A friend recently managed to obtain a Mavic Pro from the local Apple store.  He is an experienced UAV pilot who has owned two P3 aircraft as well as a P4.  We are both extensively experienced with Litchi missions.  The bird was updated to the latest firmware, & the RC, compass, & IMU were properly calibrated.  On Wednesday 11/23/16, after several manual test flights, he sent his Mavic Pro on a Litchi test mission.  He was using the latest iOS version of Litchi.  The results are discouraging & in fact rather alarming.  Video of the flight is attached.  The mission was a 37,500' non-stop @ 30 mph & the Mavic was out of RC contact for most of the mission.  Upon reviewing the video it was discovered:

* Horizon tilt is horrible during the mission.
* The gimbal experienced repeated "hiccups" throughout the flight.
* Twice during the mission the bird inexplicably stops, alters altitude, & wanders about.
* The Mavic nearly lands itself into the harbor & nearly crashes into Pier #2.
* It is amazing that the Mavic was not lost.
* Upon viewing the video the pilot became so disenchanted he immediately packed up & returned the Mavic.  Unfortunately he did not download the flight log.

Viewing the attached video my take is the bird either lost satellite signal (doubtful) or entered ATTI mode.  The latter has been reported by numerous Mavic pilots.  This often seems to occur even when the bird is locked on 10+ satellitess.

WARNING - Not sure if this is a single defective unit, or a general hardware, firmware, SDK, or Litchi issue, but exercise GREAT CAUTION when flying the Mavic with Litchi.

Ha hahahahahah   an you were just worried about the horizon tilt and a some glitches,    wow !    with over a 1,000 Wifi boosters below you and that christmas tree of Antennas stuck on top of the trans building, you were lucky it wasnt fried,   and yeah TBH  if you send it back now before the hobby is banned completely it will help a lot of other people.

MikeQView Posted at 2016-11-25 19:47
Ha hahahahahah   an you were just worried about the horizon tilt and a some glitches,    wow !    wi ...

Mike - Phantom 2/3/4 all fly fine over the same area.  Nothing to do with Wi-Fi but thank you for your "intelligent" response.  {:4_177:}

WOW !   Honestly !   the route has been done before!  well i gotta say its a serious testiment to the systems that have been flown, i gotta say i would not have entrusted any model i have previously ever owned to that arduous route,  i have only just come to the DJI camp,  i now fly an inspire 1 v2.0 and hopefully a Mavic once it arrives, and lots of FPV race quads,   in years gone by all my models had APM of one sort or another, i have set missions but NEVER with the precision hover that close to the water,  and all the concrete and steel around,  the pilot has "balls of steel" my friend !  the P4 mission plan was well thought from a results perspective,  and many sections of that were beautiful, i seriously had no idea of its capabilities, i have come from old skool, i understand if the craft behaves well to location precision there is no reason for it not to be capable, but to seeing it done is something else,  so for the planning and setting of the mission i must take my cap off.

MikeQView Posted at 2016-11-25 20:24
WOW !   Honestly !   you have done the similar route before !  well i gotta say its a serious testim ...

DJI aircraft are generally extremely reliable & precise.  Precise enough you can program multiple birds & rely on them to complete the mission as created (see attached video - a pair of P3 Standards executing a joint Litchi mission).  This mission has been flown 100+ times & your Inspire would perform this flight just as well, though it might cut it close on the battery run time.  It is the behavior of the Mavic that prompted me to issue the warning.  The Mavic is not performing up to DJI's usual level.  I wish my friend would have saved his flightlog.

I think the point is that these devices, although precise and capable, are still just civilian RC aircraft toys.  They are not subject to the same safety checks and control that heavier than air flying things are.  Any aircraft that can carry humans over densely populated areas like this are highly controlled.   While you may be experienced, these are still very fallible devices.  Its this kind of activity that will result in bans pretty much everywhere.  Yes they are small, but speeds are high and the odds of one augering in due to plastic parts or various consumer grade components is pretty darn high.

