My new drone - "gone with the wind".

[albertly]

I know this is a forum about Mavic Drones. But my main question is “Could it possible to happen with Mavic Drones”.

Recently, I’ve bought Hubzan Zino Mini.

I wanted to check a flight range with a parabolic antenna.
I checked in a rural area - I couldn't properly check a range (was windy), however FPV feed was perfect (the receiver of Zino Mini on the back part, so when I fly back from a long range I have some minor glitches in video feed). In the case with a parabolic antenna when returning home there were no problems whatsoever.

I was very happy and excited - it seems to me that a parabolic antenna works. And I was eager to check a range in non-windy condition.
Yesterday at night there was no wind - perfect condition to fly (on my opinion and on opinion of "UAV Forecast").
So, I started to fly (in semi urban area - suburb). In the range of about 5 km I had an error - "The current environment has a lot of interference to GPS. Flying in attitude mode".

Some days before I've got the same error in the same area. However, I thought that it was minor hiccup - GPS was restored - everything was OK. I was a little bit worried about "GPS interference", checked the internet on the subject, not found something satisfaction - more on this later.

So, I thought surely the GPS would be restored, I have very strong signal – so be it – attitude mode, let's push a little bit forward.
My joystick was in forward position, the drone flew forward. The GPS was occasionally restored and occasionally weakened. I was not worried I went forward - signal was strong.

However, after a while, I lost connection with an error "Adjust your antenna ... ". What I do in such a case - I try to raise my controller up and move myself toward a drone direction as much as possible. Every time it worked, connection was restored and I pressed RTH.

Not in this case. I did everything I raised my hands up, I walked toward the drone about 300 m (it was as much possible I could). I should mention that all this time GPS was disconnected as well. I started to panic. What to do? To wait for the drone automatic RTH but no GPS. I waited about 10 min. The drone wasn't on the horizon. I turned the controller off in desperate hope that it might reconnect to the drone when I turn it on. No luck.

I tried to drive and looked for the drone in "last known location" - nowhere to be found.
In the morning I make a search of "last known location" with my other drone in that area. No luck. My new drone is gone.

About losing GPS signal, I've checked the internet, causes:
1. The sun activity - not my case - "UAV Forecast" said good to fly, at first my drone locked decent amount of satellites. The sun activity could not change so suddenly.
2. Interferences - The error I've got: "The current environment has a lot of interference to GPS" and many people mentioned this cause.
What BS is that. I drive my car in populated urban area, in traffic jumps - I do not lose GPS signal. What is there less interference? It is a mother of all interference. When I drive into a tunnel - yes, I do lose GPS signal - and it is obvious why. However, when I am out the signal is quickly restored and I am happy on my way.

The truth to be told, I did lose GPS signal of my car's built-in GPS (because I think my car's GPS is bad and cheap)
But I never ever ever lose GPS signal of my mobile phone.

If anybody knows what is the real cause of losing GPS signal?

Maybe it's just bad and cheap GPS module in Hubsan Zino Mini Pro?
Can it happen in DJI Mavic products?
Mavic products are thought to be far more reliable and higher quality (maybe next to Autel Evo drones)?
You guys mostly fly DJI drones. Have you experience problems with GPS signal?

P.S.
I am really frustrated. Maybe on the brink of giving up the hobby entirely. The possibility that 500$ or event 2000$ (in case of Mavic 3) just can fly away not so appealing to me.

 

[Lasidora]

You are a braver flyer than me, if I had had any message at 5km stating that "The current environment has a lot of interference to GPS. Flying in attitude mode".
I would have instantly rotated the drone 180 degrees and flew back like a bat out of hell, never to fly near that location again, it looks like after you lost GPS connection, the drone got to a point that forward momentum took it permanently out of RC range so no matter what you pressed on the controller, it would have done nothing, eventually due to drift etc due to no GPS, so no failsafe RTH, the drone battery would have depleted & it would have forced landed due to this.
Sorry for your loss, but it's an expensive learning curve, the Mavic series seems quite resilient to GPS lock loss, but even these are not infallible, keeping the drone within RC control range is the key so that the second this sort of error occurs, retrieval of the drone is still possible

 

[Phantomrain.org]

You had a very smart drone, Giving you all the warnings but you did not take real notice
Long distance flying is Risky not sanctioned and ignoring warning as you did is the cause of the loss.

