DJI Drone Help Forum

Mavic 2 Pro zoom crashed

DJI keeps blaming me for events before the last 13 seconds before the crash, they say sensor was working great. Please let me know if sensor could have prevented the crash. Help please, my drone is gone and DJI is flip flopping on me… I think 13 secs was enough time for the drone only if the sensor was working fine.

https://drive.google.com/drive/folders/1z0SvYj5dORp6VQ5s7aO2u-PQFuQePr4g?usp=sharing

https://youtu.be/0OB5GioNjuc

Heres the flight:

https://www.phantomhelp.com/LogViewer/T6PQQZYBOHJFOOI2AE6U/

  1. While doing an orbit shot the drone flies into some trees: 10m 7.8s (QuickShot was interrupted. The aircraft will hover in place.; Upward Obstacle Detected)

  2. The pilot loiters around that area for ~2minutes (trying to get out of a stick situation?). Multiple collision avoidance warnings.

  3. At 12m 48.3s the pilot command the left stick to down position while VPS altitude at this point is 1.6feet. Drone initiates Forced landing.

  4. Pilot probably realizes the landing: left stick goes to neutral and right pitch stick full forward taking him out of the area. Note: Drone is still landing (loosing altitude)

  5. While flying back across the lake the drone keeps loosing altitude (drone is still in “Forced Landing” mode). It eventually goes for a swim with the fishes at 13m 5.6s.

Sorry for your loss my man. I would suggest you keep your drone in sight next time :confused:

1 Like

Sorry for your loss, but be aware that all obstacle avoidance capabilities of the drone are treated by DJI as safety enhancement features, and not guaranteed in any way by DJI, should they fail to prevent a crash, and will not be covered under the DJI warranty. However, if you recover the aircraft, it will be replaced under DJI Care policy, if you purchased it, subject to the first replacement fee of $119.

Durix Helix shot, the drone failed to account a very dense area of the forest and Operator had limited view across the lake, It was almost too late when drone force itself into the forest during helix mode. Operator slowly maneuver the drone for a safe exit. Please note that the landscape of the area is a steep slope hill which drone may have confused for a landing pad without fully scanning the entire area using 6 obstacle sensor capability. I had taken into account a very wide amount of room for the drone to perform its stunt as per map, I think it’s time for DJI to fully account a real world scenario where not all lands are flat, we’re not always right beside our drone to keep a full eye view but rather somehow rely on sensors capability as per promoted and advertised.

Most of us purchased the Mavic 2 pro because it is a model that is more capable than most and considered as consumer flagship model, we paid a much greater premium price for such security and if we are being told that you failed to hit the brake, then someone needs to go back on the drawing board and justify the premium price. I own the Mavic 2 Pro here and if it’s the lower class model with limited capability, I may have put it to rest. All i’m saying is if the sensor was indeed programmed and well put into work such as instant force landing disable when the UAV is in a cardinal direction motion, I mean 10 seconds would have been enough to apply such auto safety maneuver.

1 Like

I’d have to agree with them on that point. Between 10m 7.8s and 12m 49.3s, the aircraft auto braked numerous times to prevent from crashing into the trees.

The real problem started at 12m 50s. You had the throttle stick in the full down position while the downward sensors were detecting the ground was near. That combination enabled Forced Landing mode and made the aircraft auto land (as designed). Once you cleared the trees, you should have moved the throttle to the full up position to cancel the auto landing. Instead, you let the aircraft continue to descend into the water as you commanded it away from the trees at full stick forward. It appears you were close enough to see the aircraft descending.

1 Like

Hello msinger,

Here’s the problem, given I did not push the stick up for some reason as it may have been me focusing on trying to maneuver and work on exiting the drone away from the forest with complete hesitation to move the stick up due to the heavy forest branches and leaves around me. Please understand that if the drone 6 sensors were coded/engineered properly then it would have quite clearly scanned/detected that I am surrounded with heavy trees/branches and on a very steep "40-45% angle gradient being on the edge of a sloping hill down into the lake edge then an option to land would have been a clear no no. Also, force landing without an operator input while travelling at 30-40km/hr doesn’t seem like a well-coded auto landing parameter thus indicating a pure risky move. I think by simply applying a simple logical coding parameter rule that a drone should not be travelling at 30-40/km on Cardinal direction heading South-West while set on force landing. The last time I checked, I own a drone with no landing wheels not an RC airplane. Please let me know if you still feel that allowing a flying brick weapon at 40km/hr, sensors disabled while on force landing mode is something that DJI should be allowing thus violating tc.canada flying rules. If you ask me, I think what should have happened is, while on force landing, a proper setting of speed plus direction allows a clear detection triggering a violation, it should have instantly terminated the moving 40km/hr speed force landing within seconds and hover while reactivating the 6 obstacle sensor or should be left activated, warn the operator that force landing has been terminated and awaits full control. I don’t quite understand why DJI would disable the obstacle sensor while landing but that’s beside the point.

