Most of us take our transponders for granted. That little box offers eight values in each of four digits. Multiplying 8×8×8 ×8, you get 4096 possible codes. There are about 9,100 aircraft airborne reported by FlightAware as this is being written. Do you see a problem? Unfortunately discrete codes are not altogether discrete, meaning that national management is required to keep aircraft in the same area from being given the same squawk.
展开▼
