VHF ATC Communication Band
118-136 MHz
SELCAL Range
312.6 Hz - 1479.1 Hz
SELCAL Pulse Durations
1±0.25s separated by period of 0.2±0.1s
Civil Rescue Frequency
121.5 MHz
Military Rescue Frequency
243.0 MHz
Normal ELT Emission Duration
48 hrs
Marker Beacon RF signal Frequency
75 MHz
Marker Beacon Audio Frequency
OM - 400 Hz
MM - 1300 Hz
IM - 3000 Hz
Marker Beacon Distance from Runway Threshold
OM - 4nm / 24000 ft
MM - 3500 ft
IM - 250 ft
Marker Beacon Codes
OM - _ _ _
MM - ._ ._ ._
IM - . . . .