How to create a fake flightlog for UAVLogViewer?

I would like to create a fake telemetry log with pymavlink to display/plot it in UAVLogViewer - eventual goal is to convert logs from the Sensorlogger app into Mavlink tlog for viewing

I can create a log with this Python script, but it seems I am either not using the right message type(s) or am missing some required messsages to generate a bona fide flight logfile.

I can open this file in UAV Log Viewer and the fields I create are visible:

However, trying to plot say fails with ‘TypeError: Cannot read properties of undefined (reading ‘changeArray’)’

also, several of the tools under pymavlink/tools fail in reading the log, so I must be missing something

Is there a document which describes required Mavlink messages which must be present in a tlog? Do I need to create a ‘mission’?
Which dialect should I choose?

thanks for any hints.

Michael Haberler

ps: I was referred to here from

no idea on creating a fake log, but everytime you run a simulation you create a real fake log…

mission planner allows simulated missions, the .bin’s of which upload into UAVLogViewer easily.