All good things come to an end. Epic RTH Fail

KeithS · Mar 28, 2016

mikeve said:
Sorry for your loss.

Is the bird well enough to recover the DAT file. That would tell a more complete story.

No luck I'm afraid. Connected it to my PC tonight and no sign of any connection possibility what so ever. Just a loud beeping sound from the drone when I power it up and that's it.

Meta4 · Mar 28, 2016

KeithS said:
No luck I'm afraid. Connected it to my PC tonight and no sign of any connection possibility what so ever. Just a loud beeping sound from the drone when I power it up and that's it.

You have to enter flight data mode in the app to be able to connect.

KeithS · Mar 28, 2016

Thanks Meta4- seems as through too damaged internally. Can't get a connection to the controller via the app. I'll pull it apart over the next few days and do a more thorough diagnosis.

With The Birds · Mar 28, 2016

When RTH kicks in I resist the temptation to touch anything until I am sure I have a solid connection.

rich146 · Mar 28, 2016

Go back to exactly where you stood when flying the quad ( sorry I can't call them birds ! More like flying bricks lol ) . Look around and work out what could cause interference

Sent from my iPhone using PhantomPilots mobile app

KeithS · Mar 29, 2016

ferraript said:
without DAT log we can only speculate about what happened in those 10 seconds between 8:18:55.565 and 8:19:05.051
but I have one possible explanation:
I can see several throttle inputs from RC in your TXT log in that time 8:18:55.565 and in the 2-seconds period before this time (while Phantom was already returning home)
maybe this interrupted the bird from ascending and it then started to fly directly to you (at this moment it was at 58.9 m height) and crashed directly into that building

in the user manual, there is written:
"Aircraft will stop ascending and immediately return to the Home Point if you move the throttle stick if the aircraft reaches 20 meters (65 feet) altitudes or beyond during Failsafe."
that would confirm my explanation

Hi Ferraript.

I've gone through the printed documentation that was provided with my P3P and havent been able to find the quote you mentioned. Can I ask where did you find it written?

I've checked both the Quick Start Guide and the Safety Guidelines and Disclaimer booklets.

Meta4 · Mar 29, 2016

KeithS said:
I've gone through the printed documentation that was provided with my P3P and havent been able to find the quote you mentioned. Can I ask where did you find it written?
I've checked both the Quick Start Guide and the Safety Guidelines and Disclaimer booklets.

It's disturbing that you don't mention the Manual which should be the place to look for technical information.
Go to: https://dl.djicdn.com/downloads/phantom_3/en/Phantom_3_Advanced_User_Manual_v1.6_en_160225.pdf
.. and you'll find the manual. There's also a copy in the app.
RTH is a critical section of the manual and there are three pages explaining it.
Mid-way down p15 you'll find that section.

KeithS · Mar 29, 2016

Meta4 said:
It's disturbing that you don't mention the Manual which should be the place to look for technical information.
Go to: https://dl.djicdn.com/downloads/phantom_3/en/Phantom_3_Advanced_User_Manual_v1.6_en_160225.pdf
.. and you'll find the manual. There's also a copy in the app.
RTH is a critical section of the manual and there are three pages explaining it.
Mid-way down p15 you'll find that section.

Thanks for that, I'm very **** with things like books and manuals, in the way I keep them and read them. This booklet didn't come with my P3P, just 2 other more abbreviated booklets, and the RTH Section doesn't mention this in the abreviated version. But ignorance is no excuse. Thanks for the lesson, and no doubt other's who've also missed it will thankyou too.

moto_jw · Apr 2, 2016

It's too bad that this happened. Not moving the sticks during RTH is a good thing to remember. This could have easily happened to me if I wasn't thinking about it.

Jojoned · Apr 2, 2016

Is it possible that "motor obstructed" could mean you hit a bird, a real flying kind of bird...you would never see it. I would think they would avoid the drone, but maybe?

ddh1313 · Apr 2, 2016

This is a really interesting thread that everyone should take in. I will almost always be on the throttle or yaw controls as a disconnect RTH occurs. It's not because I am freaking out or misunderstanding what's happened, rather simply trying to gain altitude or spin a bit to get signal back. It NEVER occurred to me that in the process I could potentially be cancelling out a pre-determined RTH height requirement.

pomonabill220 · Apr 2, 2016

Sorry to hear of the loss!
I did read about RTH being cancelled if ANY stick input is given.
It was buried though and only was in the online manual.... It might be a good idea to mention this in the printed docs that come with the bird (brick) though.
Still, sad to hear of the loss! Hope you get flying again soon!

noki49 · Apr 2, 2016

ferraript said:
without DAT log we can only speculate about what happened in those 10 seconds between 8:18:55.565 and 8:19:05.051
but I have one possible explanation:
I can see several throttle inputs from RC in your TXT log in that time 8:18:55.565 and in the 2-seconds period before this time (while Phantom was already returning home)
maybe this interrupted the bird from ascending and it then started to fly directly to you (at this moment it was at 58.9 m height) and crashed directly into that building

in the user manual, there is written:
"Aircraft will stop ascending and immediately return to the Home Point if you move the throttle stick if the aircraft reaches 20 meters (65 feet) altitudes or beyond during Failsafe."
that would confirm my explanation

I think that part of the manual is badly written or poorly translated, and you have misinterpreted it.
I believe it is only relevant when within 20m of your home point.
This is better clarified by the next part of the manual.

Meta4 · Apr 2, 2016

View attachment 49326[/QUOTE]

Jojoned said:
Is it possible that "motor obstructed" could mean you hit a bird, a real flying kind of bird...you would never see it. I would think they would avoid the drone, but maybe?

In this case (and most others), motor obstructed indicates the crash.

Meta4 · Apr 2, 2016

noki49 said:
I think that part of the manual is badly written or poorly translated, and you have misinterpreted it.
I believe it is only relevant when within 20m of your home point.

ferraript was quite correct.
The 20 metre issue you refer to is something different
Look a little further down the page to the last section of this extract from the manual - it's quite clear.

John Decker · Apr 2, 2016

Add me to the list of people who somehow missed that! Good to know. Sorry it cost you your drone.

GadgetGuy · Apr 2, 2016

A few things to consider. If the RTH is triggered by a total signal loss after 3 seconds, and not by the pilot pressing the RTH button on the transmitter, no stick input can be registered by the aircraft to alter the prerecorded RTH settings recorded on the aircraft before launch, until signal is restored.

Therefore, if the stick input was received by the aircraft, you had control again, and should have been using full throttle up to recover from the RTH, and immediately cancelled the RTH by pressing once briefly on the transmitter RTH button. If you then, again, lost full signal for 3 seconds, RTH would engage again, and you can repeat the process, as necessary to regain full manual control. If the app is ever asking you if you wish to cancel RTH, you have full manual control again, and should cancel, to avoid the very problem you encountered.

The goal of RTH is to regain signal control. It worked, but you didn't cancel it and take over. You are always smarter than RTH, once you have control again.