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This page answers some of the most frequently asked questions about ADS-B data and its specificities.

About ADS-B#

If you want to understand the ADS-B technology better, and how it has shaped the aviation industry in the past years, we have written a series of articles about it:

ICAO address, callsign, and flight number#

Understanding the differences between the callsign and flight number can be tricky. Both will be re-used regularly and so cannot be used as unique identifiers to single out a particular flight. However, they share commonalities, such as their formatting that will often include the airline/operator code. They will sometimes look similar if not identical.

In short, Callsign is the identifier used by ATCs to distinguish different aircraft, whereas the flight number will exclusively be used by the companies and customers to identify particular flights. It is also important to know that callsigns can be reattributed by ATCs should the need arise.

ICAO addresses are unique for each aircraft, and can then be used with a lot more confidence as a unique identifier to single out a particular aircraft. It is however important to know that ICAO addresses can also change should the aircraft be assigned a new address or when a change of ownership happens.

Ingestion time VS timestamp#

The timestamp that you will see in every Spire Aviation ADS-B target update is the actual time at which the ADS-B message was picked up by our satellites or terrestrial receivers. This timestamp is always in UTC.

The ingestion time represents the time at which the ADS-B message was processed by our systems, ingested in our databases, and broadcasted in our APIs.