1 Like

Hello msinger,

Here’s the problem, given I did not push the stick up for some reason as it may have been me focusing on trying to maneuver and work on exiting the drone away from the forest with complete hesitation to move the stick up due to the heavy forest branches and leaves around me. Please understand that if the drone 6 sensors were coded/engineered properly then it would have quite clearly scanned/detected that I am surrounded with heavy trees/branches and on a very steep "40-45% angle gradient being on the edge of a sloping hill down into the lake edge then an option to land would have been a clear no no. Also, force landing without an operator input while travelling at 30-40km/hr doesn’t seem like a well-coded auto landing parameter thus indicating a pure risky move. I think by simply applying a simple logical coding parameter rule that a drone should not be travelling at 30-40/km on Cardinal direction heading South-West while set on force landing. The last time I checked, I own a drone with no landing wheels not an RC airplane. Please let me know if you still feel that allowing a flying brick weapon at 40km/hr, sensors disabled while on force landing mode is something that DJI should be allowing thus violating tc.canada flying rules. If you ask me, I think what should have happened is, while on force landing, a proper setting of speed plus direction allows a clear detection triggering a violation, it should have instantly terminated the moving 40km/hr speed force landing within seconds and hover while reactivating the 6 obstacle sensor or should be left activated, warn the operator that force landing has been terminated and awaits full control. I don’t quite understand why DJI would disable the obstacle sensor while landing.

1 Like

* *Also, force landing without an operator input while travelling at 30-40km/hr doesn't seem like a well-coded auto landing parameter thus indicating a pure risky move.* *
You received the notification of Autoland and the correct procedure is Full Throttle Up to cancel. The speed you were seeing was due to your full elevator input. The aircraft will not travel during autoland any other way. IMO this is not a programming or aircraft error. The aircraft did exactly what it was designed to do, and responded to your elevator inputs accordingly. Granted, there is no “perfect” OA that exists to my knowledge and it is up to the operator to stay away from such obstacles as much as possible. In your case you were flying in much too tight of a window for OA to catch everything. Consider your flight plans more carefully.

Do you find it normal to land a drone at speeds over 30/km per hour nose dive positions with sensors off?

Also, did you see the full lake map and considered it small?

Also, was there any operator input in the last 10 secs of landing or during force landing mode?

Yes, they could probably make that feature smarter so it’s able to work better. I was simply explaining what happened.

FYI, if you don’t want your drone to use forced landing mode, you can prevent it by disabling the “Landing Protection” setting in DJI GO.

To answer your question, Yes…

Can you tell me what time this is exactly? Sorry I am just learning to read logs.

Try this…

Edit to the last post…It is 786 sec…not 826…my error in the graph

I agree with you guys that the OP is 100% at fault for getting into that mess in the first place and completely fumbling the recovery afterwards. Clearly inexperienced with lack of understanding (or misunderstanding) of the actual capabilities of his aircraft.

However, not cancelling the forced landing sequence after the operator ordered the aircraft to fly linearly is simply poor coding by DJI and should be amended. Since when manual elevator input is a good idea during automated vertical landing? I can’t think of any scenario where this would be a good idea.

IMO, any automated control feature should be terminated (or paused) immediately after manual operator input is detected.

Agreed. However, every scenario possible cannot be possible for coding. Been there done that…

True, same.

This one though seems quite preventable though – in hindsight anyway. A simple state check and a pause routine.

The chances of this making it through the great corporate filter into future revisions is slim but if it does, the OP should be rewarded for uncovering a potentially fatal bug.

Good luck with that OP.

Out

You may have a point that every parameter is avoidable but I guess maybe it’s time for DJI to see how Skydio R1 auto braking system and scanning system plays. I did not buy a Mavic or Phantom, I bought a state of the art flagship Mavic 2 Pro with 6 sensors loaded capable of scanning 360 degrees and been crash tested over n over online.

If you think that they can’t figure how to stop a 40/km speed flying quadcopter about to smack you on a forward motion in the name of “Force Landing sequence” on a bright clear day with no wheels regardless what setting it’s on whether it’s user’s finger stuck on controller or auto force landing then maybe it’s time to pull these things off the shelf before such flying brick kills someone on low height altitude. It’s one thing to fly at that speed for at least 100 meters in height even if it’s auto landing, but 10 feet and below?

Here’s the if scenario anaylsis.

Set “Force Landing” - user requested to land.
Check following parameters.

If speed/altitude = 30+ km/hr+below 10feet then cancel imemdiately - Speed is too fast
If Direction = thrust forward at high speed plus altitude=10 feet and below = cancel immediately and hover
Cardinal direction, altitude too low which possible ground crash = cancel and hover

I can go and on and it ain’t rocket science to auto terminate auto landing when clearly the UAV is on a Cardinal direction travelling at a very high speed, after all we don’t really need to land a drone landing like a Boeing airplane do we?

I think Air transport safety for most countries might agree on me on this safety flaw.

We’ve already established that the automated landing logic could be better.

You now need to acknowledge the mistakes you’ve made as the operator/pilot.

You mean trying to maneuver the drone out of that dense forest while i’m well over 150 meters away relying on my cell video? The whole thing started with that drone shoving it into the forest depth. I am doing my best to get around those branches and leaves plus flying on a slope hill.

If that drone had done a wide scan during helix mode where I initiated much further away in the middle of an open lake, it would have easily take into consideration and terminate helix mode before flying itself right into the forest and let the user know too many obstacles.

If you wish, we can also dig down and discuss the helix mode fault and how it can be made better. I was there and you were not, this lake is well over 4 square kilometers open wide. It’s not hard for the sensor make an exception where if obstacle diameter is far too small then it must account that this is not possible for helix mode to continue as it requires an even wider space. I find it concerning that you are very well fixated with my action like blaming a Tesla driver for not keep their hands on the steering wheel tight enough.