It just flew away! - <correction> it didn't fly away at all.

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I am an experienced pilot with hundreds of flight hours and several drones including the P4 and Mavic Pro. I am not asking for advice but merely telling the story for your own information. I was in beginner mode for a quick photo shoot over a marina. After a few minutes of good flight, the Mavic Pro lost connection and just flew away. Everything was calibrated and I had recorded the RTH location. All batteries and controller were fully charged. The Mavic suddenly rose to over 900 feet in the air (despite my RTH height being set to 100 meters) and just flew away and was non-responsive to manual controls. I hit the RTH button but no response. I tried the combination of manual flight and RTH five times but soon it was nearly 3,000 feet away an over the water. The Find My Drone feature shows it in the water over a mile away. I have opened a case with DJI and they have the flight log records and all associated files and are analyzing. I guess my only question is should I expect a new drone from DJI? I have spent $5,800 with them on my drones, accessories and drones for some of my close friends. I am certainly a good customer.
 
After a few minutes of good flight, the Mavic Pro lost connection and just flew away.
You may get a quicker answer to the "fly away" here so you can know what to expect from DJI. I wouldn't hold my breath on a replacement, but upload you flight log here and let a few others take a look. Re-post a link back to your log.

DJI Flight Log Viewer
 
Hard to say.

Even with regular RC aircraft fly-aways happen. I had one helicopter take off and got carried by the wind like a kite once clearing tree line. I suspect it broke connection in the 2.4Ghz band as it was dropping by itself at times, and then picking up the signal and climbing again when I hit the Up stick. Dunno, but I found it several houses away from all the dogs barking when it crashed onto a pool deck in someone's yard. At some RC jet fly event, guy took off at 100+MPH and the thing kept going straight away off into who knows where. Zero control on RC.

This RC stuff ain't fail-safe. Stuff happens.
 
I just uploaded the flight log (621fb61). It seems to have behaved exactly as I thought. You can see the RTH activated many times and the drone just kept getting farther and farther away. Bummer not to expect some type of refund from DJI but I guess I understand. With electronics, stuff happens.

Here is the link to the log:
DJI Flight Log Viewer - PhantomHelp.com
 
I've wondered if or when it breaks connection out of the RC itself (Not GO.), if it resets the home position to where the RC link is re-captured on the re-booting of the RC where the voice says "Setting home point?" If so, the RTH may be someplace new and if it keeps breaking the link, the RTH may be where ever. Dunno.
 
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That is a good thought and I have wondered the same. The "new" home point setting was an area that I was near during the flight but I was not that much north. I would have been within a couple hundred feet of the "new" home point so it is definitely possible. If you are correct, that is unfortunate because unless you hear the Setting Home Point audio announcement, you may never know it has changed as your mind is on other things during a flight.
 
I can answer the first question I think. According to the log, the home point remained the same for the entire flight.
 
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Yeah, I see that so it should have come home. I also notice, after continued reading of the log, that the drone is "backing up to avoid obstacles". It was over 400 feet in the air so there are no obstacles that high. The condos are 4 stories and about 80 feet high max. I think the device just went nuts.
 
This is most likely just erroneous data, but why would the VPS be reporting altitude readings, when the barometer altitude is over 400ft? just a curiosity. Probably means nothing, but it did this 3 or 4 times during the flight and that does not include the normal takeoff values.
 
I just uploaded the flight log (621fb61). It seems to have behaved exactly as I thought. You can see the RTH activated many times and the drone just kept getting farther and farther away. Bummer not to expect some type of refund from DJI but I guess I understand. With electronics, stuff happens.
Phantoms don't usually just fly away and I expect the same is true for the Mavic.
Looking at your flight log, I see some parts that don't quite match your story.
But that's OK, confusion is common and that's why we have recorded data..

I think this flight will be one of those painful lessons that is very effective because it will cost you.
The cause appears quite obvious.
What can you say about the wind conditions that day?

