Initial Tower Cab Practice Test

When LLWAS data from one or more sensors isn’t arriving, the system flags a data communications issue rather than a complete loss of all data or a single sensor fault. The tower cab display shows COMM ERROR to indicate that the data feed from part of the LLWAS network is not being received properly. This distinguishes it from NO DATA (no data at all), SENSOR FAILURE (a specific hardware fault in a sensor), or COMM DOWN (the entire communication link is down). So the display indicating COMM ERROR best reflects a partial data outage from the sensor network.