Hello,

last month while I was flying and capturing some event outdoor with spark, when the battery is down to about 2 minutes 20seconds flight time,

the low battery warning pop up and I pressed "return to home location",

spark then flu to 30m height (as in the settings) and head straight towards home location,

which is on the other side of a building, but the sensor didn't work and it flu right into the building and crashed.

I've sent crash report to DJI support with DJI GO 4 APP a while ago, but didn't get any response.

should I post the fly log, video here?  not sure if it's software issue or hardware issue

thanks!!

sorry for the incident.
i was checking the manual and on page 15 it says that the obstacle avoidance system is active during RTH if the procedure is triggered when Spark is 100m or less from the home point.
would be good to post your logs here for a better understanding.

thanks,

dj_dread Posted at 2018-3-8 01:51
sorry for the incident.
i was checking the manual and on page 15 it says that the obstacle avoidance system is active during RTH if the procedure is triggered when Spark is 100m or less from the home point.
would be good to post your logs here for a better understanding.

Hello dread

thanks for your reply!!

hope this is the right file
here

here's a screenshot of the flight record


thanks!

If you were outside 100 metres then obstacle sensors will not be available on RTH so I think this could well have been your problem, you should set your RTH height above all obstacles in the vicinity you are flying in.

hallmark007 Posted at 2018-3-8 05:00
If you were outside 100 metres then obstacle sensors will not be available on RTH so I think this could well have been your problem, you should set your RTH height above all obstacles in the vicinity you are flying in.

I see, thanks for the information!!

I checked it's 125m when RTH activated, and the height was slightly above the building,

got unlucky it hit the solar panel thingy on top of the building...

guess the best way to avoid this is land manually!

JAGON Posted at 2018-3-8 05:05
I see, thanks for the information!!

I checked it's 125m when RTH activated, and the height was slightly above the building,

Jagon, you start a case with our support, right? Please provide us the case number for further check. Thanks for your support.

DJI Elektra Posted at 2018-3-8 23:47
Jagon, you start a case with our support, right? Please provide us the case number for further check. Thanks for your support.

Hello Elektra,
thanks for your reply, this is also my concern,

I didn't get any confirmation or case number both time I tried to send it

only a pop-up window says something like we have received your report, there should be an automatic email right?

I sent it through DJI GO 4.0 android APP, under DJI Support -> Problem Reports

(also took so many tries on the Flight Record Upload, turns out it only worked if I use 4G, not Wifi)

thanks again for your time!!
have a great weekend

JAGON Posted at 2018-3-9 22:40
Hello Elektra,
thanks for your reply, this is also my concern,

Jagon, please contact our support and start a case first: http://www.dji.com/support Please provide us the case number then. Thanks for your support.

DJI Elektra Posted at 2018-3-12 23:51
Jagon, please contact our support and start a case first: http://www.dji.com/support Please provide us the case number then. Thanks for your support.

Hello Elektra,

thanks for the reply
I think the problem is solved, RTH while more than 100 meters the sensors won't activate.

will be more careful next time!!

I crashed into a water tower with basically the same circumstance.  I wasn't running low on battery but, my drone did enter RTH mode and flew into the water tower.  DJI said the drone operated as designed and that it hit the water tower because the obstacle avoidance sensor couldn't distinguish the obstacle because it encompassed the entire sensor area.  They also of course mentioned that I should set my RTH height higher than the highest thing in my path.  

JAGON Posted at 2018-3-13 00:11
Hello Elektra,

thanks for the reply

I see. Thanks for your update. Have a nice flight.

The Bash's Posted at 2018-3-13 00:59
I crashed into a water tower with basically the same circumstance.  I wasn't running low on battery but, my drone did enter RTH mode and flew into the water tower.  DJI said the drone operated as designed and that it hit the water tower because the obstacle avoidance sensor couldn't distinguish the obstacle because it encompassed the entire sensor area.  They also of course mentioned that I should set my RTH height higher than the highest thing in my path.

