Miracle(s) or what?
1372 21 2018-10-28
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MuuSer
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I almost lost Air few days ago. At least there was a moment, when in my mind I already farewelled my cute drone.

So - can anybody explain behavior at 12 minutes and 18 seconds when RTH was invoked?

http://www.phantomhelp.com/LogViewer/EZHRBSPD9ABHAI94V7YV/

You may say that heavy wind is involved, but I don’t think so (there was almost no wind at shore), as if there were so heavy wind, then drone nose must be pointed to home anyway as it struggles to that point? Or am I wrong? And if you look at time to spent for passing distance from invoking RTH to that point, when returning to home really begins, then at least for me it is some kind of little miracle…

And another question. Why the hell drone in RTH holds height when flies to home point, instead of descending to RTH height and approaching to home point at same time? This behavior as seen in current log, is huge waste of energy as at heights there are almost always more windy…

And one thought more. The promised flying distance 2 kilometers in Europe is ridiculous and lie, as even in line of sight and in wild nature where is no other wifi signals, there are problems already after 300 meters.
2018-10-28
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JJBspark
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Hi,

Your miracle is the manual...

Your RTH was hampered by loosing connection, if out of control than the fail safe RTH starts.
Normally a user invoke RTH ; drone turns into the right direction and fly straight home.

Your second question ; Its safer to RTH at current altitude (must be reason for you to fly there at that height). If drone RTH and descends at the same time....mayby if will hit something as MA has no downward sensor.

But as an user you are free to lower height, just wait to have the good RTH bearing, cancel RTH and fly it yourself. (if there is a good connection ofcourse)
But your were lucky to get in back in time with 11% batt left after flying over water!

Happy many landings,
cheers
JJB
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hallmark007
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It’s amazing you can say there was no wind, you were flying at 1600ft how could you possibly know what the wind was like at that height. Your aircraft preformed just as it should and you were lucky to get it back. Thank your lucky stars because it wasn’t a pretty flight.
2018-10-28
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MuuSer
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JJBspark Posted at 2018-10-28 05:59
Hi,

Your miracle is the manual...

Thanks, JJBspark.

But I’m still confused. What did the drone between 12:18 and 13:14 of flying time, when I had invoked RTH. Yes – it lost connection for 17 seconds with remote, but why it decided to go to opposite direction towards the farthest point from home, it has been? Manual did not answer that. Or does?
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MuuSer
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hallmark007 Posted at 2018-10-28 06:28
It’s amazing you can say there was no wind, you were flying at 1600ft how could you possibly know what the wind was like at that height. Your aircraft preformed just as it should and you were lucky to get it back. Thank your lucky stars because it wasn’t a pretty flight.

Glad, you find it amazing, hallmark007, but I can say that video footage from that flight in SD card is flawless and amazingly stabile – not even slight interference from heavy wind. And 1 thing more – there is quite large difference about 1600ft and 1162ft height. Unfortunately my Mavic Air is not capable reach so far at least in EU standard of remote connection regulations.
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hallmark007
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MuuSer Posted at 2018-10-28 07:54
Glad, you find it amazing, hallmark007, but I can say that video footage from that flight in SD card is flawless and amazingly stabile – not even slight interference from heavy wind. And 1 thing more – there is quite large difference about 1600ft and 1162ft height. Unfortunately my Mavic Air is not capable reach so far at least in EU standard of remote connection regulations.

Sorry my bad, it was 1162ft, you did receive 7 high wind warnings.
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MuuSer
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hallmark007 Posted at 2018-10-28 08:05
Sorry my bad, it was 1162ft, you did receive 7 high wind warnings.

No problem at all. I just did not take them seriously enough as I know how sturdy can Air be. I have footages where there are quite heavily bended trees and “dancing” bushes around and Mavic Air makes very good job. True – it was not 100% stabile footage, but in this harbor – as I told – the video was flawless…
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JJBspark
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MuuSer Posted at 2018-10-28 07:53
Thanks, JJBspark.

But I’m still confused. What did the drone between 12:18 and 13:14 of flying time, when I had invoked RTH. Yes – it lost connection for 17 seconds with remote, but why it decided to go to opposite direction towards the farthest point from home, it has been? Manual did not answer that. Or does?

Hi MuuSer,

yes, its in the txt in the manual ( see my copy paste in my first post)

Your RTH > AC starts to turn towards home (the long way around, don`t know why), heading drone 217, home brg 182. (at 12m19.3s)
A signal loss 10 secs ; FailSafe RTH starts ; connected again AC at hdg 277
AC retraces its route, so its flying away from you....(doing according the manual)
At 13m12s AC turning towards home...and fly`s to home in one straight line.
So if you are in control (connected) and see this happens, cx RTH and fly back yourself.
If your are disconnected, well hope that there is ennough juice in the battery to make home without getting wet or lost.

cheers
JJB
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MuuSer
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JJBspark Posted at 2018-10-28 08:56
Hi MuuSer,

yes, its in the txt in the manual ( see my copy paste in my first post)

Ok – then we can just blame that “2 kilometers” promised distance between AC and remote control in Europe. You can be as cautions as you can (as I am), but never fly further than 250 meters with Air in Europe. Ridiculous.

