Ahmed Hussain Posted at 2017-11-18 10:01
He didn't!
I think It is the programing font choice that we both don't have.

I know the pilot can pull both sticks to center down and power up and power down.  How else would it suddenly lose power without battery falling off?  And I'll bet my life that didn't happen.  The very last frame of the video looks smeared.

DarylMax Posted at 2017-11-18 11:04
I know the pilot can pull both sticks to center down and power up and power down.  How else would it suddenly lose power without battery falling off?  And I'll bet my life that didn't happen.  The very last frame of the video looks smeared.

I am very sure too that you did not accidentally do a CSC. In your case it simply would not have worked, because your Spark was not in trouble (no serious error messages). I have tested this myself soon after I had got my Spark beginning of August and I thought there was a bug because CSC did not work for me in flight. After reporting it, I got the information both here by a forum administrator and seperately from DJI support that for the Spark CSC in flight would only work in emergency situations with serious error messages coming up. If you do it in normal flight the Spark will enter into a spiral movement downwards in a controllable manner with motors on but not just fall down.

Wachtberger Posted at 2017-11-18 14:20
I am very sure too that you did not accidentally do a CSC. In your case it simply would not have worked, because your Spark was not in trouble (no serious error messages). I have tested this myself soon after I had got my Spark beginning of August and I thought there was a bug because CSC did not work for me in flight. After reporting it, I got the information both here by a forum administrator and seperately from DJI support that for the Spark CSC in flight would only work in emergency situations with serious error messages coming up. If you do it in normal flight the Spark will enter into a spiral movement downwards in a controllable manner with motors on but not just fall down.

Thanks for the info.  Waiting to see what DJI does...

   I'm still wondering why Find My Drone didn't track with the last flight.  It looks like it never moved for 2 days.  I realize it would have lost data when the remote did, but it never moved.  Any thoughts?

DarylMax Posted at 2017-11-18 11:04
I know the pilot can pull both sticks to center down and power up and power down.  How else would it suddenly lose power without battery falling off?  And I'll bet my life that didn't happen.  The very last frame of the video looks smeared.

Could be the battery fall down, why not?!

You tested that, okay, this test could bring damage also by weaken the clip time by time.

Storng wind at 400 ft could do the effect as well if the battery clips not solid.

No explanation of the fall down increase the posibility of battery fall down, this is logic since Spark's battery fallen is a normal case.


Have a look   https://forum.dji.com/thread-118534-1-1.html

Ahmed Hussain Posted at 2017-11-18 23:23
Could be the battery fall down, why not?!

You tested that, okay, this test could bring damage also by weaken the clip time by time.

the Main Board on the Spark could go bad and in this case there would be no flight data sent.  you need to recover the drone. most neighbors that I know would just keep the drone if crashed in their yard. If I drone almost hit me in the head in my yard. I would not return it without compensation.

Sorry for loss DarylMax.

I'm wondering if you got any notice that you're in the warning zone?
If I look at your location, you are near the airport and the flying zone itself is a warning zone (green).
Correct me if I'm wrong but should there be some kind of notification in the logs?

Ahmed Hussain Posted at 2017-11-18 23:23
Could be the battery fall down, why not?!

You tested that, okay, this test could bring damage also by weaken the clip time by time.

I have seen many reports of batteries falling off, that's why I check. The battery was firmly attached.

Canonian Posted at 2017-11-19 02:45
Sorry for loss DarylMax.

I'm wondering if you got any notice that you're in the warning zone?

The airport and control tower are well aware of me.  I am outside of DJI's brick wall and the tower has told me if they have an aircraft at 400 feet they have bigger problems then my drone.

bobsma Posted at 2017-11-19 02:23
the Main Board on the Spark could go bad and in this case there would be no flight data sent.  you need to recover the drone. most neighbors that I know would just keep the drone if crashed in their yard. If I drone almost hit me in the head in my yard. I would not return it without compensation.

I put some "REWARD" signs up

DarylMax Posted at 2017-11-19 07:48
I have seen many reports of batteries falling off, that's why I check. The battery was firmly attached.

