Phantom Lost & Found. What went wrong?

Rene75 · Oct 1, 2013

Could you please have a look at my video and analyse what I, or the Phantom did wrong?
I wonder why it didn't fly back after I switched to Failsafe and eventually turned off my RC.

It started in Denekamp, The Netherlands
Fully charged battery
Did a calibration before flight (NAZA M v. 2.18)
GoPro Hero 3 black (Wifi switched off)
Zenmuse H3-2D (upgrade kit)
Started in GPS mode
Waited for the green light

Here's the link to the video:
http://youtu.be/gXr6xwrHckU

With Google distance measure it flew away about 430 meters and started hovering (thank God!).

I read so much about flyaways and crashed with the Phantom that it starts to feel scary having it in the air. Knowing it can all of a sudden do it's own thing. This movie is not about making DJI look bad. I see so many negative responses on YouTube from drone crashed, fly aways etc. Responding only negative is not so constructive. It's about flying drones safer, so we all can keep enjoying flying them.

So please have a look and I love to hear your response/analyses.

Kind regards,

Rene

Driffill · Oct 1, 2013

Re: Phantom Lost & Found. What went wrong?

Green flashes mean its in GPS mode, its doesn't mean the home location has been recorded. Did you wait for the 20~ "fast flashing" green lights??? That's the signals for the home recorded.

It may have recorded the location correctly but not had the juice in the battery to fly back against the wind to get there, using up what was left causing it to land. Also the RTH will only climb 20m if it is 20m within the take off height. If you lose radio with the phantom at 21m above where you took off, it should just return with no altitude change until it above the home point, then land.

It's a hard call about it being a flyaway. You mentioned a couple of pilot errors that contributed, but that's not to say the naza worked flawlessly either

Wait!comebak · Oct 1, 2013

Looks like more pilot errors as you've noted mate, it was coming back when it had to land due to low battery which looking at your time line is about right with gimble & wind I think,maybe?
Glad you got it back, I've still got one missing, pilot error as I had it way up taking photos while doing other stuff, had machinery running next to me( couldn't hear phantom motors running/changing) looked up, no see him, picked up controller to lower & fly towards me, may have flown it away. Expected to walk over to below where I last seen it as it would have low Batt. crash/landed, 4 hours of walking through long grass on a rocky hill looking for a beautiful blinking red light in the dark resulting in only sore knees & ankles.
I'm thinking of putting it's image on a milk carton to see how many I can get :idea:
Anyway this is about you not me

Glad you found it!
P.s on my new one I installed one of those led headlights as others have done, unless you're miles away they are excellent for orientation, a must have unless you go Fpv

mikrob · Oct 1, 2013

The music is perfect in the video. It is tense when the Phantom is coming towards the trees. And changes to relief when it just misses the branches.

PJA · Oct 1, 2013

Incredible Landing!

Great Video and Captioning...

Glad you got it back!

I couldn't even give you a clue as to what happened. Two weeks ago, mine flew erratically also and didn't return with the Fail Safe method... Just hovered till it lost power, then plunged 150 Ft.... What a mess... Had to rebuild my Phantom... First test flight will be today...

Anyway, It's getting more scarier as I read these "flyaway" posts, where as it's starting to take away the fun of flying the Phantom... You never know what's going to happen... Pilot error or not...

I hope you find out what went wrong and let us all know...

Good Luck...

martcerv · Oct 1, 2013

Very lucky and by the look of it you lost radio and it went to failsafe due to many trees in your line of sight at that time, it started heading home then 2nd level battery will force auto landing. Amazing how it threaded that gap through the trees and glad you found it too.

Things to learn from the flight is flying try and avoid flying into the sun where it will blind you and lose sight of the phantom. What you could have done is gained altitude and then either used home lock or forced RTH for it to come back. Flying in thick trees will make it quite easy to lose range as 2.4ghz isnt great at penetration through lots of trees and the stock radio struggles quite a bit easily losing radio if you have a few big trees in your LOS a few hundred meters away.

jumanoc · Oct 1, 2013

Hey, IMO your phantom activated the RECEIVER ADVANCED PROTECTION FUNCTION, well described in Naza-M manual. Just read it and compare with your flight events. Pahntom didn't complete RTH because 2nd low voltage alert. Great recovery and on final descending prop guards saved your phantom from leaves :shock:

Rene75 · Oct 1, 2013

Thanx all for your posts.
I always wait for the 20 quick flashes before takeoff. So that should be alright.
Strange thing remains why it didn't respond when my Phantom lost signal with the RC. And I understand that it eventually landed itself due to the battery being empty. Which is a good thing btw

I've send the video to my supplier in the Netherlands and to DJI. Hopefully they have some insights about this flight. If I have some news I will post it here.

Happy and safe flights to you all

Cheers
Rene

UTR · Oct 2, 2013

In your video it definitely looks like the home point isn't set as you actually have control over the phantom when you move the controls (you just can't see it moving from the ground). When you pull back in HL mode the Phantom flies backwards exactly what it would do if the HL wasn't working. What I would say is that if you had GPS lock then plug your Phantom into your PC and check that IOC is enabled. If you have ever upgraded the firmware and had a compass calibration error the lack of a compass can disable the IOC. You need to recalibrate the compass and then connect it back to your PC and re-enable the IOC. Or the IOC switch will do nothing when you try to use it. You might have switched the switch in HL but the feature might not be on in your firmware meaning that you haven't actually switched in HL mode making your phantom just fly backwards in whatever direction it was facing when you pulled back rather than actually coming back to you.

Rene75 · Oct 3, 2013

Hi UTR

Thanx for your comment

IOS was not checked in the software. I haven't used that before, because I thought it was too complicated to use as a novice in the RC world.
I've found a good explanation about HL and CL on YouTube and will use it from this point on...

http://www.youtube.com/watch?v=BfcHlKcIshw

Regards
Rene

martcerv · Oct 3, 2013

UTR said:
In your video it definitely looks like the home point isn't set as you actually have control over the phantom when you move the controls (you just can't see it moving from the ground). When you pull back in HL mode the Phantom flies backwards exactly what it would do if the HL wasn't working. What I would say is that if you had GPS lock then plug your Phantom into your PC and check that IOC is enabled. If you have ever upgraded the firmware and had a compass calibration error the lack of a compass can disable the IOC. You need to recalibrate the compass and then connect it back to your PC and re-enable the IOC. Or the IOC switch will do nothing when you try to use it. You might have switched the switch in HL but the feature might not be on in your firmware meaning that you haven't actually switched in HL mode making your phantom just fly backwards in whatever direction it was facing when you pulled back rather than actually coming back to you.

This then likely shows the v4.0 permiter bug as Rene said in another post he had it set at 300m I think, when it gets stuck on the perimeter with the wind blowing it outside the zone it can get stuck there. The only way to get it off that spot is go to manual mode or failsafe by using the RTH switch or turning off the radio.