Mode S

We have been required for years to use both a Transponder and Encoder in controlled airspace.  This combination allows altitude reporting to ATC, and is known as "Mode C" operation.  "Mode S" is the next step.  A Mode S transponder (which still requires an Encoder for altitude information) transmits aircraft-specific identifying information to ATC.  You might want to provide Mode S information to ATC or you might be required to do so as part of a Commercial operation.  Mode S operation is also required in Europe.

Please note that while Mode S is helpful, it does not meet the ADS-B 2020 mandate by itself.  However, some Mode S Transponders with Extended Squitter can be used as a building block in an ADS-B system.

If you are looking for a Mode S Transponder that is not listed here, please click to send us an email. If we don't have it in stock, we can find it for you!