FORCE LANDING ?!

[msinger]

Ed209, your latest log shows a similar pattern. Here's what I see:

• You moved the throttle (RC.throttle) to the full down position (-10000) when the Mavic was at an altitude (OSD.height) of 57.1 meters
• The Mavic descended down to an altitude of 41.8 meters in 3.5 seconds
• At 41.8 meters, the Mavic stopped descending (even though the throttle was still in the full down position) and the downward sensors (OSD.sWaveHeight) started reporting they were detecting the ground
• 0.5 seconds later, the flight mode changed to Forced Landing and the Mavic started to auto land

I'd suggest you send this log to DJI support too. Something does not seem to be working as expected.

 

[Ed209]

Ed209, your latest log shows a similar pattern. Here's what I see:

• You moved the throttle (RC.throttle) to the full down position (-10000) when the Mavic was at an altitude (OSD.height) of 57.1 meters
• The Mavic descended down to an altitude of 41.8 meters in 3.5 seconds
• At 41.8 meters, the Mavic stopped descending (even though the throttle was still in the full down position) and the downward sensors (OSD.sWaveHeight) started reporting they were detecting the ground
• 0.5 seconds later, the flight mode changed to Forced Landing and the Mavic started to auto land

I'd suggest you send this log to DJI support too. Something does not seem to be working as expected.

Wow msinger that's pretty compelling. I knew something wasn't right. I will reach out to DJI and report the issue. It is recoverable when it happens but the first time, when I was over water, scared the crap outta me. For anyone else, just full throttle up when it happens.

 

[F6Rider]

This is why I love this forum.... Very interesting reading, I do recall reading where DJI recommends turning off downward sensors over water, but this last occurrence happened over land. Glad I will now know how to react if this happens to me.

 

[Ed209]

This is why I love this forum.... Very interesting reading, I do recall reading where DJI recommends turning off downward sensors over water, but this last occurrence happened over land. Glad I will now know how to react if this happens to me.

I always had them off with my P3 and I am soon to be turning them off for good on the Mavic. They are good for newbs or as a precaution when flying in tight spaces but if you're confident at the sticks they become more intrusive.

 

[Marty Markoe]

Technically, DJI Care does not cover anything that results from water damage--even if water damage were to occur following the original problem. Even still, I purchased the protection. For your reference, here is a list of the exclusions:

Had the same problem several months ago. Lost signal going under small bridge and recovered P4 from shallow water. Using DJI Care, sent in for repair (replacement) but told water damage not covered and needed to send $1099.00 for repair. After reading Care contract saw lost signal is covered. Lost signal caused water contact and thus lost signal caused water damage.

Email and phone support was useless. Tech Support claimed only they could contact Repair support, not the customer. They never got back, only received another bill for payment. Finally emailed sales explaining problem. Did not hear back from them but several days later a replacement was sent. Within package was bill for $1099.00. Of course did not pay and checking remaining balance the Care contract did not and still does not show amount was deducted from remaining coverage.

Truthfully, I never expected to see the phantom for return. However, I suggest that persistence is what paid off.

Marty

 

[kmaluo]

I always had them off with my P3 and I am soon to be turning them off for good on the Mavic. They are good for newbs or as a precaution when flying in tight spaces but if you're confident at the sticks they become more intrusive.

I tried it off as well, but you really have to watch your landings. I've had a couple hard bouncing ones when I come in aggressive. I turned it back on, just gotta remember to turn it off over water.

 

[F6Rider]

I tried it off as well, but you really have to watch your landings. I've had a couple hard bouncing ones when I come in aggressive. I turned it back on, just gotta remember to turn it off over water.

You come in aggressive to land?? I always flair out at about 30' and let it settle gently to a landing. Don't want to knock the camera or gimbal out of alignment.

 

[kmaluo]

You come in aggressive to land?? I always flair out at about 30' and let it settle gently to a landing. Don't want to knock the camera or gimbal out of alignment.

Yeah, I'm a 3D heli flyer so I have some bad drone habits. But even hovering a foot of the ground, you can make it bounce if you're not feathering the sticks.