Cwood Posted at 2016-11-25 13:59
I think the point is that these devices, although precise and capable, are still just civilian RC ai ...

this. DJI shouldn't have named it 'PRO' because its setting false expectations. Its a consumer drone, not a professional platform.

All very impressive videos. A bit risky, but impressive.

Cwood Posted at 2016-11-25 21:59
I think the point is that these devices, although precise and capable, are still just civilian RC ai ...

The point of the topic is to alert Mavic pilots of potential issues when flying Litchi missions.  These failures may occur ANYWHERE.  It isn't a debate over where & how to fly.

I've already lined up some Litchi missions for my Mavic to fly...when it arrives.  That's a worry.

Shill Slayer Posted at 2016-11-25 10:08
The point of the topic is to alert Mavic pilots of potential issues when flying Litchi missions.   ...

Are you sure that it's Litchi itself and not something else? Have you tried doing the waypoints through the GO app with better success?

That is one amazing flight.  Some of the problems may be due to conditions on that day. I am new to Litchi and have never done urban flying like that but I could see that local winds around some of the buildings could have shaken the Mavic beyond the gimbal's ability to compensate. Combine that with signal loss and possible interference, and I think the Mavic did amazingly well considering the possible conditions on that day.  Has the P4 has flown that same mission multiple times?  

I've seen his videos. Very impressive. I'm very disappointed he didn't stick with it and try to trouble shoot this with the developers of Litchi to figure out the problem. If it wasn't Litchi's fault, I'm sure they could have at least figured out the problem so DJI could fix it.  The Mavic is my first drone. I've got the Litchi app but I guess I'll wait awhile to use it.

Thank you for the warning and I appreciate you sharing.  I hope your good deed doesn't come back to bite you, there are at least 3 part 107 violations in that video.  

Now you say Mavic with Litchi missions, have you flown the same Mavic with DJI GO app? Did you get the same results.  To me it sounds more like an issue with the Mavic that the apps? I could be wrong, still waiting for my Mav.

More than likely a Litchi issue, have them try a mission in the GO app to see if it works just fine or has similar results.
And remember, if the aircraft would have been lost more than likely they would have had to purchase another one.
The warranty would cover an issue if the aircraft was sent in and a by analyzing the flight records the crash was due to a malfunction. But without the aircraft, no logs can be analyzed and more then likely there would be no warranty.

I have flown my Mavic 4 times using the Litchi app yesterday. All autonomous waypoint missions. No issues at all. I'm using S7 Edge.

I wonder how long this kind of thing will remain legal.

flipside Posted at 2016-11-25 21:13
I wonder how long this kind of thing will remain legal.

until someone causes an accident and / or someone dies because of it.

devGOD Posted at 2016-11-26 03:33
until someone causes an accident and / or someone dies because of it.

Yep.       .

Interesting

* Twice during the mission the bird inexplicably stops, alters altitude, & wanders about.
Did a Litchi mission (Android) wiith mine earlier today. Previous mission went perfectly so was gaining confidence in Android Litchi.  

Todays mission was curved turns along about a 4nm route. Nothing special at all. No POIs. Just fly the circuit.
Started mission, Mavic took off, flew perfectly to WPT1 and on toward first turnpoint at WPT2. Cruising at 50kph. However as it past the WPT2 it declerated from 50kph to 0 over about 10 seconds for no apparent reason.  So now just hovering uncommanded.  Still connected to remote as it was only about 400m away.

At this point I had a problem as the Mavic was drifting downwind at ~ 2mph, off shore - out to sea! Already over the ocean. Wind blowing ~ 20kts!  Tried various actions to regain control and bring it home.  After a disconcerting 5min as I watched live feed of my unresposive machine heading out to sea, with the battery decreasing. Exacebated by in the back of my mind knowing I had set RTH alt up at 350 AMSL, due terrain along the route. If I hit RTH and it climbed up there 20kt, offshore breeze could easily be double this, and not be able to progress into it.  Anyway eventually I got it into RTH mode and it came home.  