I have been in video production for over 35 years.  I owned a 60k SONY BetacamSP and have used every piece of gear under the sun.  The battery was firmly attached

Just completed search #4.  Have a backyard I need to search for no way in yet. Left owner a note.



End of flight with "enhansed" audio.  Needed to do something to smile.

DarylMax Posted at 2017-11-19 11:53
Just completed search #4.  Have a backyard I need to search for no way in yet. Left owner a note.

What surprises me is the angle of the camera view. Had you set the gimbal to FPV mode and not to "Follow"? Otherwise this quite articulated angle could indeed indicate a beginning flip of your Spark that could have shut off the motors if the angle had reached something like 70° or 80° plus...

DarylMax Posted at 2017-11-18 07:43
[view_image]

Thanks to all that helped!  I'm headed out today for a door to door search.  Wish me luck!

Good luck on your search

Was thinking that if it did flip and shut down the motors, it would still be transmitting video and data, at least for a second right?  I know when I’ve palm landed and tilted to kill power (I know, me bad) th Spark still has power and is still transmitting.  Latest search came up empty, but.. plenty of people wanting to help.  People are great here in Texas.

DarylMax Posted at 2017-11-17 05:21
Last flight from iphone cache

Thanks, Elektra,

Sorry for your loss.
My GUESS is given that the Spark does not have dual compass or IMU and therefore no redundancies and uses a WiFi only transmission it is even more important not to fly near electromagnetic structures and/or congested areas as you shouldn't really with any drone.
I can clearly see the drone flying over a residential area (heavier WiFi activity) AND there is clearly a string a huge pylons as part of an electricity grid directly in front of the drone. I think the amount interference led to a signal loss and overpowered the drone to cause it to fly away.
This seems to be the only plausible explanation given DJI's feedback from the diagnostic evaluation. When you receive or buy a replacement I strongly suggest changing your flight location or buy a more powerful drone that has redundancy built in and a more effective transmission system (Mavic/Phantom).

700 miles flying over this area, and never IMU warnings.  Some event occurred, the last 2 frames of video transmitted looks like the the start of a rapid turn to the left.

It took less than nine hours on Thursday to say they don't know what happened, but no one is answering questions since.

DarylMax Posted at 2017-11-20 07:08
700 miles flying over this area, and never IMU warnings.  Some event occurred, the last 2 frames of video transmitted looks like the the start of a rapid turn to the left.

As I mentioned in post #21, from my uneducated opinion, it seems like the left turn in the last few frames is correlated with stick movements in those last moments.   In the last 4 log entries, stick movements for the RcRudder were introduced that would have resulted in a yaw to the left as shown in the last moments of the video.  As shown in your video and the logs, the aircraft was already in a roll a consistent full stick left roll.  Then in the last few moments left rudder was introduced to yaw to the left.

What was the lifespan of the propellers that were on the aircraft at the time? With such a well used aircraft, is it plausible that a well used propeller could have failed under the stress of Sports mode and a strong turn causing it to exceed the flight angle limits and shut down?

Kloo Gee Posted at 2017-11-20 18:02
As I mentioned in post #21, from my uneducated opinion, it seems like the left turn in the last few frames is correlated with stick movements in those last moments.   In the last 4 log entries, stick movements for the RcRudder were introduced that would have resulted in a yaw to the left as shown in the last moments of the video.  As shown in your video and the logs, the aircraft was already in a roll a consistent full stick left roll.  Then in the last few moments left rudder was introduced to yaw to the left.

What was the lifespan of the propellers that were on the aircraft at the time? With such a well used aircraft, is it plausible that a well used propeller could have failed under the stress of Sports mode and a strong turn causing it to exceed the flight angle limits and shut down?

Maybe a couple of days old, less than 5 flights.  But transmission loss is the huge question mark.  If a prop came off we should have at least a few seconds of video, right?  Like turning the craft sideways will kill the motors, but the video and power stay on.

DarylMax Posted at 2017-11-18 05:23
Please check your PM's,  I do need help.

Got your PM. Sorry to keep you waiting.
We reviewed your case for the details, sorry to say the reason of flyaway was inconclusive based on the flight record you provided. Since there's no sign of product malfunction, it would not be covered by warranty, we've already provided you the best solution according to after-sales policy, hope your kindly understaing.