You went 16,000 ft when you experienced a loss of GPS signal. The same day before you got the same thing .

Notice how I lost my GPS signal. I believe its related to the DJI programming of the Warning System in the software.

Phantomrain.org
Gear to fly in the Rain and Capture the Storm

 

[albertly]

You had a very smart drone, Giving you all the warnings but you did not take real notice
Long distance flying is Risky not sanctioned and ignoring warning as you did is the cause of the loss.

You went 16,000 ft when you experienced a loss of GPS signal. The same day before you got the same thing .

Notice how I lost my GPS signal. I believe its related to the DJI programming of the Warning System in the software.

Phantomrain.org
Gear to fly in the Rain and Capture the Storm

Yes, in hindsigh I should RTH or U turn on the first warning. However I had plenty of battery, very good signal. On previous day GPS was successfully restored. I thought it would be restored this time as well.

 

[Phantomrain.org]

Yes, in hindsigh I should RTH or U turn on the first warning. However I had plenty of battery, very good signal. On previous day GPS was successfully restored. I thought it would be restored this time as well.

Did you watch the video , can you tell me why I lost my GPS signal. ?

 

[albertly]

You had a very smart drone, Giving you all the warnings but you did not take real notice
Long distance flying is Risky not sanctioned and ignoring warning as you did is the cause of the loss.

You went 16,000 ft when you experienced a loss of GPS signal. The same day before you got the same thing .

Notice how I lost my GPS signal. I believe its related to the DJI programming of the Warning System in the software.

Phantomrain.org
Gear to fly in the Rain and Capture the Storm

My friend, you've never lost GPS signal. You have 26 satellites couldn't be better. You just had problems with FPV or control signal. It is pretty darn usual situation here. You still able to RTH or your drone is able. LOL

 

[Deleted member 103366]

@albertly if I understand you correcctly and you flew out to 5km from the controller, is it wise to fly so far beyond VLOS in Israel?

Phantomrain, I am curious what was going on with the battery in that flight or is the video a compilation of flights? At 4:33 it's 54%, at 4:59 77%.
Maybe I am being thick but it seems the only time the GPS count was low was during or just after a disconnection. Is that not expected due to no GPS count being reported to the App?
Where are the antennae in that drone? I am wondering why it seems the homeward leg was riddled with disconnections?

 

[albertly]

H

@albertly if I understand you correcctly and you flew out to 5km from the controller, is it wise to fly so far beyond VLOS in Israel?

Phantomrain, I am curious what was going on with the battery in that flight or is the video a compilation of flights? At 4:33 it's 54%, at 4:59 77%.
Maybe I am being thick but it seems the only time the GPS count was low was during or just after a disconnection. Is that not expected due to no GPS count being reported to the App?
Where are the antennae in that drone? I am wondering why it seems the homeward leg was riddled with disconnections?

Here is my flight log

 

[slup]

...Maybe it's just bad and cheap GPS module in Hubsan Zino Mini Pro?
Can it happen in DJI Mavic products?
... Have you experience problems with GPS signal?

Both Hubsan & DJI drones are man made, they will never be 100% reliable, that's why you always expect the worst & plan so the damage to people & property IF thing's fail, will be as small as possible.

The reason for your GPS acting up is obvious ... it was faulty. Flying up on 90m over a low built up residential area wouldn't normally interfere with the GPS reception at all.

...I am really frustrated. Maybe on the brink of giving up the hobby entirely. The possibility that 500$ or event 2000$ (in case of Mavic 3) just can fly away not so appealing to me.

To me it seems that you due to ignorance greatly contributed to the outcome & didn't had a clue about the risk you took when the GPS reception started to get wonky ... You flew well out of sight over a built up area & disobeyed the warnings you got. You were well aware about that you didn't had any GPS assisted horizontally hold ... but yet you continued your flight & when you lost the connection you thought that pushing RTH would make a difference & thought that the last known GPS position magically should lead you to your drone.

In reality your drone didn't have any means of knowing where you HP was ... it didn't have any horizontally hold, instead it was freely affected by all outside coming forces ... like wind. When you lost connection your drone either started to drift away into the wind direction & continued with that until the battery was depleted ... or it auto landed (that's how DJI drones are programmed ... if in ATTI mode & losing the RC connection they land on the spot).