Puzzled as to why it stopped moving mid route though.  Have all the logs and video and am Chasing it up with the Litchi support guys. Will see if I induced it somehow, or if Litchi did threw a wobbly.  

Is flying this way even legal?

Just wondering.

Here in Australia CASA would hunt you down and throw the book at you.

Logger Posted at 2016-11-26 13:20
Interesting

* Twice during the mission the bird inexplicably stops, alters altitude, & wanders abou ...

Glad you recovered and the aircraft returned home.
Remember, if the aircraft is lost and you are using a 3rd party app there's no way for DJI to review flight logs and you would probably have to purchase another aircraft.
Have you ever had an issue with the GO app ?

Homerlovesbeer Posted at 2016-11-26 14:06
Is flying this way even legal?

Just wondering.

I think it is legal. So long as it is in Line of site on your own private property. Following the SOCs. Cannot see the problem. At least it was supposed to stay on my property until Litchi went haywire or I stuffed something up sending it offshore.

DJI-Ken Posted at 2016-11-26 14:07
Glad you recovered and the aircraft returned home.
Remember, if the aircraft is lost and you are u ...

Remember, if the aircraft is lost and you are using a 3rd party app there's no way for DJI to review flight logs and you would probably have to purchase another aircraft.
Have you ever had an issue with the GO app ?

Yep was aware of the risks wrt warranty.  No issues with the GO app or DJI. It has been great. Just adding another cautionary tale wrt Litchi.

I am putting this down to either operator error, Litchi or environmental conditions. Not sure how Litchi deals with envelope limits vs planned route. But I did set a fast cruise speed of 50kph and tried to fly a route in a strong Cross wind of 40kph wind. Something had got to give. Maybe the aircraft could not roll sufficiently to maintain track and programmed speed simulataneously. Slowing down and stopping was probably a form of failsafe.  I also understand the Mavics low battery RTH sits beneath Litchi, so if I had done nothing, it may well of eventually kicked in and come home. Would have been a stuggel into the wind though and was not game to wait as it could easliy have been at 1/2 a mile off shore in another 15 minutes of drifting downwind.  

My plan was to fly the full route on a calm day. Today I just wanted to fly the first miinute of it, to see if Litchi would actually get up to planned speed 50kph then return home and do some other stuff with DGI Go. But I was thwarted by the mission failing and it blowing off course..

was VPS on? Could this be a case of the mavic forward sensors getting confused due to the suns light hitting the forward sensors at a bad angle?   There have been a few posts where the mavic goes dumb at 150 feet, and acts like there is something infront of it. At the same time, it looks like maybe VPS is what saved the quad from running in to that pier.. anyway, that flight was awesome!

trance728- Posted at 2016-11-25 23:27
Are you sure that it's Litchi itself and not something else? Have you tried doing the waypoints th ...

I can not say with 100% absolute certainty that this was not a Litchi issue.  I can say that I have flown HUNDREDS of extremely complex Litchi missions with Phantom 2/3/4 aircraft & I have NEVER experienced such behavior from any of these other DJI model aircraft.  Twice during this flight the Mavic clearly seems to have lost its position.  From 4:20-5:55 & again from 11:00-15:00 the bird is simply wandering about on its own.

WolfgangStiller Posted at 2016-11-25 23:52
That is one amazing flight.  Some of the problems may be due to conditions on that day. I am new to  ...

Winds were only 6 mph during the flight.  If you go to 3:25 in the video you can see the flag atop the Schaefer building for an idea of the winds.  Observe the flag in the Mavic video to the other two videos for comparison.  These missions have been flown without incident over 100 times with Phantom 3 & 4 birds.  I have flown similar missions in winds over 15 mph without issue.

Daveman Posted at 2016-11-26 04:29
Thank you for the warning and I appreciate you sharing.  I hope your good deed doesn't come back to  ...

We aren't 107 pilots but thanks for the heads up.

