GET OUT OF JAIL FREE - WARRANTY CLAUSE - FAKE ANALYSIS

[With The Birds]

Why DJI chose to program RTH flight slower than regular flying is one of the unsolved mysteries of dronedom.
I've never heard a satisfactory explanation.

Unfortunately the flight data stops just after the Phantom has begun to make headway towards the home point.
Despite only flying at 11 mph, it took 8.5 secs and 107 feet to come to a stop.
The Phantom begins to accelerate but the data stops 2.3 seconds later.
We can't really tell the strength of the wind because we don't know what speed it might have attained but can compare this acceleration with what the Phantom did at the start of the flight
RTH acceleration 0-2.7 mph in 2.3 secs
Start of flight - 0-11mph in 2.3 secs

Thanks Meta- I would like to think, in a lost signal scenario, that a 22MPH headwind (or even worse higher) would not prevent the AC returning. That is the AC would attempt to fly against the prevailing wind to maintain ground speed rather than being limited to an airspeed of 22mph) as you and many others (myself included on earlier occasions) have suggested.

 

[microlinux]

Sorry, I beg to differ. Flying high and at a reasonable distance is not an issue if you have prepared for the flight and are comfortable with your settings and your ability. Checking the wind can be done by either using one of the many wind predicting apps out there or simply taking the quad up, switch to atti mode and observe any drifting and fly accordingly. I suspect that this may not have been the case in the OPs instance and having a crack at DJI is probably not the solution. It is impossible for me to keep VLOS as my take off point is at the base of 30 mtr trees, but I am confident through experience and being conservative and have never had an issue that wasn't through my own act or omission. I don't intend to crash my investment, much the same as I don't intend to bin my superbike at the racetrack. Same methodical approach to preparing for both my hobbies applies.

I actually agree. Like I said, there's nothing wrong with pushing the limits (hell, that's half the fun of anything!) - you just have to be prepared and accept the risk. This seems like a good example of that. I wasn't there - but the conditions of the flight seem dubious.

 

[V tail]

Why DJI chose to program RTH flight slower than regular flying is one of the unsolved mysteries of dronedom.
I've never heard a satisfactory explanation.

My thought on this was, as a G/A pilot, was akin to best glide speed.

Some DJI mathematicians may have come up with 22mph as the best speed to cover the most distance (not factoring for wind obviously).

I have, of course, zero to back this up. Just a theory.

 

[Meta4]

My thought on this was, as a G/A pilot, was akin to best glide speed.
Some DJI mathematicians may have come up with 22mph as the best speed to cover the most distance (not factoring for wind obviously).

This is a common suggestion but flying so slowly is not going to give the best distance.
You achieve max distance by flying just a tad less than full speed.
Best fuel efficiency tests

 

[DanMan32]

Apparently DJI believes high current draw on low battery could damage the battery as I got a notification on my P3 that output was reduced to protect the battery when it was heading home on low battery.
And I was expecting RTH on signal loss at the time too.

 

[Magicmanp4]

Wind at that height is the
key into the investigation, upload your original data to healthy drones and get your wind speed from there, love to see the data, example attached

 

[Magicmanp4]

 

[tevek]

I actually agree. Like I said, there's nothing wrong with pushing the limits (hell, that's half the fun of anything!) - you just have to be prepared and accept the risk. This seems like a good example of that. I wasn't there - but the conditions of the flight seem dubious.

Agreed sir!

 

[sumnerwolf]

Here are some things I noticed from your flight log:

• You took off with a battery that was only 68% charged
  
• You waited to initiate RTH until the battery was 59% charged at ~3.6V (it's best to be on the ground at 3.3V)
• Your Phantom was 4,535 feet from the home point when RTH was initiated
• It's apparent that the wind was very strong since your Phantom was only traveling at 2 MPH near the end of the flight log

A lot of pilot mistakes were made here. I don't know if it's fair to blame DJI on this one.

Thanks for the reply. In your post you put that it's beat to be on the ground at 3.3 which would put it on 50% charge. Also that it was returning at 2 miles per hour. The point is it that it was returning home so why disconnect from the controller when it was getting closer. And then not re connect?? Also ad I only gave one battery because that was what came with it..... I had already been up that day only half an hour before.

 

[rene van der meer]

Thanks for the reply. In your post you put that it's beat to be on the ground at 3.3 which would put it on 50% charge. Also that it was returning at 2 miles per hour. The point is it that it was returning home so why disconnect from the controller when it was getting closer. And then not re connect?? Also ad I only gave one battery because that was what came with it..... I had already been up that day only half an hour before.

