Testing Follow me-mode, fly away and crash :( - happy ending! :)

[AndersGB]

I got just under 15mpg (ave) from the recorded displacement over 11sec (in the HD log).

The phantom help veiwer seems superior and very useful here as it clearly depicts acceleration. I like it a lot.

Anyway, OP has advised he was stationary so hopefully he gets some joy from DJI.

Yes, it accelerated away from me, and I didn't touch the controls.
Yes, to view the flight in the Phantom Help viewer was great, many thanks again.
Yes, I really hope I get some joy from DJI.

 

[Duncan Campney]

OK, thank you very much for your help!

I will contact DJI. I'm a little bit concerned what they will say when the software version isn't the latest, but I'll try anyhow.

For future reference, train yourself to flip the mode switch back to P mode if anything goes wrong. It takes you instantly back to the mode you're most familiar with, and cancels programmed behavior like waypoints or follow me mode. Much easier than trying to engage RTH mode.

That's what saved me when my P3P went flying off in follow me mode.

 

[trevsdad]

Yes, it accelerated away from me, and I didn't touch the controls.
Yes, to view the flight in the Phantom Help viewer was great, many thanks again.
Yes, I really hope I get some joy from DJI.

...also practice flying in 'ATTI' mode. (no GPS) If you do get a true compass error/fly away problem, this takes it off the satellite, cancels the input confusion and gives you full control and a shot at getting 'er home. It's a little harder to fly in this mode but good to have the skill, just in case.

 

[suck it up]

Fly some with the ATTI mode and learn how it is like a air hockey puck....

It really takes some getting used too.........

 

[AndersGB]

For future reference, train yourself to flip the mode switch back to P mode if anything goes wrong. It takes you instantly back to the mode you're most familiar with, and cancels programmed behavior like waypoints or follow me mode. Much easier than trying to engage RTH mode.

That's what saved me when my P3P went flying off in follow me mode.

Yes, I will definitely do that, thanks.

I wonder if more pilots than you and I have had this issue, I haven't found any posts about it in this forum.

 

[AndersGB]

...also practice flying in 'ATTI' mode. (no GPS) If you do get a true compass error/fly away problem, this takes it off the satellite, cancels the input confusion and gives you full control and a shot at getting 'er home. It's a little harder to fly in this mode but good to have the skill, just in case.

Yes, I agree. I practice a lot on my small Hubsan X4-drone, mostly indoors. Flying the Phantom in GPS mode is a breeze compared to that one.

 

[Mark The Droner]

GPS positions on tablets and smart phones tend to bounce around a lot. You ever notice? Seems to me your monitor device (smart phone / tablet) reported a bad GPS position, and so your aircraft headed to that position which was off in the woods somewhere. Because you were standing and not walking, your monitor's GPS position was not re-assessed as it normally would have been. Had you been walking, I think the chance is much better that the aircraft would have behaved as you expected.

 

[Dirty Bird]

The only thing I can figure that might cause a Phantom to suddenly take off in follow mode would be a situation where the device GPS gets an errant location, passes it to the app, & the Phantom suddenly takes off towards the incorrectly reported location. If your location on your device jumped by 2000', the Phantom would take off to follow what it believes is your current location. From your perspective your Phantom went berserk & started flying away. I have seen situations where a reported location will bounce around on a GPS, sometimes by a significant amount, particularly if you are in a marginal coverage situation such as under dense tree cover, an urban canyon, low satellite count, or poor satellite geometry. Newer GPS devices seem better at handling this with improved satellite reception & firmware that filters spurious locations, but it is still possible.

I have had my P3P fly off fast and furious while in follow-me mode as well. I simple flipped the switch back to P mode and it stopped and hovered. The screen showed GPS the entire time. Very odd, and rather alarming. Seemed like a software bug to me, and I was lucky as there were trees nearby. In my case my Phantom was high enough that it cleared the nearby trees and as soon as I put it in P mode is stopped it's mad dash.

