Sense and avoid¶
Midair collisions are a major reason for loss of lives in general aviation. Collisions often happen near airfields or in the traffic circuit. In order to enhance security, Enroute Flight Navigation can connect to your aircraft’s traffic receiver (typically a FLARM device) and display nearby traffic on the moving map.
The figure Approaching EDTF with traffic shows what to expect. The figure shows two traffic factors.
There is one aircraft in the downwind section of the traffic circuit. The traffic has approximately the same altitude as the own aircraft and is sinking. The green color indicates “no alarm”.
There is one aircraft nearby whose precise position is unknown to the traffic receiver; this is often the case with traffic that has only a Mode-S transponder. The traffic is most likely found within the yellow circle. The yellow color indicates that the traffic might be close enough to be dangerous.
To show only relevant traffic, Enroute Flight Navigation will display traffic factors only if the vertical distance is less than 1.500m and the horizontal distance less than 20nm.
Enroute Flight Navigation shows traffic on the moving map, but does not issue traffic warnings. The app contains no collision avoidance algorithms. Color coding of traffic according to relevance works best with FLARM devices.
Enroute Flight Navigation should work with all modern, standard-compliant traffic receivers. The author has tested the app with the following receivers.
Users reported success with the following traffic receivers.
Most traffic data receivers can only handle one concurrent connection. If more devices connect, this might lead to frequent loss of connection or loss of data. To be on the safe side, it might be useful to ask your passengers to disable Wi-Fi on their phone before boarding.
For best results, use FLARM compatible devices. If your traffic receiver supports FLARM/NMEA as well as GDL90 output, always use FLARM/NMEA. The GDL90 protocol has a number of shortcomings that Enroute Flight Navigation cannot always work around. See the Section Known issues with GDL90 for more details.
Before you connect¶
Before you try to connect this app to your traffic receiver, make sure that the following conditions are met.
Your traffic receiver has an integrated Wi-Fi interface that acts as a wireless access point. Bluetooth devices are currently not supported.
You know the network name (=SSID) of the Wi-Fi network deployed by your traffic receiver. If the network is encrypted, you also need to know the Wi-Fi password.
Some devices require an additional password in order to access traffic data. If this is the case, you will need to know this password.
Connect to the traffic receiver¶
It takes two steps to connect Enroute Flight Navigation to the traffic receiver for the first time. Once things are set up properly, your device should automatically detect the traffic receiver’s Wi-Fi network, enter the network and connect to the traffic data stream whenever you go flying.
Step 1: Enter the traffic receiver’s Wi-Fi network¶
Make sure that the traffic receiver has power and is switched on. In a typical aircraft installation, the traffic receiver is connected to the ‘Avionics’ switch and will automatically switch on. You may need to wait a minute before the Wi-Fi comes online and is visible to your device.
Enter the Wi-Fi network deployed by your traffic receiver. This is usually done in the “Wi-Fi Settings” of your device. Enter the Wi-Fi password if required. Some devices will issue a warning that the Wi-Fi is not connected to the internet. In this case, you might need to confirm that you wish to enter the Wi-Fi network.
Most operating systems will offer to remember the connection, so that your device will automatically connect to this Wi-Fi in the future. We recommend using this option.
Step 2: Connect to the traffic data stream¶
Open the main menu and navigate to the “Information” menu.
If the entry “Traffic Receiver” is highlighted in green, then Enroute Flight Navigation has already found the traffic receiver in the network and has connected to it. Congratulations, you are done!
If the entry “Traffic Receiver” is not highlighted in green, then select the entry. The “Traffic Receiver Status” page will open. The page explains the connection status in detail, and explains how to establish a connection manually.
Enroute Flight Navigation is able to use the database from Flarmnet.org to identify aircraft and to show the aircraft registration in the moving map display. The process does not require user interaction: once the app connects to a FLARM device and receives traffic information, the Flarmnet database will automatically be downloaded and updated with every map update. If desired, the database can also be downloaded manually on the page “Maps and Data” (open the main menu and go to “Library/Maps and Data”).
The app cannot connect to the traffic data stream.
Check that your device is connected to the Wi-Fi network deployed by your traffic receiver.
The connection breaks down after a few seconds.
Most traffic receivers cannot serve more than one client and abort connections at random if more than one device tries to access.
Make sure that there no second device connected to the traffic receiver’s Wi-Fi network. The other device might well be in your friend’s pocket!
Make sure that there is no other app trying to connect to the traffic receiver’s data stream.
Many traffic receivers offer “configuration panels” that can be accessed via a web browser. Close all web browsers.