DJI-Ken Posted at 2016-11-26 05:19
More than likely a Litchi issue, have them try a mission in the GO app to see if it works just fine  ...

Ken - I have flown HUNDREDS of Litchi missions with Phantom 2/3/4 aircraft & NEVER experienced anything like the Mavic in this video.  From 4:20-5:55 & again from 11:00-15:00 the Mavic has clearly lost its position & is almost certainly in ATTI mode.  It is rather disconcerting when your bird decides to go on walkabout!  

The reason my friend returned the Mavic was exactly because of what you state.  Without the aircraft there would be no warranty & the pilot would have to repurchase a new Mavic.  The Mavic in this flight appears to have been trying to become lost & it is extremely fortunate it eventually regained satellite lock & returned.  I do wish my friend had extracted the log from the aircraft before he returned the bird.

No Man's Drone Posted at 2016-11-26 06:01
I have flown my Mavic 4 times using the Litchi app yesterday. All autonomous waypoint missions. No i ...

If I may ask how intensive were your Litchi missions?  I mean to say there are missions & then there are missions.  If you are running a simple mission of relatively short duration you may not experience an issue.  OTOH if you are flying a 7+ mile mission with 75+ waypoints there is a lot more time for a fault to become evident.

Logger Posted at 2016-11-26 13:20
Interesting

* Twice during the mission the bird inexplicably stops, alters altitude, & wanders abou ...

Sounds very similar to what was experienced during my friends flight.  I am glad you retained the logs.  My suspicion is you will find the Mavic dropped to ATTI mode & that is why she stopped & began to drift.  Check your logs to see if my hunch is correct?  Also if you find it did drop to ATTI mode note how many satellites it is showing locked.  I ask this because I have seen other reports of Mavics dropping to ATTI mode while having plenty of satellites locked.

Homerlovesbeer Posted at 2016-11-26 14:06
Is flying this way even legal?

Just wondering.

This is NOT a discussion about rules or legality, etc..  It is a discussion about potential issues flying Litchi missions with a Mavic.  The reported issues could occur ANYWHERE.

ZeeinBC Posted at 2016-11-26 18:16
was VPS on? Could this be a case of the mavic forward sensors getting confused due to the suns light ...

VPS was enabled while OA was disabled (to achieve the 30 mph mission speed).  As you can see from the video it was a totally overcast day.  No issues of the sun confusing the OA sensors.

fansebeed138 Posted at 2016-11-26 04:29
Now you say Mavic with Litchi missions, have you flown the same Mavic with DJI GO app? Did you get t ...

Yes he flew several uneventful test flights with the Go app prior to the Litchi test.  Like you I am still waiting for my Mavic for almost two months now.  {:4_173:}

it really looks likely that it's environment issues (e.g., sudden winds/downdrafts or electronic interfere)  to me. I have flown a number of very complex (deliberately complex to test this out) way point missions now with Litchi and Mavic with absolutely spot-on results.

WolfgangStiller Posted at 2016-11-26 12:57
it really looks likely that it's environment issues (e.g., sudden winds/downdrafts or electronic int ...

Upon what are you basing this assertion?  There is no significant wind (6 mph), & numerous DJI aircraft have flown similar missions over the same area HUNDREDS of times.  How did wind or environmental issues cause the Mavic to stop & hover aimlessly for 2 & 4 minutes respectively?  

Wow. The pilot doesn't like the app and he ships the Mavic back? Bit of a drama queen I think.

Homerlovesbeer Posted at 2016-11-26 01:06
Is flying this way even legal?

Just wondering.

Can't say for all countries, but it is definitely breaking the laws in US or Canada. Operator must maintain line olf sight and there is no way that could have been done on that flight.

Logger Posted at 2016-11-26 00:34
Remember, if the aircraft is lost and you are using a 3rd party app there's no way for DJI to revie ...

If the GO app is working properly and a 3rd party is not, then it's something with them or their use of the SDK.