Mode S transponders used in aviation need a unique address managed by the authority in each state. In Finland, an aircraft is given its own Mode S address, i.e. an ICAO 24-bit address, in connection with the registration. However, if the Mode S transponder is used for some other purpose than in the registered aircraft, for example in a land vehicle, an unregistered glider or a drone, a separate address is needed. With this service you can apply for a separate address for a Mode S transponder
The Mode S address can be expressed in, for example, binary or hexadecimal format (hex code). The codes determined for aircraft registered in the Finnish Transport Register can be found in the aircraft registration documents. You can also find the code determined for the aircraft in the https://www.traficom.fi/en/services/register-data-aircraft (External link) based on the aircraft registration mark.
There is an annual fee collected for the administration of the registry.