CCAS (pronounced /ciːkæs/; CEE-kas) is an aircraft collision avoidance system, especially used by VFR pilots. CCAS operates in lower airspaces, depending on the terrain from ground level up to 5,000 ft AGL.

- How it works -

Each CCAS client periodically sends its own position to the CCAS network. On the other hand, the CCAS servers broadcast all relevant traffic around this position back to the CCAS client. By using standard TCP connections combined with a highly optimized protocol, this operates almost in real-time.

Besides other CCAS users, the server also broadcasts traffic information from different other sources, such as ADS-B, as well as OGN/FLARM, in order to have as much information as possible.

You can easily connect CCAS to your navigation app (e.g. VFRnav). This means that traffic is displayed directly on the moving map. Traffic data is transmitted via GDL90. In addition, CCAS can be used as a proxy for other traffic data sources such as Stratux, FLARM or ADS-B receivers.

- How to use -

In order to use CCAS and help increase safety in the air, simply download the official CCAS client. It's completely free by the way!

Important note on privacy: No registration is necessary. Upon the first launch of the client, a random ID is generated on the device. Every position message is sent encrypted and only provided to other users of CCAS network in immediate proximity. No flight history is saved.

- How to contribute -

Simply use the client. Every pilot using CCAS makes an important contribution to make the airspace safe.