Mavic flies very slow at 100% pitch, then speeds up suddenly and crashes into tree

[ontheroadmedia]

Hi forum!

The other day, I flew (and crashed) my Mavic. It showed some strange behaviour before the crash and I would like to understand, what happened.

Here's the DAT file of the flight: Dropbox - FLY159.DAT

And the CSV file: Dropbox - ExportCSV_2017-08-29_[07-56-42].csv

1. Reaching a height of 30m/ 100ft (at 00:17sec flight time), the controller showed a warning message saying that I had reached max. flight altitud. My max. flight altitud was set to 200m though. I tried to get higher (at 00:24, 00:38, 00:41, 1:11), but the drone wouldn't let me.

I decided to continue with the flight, as I needed some shots. Other from the up-pitch, the drone responded well, until...

2. At 50m flight distance (3:06 flight time), the controller showed a message that I had reached max. flight distance. My max. flight distance wasn't restricted to 50m/ 160ft in the settings.

3. Despite the warning, I was then able to go further than 50m/ 160ft, performing a shot at low speed.

4. This was were the drone started moving very slowly. I had the stick pitched to 50-75% forward and then backwards, but the drone would only fly at around 2.5-4mk/h (from 3:50 to 4:34). Starting at 4:45 flight time, I pitched the stick 100% forward, but the drone would only fly at a max. of 5m/h.

3. To fly back to landing position, I moved the stick both forward and sidewards at 100% (4:53) and the drone would still not speed up. At 4:56 flight time if release the forward stick and the drone suddenly speeded up. I was surprised, tried to brake but had to see my Mavic crash into a tree.

My question is: Why did the Mavic fly so slow in forward and backward mode?

I exchanged some Emails with Mike Singer of MavicHelp, who was very patient and helpful. He asked me to tag @BudWalker here, who might have some more insights.

Your help is much appreciated as I hope warranty might pay for the repair.

Best,
David

 

[SYC12]

Did you set or default MP to "beginner mode"?

 

[ontheroadmedia]

No, it wasn't set to beginner mode.

 

[BudWalker]

Hi forum!

The other day, I flew (and crashed) my Mavic. It showed some strange behaviour before the crash and I would like to understand, what happened.

Here's the DAT file of the flight: Dropbox - FLY159.DAT

And the CSV file: Dropbox - ExportCSV_2017-08-29_[07-56-42].csv

1. Reaching a height of 30m/ 100ft (at 00:17sec flight time), the controller showed a warning message saying that I had reached max. flight altitud. My max. flight altitud was set to 200m though. I tried to get higher (at 00:24, 00:38, 00:41, 1:11), but the drone wouldn't let me.

I decided to continue with the flight, as I needed some shots. Other from the up-pitch, the drone responded well, until...

2. At 50m flight distance (3:06 flight time), the controller showed a message that I had reached max. flight distance. My max. flight distance wasn't restricted to 50m/ 160ft in the settings.

3. Despite the warning, I was then able to go further than 50m/ 160ft, performing a shot at low speed.

4. This was were the drone started moving very slowly. I had the stick pitched to 50-75% forward and then backwards, but the drone would only fly at around 2.5-4mk/h (from 3:50 to 4:34). Starting at 4:45 flight time, I pitched the stick 100% forward, but the drone would only fly at a max. of 5m/h.

3. To fly back to landing position, I moved the stick both forward and sidewards at 100% (4:53) and the drone would still not speed up. At 4:56 flight time if release the forward stick and the drone suddenly speeded up. I was surprised, tried to brake but had to see my Mavic crash into a tree.

My question is: Why did the Mavic fly so slow in forward and backward mode?

I exchanged some Emails with Mike Singer of MavicHelp, who was very patient and helpful. He asked me to tag @BudWalker here, who might have some more insights.

Your help is much appreciated as I hope warranty might pay for the repair.

Best,
David

Reading the description I realized this sounds vaguely familiar. I had the same kind of restrictiond happen to me once. I don't remember exactly. I was going to ask about the beginner mode. It may have been a situation where I hadn't accepted the GeoFence stuff. Something like that. Sorry, I'm an old guy.

I did look at the .DAT and it's pretty much as described. One thing I noticed is that increase in speed was coincident with negative throttle dropping the Mavic below 26.8 meters. I'm thinking that the higher speed was allowed once the height and distance constraints were both satisfied. But, you'd expect the constraint satisfaction to occur when the height < 30 meters not 26.8 meters. Maybe there is some buffer on the downside to make sure that the height restriction is met.

 

[ontheroadmedia]

Thanks a lot, @BudWalker!

Do you see any chance, that DJI might classify this as a warranty case and respond for the repair? I am asking, because I am living in Mexico, but since I bought the drone in the US, I would have to send it to US for them to check it. If there's no chance DJI will respond, I would repair it here in Mexico.

Thanks again!

 

[BudWalker]

Thanks a lot, @BudWalker!

Do you see any chance, that DJI might classify this as a warranty case and respond for the repair? I am asking, because I am living in Mexico, but since I bought the drone in the US, I would have to send it to US for them to check it. If there's no chance DJI will respond, I would repair it here in Mexico.

Thanks again!

Well, DJI won't ask me but, I'd think not. After all, you flew past the warnings that were issued.

OTOH, my analysis could be total nonsense and the incident was caused by something else that wasn't your fault.

Good Luck.

 

[ontheroadmedia]

Thanks!