Failsafe after 3 seconds?

[FredzMaxxUAV]

I did a flight today and lost signal (too far away). Not a problem, as according to the manual failsafe should kick in within 3 seconds and the aircraft should return home. It however took almost 4 minutes before the failsafe kicked in. I had "no signal" and could not control the aircraft - no speed/altitude indicators were available.
Any reason why this could take so long? Was there some remaining connection that I could not see that prevented failsafe? Should I switch off the RC completely when it takes too long?
P3 Pro with firmware 1.1.9 and DJI Go 2.30 (iOS).

 

[bobmyers]

You probably lost video and had a strong rc signal which may have delayed it. Did you initiate the RTH or wait for the controller to initiate it?

Did you get it back-- or do you know that it wasn't flying back during that 4 minutes -- it may have already initiated and was returning -- if you had no video, you would not know this.

 

[FredzMaxxUAV]

I got it back. There was no RC or HD signal, at least according to the app. I could not move the bird; at least I think, because in the app there was N/A everywhere in telemetry. So, yes, maybe I could have moved it without the app seeing it, but I did not try. It really is hovering for 4 minutes on the video, after which it turns around and initiates the failsafe RTH.
Would switching off the RC have helped? I was afraid that after I switch off the RC, and then switch it back on, it would have a harder time "finding" the bird again.

 

[bobmyers]

I got it back. There was no RC or HD signal, at least according to the app. I could not move the bird; at least I think, because in the app there was N/A everywhere in telemetry. So, yes, maybe I could have moved it without the app seeing it, but I did not try. It really is hovering for 4 minutes on the video, after which it turns around and initiates the failsafe RTH.
Would switching off the RC have helped? I was afraid that after I switch off the RC, and then switch it back on, it would have a harder time "finding" the bird again.

Did you try to initiate RTH with the button on the transmitter? Press and hold a bout 3 seconds.

If you turn off the transmitter, it will Initiate the RTH, but you shouldn't do that except to test the RTH when you have the P3 in sight. Always use RTH--

 

[FredzMaxxUAV]

Did you try to initiate RTH with the button on the transmitter? Press and hold a bout 3 seconds.

No, I actually did not. I thought that it would automatically failsafe from the moment No Signal appeared and the telemetry was gone from the app for more than 3 seconds, as described in the manual. What you are saying is that, although the app displayed No Signal and no RC and no telemetry, there might have been "some" connection to the drone? But wouldn't then there be an RC signal displayed in the app?

 

[BigAl07]

Keep in mind that the "Ap" is part of a system connected by a wire. The tablet/phone might have lost connection to the aircraft but the Tx was still in full control/contact with the aircraft.

 

[RodPad]

Doesn't the remote start beeping and flash red when you loose remote signal. I thought my Standard did. I think the bird was still receiving the remote.

Have you played back the flight log?

If you upload your log file to Healthy Drones, you get some interesting info, still figuring it out.

 

[bobmyers]

No, I actually did not. I thought that it would automatically failsafe from the moment No Signal appeared and the telemetry was gone from the app for more than 3 seconds, as described in the manual. What you are saying is that, although the app displayed No Signal and no RC and no telemetry, there might have been "some" connection to the drone? But wouldn't then there be an RC signal displayed in the app?

Did the app say no signal? Down load the data to Healthy Drones- and you will be able to see what transpired.

 

[FredzMaxxUAV]

In the flight log there is a 5 minute gap, it goes from 05:05 to 10:48. In healthydrones, that gap is also there...

 

[bobmyers]

In the flight log there is a 5 minute gap, it goes from 05:05 to 10:48. In healthydrones, that gap is also there...

Sounds like it got lost in the 4th dimension-- strange

 

[RodPad]

Yes, very strange,
But the app is recording the flight,
I guess the thought of playing back the flight was a nowhere.

