Guys, please help me out here.

I had a brand-new Spark, (this is Spark #2 so I've been flying Sparks), and a few weeks ago I took it out to a big open field.

Even after leaving it on the ground for more than 3 minutes it said "no gps" and the satellite indicator was zero.

I decided to fly it in Opti mode to have some fun with a flock of geese on the field.

As you can see, the Spark was doing fine flying over the flock, then it suddenly accelerates and crashes into the ground.   

I sent it to DJI for repair and this is what they wrote:


This is Ken from Technical Support team, and I will be assisting you on this case from now on for related inquiries about data analysis.

According to the analysis, no crash was found in the available flight records and there's obvious damage that impairs normal function of the unit. The cause of the issue is due to physical damage. Therefore the incident was not caused by any product malfunction.

We can still proceed with the repair, however, you will cover the repair charges.


For my forum friends, here's the video from the flight:  
And the log:  https://www.phantomhelp.com/logviewer/230LYW87XEUBXMTYIBHP/


According to the log, the Spark had 0 GPS the entire flight, and accelerated to 45 mph within 5 seconds and crashed.  
Here's my summary:

• No GPS acquired
• Spontaneous acceleration (I was not in Sport mode)
• Crash into the ground (ground sensor stopped working in flight?)
  

What can I do to get DJI Support to own up to the fact that their drone was defective?   They want to charge me $69 for the repair.  


Thanks for your help, friends!

Sorry this is completely random to comment on this discussion but it won't let me start my own, anyways, whenever I try to set my spark home point to my remote controller or dynamic home point, it says weak mobile GPS signal. Does anyone know why this happens or how to fix it?

Also as a answer to your question, I have always taken my drone up about 40 feet to let it gain satellites, then GPS kicks in for me

You should not fly so close to birds. They were distressed by the drone for sure. Your drone did not have satellite and was probably flying in ATTI mode. In that mode you must control everything. You should not fly without satellite unless you are prepared to make in fly in ATTI.

Hi there, we are very sorry to read about the crash accident. I managed to get your case number via your Forum account and the video and your concern of the data analysis have been escalated to the higher level team to double analyze, we will have someone to contact you soon, please wait patiently, thank you.

Hi,

From flight time 35 sec to the crash at 45 sec you constantly instructed your Spark to accelerate forward! When a copter is tilted that much, it obviously looses lift, that's what happened to you.
In ATTI mode, the Spark can get very fast, much faster than in Sport mode.
See this thread and tutorial to brush up your ATTI mode skills.
And please, as Daniella3d already said, respect animals and people when you fly. Do not bother them.

Cheers,
Wolferl

Always wait for GPS lock before takeoff. When you takeoff  your home point is where it lock the GPS

signal. Thats aching for trouble. Hate to say it but this is pilot error.

Hi,

Better take the 69 dollar loss and have your Spark repaired.

Most drone flyers have difficulty to fly in ATTI, getting their great SPARK back to home when the sh*t hits the fan.

You started in OPTI with no sats at all, taking the risk of going into ATTI wich happend at the end of the flight. Into ATTI and full fwd pitch = recipe for a crash.

cheers
JJB

Wolferl Posted at 1-29 04:04
Hi,

From flight time 35 sec to the crash at 45 sec you constantly instructed your Spark to accelerate forward! When a copter is tilted that much, it obviously looses lift, that's what happened to you.

He had strong warning at the beginning, but he didn't mind. The sequence of huge mistakes can serve to him as a helpful lesson.

Lysak2003 Posted at 1-29 06:54
He had strong warning at the beginning, but he didn't mind. The sequence of huge mistakes can serve to him as a helpful lesson.

well, he decided to fly in OPTI and yes doing that ignoring the DJI warning, wich is a genuine warning as DJI expects that their drones are flown in a GPS stabilized mode.

Guess the OP was not aware that OPTI can change into ATTI if the visual reference is getting worse for some reason....

Indeed a hard lesson. Well it is only 69 dollar.

cheers
JJB

JJB* Posted at 1-29 07:09
well, he decided to fly in OPTI and yes doing that ignoring the DJI warning, wich is a genuine warning as DJI expects that their drones are flown in a GPS stabilized mode.

Guess the OP was not aware that OPTI can change into ATTI if the visual reference is getting worse for some reason....

Let's say thank you that these geese didn't take off when the drone approached. It could be much more damege and not only for the drone. All we agree with thought that a pilot must be responsible with his actions. And I don't see responsibility on this footage.

