I was explaining what a P3 did on canceling a LOC RTH. Acronym city here we go!
This is a bug that DJI-Tim? acknowledged. I think they are looking for some brave people to determine what happens after losing control for a second time. No one has stepped up. It won't be me volunteering. I am already an unpaid beta tester for their software.
Just last weekend I flew my new P3 Standard to the point of loss of control at least twice (may have been 3 times) in a single mission. Each time I cancelled RTH when she came back in range and continued flying. She has the latest firmware for the Standard.
It is a firmware issue, and apparently doesn't affect all Phantom hardware versions because they operate with differing firmware.
Yes, the Advanced and Pros. I can't find the thread for exact firmware versions, but suspect it didn't just appear in the latest.
This is a long story about how Healthy Drones saved me the cost of a new P3A. So... I have always admired the chartreuse lichens that cover a large basalt butte in central Arizona called Hickey Mountain (above, left). I've seen it hundreds of times from the road, but the climb up to it has always been daunting. The trail leading to it starts at 5011' (1528M) and climbs to 7360' (2244M), over a distance of 6300' (1920M), or an average slope of over 25%. One day, as I was passing the mountain, and realizing that I had my P3A in the trunk of the car, I decided to fly up and photograph the lichen-covered basalt. The drone climbed more than 2300' vertically as it approached the mountain top, and I got some great pictures of the lichens from an aspect previously impossible to achieve. As I was finishing the series, I noticed something I'd never noticed from the ground -- a 1000' long "spine" of lava that had squirted up from a crack and solidified west of the promontory (above middle-left). That spine was too tempting not to shoot, so I positioned the Phantom so as to get the right perspective (again, impossible to achieve before drones without a helicopter), and just as I took the third shot, the drone told me she wanted to go home (low battery warning). Since I'm used to these warnings, I cancelled the "go home" and took a few more pictures. But before I could turn the craft toward me and fly it home, I suddenly lost contact with it. I pressed the "go home" button, but it reported that the go home had failed to initiate. I pressed it again, with the same result. Then I did something silly -- I inadvertently (unknowingly?) pressed the icon on my screen that tells the drone to consider its current position "home" before I tried to initiate "go home" again. The drone never responded, and it never came back to its takeoff point.So... where's my drone? Could have been almost anywhere, depending upon what its condition was when I lost contact. The possibilities ranged from somewhere withing a 2-mile radius of where I lost contact, to somewhere along the "go home" line from there to the takeoff point to right where I lost contact. Remember, the lost-contact point is a 3-hour strenuous hike away, and it was already late afternoon -- no way to just hike up and take a look. So I came back home and started to research. This is where "Healthy Drones" comes in. I came home and downloaded the flight log using Healthy Drones (above middle-right) and pored over the data, trying to get a clue about what happened. Then I downloaded the .kml file and opened it in Google Earth (above right). I also downloaded the .csv file and started analyzing it. The Google Earth image clearly showed that the drone was descending straight down when it stopped recording data. The .csv file showed that it was descending straight down at 10' (3 M)/sec -- a fast descent, but not exactly dropping out of the sky. There was no indication of the "go home" signal or any of my attempts to initiate it, probably because by that time, contact had become intermittent.
At this point, I asked the Phantom Pilots group what they knew about go home behavior after a cancellation of the go home status, and sent them the Healthy Drones data. My impression was that the most likely place to locate the drone was immediately below where it started its fast descent. The group also felt that this was the most likely scenario, and that the drone was in an auto land mode at the time. So, as soon as I could, a few days later, I returned with a second P3A and flew the area where I suspected the drone to be. I couldn't see it on my monitor, and that was a bit disconcerting, but I came back home and started looking through the pictures. In first one, then more, I saw a tiny white speck that could have been a drone, then there were several shots that, when viewed at 100%, clearly showed the P3! (bottom left, above) What a relief! It was exactly where we thought -- directly below its last point of contact.
It took us a few days before we had time to make the 7-hour round trip hike, and to work up the energy to make such a steep and long climb, but we did it yesterday, and retrieved the drone. It as sitting sideways in a large Mountain Mahogany bush (see above, bottom right). The only visible damage was that one of the props had a broken tip! The bush was the perfect place for a soft landing! I brought it home, and with some trepidation changed the prop and inserted a fresh battery and started it up. All seemed normal. I took off and hovered, then slowly put it through its paces - took stills and video, did some autonomous flight. It flew absolutely normally! What a giant relief!
So, the point of this is to thank the Healthy Drones team for producing such a useful and easy to use program. It literally saved my $800. Without the data that Healthy Drones made available and without the utility of .kml and .csv files, I likely would have chalked this one up to experience. Also, to all the people who helped from Phantom Pilots, Thank you!
Here's what I learned: When your drone wants to come home, come home! That one extra picture isn't worth it. Use a second battery and go back for it. Also I learned that when the drone is in auto land or go home, when it reaches a point that it can no longer descend, it shuts down the motors. This is really important, because that saves the motors, the props and the shell (hot motors melt shells!). Finally, use Healthy Drones religiously - it could save you a lot of time and money and heartache!
Nothing better then to read a happy ending. I have lost 2 phantom's and was never able to find them. If I had the resources we have now I'm sure there would have been a much better ending in my case.
Thanks for sharing your story, it was a good one.
Thanks for sharing your story, it was a good one.
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