Unexpected crash without reason

[mamarz]

Hallo, new here to the forum, i'm Max from Rome.

I'm an happy TH pilot, and have 70 mission goned like a charm.
On sunday, flying over Tuscany, i left my H stand still to take some pics. After did this, I tilt the camera down, and starting a right pan rotation on the floor.
Suddenly, my H start loosing height, remote said "enter five motor mode" but inevitabily my Drone was already on the floor.
Luckily it landed on a desert area, near a tree, unluckily on some hard old branchs.

My H seemed not had problem but i tried to fly again after, it seem much more unstable, one rotor makes noise, the landing gear are not more hard and didn't goes down. The gimbal camera has one of the 6 wires upper (near the contact board to the H) that is broken.

So, i think: when started the pan rotation, the bad assembly of the gimbal wires makes the green wire broke, it touch the gimbal pin and cause an overvolt, so the H looses power.
When i open the gimbal, I don't think the wire can stucked for the crash, it's in position that it couldn't touch with nothing else... And seem "cut" from cap that retain all the wires..

The camera was active and filmed the bad landing.

I've attached the LOGS, but i'm not able to read. Can someone help me reading?
I want to know if was my fault or not...

 

[mamarz]

The file drone_crashato is the video of the fallen..

 

[wings]

Noticed that at take off your battery was already at 15 volts. Fully charged is 16.6 or 16.7.

 

[mamarz]

Noticed that at take off your battery was already at 15 volts. Fully charged is 16.6 or 16.7.

Yes I know, but was a short demo flyght only for few minutes... After was still charge enough to fly again (need to test what was broken).

In the remote log see something abnormal?

 

[wings]

I will let the experts judge but it looked like your battery just got too low. Others here can give you a better report.

 

[AH-1G]

Sorry to here about the incident, but I agree 15 volts you should never, never take off on a mission even when it's short. The amount of energy to get in place and hover with winds aloft will drain faster than you can imagine. Who knows maybe the engine was shut off to save energy in order to land the drone safely somewhere?

 

[JulesTEO]

Hallo, new here to the forum, i'm Max from Rome.

I'm an happy TH pilot, and have 70 mission goned like a charm.
On sunday, flying over Tuscany, i left my H stand still to take some pics. After did this, I tilt the camera down, and starting a right pan rotation on the floor.
Suddenly, my H start loosing height, remote said "enter five motor mode" but inevitabily my Drone was already on the floor.
Luckily it landed on a desert area, near a tree, unluckily on some hard old branchs.

My H seemed not had problem but i tried to fly again after, it seem much more unstable, one rotor makes noise, the landing gear are not more hard and didn't goes down. The gimbal camera has one of the 6 wires upper (near the contact board to the H) that is broken.

So, i think: when started the pan rotation, the bad assembly of the gimbal wires makes the green wire broke, it touch the gimbal pin and cause an overvolt, so the H looses power.
When i open the gimbal, I don't think the wire can stucked for the crash, it's in position that it couldn't touch with nothing else... And seem "cut" from cap that retain all the wires..

The camera was active and filmed the bad landing.

I've attached the LOGS, but i'm not able to read. Can someone help me reading?
I want to know if was my fault or not...

Im sorry to hear about the incident. I'm looking at the files you provided, however it seems the file from the incident is incomplete (file 00073).. It doesnt show the entire flight, just 48 seconds of it which I can't really tell at the moment if are the last seconds, or just a segment of the flight.

Could you check if the previous log (00072) belongs to the same flight, and if it does share it as well?

I haven't looked too deeply into that particular file, but it does show it was in 5-motor mode, with motor 6 shut down.

Greetings!

 

[mamarz]

Im sorry to hear about the incident. I'm looking at the files you provided, however it seems the file from the incident is incomplete (file 00073).. It doesnt show the entire flight, just 48 seconds of it which I can't really tell at the moment if are the last seconds, or just a segment of the flight.