After a few minutes of good flight, the Mavic Pro lost connection and just flew away.
The flight record does not agree with this.
The Mavic maintained connection and was responding to your controls the whole time.
The Mavic suddenly rose to over 900 feet in the air (despite my RTH height being set to 100 meters) and just flew away and was non-responsive to manual controls.
There have been cases of Phantoms and Mavics climbing when they were pointing into the sun and obstacle avoidance was to blame because it kept climbing to avoid hitting what it thought was an obstacle.
But I don't think that it the case in this incident.
Looking at the flight record, it shows the left stick being pushed hard forward from 9:39.2 - 10:42.5 and again from 11:03.9 - 11:05.2.
That is the cause of it climbing to 935 feet.
and just flew away and was non-responsive to manual controls. I hit the RTH button but no response. I tried the combination of manual flight and RTH five times but soon it was nearly 3,000 feet away an over the water.
From 11:12.6 you brought the Mavic back down and closer by using full left and right sticks.
When you eased up on the right stick your speed quickly slowed.
When you tried Sport mode, with full right stick, the speed went up to 20 mph and you were getting closer.
You brought it down to 432 feet and only 387 feet away at 12:45.5 when you engaged RTH mode.
You left the Mavic at 432 feet from then on.
In RTH with no stick input, the Mavic is going backwards at 2-9 mph
From 13:49.8 you mysteriously pulled the right stick hard down sending the Mavic backwards at greater speed and quickly lost another 300 feet distance.
And from then on you didn't touch the right stick letting the Mavic be blown away.

Some points to remember to prevent this sort of thing.
The wind is always stronger up high.
If your drone is struggling against a headwind, bring it down lower where the wind is less.
RTH is a slow driver. If RTH isn't making headway against a wind, take over and do the driving yourself.
You can fly 50% faster (in still air) than RTH.

Your Mavic didn't just fly away, you allowed it to be blown away.
It should have been a simple matter to bring the Mavic back when it was only 387 feet away at 12:45.5.
Simply descending would have made it easy.
If you look back earlier in the flight from 70% - 60% you flew almost the same direction at 104 ft and could travel at 17 mph with full right stick.
 
Hi Meta4. Thank you for the reply. I appreciate you taking the time to review the flight log. Here are my thoughts on what your wrote:
1) There were spurts of wind but it was not a super windy day. I agree that wind is higher at higher altitudes so wind surely did play some part
2) The climb to 935 was planned as I was directly over the marina and I was recording a steady, ascending video straight upward from the center of the marina. I got that shot and everything was working fine
3) From there, the RC controller stopped displaying anything on the screen. I was not in visual site of the drone as I was blocked by the building. I was flying with the RC display on my Samsung Galaxy S7.
4) Because I could not see anything on the screen (and it showed RC disonncected), I hit RTH. During the time that I was trying to gain control of the drone, I am sure that during my various manual flight modes I would have been erratic. I had no visual site on the drone and the feet and height were no longer displaying on the screen. Those the key indicators when flying without visual site. You need to know your location, distance away and height to pilot the drone back to your location. Those were no longer moving, changing or going in any direction on the screen.
5) Once I realized I had no screen to display, distance or height for me to navigate, I engaged RTH. As you can see, it did not respond and continously got farther away. It seemed to think a new RTH point had been recorded in the water a mile away. You did not address in your response.

I disagree with the statement that I allowed it to be blown away. When the device will not respond to controls and screen display is gone/disconnected then RTH is supposed and was designed to bring the drone home and at least back into visual range. When that does not happen, and I cannot see the drone, how can you blame the pilot? Kind of like blaming the buyer of the Remington guns for their faulty product that fires unexpectedly.
 
It's not surprising that you lost signal 900 feet straight up.
Straight up is the worst angle to maintain signal.
I engaged RTH. As you can see, it did not respond and continously got farther away. It seemed to think a new RTH point had been recorded in the water a mile away. You did not address in your response.
I'll address that now.
Your initial home point was 27.459062 -80.308703
At the end of the flight, the home point stored by the Mavic was: 27.459062 -80.308703
I don't know why you would think a new home point had been set (or how that could have happened).
The flight log is very clear. Your Mavic was trying to get back home but being blown backwards.

