Water Crash... Is this the VPS issue im now reading about?

[ChasiTail]

Been flying my mavic around on my 5acre open field since I bought it a couple months ago. No issues ever, everything worked as advertised.

So I thought it was time to take it out on the boat and get some shots of the boat. Everything was going as planned for about 10 minutes of flight. I was in Active Track for much of the time, following the boat around.

I exited that mode, to get video of the boat driving under the drone as it hovered, and that's when things seemed to go sideways. The drone on its own flew up from about 25' elevation to 150', then went into "forced landing" where I could not stop the descent with the stick, or pause or by canceling it on my screen. As it was coming down, I was able to use the RT stick to fly it close to the boat where it splashed into the water. Luckily I was also able to keep the props spinning and kept it on the surface long enough for us to somehow catch the drone with a gaff and retrieve it into the boat. The last minute or so of flight data was the drone going crazy on the surface of the water as I kept the joysticks pinned up praying the drone didn't sink.

I was perplexed as to what happened, and have since been reading about the VPS issue over water, so I uploaded my flight record and sure enough, just before my mavic went crazy on its own, the VPS went from reading correctly, to reading 0.0-0.7 feet, even when the drone climbed on its own from 25' up to 150'. VPS stayed the same, all the way back from 150' to just as it almost hit the water.

Heres my flight log. What do you all think?
Phantom Log Viewer - PhantomHelp.com

 

[Bunny Too]

Been flying my mavic around on my 5acre open field since I bought it a couple months ago. No issues ever, everything worked as advertised.

So I thought it was time to take it out on the boat and get some shots of the boat. Everything was going as planned for about 10 minutes of flight. I was in Active Track for much of the time, following the boat around.

I exited that mode, to get video of the boat driving under the drone as it hovered, and that's when things seemed to go sideways. The drone on its own flew up from about 25' elevation to 150', then went into "forced landing" where I could not stop the descent with the stick, or pause or by canceling it on my screen. As it was coming down, I was able to use the RT stick to fly it close to the boat where it splashed into the water. Luckily I was also able to keep the props spinning and kept it on the surface long enough for us to somehow catch the drone with a gaff and retrieve it into the boat. The last minute or so of flight data was the drone going crazy on the surface of the water as I kept the joysticks pinned up praying the drone didn't sink.

I was perplexed as to what happened, and have since been reading about the VPS issue over water, so I uploaded my flight record and sure enough, just before my mavic went crazy on its own, the VPS went from reading correctly, to reading 0.0-0.7 feet, even when the drone climbed on its own from 25' up to 150'. Stayed the same, all the way back from 150' to just as it almost hit the water.

Heres my flight log. What do you all think?
Phantom Log Viewer - PhantomHelp.com

Man, you are one darn agile, lucky, gifted individual.
Regards,
-d.
Edit - do you have powerball in your area?

 

[Egika]

Switching the Sports mode switch on the right of the remote is said to cancel auto landing.

 

[ChasiTail]

Switching the Sports mode switch on the right of the remote is said to cancel auto landing.

So Ive read... Would have been nice to know that a few days ago, BEFORE this happened! Guess I needed to spend more time on here reading other horror stories instead of out flying

 

[Andrew F]

My condolences for your experience. I haven't read your logs as there are others who do that so much better than me. But it seems you went into RTH which would not happen purely because of the often touted VPS water problem. But yes, for future reference, switching to sport mode "should" stop the auto landing sequence. I just flew for hours over the ocean and never had a VPS glitch including quite a few close water encounters. But I have not "upgraded" the firmware to .05 specifically for fear of encountering that VPS bug.

 

[bigirb2002]

Switching the sport switch does stop autoland. Tested it myself

 

[Andrew F]

So Ive read... Would have been nice to know that a few days ago, BEFORE this happened! Guess I needed to spend more time on here reading other horror stories instead of out flying

Not at all. You shouldn't have to read horror stories. DJI has made a HUGE mistake by disabling the stick controls during auto landing. Not your fault at all. Hopefully they are listening and will fix sooner than later. As for the RTH behavior, that's what it does when it loses signal and what it "should" do. The question is what initiated your RTH? Many people accidentally hit that button either on the controller or the screen. Was your controller making the beep beep sound?

 

[Glen e]

If it sounds exactly like the bottom VPS being a problem. This is what it does when It can't read that right distance on the water. I don't think I'll ever understand why the programmers have anything THAT commands the drone to complete an operation of any sort but you can't cancel it. There's a pause button on the front of the RC, it should work for EVERYTHING.

 

[Egika]

Not at all. You shouldn't have to read horror stories. DJI has made a HUGE mistake by disabling the stick controls during auto landing. Not your fault at all. Hopefully they are listening and will fix sooner than later. As for the RTH behavior, that's what it does when it loses signal and what it "should" do. The question is what initiated your RTH? Many people accidentally hit that button either on the controller or the screen. Was your controller making the beep beep sound?

Actually I doubt that many people hit this button accidentally. Where do you get this information from?
The physical button you need to press and hold for 3s. The screen button requires an additional slide to confirm the RTH function.
Hard to do this accidentally...