 

[albertly]

Both Hubsan & DJI drones are man made, they will never be 100% reliable, that's why you always expect the worst & plan so the damage to people & property IF thing's fail, will be as small as possible.

The reason for your GPS acting up is obvious ... it was faulty. Flying up on 90m over a low built up residential area wouldn't normally interfere with the GPS reception at all.


To me it seems that you due to ignorance greatly contributed to the outcome & didn't had a clue about the risk you took when the GPS reception started to get wonky ... You flew well out of sight over a built up area & disobeyed the warnings you got. You were well aware about that you didn't had any GPS assisted horizontally hold ... but yet you continued your flight & when you lost the connection you thought that pushing RTH would make a difference & thought that the last known GPS position magically should lead you to your drone.

In reality your drone didn't have any means of knowing where you HP was ... it didn't have any horizontally hold, instead it was freely affected by all outside coming forces ... like wind. When you lost connection your drone either started to drift away into the wind direction & continued with that until the battery was depleted ... or it auto landed (that's how DJI drones are programmed ... if in ATTI mode & losing the RC connection they land on the spot).

The fault was mine. No doubt. However I hoped (based on previous experience) - Ok I am above the bad area with GPS interferences. Let's just pass that bad area and GPS would be restored. I had more than 60% battery and very good signal both video and control. The stupid thing I did was to hope a connection continue to be good. I should make U turn, but I didn't. I was perfectly aware that w/o GPS - no RTH of any kind. And the result is sad.

BTW, you said faulty GPS. My question is can GPS lost happen in DJI products. As far as I know DJI has 3 GPS systems: American GPS, Russian GLONASS and European Galileo. Hubzan has only first two. Does anybody have an experience of losing GPS signal "out of the blue" with DJI products?

 

[slup]

... My question is can GPS lost happen in DJI products.

Yes ... it's nearly always due to that a larger part of the sky is obscured or due to a rare HW failure. If it happens up on 90m height ... 99,99% HW failure.

 

[old man mavic]

@albertly any drone can lose GPS lock for a variety of reasons and as @slup said pressing RTH will not be of use ,as the drone has no reference point to know where it is when it is in atti mode
sadly it was a lack of experience and understanding of your drone that led to what happened to you

 

[eEridani]

Got too close to that radar installation, eh?

 

[albertly]

Got too close to that radar installation, eh?

No airport, no military base.
More interesting, I've checked now on the map. There is a drone/model planes school nearby only 200 - 500 meters from a place where I started to get "GPS problem". What a surprise! I've shocked. Maybe I should go there to learn to fly .

I've never heard that people have problems with GPS on their phones near radars. You know I live in Israel - a lot of military activities of all kind like "Iron Dome", etc.

I want to know what happened. I always fly far. That's my hobby - to fly far. I trusted GPS. With GPS - no matter what drone can always make RTH. And it worked perfectly well until yesterday. Yes, I am lacking experience.
So it's important for me to know what was wrong. Maybe bad quality of Hubsan.
I am looking for physical explanation why I can lost locked GPS. I sure "radar" and GPS work on different frequencies.

An electro-magnetic wave goes from above (satellite) into my drone on 90 m height w/o any obstacles. Very small data package, a few bytes of data should be transmitted, no package lost prevention needed (like UDP protocol). What physically can be wrong ?

The light from Sun is THE SAME electro-magnetic wave (different frequency of course, but exactly the same, we just able to see this frequency band, Sun is a transmitter, an eye is a receiver ) - there is no darkness w/o any reason - a cloud, a eclipse, Sun on the different side (night), etc.

I want to continue with this hobby. Maybe I need more quality product like Autel or DJI. I cannot afford 2000 backs fly away w/o any reason.

P.S.
And yes I push the limits I want to fly far regardless of local VLOS. I think VLOS restriction is BS. All racing and freestyle are done in goggles. Where exactly is VLOS there?

 

[albertly]

I've found the problem.

Hubsan Zino Mini Pro has faulty GPS. I wish I saw this video before.

Hubsan engineers knew about this problem.

Never ever ever Hubsan again​

Any chance to get my money back from Hubsan?