One thing I don’t understand – when I invoke RTH then why it does not fly straight to home, even when connection with remote is gone afterwards. And also – sure I’m stupid, but I can’t understand, why the hell it flies away from home point when it loses the connection with remote?

Can somebody from DJI explain me that. Thanks.
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mavic2zoom-ch
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MuuSer Posted at 2018-10-28 09:47
Ok – then we can just blame that “2 kilometers” promised distance between AC and remote control in Europe. You can be as cautions as you can (as I am), but never fly further than 250 meters with Air in Europe.  Ridiculous.

One thing I don’t understand – when I invoke RTH then why it does not fly straight to home, even when connection with remote is gone afterwards. And also – sure I’m stupid, but I can’t understand, why the hell it flies away from home point when it loses the connection with remote?

I have a Mavic 2 and fly in the UK (so subject to the same restrictions).

I've no idea if the M2 is somehow better with the signal, but I've flown 1+km away in open areas without any reports of signal loss. Not sure it'd make 2km, but ...
2018-10-28
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Fly74
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That"s scary.  I would hate that.
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MuuSer
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mavic2zoom-ch Posted at 2018-10-28 12:16
I have a Mavic 2 and fly in the UK (so subject to the same restrictions).

I've no idea if the M2 is somehow better with the signal, but I've flown 1+km away in open areas without any reports of signal loss. Not sure it'd make 2km, but ...

Air and Spark use different connection mechanism between AC and controller then Mavic or Mavic 2. Accordingly specification, distance between controller and Mavic 2 in Europe can be 5000 meters, so you have long way to go. ;)

I have also Phantom 4 and for it promised distance is 1 kilometer and that is correct and doable.
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SBasso
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Funny enough these days I was flying and I lost connection with the quad.

I couldn't stop recording nor return it home.

My question is, would come back by itself? The manual says yes, after 20seconds, but from that day, I don't trust 100% on it.

After jumping , walking, I had control again and brought back.
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hallmark007
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MuuSer Posted at 2018-10-28 09:47
Ok – then we can just blame that “2 kilometers” promised distance between AC and remote control in Europe. You can be as cautions as you can (as I am), but never fly further than 250 meters with Air in Europe.  Ridiculous.

One thing I don’t understand – when I invoke RTH then why it does not fly straight to home, even when connection with remote is gone afterwards. And also – sure I’m stupid, but I can’t understand, why the hell it flies away from home point when it loses the connection with remote?

When your aircraft looses signal the failsafe is to take the route it last flew to find its way home, if it regains signal it will stop for 10 seconds waiting for controller to give next instruction if none is given after 10 seconds it will RTH on a direct route.
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MuuSer
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hallmark007 Posted at 2018-10-28 14:26
When your aircraft looses signal the failsafe is to take the route it last flew to find its way home, if it regains signal it will stop for 10 seconds waiting for controller to give next instruction if none is given after 10 seconds it will RTH on a direct route.


Okay, you talk about theory, but it is slightly dummy and dangerous. If I have pushed RTH and wanted to go it directly to home, then after that is very dangerous, if AC decides to do something else even if it loses connection with remote. Or is my opinion very wrong?

P.S.
And by the way – for me RTH button on Air remote controller newer worked. I must always use app button and slide by finger from left to right to invoke RTH. Already that is little annoying and can waste sometimes valuable seconds…

And I think that user invoked RTH must be priority even if connection lost. In first time when connection establishes, it must be invoked and after that we can cancel it, if we want…
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QuadFunAus
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MuuSer Posted at 2018-10-28 18:24
Okay, you talk about theory, but it is slightly dummy and dangerous. If I have pushed RTH and wanted to go it directly to home, then after that is very dangerous, if AC decides to do something else even if it loses connection with remote. Or is my opinion very wrong?

P.S.