Could you check if the previous log (00072) belongs to the same flight, and if it does share it as well?

I haven't looked too deeply into that particular file, but it does show it was in 5-motor mode, with motor 6 shut down.

Greetings!

Hi JulesTEO, thanks for the answer...
I attach the precedent 2 logs with the other 3 here...

Yes, the controller said "5 motor mode" but was too late, it was landend badly...
For the battery: I didn't receive any alert, when this flyght start the charge was about 15.6-15.7v, so i was confident it could resist. And i never take risk with this, but was still much more than half charge...
However, if can tell me something better i'll grateful.

I tried to download the software from Yuneec, but my antivirus says that the package has a virus :/

Tomorrow i'll ship to the shop in Germany, but will be a long procedure...

 

[JulesTEO]

I took a look at the files, and even though I couldn't figure out what happened it seems that you got the 5-motor error mode After the crash, not before.

It looks like as soon as you were done yawing and tilting the camera down, you started Throttling up, and that's when things went wrong; for an undetermined reason the aircraft almost flipped 90º sideways as it began descending out of control; all motors were still running during descent, but still the aircraft free-falled

• Eventhough you weren't flying on a full battery you were at 14.6volts when the aircraft began twitching (its low but not too low, so I don't believe this was an issue)
• GPS accuracy did get gradually reduced in the last 3 seconds of flight; going from 0.65m to 1.55m
• 5 motor error (emergency mode) was triggered After the impact. The aircraft automatically shut down the motors.

I went ahead and opened the files on the parser app, and synched it with the recovered video you also provided; so it will give an Idea of the aircraft orientation, the inptut from the sticks and the actual footage. (sorry for the small recording I just improvised)

I'm sorry I can't tell what happened, but hopefully this interpretation and the video can help figure out what went wrong.

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Greetings!

 

[mamarz]

JulesTEO, many many thanks, your help is really appreciating.

So, you think it can be my fault or what?
As you see in the video, nothing were upper, a electric line was nearby but about many meters, and was lower than me. And nothing upon my position, no birds, no branches... I really can't figure what can happend.
I thinked even i absently turn off motor, but was a remote option.
Wind was present, but nothin so strong that can flip my H at 90°...

In the picture I measured the distance between my TH and the electric line, so this exclude even i touched a wire...

So, i really don't know what can be happen...
Hope Yuneec Europe can explain me...

 

[JulesTEO]

JulesTEO, many many thanks, your help is really appreciating.

So, you think it can be my fault or what?
As you see in the video, nothing were upper, a electric line was nearby but about many meters, and was lower than me. And nothing upon my position, no birds, no branches... I really can't figure what can happend.
I thinked even i absently turn off motor, but was a remote option.
Wind was present, but nothin so strong that can flip my H at 90°...

In the picture I measured the distance between my TH and the electric line, so this exclude even i touched a wire...

So, i really don't know what can be happen...
Hope Yuneec Europe can explain me...

No I do not think you caused it,

Please do keep us posted as to what Yuneec resolves,

Greetings!

 

[mamarz]

I'll do for sure, now i'm packing back it to the shop...
Luckily nobody was injured...this is the most scary things for me.

Thanks for all for now JulesTEO, see you soon here!

 

[mamarz]

I'll do for sure, now i'm packing back it to the shop...
Luckily nobody was injured...this is the most scary things for me.

Thanks for all for now JulesTEO, see you soon here!

Hallo again, finally Yuneec assistance reply to me and sending me back my little exapus.

I attached the response, but even if I don't understand deutsch, they're giving the fault to an incomplete gimbal calibration.
How can it be possible?! On my ST16 I didn't receive error or a bad sound so I think it must be a strange answer.

I always do a compass calibration before flying, even if I take off from near places. And always do with accuracy.

