POOR           AVERAGE         EXCELLENT
Transmitter power →→→→            5w 10w 25w     5w 10w 25w       5w 10w 25w

AIRCRAFT ALTITUDE ↓↓↓↓
                   2,000 ft     -----20-----    -----40-----     -----45-----
                   5,000 ft     -----30-----    -----70-----     -----80-----
                  10,000 ft     -----50-----    ----110-----     ----120-----
                  20,000 ft       60 80 10      120 170 200       30 180 220

Table 1: Communications Ranges—Base Station to Aircraft (miles)