I appreciate all the replies.   While flying above geese was probably not a great idea, I am still stuck with these two thoughts:

1.  How can the drone never have acquired any GPS signal in the approx 1 hour total flying time out in the open?   I let it sit for plenty long in two different spots, about a mile away from each other.   No magnetic interference or anything.  I've flown my previous Spark in exactly the same location and have had absolutely no problem with GPS.   My personal conclusion is that the GPS unit is defective.

2.  I would expect the ground sensor to prevent the Spark from hitting the ground even in ATTI mode.  If you look at the data, yes I was full throttle forward, but not down.  We all know that in non-Sport mode, full throttle isn't even that fast.

I appreciate most of the comments.  What I'm trying to accomplish is to determine whether the drone could possibly have been defective, and not entirely user error.

Woe Posted at 1-29 06:12
Always wait for GPS lock before takeoff. When you takeoff  your home point is where it lock the GPS

signal. Thats aching for trouble. Hate to say it but this is pilot error.

The GPS never engaged.  I waited and waited and waited.   I tried different locations.

Regarding post #12:
Item #1- This is really the issue you wanted to bring to DJI's attention.  Why can't the Spark attain a GPS lock even when trying in multiple locations.  Perhaps the GPS module is defective.  Unfortunately, the only data you presented to DJI is your wild attempt to fly your Spark at full speed 10 feet AGL in Atti mode.  As Wolferl and JJB pointed out, it is quite easy to fly the AC into the ground under these conditions.

Item #2 - Your expectations about the ground sensor exceed the AC capability.  The downward sensor is used for landing purposes only, not collision avoidance.

Conclusion:  Pay the $69 and while DJI has the drone, have them look at the GPS module.

djiuser_KYwxXolmqeoQ Posted at 1-29 08:37
I appreciate all the replies.   While flying above geese was probably not a great idea, I am still stuck with these two thoughts:

1.  How can the drone never have acquired any GPS signal in the approx 1 hour total flying time out in the open?   I let it sit for plenty long in two different spots, about a mile away from each other.   No magnetic interference or anything.  I've flown my previous Spark in exactly the same location and have had absolutely no problem with GPS.   My personal conclusion is that the GPS unit is defective.

Number 2 is a wrong thought.  ATTI mode doesn't have sport or normal mode.  ATTI mode requires the pilot to control the speed by working the stick to tilt the aircraft forward or back like an airplane or helicopter.  

Full tilt forward in ATTI mode can be very fast if the pilot holds the stick forward long enough or hard enough.  Tilted forward hard enough that all of the thrust was going to the rear and very little was available to maintain height.  My model helicopter could do this including front flips and flying inverted if I kept pushing forward on the stick while adding reverse thrust on the rotor blades.

GPS-P mode with the Spark's autopilot is what lets non-pilots fly the drone by sliding it around with the sticks.  The autopilot flies the spark (using GPS to know how it is moving) and keeps the aircraft upright while the users asks autopilot to slide forward into the distance or back.

As far as not getting GPS lock,...do you have a sticker on the top blocking the signal?  Or lead based paint?  If you have never gotten GPS lock, and don't have anything blocking the signals, it could be a defective GPS from a crash or unit fault.

My Spark would have dove into the ground, from my hard stick imputs, if the autopilot and GPS lock didn't prevent it from over tilting.  ATTI mode and OPTI mode require a delicate touch on the sticks.

Out of curiousity, did you try compass/IMU calibrating when you could get no GPS signal? Open field should've given GPS no problem.

dencio1976 Posted at 1-29 16:50
Out of curiousity, did you try compass/IMU calibrating when you could get no GPS signal? Open field should've given GPS no problem.

I did a compass calibration because it asked me to.  No IMU calibration because it didn't tell me to and the stats looked ok.

MccloudSpark Posted at 1-29 11:26
Regarding post #12:
Item #1- This is really the issue you wanted to bring to DJI's attention.  Why can't the Spark attain a GPS lock even when trying in multiple locations.  Perhaps the GPS module is defective.  Unfortunately, the only data you presented to DJI is your wild attempt to fly your Spark at full speed 10 feet AGL in Atti mode.  As Wolferl and JJB pointed out, it is quite easy to fly the AC into the ground under these conditions.

DJI asked for the full record so I sent them flight records from numerous "normal" flights, where not a single GPS satellite was acquired.  Hopefully that will prove that the GPS was defective.  

BTW, I didn't mention this, but before this incident I flew at least a dozen flights at full-throttle forward and no GPS and it maintained altitude and speed just fine.  I have videos flying above a frozen lake, etc.