 

[BudWalker]

The only thing I can figure that might cause a Phantom to suddenly take off in follow mode would be a situation where the device GPS gets an errant location, passes it to the app, & the Phantom suddenly takes off towards the incorrectly reported location. If your location on your device jumped by 2000', the Phantom would take off to follow what it believes is your current location. From your perspective your Phantom went berserk & started flying away. I have seen situations where a reported location will bounce around on a GPS, sometimes by a significant amount, particularly if you are in a marginal coverage situation such as under dense tree cover, an urban canyon, low satellite count, or poor satellite geometry. Newer GPS devices seem better at handling this with improved satellite reception & firmware that filters spurious locations, but it is still possible.

I analyzed a flight where this happened. That post is here.

 

[flyNfrank]

OK, thank you very much for your help!

I will contact DJI. I'm a little bit concerned what they will say when the software version isn't the latest, but I'll try anyhow.

I calibrate the compass after installing a fully charged battery to help insure this type of thing not happen. I have yet to read or speak with anyone saying they did a proper compass calibration and have their A/C fly off. Over 250 consecutive calibration on the P3 with no issues.

Each of DJI's A/C records if and when a compass calibration takes place. From experience I know the P3's have a specific location on the flight log that documents if a calibration took place per each log. From what I have been told, in the service department if there is a warranty claim the manager request a copy of all the flights uploaded to the online cloud (the one very few know about). This is also why I tell others make sure not to lie about what took place if you happen to speak with the manager because they already know the answer. Not the phone tech's are a different story. They know nothing in this area.

Anyway...good luck to you, and hope you get back in the air again soon!

 

[flyNfrank]

The only thing I can figure that might cause a Phantom to suddenly take off in follow mode would be a situation where the device GPS gets an errant location, passes it to the app, & the Phantom suddenly takes off towards the incorrectly reported location. If your location on your device jumped by 2000', the Phantom would take off to follow what it believes is your current location. From your perspective your Phantom went berserk & started flying away. I have seen situations where a reported location will bounce around on a GPS, sometimes by a significant amount, particularly if you are in a marginal coverage situation such as under dense tree cover, an urban canyon, low satellite count, or poor satellite geometry. Newer GPS devices seem better at handling this with improved satellite reception & firmware that filters spurious locations, but it is still possible.

I'm guessing something strange took place and once it over came that the A/C went into RTH. And even if the GO announced a new home point was recorded prior to launching, it may be returning to the point in which where the compass was last calibrated. Only way to know for sure on that, is to know the locations of those points.

 

[msinger]

I'm guessing something strange took place and once it over came that the A/C went into RTH. And even if the GO announced a new home point was recorded prior to launching, it may be returning to the point in which where the compass was last calibrated.

Did you assume all of this from data you saw in the flight log? If so, what tipped you off?

 

[AndersGB]

GPS positions on tablets and smart phones tend to bounce around a lot. You ever notice? Seems to me your monitor device (smart phone / tablet) reported a bad GPS position, and so your aircraft headed to that position which was off in the woods somewhere. Because you were standing and not walking, your monitor's GPS position was not re-assessed as it normally would have been. Had you been walking, I think the chance is much better that the aircraft would have behaved as you expected.

I haven't noticed that on my iPad Mini 4, but I understand what you mean. Yes, it might be the cause in this case, and as you say, I stood still and that can make it more difficult to get a correct GPS position quickly. Maybe it took an incorrect reading and started with that one and didn't get a correct reading before it crashed. But on the other hand, doesn't everybody stand still when they activate Follow Me mode? Maybe it should happen more often. And the flight to the tree took about ten seconds. Well, I don't know, and as I understand, you can't get that info from the flight logg.

Thank you for your help!