 

[Meta4]

I did a flight today and lost signal (too far away). Not a problem, as according to the manual failsafe should kick in within 3 seconds and the aircraft should return home. It however took almost 4 minutes before the failsafe kicked in. I had "no signal" and could not control the aircraft - no speed/altitude indicators were available.
Any reason why this could take so long? Was there some remaining connection that I could not see that prevented failsafe? Should I switch off the RC completely when it takes too long?
P3 Pro with firmware 1.1.9 and DJI Go 2.30 (iOS).

You lost video signal - but still had a proper radio signal and could have flown or initiated RTH.
Your Phantom was just hovering, waiting for you to do something.
Because it still had signal, it did not return until Low Battery RTH initiated.
RTH is a very important system to understand.
There are two pages about it in the manual.
All owners should practice using RTH so that when/if they need it, they know how to set it and how it works.

 

[bobmyers]

You lost video signal - but still had a proper radio signal and could have flown or initiated RTH.
Your Phantom was just hovering, waiting for you to do something.
Because it still had signal, it did not return until Low Battery RTH initiated.
RTH is a very important system to understand.
There are two pages about it in the manual.
All owners should practice using RTH so that when/if they need it, they know how to set it and how it works.

Ah yes-- I knew you would have the correct answer, no RTH with lost video-- only lost rc signal.

 

[FredzMaxxUAV]

You lost video signal - but still had a proper radio signal and could have flown or initiated RTH.
Your Phantom was just hovering, waiting for you to do something.
Because it still had signal, it did not return until Low Battery RTH initiated.
RTH is a very important system to understand.
There are two pages about it in the manual.
All owners should practice using RTH so that when/if they need it, they know how to set it and how it works.

Before I post, I read the manual.
The app showed NO video signal, NO RC signal, NO telemetry. So one could assume there was NO connection. That's what I thought. But even with NO RC and NO telemetry, what you're saying here, is that there was, somehow, a connection? In any case, it took 5 minutes before the failsafe RTH kicked in.

 

[Meta4]

Before I post, I read the manual.
The app showed NO video signal, NO RC signal, NO telemetry. So one could assume there was NO connection. That's what I thought. But even with NO RC and NO telemetry, what you're saying here, is that there was, somehow, a connection? In any case, it took 5 minutes before the failsafe RTH kicked in.

That's the most logical explanation. If you did not have RTH set in the app set for hover in place, on losing signal it would have automatically initiated RTH.
But you generally lose video signal before radio signal.
You lost video signal, hence having no telemetry etc but there was still enough radio signal that the Phantom happily sat there waiting for you to drive it.
Video signal isn't necesasry for controlling the Phantom and you can pull the plug on the tablet and still have full control.
How far out was it?

RTH is one of the most important points of Phantom flying and the manual has two whole pages on it.
Every pilot should experiment and practice with RTH so that when/if you need it or it initiates automatically, you understand what's going on.
Also practice cancelling and resuming control.
Go out to a nice open area, send your bird out 100 feet or so and try using the app, the controller button and switching off the controller to see how it handles RTH.

 

[FredzMaxxUAV]

Meta4. Thanks for your insight. The app showed I lost video and RC signal, and telemetry. So I just supposed I couldn't move the bird anymore, and didn't try. It was quite far out as well.
So, when this happens again, even when the app is "dead", I would still try to drive the bird, correct? And if that doesn't work, should I switch off the RC? I suppose, with the RC switched off, the bird would start failsafe RTH within 3 seconds?

EDIT: flew another one in the same circumstances. And indeed, NO SIGNAL in the app, no telemetry, no HD or RC signal in the app. RC controller LED is red. But when I press and hold the RC controller's RTH button, the bird reacts and comes back.
Is this a bug in the app, or some other bug, or is it just designed this way?