I disagree with the statement that I allowed it to be blown away. When the device will not respond to controls and screen display is gone/disconnected then RTH is supposed and was designed to bring the drone home and at least back into visual range. When that does not happen, and I cannot see the drone, how can you blame the pilot? Kind of like blaming the buyer of the Remington guns for their faulty product that fires unexpectedly.
And I stick with my assessment of 100% pilot error.
I'd suggest you read it again because a lot of work went into it.
On the bright side others can learn from your mistakes even if you don't.
When the flyer puts their drone in a situation from which it can't get back and has a poor understanding of what it can and can't do, it's no-one else's fault.
The Mavic did not exhibit any sign of being a faulty product and operated exactly as it was designed.
As fighter pilots say: Lose sight, lose the fight.
If you want to take your drone home, you must maintain situational awareness.
If you don't know where it is, how do you ensure you avoid crashing or flying behind and obstacle?
Your lack of experience and understanding allowed it to be blown away when it should have been easily brought back.
Your thread title is misleading too as the Mavic did not fly away. It was running its battery down trying to get back to you.
If you'd just brought it down from 432 feet this thread wouldn't have been written.
 
Also, in your original post you sure made it sound like it rose to 900 feet on it's own, now you say you did it on purpose. So I'm not really sure what to think at this point.
 
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I agree with @Meta4 assessment. And to me this flight was in jeopardy right from the start. Assuming the image here is correct where the home point is marked, that was a mistake. Taking off there was not a great idea with the building right in front of you which could have impacted your signal. It would have been prudent, although what is done is done, to walk over to the fully open parking lot where you would have had clear visual for the flight.
Launch Point.JPG
 
All good points. I thought the product was more robust that it could handle a 80 foot building and virtually no wind. If you really think that a slight breeze (5 mph-ish at ground level and maybe higher at 900 feel) disconnected the RC, froze the screen and drove the device backwards 2,000+ feet then I guess so be it and lesson learned on my part. Additionally, if visually watching the drone at all times is required (I know it is recommended) then that really hinders the usefulness of the product as well. I will keep everyone posted on the outcome with DJI on the issue. I truly appreciate the responses and the time put forth.

On another note, the biggest knock about this forum is the "snarkiness" of some of the posts. There is a tone of rudeness and defensiveness that starts to build-up and I think some of those folks should consider toning it down if they want more participation. I was concerned to even post because I have seen this in the past with other pilots that dared to question the great DJI in this forum. I think if you read my posts and the posts of Fly Dawg and GMack you see a tone of professionalism and politeness despite the direction of the thread. When Meta and AirMan weigh in it becomes a sour tone. Words and phrases like below are really not needed:

1) "don't quite match your story"
2) "you mysteriously pulled the right stick hard down sending the Mavic backwards at greater speed and quickly lost another 300 feet distance. And from then on you didn't touch the right stick letting the Mavic be blown away."
3) "Your lack of experience and understanding allowed it to be blown away when it should have been easily brought back"
4) "Your thread title is misleading"
5) "Also, in your original post you sure made it sound like it rose to 900 feet on it's own, now you say you did it on purpose. So I'm not really sure what to think at this point"

This is a forum and not a court of legal authority. I was not expecting every word to get dissected and thrown back at me. I wrote my initial post in a minute without thoroughly examining the flight log so some details were missed or incorrectly remembered. Remember guys, one of your forum members just had a $1,000 drone vanish. Try to cut down on the sour tone and snarkiness and just help where you can with facts.
 
To me it seemed like a polite way to explain that you made some pilots errors. None of it seemed harsh. :shrugs: A hard lesson learned for sure. Sorry for the loss mate!
 
You first stated that it went to 900' while in Beginner mode, without input. Now you say you climbed to that height intentionally, but that can not be done in Beginner mode. You do not mention changing modes or the building right in front of you, that was likely blocking the wind.

The max speed varies with the mode, but if the wind is faster than max speed, you are going to be flying backwards, out to sea. Full throttle will not get you back.

Air speed above the building could easily be much faster than behind it, something you might have been able to see, if there had been flags or birds or other indicators that might have hinted of high upper level winds.

The log seems to show that you were in control, but if the wind was too strong, you may have thought it was not responding. From 900 feet, it is hard to tell much visually with such a small craft. Easy to get disoriented, even with the display.

Don't be too defensive, people will read your post and if your explanation seems odd, they will wonder about your account. Be precise and read your post before posting to be sure your word express your thoughts.
 
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