KHz, have ranges that can be very different depending on the height of the antenna used above local ground level. Between 1/10th and 1/4 Wavelength above the ground High Frequency radio waves go essentially straight up from horizontally polarized antennas. Frequencies at the lower end of the High Frequency bands tend to reflect off of the Ionosphere and come back to earth in a limited diameter circle around the antenna site. Antennas which are 1/4 wavelength and more above the earth tend to throw their energy out at a much lower angle were it can reflect off of the Ionosphere and return to earth at quite long distances from the antenna. The area between the site of the antenna and the next area were that signal returns to earth is called the Skip Zone in that the signal skips the area in between and cannot be copied there. The 11 meter Citizens Band is subject to that second effect but it's actual range is very much dependent on the condition of the Ionosphere. 11 Meter signals will tend to be absorbed by the Ionosphere except when the Ionosphere is very highly charged.
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TatkinsH