However they are sending me back with GPS reflashed, new propellers and new camera. But I'm a little bit scared now...
Some idea from you boys? View attachment yuneec.pdf

 

[PatR]

The first flights of repaired drone after an unexplained, or poorly explained crash are always nerve wracking. Take it out away from people and buildings, put 10 or 12 flights on it, and rebuild confidence in the aircraft. Treat it like it’s brand new and you’ve not flown one before, testing each feature fully.

 

[mamarz]

The first flights of repaired drone after an unexplained, or poorly explained crash are always nerve wracking. Take it out away from people and buildings, put 10 or 12 flights on it, and rebuild confidence in the aircraft. Treat it like it’s brand new and you’ve not flown one before, testing each feature fully.

Yes, this Wil be done for sure. I'm a little bit scared now, hope my copter will be full good. However I'll be in open fields for the next three weeks, and will be testing everyday.

 

[kai_bcn]

incomplete compass calibration it says...

 

[mamarz]

incomplete compass calibration it says...

Yes this i understand too but... How can be?!
Didn't hear strange sound, error on display or something else.. Something Must be showed from my ST16, don't think?[emoji21]

 

[rdonson]

Yes this i understand too but... How can be?!
Didn't hear strange sound, error on display or something else.. Something Must be showed from my ST16, don't think?[emoji21]

You should hear a beep if compass calibration completed successfully also if the calibration has been successful, all motor LED status indicators will blink continuously, the Main LED Indicator will be solid green and the aircraft will restart, you will recognize this when you hear the raising tone.

Calibrations for the Typhoon H

 

[CraigCam]

Hallo again, finally Yuneec assistance reply to me and sending me back my little exapus.

I attached the response, but even if I don't understand deutsch, they're giving the fault to an incomplete gimbal calibration.
How can it be possible?! On my ST16 I didn't receive error or a bad sound so I think it must be a strange answer.

I always do a compass calibration before flying, even if I take off from near places. And always do with accuracy.

However they are sending me back with GPS reflashed, new propellers and new camera. But I'm a little bit scared now...
Some idea from you boys? View attachment 9859

The camera strain relief mount cuts into the camera wires and is suspect in your case. If the camera fuse didn’t pop it’s possible a short could cause your in flight problems. Yuneec often flags a component as the problem when it’s really a an assembly/design issue. Clearly there were “technicians” in China who weren’t as qualified as others. There were also known faulty GPS/Compass boards (my first one had this issue) that rather then admitting and recalling, they chose to handle things on a case by case basis. You could have had a lemon but now if they really fixed should be fine.

Test without the camera first and verify all flight controls behave. Keep it within site and low enough to land or catch quickly. Once you feel good about angle, stand still and switch to smart mode. Move slowly until the H recognizes you are moving and responds accordingly. Switch back to angle to verify it’s goes back to steady hover. If it’s still funky, it will behave like smart mode and move away from you. This is an undocumented phenomenon (mystery fly aways for many) that pops up when the GPS/Compass module is confused. I’ve seen it and experienced it and it happens erratically.

 

[DoomMeister]

I know I'm getting to this post a little late in the game, but I find the cause stated by Yuneec Service to be a little hard to believe. I could understand an incomplete gimbal calibration causing erratic behavior in the function of the gimbal itself, but not causing a complete failure in the flight control.

Looking at the data for the ST-16 showed no sign of channel mixing. It wasn't until the Camera Pan was started that the craft started its plummet to the ground from a relative altitude of 35 meters. All inputs previous to this during the short clip supplied by @mamarz seemed to correlate with the video. Even the plummet seemed to match by starting about 2 seconds after the start of the Camera Pan input on the ST-16.

Here are screen shots taken from the telemetry 00072 analyzed in Helmut Elsner's Q500log2kml program, that show the comparison of data from 15:37:00 to 15:38:20. The Camera Pan starts about 15:37:29.


This shows there was no signal from the ST-16 to cause motor shutdown.


This shows there was no sharp drop in voltage indicative of a short.


This shows the downward tilting of the camera prior to the camera panning command.


This shows the fateful camera pan command and the loss of altitude and increase in airspeed as the craft fell.