What is the model of your drone? If your drone is under warranty, you can start a case and provide your flight records to our support: http://www.dji.com/support Thanks for your support.

DJI Elektra Posted at 2018-3-13 02:09
What is the model of your drone? If your drone is under warranty, you can start a case and provide your flight records to our support: http://www.dji.com/support Thanks for your support.

It is a spark, I already sent it in and they said it was operator error and billed me for the repair.  

The Bash's Posted at 2018-3-13 12:42
It is a spark, I already sent it in and they said it was operator error and billed me for the repair.

I see. Hope you can get back your drone soon. Please contact us if you have doubt in your case.

Too many pilots rely on the RTH function to bring their drone back to the home point. I don't believe this function was meant to be used in this manor. As for me, I only used the RTH function in emergencies! I fly my drones back the the home point and land them myself. I rely on my skills as a pilot rather than the drone flying itself into objects.

MJLSTUDIOS Posted at 2018-3-15 02:59
Too many pilots rely on the RTH function to bring their drone back to the home point. I don't believe this function was meant to be used in this manor. As for me, I only used the RTH function in emergencies! I fly my drones back the the home point and land them myself. I rely on my skills as a pilot rather than the drone flying itself into objects.

good point!!! I also never used the RTH before,

when it happens, the drone was above crowds of people at about 4 meters height,

the low battery warning pop up and I kinda panicked and pressed "OK" for RTH

then I lost control of the drone and can only watch it happen...

lessons learned!!

JAGON Posted at 2018-3-15 03:32
good point!!! I also never used the RTH before,

when it happens, the drone was above crowds of people at about 4 meters height,

Just one more thought with some advice, I set my low battery warning at 30% and critical battery warning at 10%. At 30% you should have enough time to make your way back to the home point, and, at 10% it should give time to find a safe landing spot.

MJLSTUDIOS Posted at 2018-3-15 02:59
Too many pilots rely on the RTH function to bring their drone back to the home point. I don't believe this function was meant to be used in this manor. As for me, I only used the RTH function in emergencies! I fly my drones back the the home point and land them myself. I rely on my skills as a pilot rather than the drone flying itself into objects.

While I definitely agree that a pilot should be proficient in manual flying, if the RTH settings are correct for the environment you are flying in, it works great!  

I use it occasionally simply because I love the tech the Spark has and it always amazes me lol.  When I use it, I'm always ready to cancel and take over if necessary, but to date have never had to do so.  I always ensure that my RTH altitude is set higher than any obstacles in my area.  

Why not use it?  It's a technology that works great and IMO is not just for emergencies.  Plus, if you don't become familiar and understand exactly how it acts in various situations, you will never trust it.  I cringe when I read about people that have never used it.

Hddeuce Posted at 2018-3-15 06:01
While I definitely agree that a pilot should be proficient in manual flying, if the RTH settings are correct for the environment you are flying in, it works great!  

I use it occasionally simply because I love the tech the Spark has and it always amazes me lol.  When I use it, I'm always ready to cancel and take over if necessary, but to date have never had to do so.  I always ensure that my RTH altitude is set higher than any obstacles in my area.  

Agreed. If you know where your drone is (and you should, at all times!), and if you have your RTH altitude set in accordance to its environment, using RTH doesn't have to be limited to emergencies at all. Sometimes it's just more comfortable to watch it come back, without having to hold the stick. There is "Tap&Fly" as an alternative without the pesky beeping, but it is much slower.

KurtVD Posted at 2018-3-15 19:29
Agreed. If you know where your drone is (and you should, at all times!), and if you have your RTH altitude set in accordance to its environment, using RTH doesn't have to be limited to emergencies at all. Sometimes it's just more comfortable to watch it come back, without having to hold the stick. There is "Tap&Fly" as an alternative without the pesky beeping, but it is much slower.

I would add having your finger on the pause button ready to press when things look like they are not going according to plan. I like testing out the tech of it too, but usually manually fly back. I especially like how precision landing works.