I believe the idea behind the RTH taking the last flown route home during a loss of signal is that it knows this route is safe and obstacle-free.  Remember during a loss of signal you have no video transmission, so if there happens to be a large obstacle in a straight line between the drone and the controller,  obstacle avoidance would probably kick in and the drone would just stop and hover until it ran out of battery.  With no video feed or telemetry, you wouldn't know this is happening.  That's why once you regain signal, it stops so you now have an option based on video and telemetry.  
As for return RTH button, I believe you press and hold to activate RTH, not just a quick press.  At least that's what I remember from reading the manual when I first got the MA.  Unless loss of signal, I always fly home manual,  via VLOS, radar or map.
Hope this helps!
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MuuSer
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QuadFunAus Posted at 2018-10-28 21:21
I believe the idea behind the RTH taking the last flown route home during a loss of signal is that it knows this route is safe and obstacle-free.  Remember during a loss of signal you have no video transmission, so if there happens to be a large obstacle in a straight line between the drone and the controller,  obstacle avoidance would probably kick in and the drone would just stop and hover until it ran out of battery.  With no video feed or telemetry, you wouldn't know this is happening.  That's why once you regain signal, it stops so you now have an option based on video and telemetry.  
As for return RTH button, I believe you press and hold to activate RTH, not just a quick press.  At least that's what I remember from reading the manual when I first got the MA.  Unless loss of signal, I always fly home manual,  via VLOS, radar or map.
Hope this helps!

Yes, yes, QuadFunAus. You are right and I’m stupid. But what I want to say, is – if I made a decision that flying home is safe at RTH height and invoked a RTH, then whatever happens between AC and controller, it MUST to return (except when I cancel it) directly to home point, not activating failsafe return, as this can be dangerous as when battery energy lowers, it will anyway start directly to fly to home point and in this time there may be already obstacles in the way… But what I know – DJI is a god and god bless him or her blind followers…
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QuadFunAus
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MuuSer Posted at 2018-10-28 22:07
Yes, yes, QuadFunAus. You are right and I’m stupid. But what I want to say, is – if I made a decision that flying home is safe at RTH height and invoked a RTH, then whatever happens between AC and controller, it MUST to return (except when I cancel it) directly to home point, not activating failsafe return, as this can be dangerous as when battery energy lowers, it will anyway start directly to fly to home point and in this time there may be already obstacles in the way… But what I know – DJI is a god and god bless him or her blind followers…

IMHO, you should never rely on RTH unless you are in trouble.  If you need to get back fast, look at your radar, point the drone so the arrow is pointing to the home point and fly back in sports mode.  You can see the arrow, (your drone), getting closer to the home point and keep an eye on your distance from home, then you can tell when the drone is right above you.  You can also use your map in a similar way.

Key is to always check your distance from home and altitude, even when using RTH.  This way if your drone for some reason starts heading away from your home point, or starts to lose altitude, you will see via the telemetry.
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hallmark007
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MuuSer Posted at 2018-10-28 18:24
Okay, you talk about theory, but it is slightly dummy and dangerous. If I have pushed RTH and wanted to go it directly to home, then after that is very dangerous, if AC decides to do something else even if it loses connection with remote. Or is my opinion very wrong?

P.S.

If you lose connection then RTH will not work simply because you have no connection to the drone, it takes the route it flew as a failsafe, simply because it knows there was no obstacles on this route, as soon as it  regains signal it will allow controller to take another action if controller takes no action then it will return home.
2018-10-29
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MuuSer
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Ehh hallmark007, QuadFunAus and yours blue eyes. I give up. This is not conversation. You just repeat and repeat your mantra and not read at all, what I wrote.

I still don’t know why my drone made failsafe RTH as I invoked RTH myself and accordingly to app female voice it recognizes that and then flies away. Yes – maybe there was right after that (and there was) connection lost, but decide to fly away from remote controller and make longer (safer you say) way to home when battery is only 35% if anyway after remaining only 30% it anyway flies directly to home point, is idiocy.

We are not discussed here no one my suggestions to safety for that situation as occurred with my drone and when I was unable to do something as drone was from only 350-400 meters away and out of range.

There is always ways to make things better if you just can think out of box, but let it be. This is not that place…
2018-10-29
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Roundhouse_
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Is there even a EU country that allows for a altitude of more than 300 meters? sounds really like a crazy stupid thing to do to go this high with a drone
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hallmark007
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MuuSer Posted at 2018-10-29 03:08
Ehh hallmark007, QuadFunAus and yours blue eyes.  I give up. This is not conversation. You just repeat and repeat your mantra and not read at all, what I wrote.

I still don’t know why my drone made failsafe RTH as I invoked RTH myself and accordingly to app female voice it recognizes that and then flies away. Yes – maybe there was right after that (and there was) connection lost, but decide to fly away from remote controller and make longer (safer you say) way to home when battery is only 35% if anyway after remaining only 30% it anyway flies directly to home point, is idiocy.

It looks like when you pressed RTH your aircraft started to return home, you can see this in your log aircraft initially heading home, you then almost immediately lost signal, when signal returned, it looks like your aircraft went into failsafe RTH for loss of signal.

You will see at 7294 second =577ft from home
                           7310 second =574 from home
I beleive signal may have been lost for more than 3 seconds causing aircraft to go to loss of signal RTH
2018-10-29
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