Some ADS-B planes have "No callsign", but if you look 40 miles behind them (in the US) you can often find the plane from FAA data.
![](https://www.metabunk.org/sk/Flightradar24.com__Live_flight_tracker_20140316_123159_20140316_123205__100_Layer_1_RGB8__20140316_123302_20140316_124000.jpg)
Notice the different photos. The ADS-B data has the callsign, so they use a photo of the actual plane. The FAA data does not have the callsign, so is using a generic image of a 737
![](https://www.metabunk.org/sk/Flightradar24.com__Live_flight_tracker_20140316_123159_20140316_123205__100_Layer_1_RGB8__20140316_123302_20140316_124000.jpg)
Notice the different photos. The ADS-B data has the callsign, so they use a photo of the actual plane. The FAA data does not have the callsign, so is using a generic image of a 737