Disaster averted - Phantom dropped from the sky....

[Steve J Miller]

Well, disaster was averted today thank God!

I went out to Letchworth State Park in NY to get some video - was a beautiful day. Did all my preflight checks, calibrated compass and flew for a few minutes over land to make sure everything was working well. I started out using Litchi on my TabS2. After a few minutes the app crashed so I just restarted it and it connected again and flew fine - This has happened once in a while so I didnt give it to much concern. After the 2nd time I decided to bring it in. I landed, turned everything off and started over with DJI Go. I brought it over the middle of the falls and flew around taking some video. At this point Im around 350' above the water below the falls - I started bringing it toward me then everything went black. All of a sudden I was loosing control - I was able to get if flying toward me in manual control then she just dropped. I thought for sure she was gone and ran over to the stone wall. I looked over and saw her resting on her side on around a 1' ledge of grass.

I cleaned her off and did a test flight over grass and everything seems fine

I have no idea what happened but cant believe I have her home. Any incite or help would be greatly appreciated -

FYI - Up till today I have never had any issues. Last week I did a cold IMU calibration and have flown since without issue. All lights were good, signal was good, compass was good - absolutely no signs of issues. I had the TabS2 on wifi and mobile data but there wasnt much cell coverage. I was connected to 16 satellites but in Healthydrones it showed my GPS signal as fair.

Its one thing to have it fall and be able to send it back for repair but I was about an inch away from never seeing it again

If/when a phantom drops from sky with no apparent reason is there anyway to diagnose?

 

[Mark The Droner]

When you started over, you used a fresh fully-charged battery, right?

Would you show us your healthydrones logs?

 

[m0j0]

Healthy Drones and share the link. I'm sure some guy smarter than me will be able to figure out what happened.

 

[Steve J Miller]

I think this was the flight from the crash

HealthyDrones.com - Innovative flight data analysis that matters

 

[Steve J Miller]

Here's a pic of the ledge it landed on - Cant believe how lucky I was -

 

[Wingfan04]

Was the battery fully charged just before flight? And the healthy drones you posted says you were using litchi. Thought you said you switched to dji go app on crash flight?

 

[Steve J Miller]

Apparently there were no logs from the flight that crashed - the one above was two before the crash flight and this is the link to the last one before the crash flight -

HealthyDrones.com - Innovative flight data analysis that matters

For some reason I dont have data or video of the flight that crashed - (Maybe since the power to the drown went off in mid air?)

I started the day with 2 fully charged batteries - I was still on the 1st battery and the flight that crashed started at 75% and probably crashed at around 58-60%

-

 

[RVD98072]

in general, you shouldn't take off unless the battery is full. i.e., don't land and then take off again on the same battery.

 

[Steve J Miller]

in general, you shouldn't take off unless the battery is full. i.e., don't land and then take off again on the same battery.

That sounds strange - I never heard that before...

 

[RVD98072]

yeah i know it sounds weird (it's not like we do that with other battery operated things) but i think because these are lithium batteries, it's not always easy to tell how much capacity is left simply by the voltage reading, etc.

so the recommendation that you'll hear from others (i'm sure many more will chime in) is that you should top up your batteries before taking off and you should only take off on a full battery. once you land, remove the battery and use a fresh new battery (even if you land with a lot of battery capacity remaining), etc.

 

[Steve J Miller]

yeah i know it sounds weird (it's not like we do that with other battery operated things) but i think because these are lithium batteries, it's not always easy to tell how much capacity is left simply by the voltage reading, etc.

so the recommendation that you'll hear from others (i'm sure many more will chime in) is that you should top up your batteries before taking off and you should only take off on a full battery. once you land, remove the battery and use a fresh new battery (even if you land with a lot of battery capacity remaining), etc.

Good to know!

 

[Wingfan04]

You say you started the day with two fully charged bats. When did you fully charge them? Same day? Night before?

 

[Steve J Miller]

I topped them off this morning around 2 hours before flight

 

[Phantom751874]

I topped them off this morning around 2 hours before flight

Ya, don't take chances. Always start with a 100% battery even if it means wasting the use of a mostly charged battery. That's partly why I have 4+ batteries. It's a issue for sure with the P3's.

 

[Phantom751874]

Not sure where to ask this, but I took off using the "Auto" launch in DJIGO. I flew around a while and pressed the Go Home Button on the controller. The drone took off and apparently headed for a home position that I had a few days ago. For some reason, I could not cancel the Go Home command and the drone landed about 50 yards from any place. I don't think any damage was done. Is there a difference between the button Go home and the device Go Home?
At ant rate, I will do a GPS calibrate before taking off again.

Read the manual again and fully understand the RTH function. There are many caveats to its use. I wouldn't use it casually either but that's just me. I also wouldn't use auto launch or auto land either. Again just my preference and many others too. I prefer to have full control throughout flight including launching and landing. If RTH kicks in on its own no big deal but learn to take over once you regain signal.

 

[dirtybum]

Any chance the "falls" got the bird a little misty causing a small electronic short

 

[Mark The Droner]

That sounds strange - I never heard that before...

On my P2V, there's a sticker on the bottom of the craft with a pre-flight check list. One of the items is to be sure you launch with a fully charged battery. Not sure if the P3 includes this but it's definitely in your manual.

 

[happydays]

in general, you shouldn't take off unless the battery is full. i.e., don't land and then take off again on the same battery.

I do this all the time with no issue.

 

[happydays]

Couple of things.

1. What firmware are you on?
2. Litchi automatically uploads to HealthyDrones, DJI GO app doesn't; you will have to manually upload that file.
3. Healthydrones information is really limited for crash assessment. If you can extract the .DAT files from the phantom and post a dropbox link to the flight on here, some kind soul could run it through datcon for you and interpret the results using dashware.

 

[Steve J Miller]

Any chance the "falls" got the bird a little misty causing a small electronic short

I thought about that - The midst was coming from well below the drone and I would think the propeller wash would push the midst away from the drone - I did inspect it careful after and did not see any sign of moisture anywhere including the camera lens -