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Traffic Alert and Collision Avoidance System

The initial implementation of TCAS is available in the development and experimental branch at this time. Please note details about this system and it's functions will come at a later time.

Our TCAS supports online network traffic services (Vatsim / IVAO).

TCAS Known Issues

  • No support for offline AI traffic (sim limitation)
  • No support of multiplayer (MSFS) traffic (sim limitation)
  • Possible false detection of ground traffic
  • Possible ghost TA / RA due to jumping traffic (improvements and changes expected)

A Quick Note on TCAS Performance

TCAS relative altitude is now based on plane altitude (true altitude) for both airplanes. This should work exactly as intended for MSFS airplanes relative to one another (though not as the IRL TCAS works). It can still be somewhat of an issue when on a network with non-MSFS airplanes.

The reason for this is that MSFS is the only sim that should correctly compute the true altitude. Depending on the atmospheric conditions, an MSFS airplane flying in the same weather and with the same baro setting as a non-MSFS airplane may be at a different true altitude than the non-MSFS airplane. Said differently, each aircraft could be at the same altitude in their respective simulator, but TCAS would show them at different altitudes.

This is not just a TCAS issue. It is an issue that VATSIM and all the other networks are struggling with so that ATC sees all airplanes, regardless of sim, at the right altitudes, at least relative to one another.


Last update: March 10, 2022
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