Light Transport; Low Wing; 2 Turbojet Eng
Flight Crew Air Transport Pilot (ATP)
ATC Issue All Types; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Other / Unknown
Flight Crew Took Evasive Action
ATC Equipment / Nav Facility / Buildings
Miami center cleared us to 7000 ft approximately 50 miles from MYAM then to 3000 ft. We were told to contact Nassau approach on 121.0. We could not get in contact with them so we tried to switch back to Miami approximately 25 miles from MYAM and we could hear Miami center but they could not hear us. They tried to relay messages thru another aircraft in the area but communications were not clear. We were never given clearance instructions in the event of a missed approach before we lost communications with Miami. We were not able to communicate with Nassau approach or Nassau radio at 3000 ft. We never saw the field at 3000 ft when we overflew the field. We heard another aircraft departing from MYAM and we showed him on our TCAS. We proceeded to climb in a holding pattern VFR to 7500 to avoid the departing traffic that was on the TCAS; so that we could establish communications with Miami and tell them we were diverting to our alternate. When we got in radio contact with Miami they asked us who gave us a clearance to climb. I replied that we were climbing VFR for traffic and to establish communications. Miami asked what our intentions were and I told them we were diverting to MYGF. Miami then told me to maintain 8000 and proceed to GRREG intersection and then MYGF. We were handed off to Nassau approach and we then landed at MYGF.Our feasibility notes on our brief tell us that there is no radar below 7000 and communications are intermittent below 7000 and if communications are lost contact Nassau approach on 121.0 to cancel IFR or handle the diversion if unable to land visually. We could not get in contact with Nassau approach on 121.0 at 3000 ft.We were told that Miami could not give us missed approach instructions. We would get them from Nassau approach. When we were given the frequency change we could not contact Nassau approach and when we switched back to Miami we could not talk to Miami either.
Light Transport flight crew reported experiencing communication issues with Miami Center and Nassau Approach. Flight crew elected to divert due to departing traffic from the original destination and the inability of the ZMA Controller to give them a missed approach clearance.