Hubsan Zino Mini Pro Gimbal Error and GPS Lost Fix​

 

[dave canada]

GPS is a good thing but not infallible. Even in remote places you can run into mag interference and the gps can be off the length of a football feild sensors go haywire altitudes are entirely different then what is read and if you are in a long distance run or short run these places take down any drone I know these things as fact after finding a third drone in the same area. like the one guy said get the hell out of there if you suspect anything at all I have a mavic pro that has been over a thousand miles and is for the most part is amazing how it always returns home but it only takes once and poff gone ! I got a marco polo locator becuase i,m such a hard head , since then i haven,t lost another drone but it took three days of climbing and cussin to find one in mountains becuase of mag interference and pushing the drones limits

 

[Zbip57]

Did you watch the video , can you tell me why I lost my GPS signal. ?

You lost your control signal, not GPS signal. The app was showing 26 or 27 GPS satellites when your controller signal was lost. The displayed satellite count drops to zero at that time only because the drone is incapable of transmitting the true count to the app whenever the control signal is interrupted.

Why the control signal was interrupted at that point is probably due to the trees between your balcony and where the drone was located at the time. There is no "Bermuda Triangle" mystery there. That can be easily proven by flying from an unobstructed location instead, like from the marina pier.

The other warnings in your video about the drone possibly not being able to return to home, despite having a solid GPS signal reception, has to do with the "Altitude Zone" which you're flying under for the Burke Lakefront Airport.

In this particular case, it would have been no problem as the Altitude Zone starts at a height of 150m. As long as you are flying lower than that, no problem. As long as your RTH height is configured to less than 150m (492ft), no problem.

But let's say, just for example, that you were flying at a height greater than 150m, on the far side beyond this Altitude Zone, when your control signal was lost. The drone would turn for Home and fly only until bumping into the outer edge of the restricted Altitude Zone and then be prevented from entering or crossing this GEO zone. It would hover there until running out of battery. That's what the warning is telling you.

Or, if you were flying under the 150m Altitude Zone when your control signal was lost, which you are allowed to do as shown in your video, and if your RTH height was configured to higher than 150m (492ft), upon loss of signal the drone would first try to climb to your configured RTH height before turning for Home. But on the way up it would bump into the 150m Altitude Zone ceiling. It would there be prevented from climbing any higher up into that GEO zone. Would it still turn for Home? I think not until reaching its configured RTH height, which it can't. Again it would hover there until the battery ran out. That's what the warning is telling you.

The warnings are connected only in so far as, depending on your current flying height and RTH height configuration, a loss of control signal may prove disastrous if you are flying near or under an Altitude Zone GEO restriction at the time.

In your video there was no problem at all. The drone had sufficient GPS lock, and was automatically returning home at a height of 350ft that was well below the 150m (492ft) Altitude Zone restriction.

The loss of control signal was almost certainly caused by the trees obstructing the signal. Rather than launching from your balcony and having a spotter in the marina in contact with you by cellphone, if you instead launch directly from the marina with a clear line of sight for your transmission signal, there would be no issue at all.

 

[Phantomrain.org]

Yes its a zone very close to the Geo Fence , and thus we can produce it every time we fly out, the difference is sometimes we can fly thru it , but if i hover in that area than I can get it to loose signal. Does not matter where we take off from.

If we pass thru to 8000 ft were fine but the Warning Set happens at 5000 ft . I will be making another video soon.

Phantomrain.org
Gear to fly in the Rain.

 

[GFields]

Sorry for you loss

 

[albertly]

I know these things as fact after finding a third drone in the same area.

At least now you have a golden field of drones or drone's honeypot or drones Bermuda triangle

Just kidding.

I am so sad and angry that it is only thing I can do now.
You've got a luck to find your drone.

How am I going to find mine in this area? The last known location is a roof of some kind of a greenhouse.
Every time I look at the map it seems to me than I can find it or search with my other drone (BTW, no GPS problems with the second one).
But when I drove there it is much worse than it looks from above - a lot of fences of private areas and houses.
Should I knock in every door asking "May I check your roof. My drone may be landed on it or maybe not"
Sounds ridiculous.

The first night I entered illegally that greenhouse to look through the roof ( you know "greenhouse I can see through a roof"). I thought, people sure would thought that I am a burglar and I thought about explanations I am going to give in local police and explain to police what it is "flyaway".

What is better needle in haystack or drone in Corn Maze



Very interesting how your mobile behaves on that "golden field" ?