 

[Pluto88888]

Meta4. Thanks for your insight. The app showed I lost video and RC signal, and telemetry. So I just supposed I couldn't move the bird anymore, and didn't try. It was quite far out as well.
So, when this happens again, even when the app is "dead", I would still try to drive the bird, correct? And if that doesn't work, should I switch off the RC? I suppose, with the RC switched off, the bird would start failsafe RTH within 3 seconds?

EDIT: flew another one in the same circumstances. And indeed, NO SIGNAL in the app, no telemetry, no HD or RC signal in the app. RC controller LED is red. But when I press and hold the RC controller's RTH button, the bird reacts and comes back.
Is this a bug in the app, or some other bug, or is it just designed this way?

Mine bird did the same thing yesterday night was out around 1800 Metres controller light was in RED with no HD so I just push the RTH button on the RC controller can back without any issues.

 

[BigAl07]

Meta4. Thanks for your insight. The app showed I lost video and RC signal, and telemetry. So I just supposed I couldn't move the bird anymore, and didn't try. It was quite far out as well.
So, when this happens again, even when the app is "dead", I would still try to drive the bird, correct? And if that doesn't work, should I switch off the RC? I suppose, with the RC switched off, the bird would start failsafe RTH within 3 seconds?

EDIT: flew another one in the same circumstances. And indeed, NO SIGNAL in the app, no telemetry, no HD or RC signal in the app. RC controller LED is red. But when I press and hold the RC controller's RTH button, the bird reacts and comes back.
Is this a bug in the app, or some other bug, or is it just designed this way?

You're missing the connection (or lack there of) between Ap and Transmitter. Look at it like this...

A) You have a Visual Aspect (Ap.Tablet) that allows you to see what is happening to the aircraft.
B) You have a Physical aspect (Transmitter) where you can actually control the aircraft.

The above systems are completely independent of each other. (A) is for pleasure and (B) is for necessity.

The AP is simply getting information and displaying it. Even without the Ap (without the tablet) you can still completely fly the aircraft. For whatever reason (loss if video signal, flaky connection between tablet and Transmitter or anything) your losing the "Visual" aspect of the flight. It's not a bug but could be indicating something in the connection (cable etc) isn't working. It could also simply mean you have interference (building, trees, conflicting signals from local WiFi etc) and you simply need to be aware of this and try to not get into the same situation or find a way to resolve it.

Remember you most likely still have FULL control of the aircraft you just don't have the benefit of the Ap on the tablet holding your hand so you need to react accordingly to get the aircraft back in signal or back heading home so you can see and control. Keep in mind that the tablet/Ap doesn't control the aircraft and can show no signal/no connection with the aircraft hovering safely 10' in front of you. Test it out while in a safe hover pull the cable and see how you still have full control of the aircraft. This is why Line-Of-Sight flying is so important to the FAA. I'm not taking one side or the other but this is a classic example of why they are pushing LOS only.

As stated above you need to really get a feel for the aircraft and any "non-standard" modes and procedures. RTH is a great feature but you've got to understand it and the aircraft intimately or it will just add confusion and complexity to a fairly simple system.

Good luck and Safe Flying

 

[FredzMaxxUAV]

Thanks BigAl07. I understand what you write. Isn't it odd, though, that you can still fully control the aircraft, but have no information on the app display, not even telemetry? Have more users had this? Mind you, this only happens at great distances - I never have this problem flying within 1 or 2 miles. Maybe it's because my firmware is old (1.1.9)? I already swapped cable and devices and this doesn't change anything.

 

[RodPad]

Think of basic RC systems. They never sent information back to you. You flew it, if you lost sight of it, you could loose it.

With the craft programmed what to do on lost remote signal, or if you loose sight of it and it is still receiving remote signal. You can press the RTH button to tell it to RTH. All done without information needed to be displayed to you. Your are controlling with the remote transmitting, your craft is receiving your commands. The craft is sending / transmitting data back to you and through the mobile app. Two different antenna systems, frequencies and technologies.

I learned from this that remote light turning red is now caused by lack of data from the craft.