ArduCopter 4.0.3, crash in loiter mode, Pixhawk 2.4.8 + Radiolink SE100

Hello everyone, please help to understand the reasons for the crash of my hexacopter, thank you very much for your help.

What happened:
I armed and flew in loiter mode, 2-3 m. above ground, to check if everything is fine,
i land, then took off again in loiter mode, put on my FPV glasses and at that moment the copter was blown away from me, telemetry at that moment said something about ekf and gps.

You lost GPS in flight. Perhaps a faulty wiring or interference.

Thanks for the quick reply, I thought so.
Since I was launching another of my copter in the same place, I think there were no interferences, it flew perfectly.
Is it possible to find out more precisely the reason, how do I check the quality of the GPS connection, is there any documentation / instructions on what to do in this situation on the pixhawk board?

Also the question, will the installation of second GPS module help to avoid such a situation in the future?

It is very likely a faulty module. It lost sats during the first flight as well, but only momentary. As I see GPS kept communicating with the FC, so it is not a wiring problem. Based on the fields in UBX1 and UBX2 it looks like a total freeze of the RF frontend in the module.

Also not likely related, but the FC power voltage is way to low (4.8-4,7Volt) It should be around 5.3Volt.

The only course of action in these situations to switch to AltHold (or stab) mode and steer the copter. (it actually happened automatically but too late)
Also a second GPS definitely helps to mitigate such situations.

So I will install the second GPS module, I will also see why such a low supply voltage of the flight controller, thank you very much for your help)

For information, my gps module is Radiolink SE100 (M8N GPS) and pixhawk 2.4.8 clone.

What you get is what you paid for, a radiolink SE100 is 25usd, a decent real Ublox-m8m costs around 60$…

I think radio link SE100 gps module it’s good for me because it’s cheaper also no more waiting to capture satellite number , only 20 to max 40s to capture 15+ satellite (trying on more then 10 places) so I’m happy with this module , do you have any more options to switch module with se100?

Thank you , happy flying :slightly_smiling_face:

I agree with you, I have a GPS RadioLink SE100 and it works perfectly for me, in fact it is faster acquiring satellites than other more expensive modules, I do not want to mention the brands, but I had to spend a lot of money before discovering the GPS RadioLink … …

On my other copter there is a Radiolink TS100, more than 10 flights, there were no problems with it, so I assume that either my SE100 is buggy and does not work properly or still the quality of contacts and power supply, which I will fix, will be able to start it , let’s see after the tests, thank you all for the feedback, good luck)