Tom_A Posted at 2018-3-15 19:34
I would add having your finger on the pause button ready to press when things look like they are not going according to plan. I like testing out the tech of it too, but usually manually fly back. I especially like how precision landing works.

To be honest, I never let it land on its own, because I usually control it from a place where there are trees nearby - way to risky. I have the RTH altitude set to a 100m - MUCH higher than anything around - so that I don't have to worry about its flight path, but once it is nearby, I take over.

Tom_A Posted at 2018-3-15 19:34
I would add having your finger on the pause button ready to press when things look like they are not going according to plan. I like testing out the tech of it too, but usually manually fly back. I especially like how precision landing works.

Yes!  I don't know how many times I've read where people end up crashing in situations where they could have simply used the pause button!  The pause button is WAY underrated IMO.

I had the same thing. My Spark crashed into the large industrial chimney while RTH-ing. That was a surprise for me because I thought that obstacle avoidance always works in RTH mode.
Does anyone know why it works this way? What is the technical reason for disabling sensors further than 100 meters? I thought it should be completely autonomous. Is there any way to change this setting?

MJLSTUDIOS Posted at 2018-3-15 02:59
Too many pilots rely on the RTH function to bring their drone back to the home point. I don't believe this function was meant to be used in this manor. As for me, I only used the RTH function in emergencies! I fly my drones back the the home point and land them myself. I rely on my skills as a pilot rather than the drone flying itself into objects.

Also agree with MJLSTUDIOS, about the RTH function. On several occasions, while testing this function, I had to cancel it to avoid a crash. Now, I never use RTH to bring back the spark at the end of a flight.
S.

Eugene K Posted at 2018-9-6 04:49
I had the same thing. My Spark crashed into the large industrial chimney while RTH-ing. That was a surprise for me because I thought that obstacle avoidance always works in RTH mode.
Does anyone know why it works this way? What is the technical reason for disabling sensors further than 100 meters? I thought it should be completely autonomous. Is there any way to change this setting?

Speed.  Poking along like a blind man feeling his way with obstacle sensors (10 foot detecting range?) wouldn't work for longer RTH distances.  It would take forever and likely land half way due to battery exhaustion.  It needs to hussle back at speeds greater than the Spark can safely avoid obstacles when a long ways out.

Autopilots reduce the workload of the pilot.  It doesn't eliminate the need for a pilot.  A Spark autopiloting back to home needs to be monitored by a responsible pilot with his thumbs ready on the sticks.

Gunship9 Posted at 2018-9-6 09:37
Speed.  Poking along like a blind man feeling his way with obstacle sensors (10 foot detecting range?) wouldn't work for longer RTH distances.  It would take forever and likely land half way due to battery exhaustion.  It needs to hussle back at speeds greater than the Spark can safely avoid obstacles when a long ways out.

Autopilots reduce the workload of the pilot.  It doesn't eliminate the need for a pilot.  A Spark autopiloting back to home needs to be monitored by a responsible pilot with his thumbs ready on the sticks.

>>>I had the same thing. My Spark crashed into the large industrial chimney while RTH-ing. That was a surprise for me because I thought that obstacle avoidance always works in RTH mode.
Does anyone know why it works this way?

Read the manual and it won't be a surprise. You need to know what is around the area you are flying and you need to set the RTH height higher than any of the potential obstacles.

sorry to hear from your crash mate , Regardless we will all learn from your Misadventure ...
im still learning from mine

KurtVD Posted at 2018-3-15 19:29
Agreed. If you know where your drone is (and you should, at all times!), and if you have your RTH altitude set in accordance to its environment, using RTH doesn't have to be limited to emergencies at all. Sometimes it's just more comfortable to watch it come back, without having to hold the stick. There is "Tap&Fly" as an alternative without the pesky beeping, but it is much slower.

I so do agree with KurtVD,, RTH is great, but you need to be able to see your drone and have the height set to avoid obstacles on the way back.. I always use RTH,,