Did you recharge it to 100%?

 

[msinger]

In your post you put that it's beat to be on the ground at 3.3 which would put it on 50% charge.

The percentage is not important. When the first battery cell reaches 3.0V, the battery will auto shut off (see more details here). Before that occurs, the battery will reach the critically low level and the Phantom will start auto landing at its current location. In most cases, it does make it to the ground in time. The key is to land before the battery reaches the critically low level.

I only gave one battery because that was what came with it..... I had already been up that day only half an hour before.

It's never a great idea to set off on a long distance flight on a nearly depleted battery -- even if you only own one battery.

 

[V tail]

You achieve max distance by flying just a tad less than full speed.
Best fuel efficiency tests

DJI should hire the guys in this thread doing the math.

 

[AlecW]

The point is it that it was returning home so why disconnect from the controller when it was getting closer. And then not re connect?? Also ad I only gave one battery because that was what came with it..... I had already been up that day only half an hour before.

It's somewhat irrelevant that it disconnected during RTH since you flew it so far out and so high in such a strong wind with a depleted battery, all the wrong things to do, all covered in the manual, it simply wasn't gonna make it home.

Why the "I lost my drone story" bashing and cussing DJI without understanding the logs or asking for advice on how to read them? Are you trying to hurt DJI because or your mistakes? The internet is gradually changing and these types of posts are no longer hurting companies, people are smart and realize it's just someone is venting.

 

[sumnerwolf]

It's somewhat irrelevant that it disconnected during RTH since you flew it so far out and so high in such a strong wind with a depleted battery, all the wrong things to do, all covered in the manual, it simply wasn't gonna make it home.

Why the "I lost my drone story" bashing and cussing DJI without understanding the logs or asking for advice on how to read them? Are you trying to hurt DJI because or your mistakes? The internet is gradually changing and these types of posts are no longer hurting companies, people are smart and realize it's just someone is venting.

There where many factors in the loss of the drone. The big one was the disconnection from the controller and then not re connecting. Also there was a fault with the obstacle sensor. For all I know it could have hit something which is why it disconnected and was never seen again. That right there would be a fault under the warranty. A battery of 68 percent is no a risky business to fly. It disconnected with 58 percent. ...... did not re connect. Last known it was returning slowly. I ran towards it to get closer but still didn't reconnect. Was at last known location.

There was a fault with connection to controller otherwise it would have reconnected and told me where it was.

 

[sumnerwolf]

This is the results sent to me about the analysis. Now tell me you wouldn't be frustrated?


Thanks for your patience.


For your claimed case CAS-477928-K4C7L3, we have already finished the analysis, and the result is as follows:


1. The aircraft was piloted under P-GPS mode;

2. T=02-18, h=107m, d=1296.2m, aircraft inclined pitch (-5.0) roll (25.4) without stick commands and flew at a speed of 1.6m/s horizontally;

3. T=03-11, h=205m, d=1374.6m, aircraft inclined pitch (-15.8) roll (19.5) without stick commands and flew at a speed of 4.5m/s horizontally;

4. T=03-24, h=206m, d=1415.5m, flight record ended and aircraft was blown away;



According to the analysis, the incident was not caused by any product malfunction factors. As such, we could not provide warranty service.


Should you have more questions, please feel free to let me know.


Best Regards,



Sophia

DJI Tech Support

DJI - The Future Of Possible

 

[sumnerwolf]

So no stick movement from one to the next result blown away. Where is anything about what happened the faults that occurred. The disconnection. The sensor error. The slowing down Turing and moving towards me

 

[sumnerwolf]

As I said get out of jail free warranty clause

 

[AlecW]

For all I know it could have hit something which is why it disconnected and was never seen again. That right there would be a fault under the warranty.

Ask yourself what it would have hit at the height you were at. A bird perhaps?

 

[sumnerwolf]

Actually it was at the side of a really big hill I was out walking near settle in Yorkshire. Not really big enough to call mountains. But you get the gist

 

[tcope]

The analysis showed that from one point to another with no movement of the controller that it was moving and as such it was blown away - do not fly in strong winds is in the warranty, but what constitutes strong wind?? there was nearly no wind when i set it off, it hit some wind whilst in the air but nothing that it was not able to
cope with.