 

[AndersGB]

The only thing I can figure that might cause a Phantom to suddenly take off in follow mode would be a situation where the device GPS gets an errant location, passes it to the app, & the Phantom suddenly takes off towards the incorrectly reported location. If your location on your device jumped by 2000', the Phantom would take off to follow what it believes is your current location. From your perspective your Phantom went berserk & started flying away. I have seen situations where a reported location will bounce around on a GPS, sometimes by a significant amount, particularly if you are in a marginal coverage situation such as under dense tree cover, an urban canyon, low satellite count, or poor satellite geometry. Newer GPS devices seem better at handling this with improved satellite reception & firmware that filters spurious locations, but it is still possible.

Yes, as I said above, it might be what cause the accident. However, I had 18 satellites for the drone so I had a good GPS situation. Thank you for your help.

 

[AndersGB]

I analyzed a flight where this happened. That post is here.

Hi,
Thanks a lot, I've read all the posts there, it seems very similar to my accident. And it also seems that it has happened to some other pilots also.
I looked at the Flight Record in my iPad Mini4, and realized that I can see the position of both the aircraft and the R/C there. And the position of the R/C is correct all the time, but as you say in the above post, that doesn't mean that the drone has the correct position. Are you interested in looking into my dat-file, or shall we assume that it is the same kind of error?

 

[flyNfrank]

Did you assume all of this from data you saw in the flight log? If so, what tipped you off?

Actually that info is no good. I saw after posting it we had been looking at the wrong flight. I then downloaded and converted FLY099 and found no issues with that flight. The only thing I saw that was a red flag for me was, he uses the auto launch feature. I have seen issues with that feature in the GO app during beta testing. I always manually launch which gives more control.

Btw, he also mentioned his tablet shutting down. That happens when the tablet can not handle the resources the app is running. A Nvidia Shield K1 tablet will cure that problem instantly.

 

[AndersGB]

I calibrate the compass after installing a fully charged battery to help insure this type of thing not happen. I have yet to read or speak with anyone saying they did a proper compass calibration and have their A/C fly off. Over 250 consecutive calibration on the P3 with no issues.

Each of DJI's A/C records if and when a compass calibration takes place. From experience I know the P3's have a specific location on the flight log that documents if a calibration took place per each log. From what I have been told, in the service department if there is a warranty claim the manager request a copy of all the flights uploaded to the online cloud (the one very few know about). This is also why I tell others make sure not to lie about what took place if you happen to speak with the manager because they already know the answer. Not the phone tech's are a different story. They know nothing in this area.

Anyway...good luck to you, and hope you get back in the air again soon!

Thanks!
Well, I didn't calibrate the compass, I was close to the location where it was calibrated the last time. I checked the sensor values and they were all ok. I waited until everything was ok before I took off and then did some soft flying, everything was ok until the accident. If it went into RTH, shouldn't that be seen in the flight log?

 

[msinger]

If it went into RTH, shouldn't that be seen in the flight log?

Yes.

 

[AndersGB]

Actually that info is no good. I saw after posting it we had been looking at the wrong flight. I then downloaded and converted FLY099 and found no issues with that flight. The only thing I saw that was a red flag for me was, he uses the auto launch feature. I have seen issues with that feature in the GO app during beta testing. I always manually launch which gives more control.

Btw, he also mentioned his tablet shutting down. That happens when the tablet can not handle the resources the app is running. A Nvidia Shield K1 tablet will cure that problem instantly.

Hi, I think you are looking at the wrong flight still. I didn't use auto launch and my tablet didn't shut down.

 

[BudWalker]

Hi,
Thanks a lot, I've read all the posts there, it seems very similar to my accident. And it also seems that it has happened to some other pilots also.
I looked at the Flight Record in my iPad Mini4, and realized that I can see the position of both the aircraft and the R/C there. And the position of the R/C is correct all the time, but as you say in the above post, that doesn't mean that the drone has the correct position. Are you interested in looking into my dat-file, or shall we assume that it is the same kind of error?

Yes, I'd like to look at the .DAT. Have you already retrieved it?