 

[F6Rider]

Yeah, I'm a 3D heli flyer so I have some bad drone habits. But even hovering a foot of the ground, you can make it bounce if you're not feathering the sticks.

Why I always hand catch when I can, but didn't have a problem with bouncing in manual landings, but I don't like them as the prop wash throws up to much FOD.

 

[Ed209]

I tried it off as well, but you really have to watch your landings. I've had a couple hard bouncing ones when I come in aggressive. I turned it back on, just gotta remember to turn it off over water.

I'm quite used to the bouncy landings from the P3. I flew with everything off all day today and no issues. The landings are still more controlled than a P3.

 

[quesoburgesa]

Had the same problem several months ago. Lost signal going under small bridge and recovered P4 from shallow water. Using DJI Care, sent in for repair (replacement) but told water damage not covered and needed to send $1099.00 for repair. After reading Care contract saw lost signal is covered. Lost signal caused water contact and thus lost signal caused water damage.

Email and phone support was useless. Tech Support claimed only they could contact Repair support, not the customer. They never got back, only received another bill for payment. Finally emailed sales explaining problem. Did not hear back from them but several days later a replacement was sent. Within package was bill for $1099.00. Of course did not pay and checking remaining balance the Care contract did not and still does not show amount was deducted from remaining coverage.

Truthfully, I never expected to see the phantom for return. However, I suggest that persistence is what paid off.

Marty

Exactly- they can't cover faults to the aircraft, and then not cover damage directly caused by the fault that precipitated the damage. So, it's irrelevant whether the craft landed in water or flew into the side of a tree. Had there not been a fault in the first place, there would've been no damage. It's pretty disgusting (and probably illegal) for DJI to try to weasel its way out of covering the repairs. They might be able to make impressive products, but they fall short in numerous other areas.

It's this type of unethical behaviour that makes me question how badly I want to give them any money at all...

Sent from my HTC_0PJA10 using MavicPilots mobile app

 

[Ed209]

Exactly- they can't cover faults to the aircraft, and then not cover damage directly caused by the fault that precipitated the damage. So, it's irrelevant whether the craft landed in water or flew into the side of a tree. Had there not been a fault in the first place, there would've been no damage. It's pretty disgusting (and probably illegal) for DJI to try to weasel its way out of covering the repairs. They might be able to make impressive products, but they fall short in numerous other areas.

It's this type of unethical behaviour that makes me question how badly I want to give them any money at all...

Sent from my HTC_0PJA10 using MavicPilots mobile app

Unfortunately, it's one of the negatives with DJI. I have read of instances where DJI covered claims after some back and forth. I think that if you have a legitimate claim and can prove it, especially if you show that you know what you're talking about and back it up with logs, they will cover it. I've read of that. The thing is, NOBODY comes close to DJI. Lightbridge/Occusync set DJI apart from everyone else. If I went with some inferior brand, I would be doubting that decision over and over.

 

[Ed209]

Happened a 3rd time again today. This time with all nannies off and at 400ft. I'll be sending all 3 logs to DJI this evening.

 

[BudWalker]

There was another poster that couldn't calibrate the VPS. The problem was a piece of transparent tape covering part of the sensor. I'm assuming you've looked for dirt, etc in the sensor?

 

[Ed209]

There was another poster that couldn't calibrate the VPS. The problem was a piece of transparent tape covering part of the sensor. I'm assuming you've looked for dirt, etc in the sensor?

VPS is calibrated and no warnings on any of the sensors. I took a close look at each sensor and don't see anything on them. They look clean as a whistle too.

Just got done with DJI Support Chat and they want me to send it in. I offered to send them all 3 log files. I am not going to send this in yet. Since I can get out of the force landing I know what to do. I am not sure if this is just my problem or a firmware issue but I'm not sending this out just yet.

 

[Chase R]

VPS is calibrated and no warnings on any of the sensors. I took a close look at each sensor and don't see anything on them. They look clean as a whistle too.

