Super King Air 350
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 75; Flight Crew Total 13000; Flight Crew Type 600
Situational Awareness; Confusion; Communication Breakdown
ATC Issue All Types; Deviation / Discrepancy - Procedural Clearance; Ground Incursion Runway
Air Traffic Control Issued New Clearance; Air Traffic Control Provided Assistance; Flight Crew Became Reoriented; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Overcame Equipment Problem
Airport; ATC Equipment / Nav Facility / Buildings; Procedure; Weather; Staffing
Due to massive flooding in Austin the ATC system was a complete mess. The Tower was initially evacuated and the TRACON was inoperative due to being flooded. Portable tower and ground control radios were eventually brought on line but were weak and intermittent. We eventually lost contact completely with ground control and tried unsuccessfully to contact the Tower; (we had set 120.1 instead of 121.0). We then called FSS who informed us that the airport was now uncontrolled and that all ATC personnel had evacuated. We called out our taxi to other aircraft; but on the previously stated wrong frequency. After getting in line with the other airplanes on the taxiway awaiting take off; we realized our mistake and contacted Tower and told them what we had done. There was very little airplane movement on the field and no conflicts arose from our taxi out. The Tower then closed 20 minutes later and evacuated. The field was uncontrolled for the rest of the night.The FSS and tower personnel were not on the same page in regards to the field being controlled or uncontrolled status and we used the wrong tower frequency. Both of these things led to our miss communicated taxi.
Due to severe flooding in Austin Texas the TRACON was closed and the Tower was intermittently open and closed. This situation caused confusion for the pilot/reporter who began taxiing without a clearance from the Tower. The pilot contacted FSS which told them all ATC facilities had been evacuated. The flight crew had dialed the wrong ground control frequency leading them to believe the tower was not staffed. They eventually realized their mistake and contacted Ground Control.