uAvionix has decided to not use Mode C because it cannot deliver adequate performance :

  • SkyEcho has an omnidirectional antenna- hence no azimuth detection is possible
  • The use of signal strength is unreliable as a distance measure
  • Mode C transponders don’t transmit unless triggered by a ground radar or TCAS.  This doesn’t happen in many parts of Australia or even at low altitudes below ATC radar coverage.