I have been flying a P3S for over 2 years, with over 150 flights logged. On 2-24-2018 I had a simple POI flight around the house, at the end I decided to test RTH from a distance of only 290'. The AC ascended to RTH altitude of 60m, cruised home and landed as advertised. I had initiated RTH in the past with success, but usually retake control to descend and hand catch the bird.
The next day I made a (bad) decision to fly in marginal conditions, with NWS local Mesonet data showing wind gusts of 15 MPH. I live in a heavily wooded area so it is hard to measure actual wind speeds. I ascended to 400 feet and the drone was maintaining position without much trouble, so I decided to fly almost directly upwind to an area I wanted to video, figuring that it was safer to fly upwind as it would be no problem flying back downwind. During the flight, the wind increased (I estimate that the wind was close to 20mph with higher gusts at 400+feet altitude), and I decided to bring the drone back. I initiated RTH from the GO APP with the drone 935' from home with good video and RC signals. It came back to within 35' of home and initiated auto landing. At this point it was still at 400+ feet altitude, but started to drift downwind and was down to 120' altitude (many trees in this area are over 110 feet!), now 360' from home point, and still trying to auto land out in the woods. I used the joystick to gain altitude, but as soon as I released the stick, it would start to rapidly descend again. I was sweating big time as I could see the tops of the trees on the video download, and I would lose visual on the drone behind the trees! I do not know if it was attempting to cruise back to home point, but data shows GPS still working with 9 satellites. I cancelled the landing, ascended to 220 feet and flew back home and landed manually, to my immense relief.
Ok. So I get back in and look at the harrowing video (tops of trees waving in my face maybe 15 feet away!) and the flight record data. I was getting "strong interference detected" warnings at various times, but this has been usual since about 3 firmware updates back, and I've not previously seen any ill effects. So the questions are: Why would the RTH logic attempt to auto land the AC 360' the from the home point? Did the wind cause the failure? Is there some flaw/limitation in the RTH algorithm logic? Should RTH not be used in windy conditions?
The next day I made a (bad) decision to fly in marginal conditions, with NWS local Mesonet data showing wind gusts of 15 MPH. I live in a heavily wooded area so it is hard to measure actual wind speeds. I ascended to 400 feet and the drone was maintaining position without much trouble, so I decided to fly almost directly upwind to an area I wanted to video, figuring that it was safer to fly upwind as it would be no problem flying back downwind. During the flight, the wind increased (I estimate that the wind was close to 20mph with higher gusts at 400+feet altitude), and I decided to bring the drone back. I initiated RTH from the GO APP with the drone 935' from home with good video and RC signals. It came back to within 35' of home and initiated auto landing. At this point it was still at 400+ feet altitude, but started to drift downwind and was down to 120' altitude (many trees in this area are over 110 feet!), now 360' from home point, and still trying to auto land out in the woods. I used the joystick to gain altitude, but as soon as I released the stick, it would start to rapidly descend again. I was sweating big time as I could see the tops of the trees on the video download, and I would lose visual on the drone behind the trees! I do not know if it was attempting to cruise back to home point, but data shows GPS still working with 9 satellites. I cancelled the landing, ascended to 220 feet and flew back home and landed manually, to my immense relief.
Ok. So I get back in and look at the harrowing video (tops of trees waving in my face maybe 15 feet away!) and the flight record data. I was getting "strong interference detected" warnings at various times, but this has been usual since about 3 firmware updates back, and I've not previously seen any ill effects. So the questions are: Why would the RTH logic attempt to auto land the AC 360' the from the home point? Did the wind cause the failure? Is there some flaw/limitation in the RTH algorithm logic? Should RTH not be used in windy conditions?
