Warning: geeky! I noticed something very odd at the weekend and wonder if anyone can explain it.
I was using
www.glideandseek.com to monitor a friend’s flight from the south of the UK to Le Mans (France). GlideandSeek displays data from the Open Glider Network, to which PAW groundstations contribute data, making PAW users visible in addition to the FLARM users. My friend has a PAW Classsic without airborne internet connectivity.
He was tracked perfectly to about mid-channel and then disappeared. I believe there are very few PAW groundstations outside the UK so at first sight this might be expected but I understand that “normal” OGN stations without the PAW hardware added (the vast majority of those outside the UK) should also receive PAW as well as their native FLARM using their SDR dongles. A bit of research however showed that this OGN receiver functionality reportedly does not currently work. So the loss of tracking outside the UK still made some sense.
Now (finally!) here’s the interesting bit. I later checked the flight in the PAW database using the PAW Groundstation replay facility which I think is now quite well known. At first sight the same happened: perfect tracking but only to mid-channel. However looking more carefully, there are individual track points logged every 2 minutes all the way to the destination. You have to look very carefully to spot the individual red dots.
I can’t figure out how this is happening. I don’t believe there is PAW groundstation coverage all along this route and if there was then surely there would be a normal complete track. I also don’t believe there can be any air to air relaying going on and there is no internet connectivity. The only other option is that the OGN stations are in fact receiving PAW equipped aircaft and PAW are importing this data back into their own system which I didn't think they did. But in that case why would GlideAndSeek not display this same intermittent data, and why is it intermittent?
Hope this isn’t too garbled. Can anyone shed any light on what’s happening please?
Alan