How to open OLC flight tracks in SeeYou
and view them on a TherMap backdrop

SeeYou is the most popular software for analyzing and viewing flight records of glider flights. Having paid a licence fee one can activate the software downloaded from the Internet. Separate versions for personal computers as well as mobile devices are available.

SeeYou can open the flight record in IGC as well as LXN format and then save them in either IGC, MUL, BMP, OLC or JPG format, thereby working also as a format converter. However SeeYou does not offer conversions to the KML format of Google Earth. Users interested to do that are advised to read the instructions for analyzing flights with Google Earth.

1. Viewing a flight in SeeYou

Users having installed SeeYou can open an IGC or LXN flight record file, or after having downloaded it from OLC, to view the flight typically as shown in the figure below. This example contains the track of a flight coming from the north, before crossing a large valley and then regaining altitude and continuing across the side valleys further south. Here, the color of the flight track has been selected to be the variometer reading. SeeYou actually offers 15 different possibilities for colouring the flight track, which is a real advantage. Due to the variometer color coding one can easily see how the pilot has been regaining altitude after having crossed the main valley.

SeeYou also permits to view flights in 3D. In this case one can see not only the actual flight track, but also the ground trace showing exactly the locations over which the glider has been flying.

The next figure shows a 3D-view of the same flight. Due to the added 3rd dimension one can now perceive even better how the glider has been gaining altitude after crossing the main valley. However the terrain shown here is what SeeYou offers as a vector map, a kind of minimum surface representation. It is therefore relatively difficult to interpret the terrain itself.

SeeYou offers also the use of more detailed Raster Maps derived from satellite pictures. However, although the latter show more surface detail, they hardly provide further insights on thermal processes linked with the landscape. This is where TherMap can provide further insights.

2. Adding TherMap backdrops to SeeYou

  1. Open SeeYou with the flight you want to analyze and decide on the region, date and daytime you want to use as a TherMap backdrop. Note the coordinates of the NW and SE corner of the backdrop map (you find them under "Regions available" on the webpage).

  2. Download this map from the TherMap site, using the "View/Download Maps" item in the TherMap menu, and note the name of the folder where you store it.

  3. In SeeYou: Select >Tools >Rastermaps > Add and then select and open the map you have just downloaded

  4. Complete the file indications for this map (below the SeeYou table of maps):
    • Under "Caption" add the map name you want to use in See You,
    • Declare the "Map Group" as: "Other maps",
    • The field "Licence" can be left empty,
    • Under "Priority" you shift the slider to "high", and
    • Make sure the "map" and the "group" checkbox are switched to "active"

  5. Click on "Calibrate", enter the NW and SE corner coordinates of the map, as noted under point 1, and press "OK" to return.

  6. Select "Convert" and
    • Make sure the box indicating that the source file can be deleted is unticked, unless you are sure you do not need it again
    • Press the "Start" button to launch the conversion of the JPG file into a CMR file.
    • When the conversion is finished press "Close" to return.

  7. The map file list now contains the converted CMR file.
    • Make sure the "map" and the "group" checkbox are still switched to "active"
    • Press "OK" to return to the SeeYou main screen

  8. Activate the TherMap backdrop by
    • Opening >Tools > Options, and click on the "Rastermaps" box.
    • (Note: If this box is already on, switch it off and press "OK" to return to main screen. Then redo point 8 again, to make sure this time the new rastermap is also included).
    • Then press "OK" to return to main screen.

  9. The TherMap overlay should now immediately appear on the SeeYou screen!
    • If not, zoom in or out, to unblock it, if needed.
    • If this does not work, repeat steps 3 to 9, to make sure you have not skipped one of the above steps


SeeYou then displays the flight on the selected TherMap backdrop, as shown on the following figure. Since TherMap is a color map, the color coded flight track does not contrast well. The example below nevertheless demonstrates a high correlation between the thermal potential of TherMap and the actual variometer readings of the flight track.

In the 3D-view the ground trace crossing hotspot areas usually shows high variometer readings, thus illustrating once again the validity of the TherMap model.

By changing the color coding parameter of the flight track, it is possible to obtain a better contrast, as illustrated in the following figure in which the flight track has been color coded by the altitude.

The original SeeYou user guide can be downloaded in different languages. See >Tools>Rastermaps for more. These manuals also elaborate on the different procedures and map types.


Congratulations !