How to use RTH correctly!

[Andy9]

Most of us have RTH set to the signal lost situation which is almost the only reasonable option.
But this may lead to wrong pilot actions.
When the signal is lost you loose all telemetry as well. So you actually can't be sure if the signal is lost or not. Maybe (which is more often) just down link is compromised and you have still the control. If the drone activates RTH by itself (and you don't know that) pushing the RTH button will actually cancel RTH and you may wait for the drone forever - a false flyaway situation. It will just waiting for the pilot action and land where t is when the battery goes below 10%. But if there is enough power to return it maybe activate RTH again. I'm not sure about that.
So what is the most reasonable action in situations when the screen turns grey?

 

[WV. Rootman]

I tend to lose video first. My first action is to make sure i'm in alignment to the drone, then I gain altitude to restore video feed. That is the situation most of the time. If that doesn't work, I hit the RTH on the Mobile. I calmly wait for the Rth to start. There was one time I had to wait awhile. It hasn't failed me yet. It has worked perfectly.
Maybe I didn't answer your question, but that is my experience on my mountain top.

 

[Meta4]

So what is the most reasonable action in situations when the screen turns grey?

If ever you are uncertain and want to ensure that your drone is returning, the thing to do is switch off the controller for half a minute.
That will definitely initiate RTH and get the drone flying back.

 

[Andy9]

Yes, that should be the right action. Thanks!

 

[3rdof5]

If you cancel RTH accidentally it will still re engage during a fly away when it again loses connection with the RC. That being said, I always have my RTH set to initiate in full auto mode, meaning any and all events that can trigger it will tell the AC to climb to the set RTH height and come home. The ONLY time I change that is if im flying in very tight terrain in which a lost signal could cause it to climb to the set RTH height and hit an overhead obstacle. In that case I set RTH mode to hover only. I will disable RTH completely when testing battery life so it will only autoland on critical battery. Hope this helps.

 

[John Locke]

There are some RTH nuances that I've noticed between Lightbridge and OcuSync. P3A, P3P, P4 and P4P use Lightbridge. Mavic2, Mavic Air 2 and P4P V2 use Ocusync. With Lightbridge, it's common to lose video feed, but still have craft control. The screen goes blank when that happens. I believe with P4P using Lightbridge they introduced a dialog that actually state in the app, DISCONNECTED, which means you have no control and the craft should auto trigger RTH. However you don't know that until the craft comes back into range to receive a signal, at which time you'll get a flight image showing the craft on it's way back, at which time I usually disable the RTH.

With OcuSync, I have noticed that in a situation where signal is getting weak, you get a warning of weak signal in the app, with a RED background to the text, along with a fuzzy video image. This is a clear warning before a disconnect is about to happen. At this time I usually stop flight motion and reassess my mission and position, along with my antenna direction if I'm using my windsurfer. If signal gets too weak for the image to be received, total disconnect immediately happens, and the app says so, "Disconnected" and the screen is blank. With Ocu-Sync I've never had a situation where you have control of the craft without video, which happens with P3P.. OcuSync craft simply doesn't allow flight control without video like earlier Lightbridge craft. As a result, with my OcuSync craft I pay more attention to the signal strength bars when range is sketchy. I tend to watch the signal strength bars like a hawk to mitigate surprise disconnects.

In sketchy flight routes where I anticipate possible signal loss, I always make sure my RTH altitude setting is adequate to clear surrounding objects, like mountains, buildings, wires, trees etc. My std setting is 300', but I've had to increase that in mountain areas a few times. If I ascend to altitudes higher than my RTH level, I make sure I never fly behind something that is higher of course. That's a recipe for disaster.

 

[David_Cambridge]

Like many other drone issues, there is no one “correct”response. There are many conditions that strongly influence the decision - flying under things, launching from a moving boat, etc. Flying drones, like real airplanes is an activity where the best action decision is a real time one which depends on these conditions. The aviation Concept of continuous situational awareness seems to be a much more useful and effective approach.

 

[cheddarman]

As in thread #2, increase altitude is always a good starting point. Most times loss of communication is due to weak signal due to obstruction of the radio signal. Climb up and regain line of sight coms.

 

[Andy9]

As in thread #2, increase altitude is always a good starting point. Most times loss of communication is due to weak signal due to obstruction of the radio signal. Climb up and regain line of sight coms.

Yes you're right but we are talking about signal lost and you don''t know if you still have uplink connection.

 

[cheddarman]

Surely if you've set things up correctly, on signal loss the drone will automatically enter RTH mode?
I also have low battery - below 20% - set to RTH but I start bringing the drone home myself at 30%

 

[Andy9]

Surely if you've set things up correctly, on signal loss the drone will automatically enter RTH mode?
I also have low battery - below 20% - set to RTH but I start bringing the drone home myself at 30%

OK, here is not the question about the battery status. Flying home at 30% tells nothing. It depends mostly of how far the drone is.