I couldn't wait for coupons and bought a new Spark Friday at Best Buy.  I'm going to use my new Spark to help track down my missing Spark.  Thanks to all for the maps and advice.  Wish me luck!

DarylMax Posted at 2017-11-25 00:28
I couldn't wait for coupons and bought a new Spark Friday at Best Buy.  I'm going to use my new Spark to help track down my missing Spark.  Thanks to all for the maps and advice.  Wish me luck!

Oh yes I wish you good luck and there is also still hope that it will be found by someone. Luckily you have put your contact information on it.

DarylMax Posted at 2017-11-17 14:09
Battery #2, so about 100 flights.  Falling out is one I can rule out. Every single time I attach a battery I pull and tug on it a little to make sure it's clips are in.  And I don't pull on the battery too hard, just enough to be sure it stays in.

100 flights on a battery is quite a few.

Have you been doing the complete battery drain every dozen or so flights?

You have to drain it till it will not switch on. This process is not good for the battery but is a requirement for the internal electronics in the battery to calibrate the charge level.

You could for instance have a battery that is showing more than 50% charge but is actually at 5% or less charge. You can do a basic check by looking at the actual cell voltage levels.

bjr981s Posted at 2017-11-25 01:01
100 flights on a battery is quite a few.

Have you been doing the complete battery drain every dozen or so flights?

1m 3.3s        Sport        16satellites        393.7ft        0ft        31.1mph        1,009.7ft        90%        11.561V        3.854V        3.854V        3.854V        0V

That's the last bit of data the remote received. I think every dozen flights will harm the battery more than help. Thank god we are done with NiCads.

DarylMax Posted at 2017-11-25 01:09
1m 3.3s        Sport        16satellites        393.7ft        0ft        31.1mph        1,009.7ft        90%        11.561V        3.854V        3.854V        3.854V        0V

That's the last bit of data the remote received. I think every dozen flights will harm the battery more than help. Thank god we are done with NiCads.

Ok you would be on the threshold of a failure at those voltage levels on a 100 flight battery.

3.85V is the low end of capacity (KWH) for a battery of that age.

The Spark batteries are LiHVs. 4.21V per cell at full charge.

I do not understand why it is saying 90% battery level but that is obviously way out given the voltages displayed.

At 3.7V mine is showing 27% charge.

.15V does not make 63% of a charge. The difference between mine and yours.
Assuming the 90% is the Btery level nd not something else.

Your battery calibration was in error and the remaining charge was misleading. The most likely cause of your loss was the battery collapsed, particularly being in sports mode. Sports mode eats battery as it draws much higher current from the battery.

Two things happen as batteries age. The ability to store charge decreases. (KWH) and their C rating is reduced.

It is most likely that you experienced a brownout I have posted here in another thread the details.

What happens is that the Current Demand (usually when a manoeuvre is commanded)  ( like the Yaw in your record.) exceeds the C rating ability of the battery (In your case due to low charge level and age) to deliver the current required. This causes a sudden voltage drop (Brownout) this causes a reset of the flight controller. This is why the flight record just stops. So the Drone just falls from the sky. I am assuming in your case that it ended up in the water as it cant be found.

I hate the process DJI has for battery capacity calibration but if you don't do it the values that it shows are meaningless.

Personally I would be binning a LIHV that has had 100 discharges it is at EOL. Particularly if you have been discharging down to below 40% every flight.

Unfortunately DJI tell you the maximum flight time, and do not tell you that achieving that significantly shortens the battery life.

This is something that you learn the hard way flying electric RC models.

I hope this info helps. Sorry for your loss but this may save your next one.

Cheers

p.s. The calculations are based on 90% being the battery charge. If it is something else then the calcs are incorrect about comparisons, but the rest of the information is correct.

Hi, why did this happen?



http://www.phantomhelp.com/LogViewer/ZFPEV9X0URI4UYHRFO5I/

bjr981s Posted at 2017-11-25 01:56
Ok you would be on the threshold of a failure at those voltage levels on a 100 flight battery.

3.85V is the low end of capacity (KWH) for a battery of that age.