Just got done with DJI Support Chat and they want me to send it in. I offered to send them all 3 log files. I am not going to send this in yet. Since I can get out of the force landing I know what to do. I am not sure if this is just my problem or a firmware issue but I'm not sending this out just yet.

Had the identical thing happen last night. I was up a couple hundred feet then descended straight down for about 10 seconds. Saw an Warning message for "Optical sensors will be disabled when landing. Land with care." a few seconds before it happened. It was dark so I figured it didn't see the ground. Maybe some bug in the assisted land/downward sensor code??

 

[Ed209]

Had the identical thing happen last night. I was up a couple hundred feet then descended straight down for about 10 seconds. Saw an Warning message for "Optical sensors will be disabled when landing. Land with care." a few seconds before it happened. It was dark so I figured it didn't see the ground. Maybe some bug in the assisted land/downward sensor code??

Definitely an issue. I have all sensors disabled now anyway.

 

[chippie]

Had the identical thing happen last night. I was up a couple hundred feet then descended straight down for about 10 seconds. Saw an Warning message for "Optical sensors will be disabled when landing. Land with care." a few seconds before it happened. It was dark so I figured it didn't see the ground. Maybe some bug in the assisted land/downward sensor code??

Not sure this is a bug. You received a warning that the optical sensors will be disabled. It was dark, the optical sensors do not work when it is dark, nothing to focus on. However the sonic sensors would still have worked as you physically got closer to the ground. They do have a limited range though.

 

[Chase R]

Not sure this is a bug. You received a warning that the optical sensors will be disabled. It was dark, the optical sensors do not work when it is dark, nothing to focus on. However the sonic sensors would still have worked as you physically got closer to the ground. They do have a limited range though.

I was a couple hundred feet up when it took over. Pressing the red cancel button on the screen wouldn't stop it. It finally kicked out of auto land when I went full up on the left stick. Got my heart pumping a little bit. Ha

Reviewing my log, it looks like that warning came on right when it went into auto land. I'm thinking it falsely "saw" the ground but thought it was just too dark to read correctly. It must have some chunk of code that says "if stick is full down for x # of seconds and downward sensors "see" the ground, then auto land."

This is fine because most of the time the drone will land within a second or two so you wouldn't have time to cancel anyway but in this situation, there was a lot of time before landing. I'd guess the code displays the cancel button (which it should) but disables the button to keep users from accidentally canceling thinking it has to land cause its very close to the ground.

This very same situation could be created when landing above your takeoff location with bad lighting conditions so DJI can't add a clause to the code to disable if at a certain altitude. Really only "fix" here is to get the vision sensors to not read false positives.

I'm gonna calibrate the vision sensors then never hold the left stick 100% down for any period of time ever again. Lol

 

[chippie]

I was a couple hundred feet up when it took over. Pressing the red cancel button on the screen wouldn't stop it. It finally kicked out of auto land when I went full up on the left stick. Got my heart pumping a little bit. Ha

Reviewing my log, it looks like that warning came on right when it went into auto land. I'm thinking it falsely "saw" the ground but thought it was just too dark to read correctly. It must have some chunk of code that says "if stick is full down for x # of seconds and downward sensors "see" the ground, then auto land."

This is fine because most of the time the drone will land within a second or two so you wouldn't have time to cancel anyway but in this situation, there was a lot of time before landing. I'd guess the code displays the cancel button (which it should) but disables the button to keep users from accidentally canceling thinking it has to land cause its very close to the ground.

This very same situation could be created when landing above your takeoff location with bad lighting conditions so DJI can't add a clause to the code to disable if at a certain altitude. Really only "fix" here is to get the vision sensors to not read false positives.

I'm gonna calibrate the vision sensors then never hold the left stick 100% down for any period of time ever again. Lol

Ah ok, I did not read it correctly and did not realise it actually went into auto land. I thought you just received the warning message. I am sure all these things will be ironed out in future updates. I would pass the logs etc. onto DJI as if they do not know it behaved in this way there is no way of them addressing the issue.