 

[bigirb2002]

Forgot to mention they fixed it in the firmware they just released u can now cancel autoland with the stick again

 

[Robbyg]

It certainly looks like that it was the VPS system.
You are one lucky guy, that it is not sleeping with the fishes

I can see when battery system was under severe stress and it seems like a lot of systems started to crash. I have never seen a log of the systems getting flooded with water.

Can you please please upload the 400mb+ DAT file to a file sharing service so we can see in more detail what happened.
I am going to contact BudWalker because he is the Jedi Master of Log file analysis. I think he will want to personally look at this one. At the very least you will get a very good report of what happened and the community will gain some useful info.

Rob

 

[ChasiTail]

My condolences for your experience. I haven't read your logs as there are others who do that so much better than me. But it seems you went into RTH which would not happen purely because of the often touted VPS water problem. But yes, for future reference, switching to sport mode "should" stop the auto landing sequence. I just flew for hours over the ocean and never had a VPS glitch including quite a few close water encounters. But I have not "upgraded" the firmware to .05 specifically for fear of encountering that VPS bug.

Never pressed RTH. Where do you see that at? I see "forced landing". Also wouldn't RTH have had it fly back to the homepoint at the start of the flight and not fly straight down?

 

[Bunny Too]

Looks like something happened at 09:05, you would have to upload the. DAT file to learn more.
Regards,
-d
And you are missing 5.3 seconds at 12:16:04. Weird.

 

[Egika]

Btw: the Mavic manual clearly states under "Flight Environment Requirements":
"3. Avoid [...] bodies of water"

 

[msinger]

Your Mavic was ascending on its own because the downward sensors were detecting the ground. When you moved the throttle stick to the full down position to counteract that automatic ascent, that caused the Mavic to switch to forced landing mode (since the downward sensors were still detecting the ground). As noted above, toggling sport mode on/off would have cancelled the forced landing. If you had the "Landing Protection" setting disabled, that would have prevented both of those issues from occurring.

 

[Andrew F]

Never pressed RTH. Where do you see that at? I see "forced landing". Also wouldn't RTH have had it fly back to the homepoint at the start of the flight and not fly straight down?

I'm referring to the sudden climb to height. I only know that to occur during an RTH subroutine. Sorry, I haven't been able to look at your log.

 

[Cerberus]

Forgot to mention they fixed it in the firmware they just released u can now cancel autoland with the stick again

Can anyone confirm what he said? and is he talking abour the .550 firmware update?

 

[PaoloOne]

Been flying my mavic around on my 5acre open field since I bought it a couple months ago. No issues ever, everything worked as advertised.

So I thought it was time to take it out on the boat and get some shots of the boat. Everything was going as planned for about 10 minutes of flight. I was in Active Track for much of the time, following the boat around.

I exited that mode, to get video of the boat driving under the drone as it hovered, and that's when things seemed to go sideways. The drone on its own flew up from about 25' elevation to 150', then went into "forced landing" where I could not stop the descent with the stick, or pause or by canceling it on my screen. As it was coming down, I was able to use the RT stick to fly it close to the boat where it splashed into the water. Luckily I was also able to keep the props spinning and kept it on the surface long enough for us to somehow catch the drone with a gaff and retrieve it into the boat. The last minute or so of flight data was the drone going crazy on the surface of the water as I kept the joysticks pinned up praying the drone didn't sink.

I was perplexed as to what happened, and have since been reading about the VPS issue over water, so I uploaded my flight record and sure enough, just before my mavic went crazy on its own, the VPS went from reading correctly, to reading 0.0-0.7 feet, even when the drone climbed on its own from 25' up to 150'. VPS stayed the same, all the way back from 150' to just as it almost hit the water.

Heres my flight log. What do you all think?
Phantom Log Viewer - PhantomHelp.com

I'm not much of an expert but I can see that at 8m 45s the IMU altitude is 23.3ft and the VPS altitude is 17.4ft and at 8m 50s suddenly the VPS altitude drops to 0.7 ft but the IMU altitude raises at 24.6 ft, then at 8m 55s you can see how the VPS reading goes crazy to 22.6ft and two seconds after it reads 0.7ft again. I think that from that moment onwards the VPS readings confused the drone and any descent was interpreted as a landing.

 

[Andrew F]

Your Mavic was ascending on its own because the downward sensors were detecting the ground. When you moved the throttle stick to the full down position to counteract that automatic ascent, that caused the Mavic to switch to forced landing mode (since the downward sensors were still detecting the ground). As noted above, toggling sport mode on/off would have cancelled the forced landing. If you had the "Landing Protection" setting disabled, that would have prevented both of those issues from occurring.

So if he hadn't done down stick, would it just have continued to climb until it reached maximum altitude? What a horrible glitch!

 

[Egika]

I'm referring to the sudden climb to height. I only know that to occur during an RTH subroutine. Sorry, I haven't been able to look at your log.

The Mavic will also rise if it detects an obstacle with the downward sensors.
Since the downwards sensors are known to be affected by water (or snow) it looks like the sudden gain in altitude was caused by the sensors.