Thanks for the great analysis!  You know a great deal more then I do with the lithium polymer batteries

I checked charges on my others today:

1.  117
2.    missing with Spark
3A.   67
3B   108
4.    38
5.     1

I followed your advice and cycled them.  Thanks again

Sorry to hear that one more spark is missing. You will find it ;)
Btw. in video i see power lines, how far it was from spark? Maybe this have something to do with it?

BerkoZg Posted at 2017-11-25 22:31
Sorry to hear that one more spark is missing. You will find it ;)
Btw. in video i see power lines, how far it was from spark? Maybe this have something to do with it?

It wasn't in the past.  Most of my 700 miles were here in the neighborhood.   The battery "brown out" is the best explanation I've read so far.


Has anyone attached a Square tracker to their drone?   Does the Bluetooth cause any flight issues?

bjr981s Posted at 2017-11-25 01:56
Ok you would be on the threshold of a failure at those voltage levels on a 100 flight battery.

3.85V is the low end of capacity (KWH) for a battery of that age.

This is very good information, thank you for that! What do you mean with "complete battery drain" to be done after 12 charges in your previous post?

djiuser_50CkBhK Posted at 2017-11-25 11:15
Hi, why did this happen?

I would recommend you open a new discussion with your question and this flightrecord where it will get more attention.
Having seen it I am first of all very happy that at the end of the "adventure" your Spark has landed safely and you got it back! What I can see are the following issues:
At minute 3:23.8 you got a connection loss of 5.7 seconds which correctly triggered the Spark to RTH.
At minute 3:48.7 you tried to cancel the RTH which is difficult to understand for me.
But the real problems started at minute 3:59 when there was strong electromagnetic interference from somewhere. This was an emergency state for the Spark and it went into ATTI mode. Very luckily it restabilised after a while and continued RTH.
That is my quick analysis, but more experienced pilots will be able to tell you better. That's why you should open a new discussion with your case.

bjr981s Posted at 2017-11-25 01:56
Ok you would be on the threshold of a failure at those voltage levels on a 100 flight battery.

3.85V is the low end of capacity (KWH) for a battery of that age.

Yep, ill back your explanation, 75 cycles and then get worried, calibrate every 10 cycles.
the only other thing I could see was

There is only 1 thing I can see in the flight logs. You had your flight max height set at 390.4ft and you received the message "Max Flight Altitude Reached. Adjust in Main Controller Settings if necessary" I see that you then went ahead and changed this in settings to a higher setting allowing you to fly up to 394ft. In this change of the settings, did you accidentally change anything. Worth checking.
Only thought
Thanks[
Alex

DJI_ALEX Posted at 2017-11-26 09:38
Yep, ill back your explanation, 75 cycles and then get worried, calibrate every 10 cycles.
the only other thing I could see was

Thanks for the reply.  I didn't change any setting during the flight, other than flipping the switch to sports mode.  I am wondering if any DJI enginers can comment on my battery voltage.  The flight log clearly shows 90% battery at I minute into the flight, but only 3.85 volts.

FOUND

DarylMax Posted at 2017-11-28 06:49
Thanks for the reply.  I didn't change any setting during the flight, other than flipping the switch to sports mode.  I am wondering if any DJI enginers can comment on my battery voltage.  The flight log clearly shows 90% battery at I minute into the flight, but only 3.85 volts.

Missing battery and one prop.  The video ends at the same point that the cached version does

Trying to upload data

Wow, this is fantastic news! I have always been hoping for it to happen. Did you find it yourself or did someone else contact you?

Great news. How do the battery clips look on the spark?

DarylMax Posted at 2017-11-16 18:35
Never a problem with where I was standing.  What was strange was losing signal when I did.  I was near 400 feet in altitude and 1000 feet away, always a strong signal.  RTH has always worked for me.  Some event happened today.

I think it must be the battery .  A sudden loss of signal and flight log points to this direction.  Did you fully charge the batteries ?
Did you see any irregularities in the battery voltage.  How long since  you bought  the SPARK ?

We need a FAA personnel sort of thing to investigate in such scenarios .  DJI must begin this admin angle.