Communication
Handicaps in the existing systems
VHF communication limited by line of sight
HF SSB (AM) used over oceanic and remote areas
Congestion due to sharing of band with other agencies
SELCAL used due to heavy static
Intermediate HFR/T operator is provided
- May lead to distortion and delay
Teletype used for communicating with FIC (ATC) position
Propagation dependent on weather