Phantom 4 Pro RTK fell out of sky

This incident occurred on Tuesday, October 25th around 10:35AM-10:50AM

Our company drone a Phantom 4 Pro RTK, used heavily for surveying and autonomous flights for waypoints and 2D image taking, as well as video work.

I had arrived at my second job site, which was a recycling landfill. I station my vehicle off to a grassy part of the landfill, away from people and property.

I set the RTK mobile station and link the aircraft and remote to the mobile station with success, the week was planned for a week of the same procedures across numerous plants.

I set my waypoints and begin the flight, I installed the propellers and did my usual locking of the rotors with the propellers. Mind you, I am new to this position and the aircraft was used heavily before I arrived, dusty looking propellers and aircraft.

The drone takes off within a couple of seconds I hear a strange sound from the aircraft above, which I had no more eyesight of 200ft above ground. The drone comes spiraling fast until it crashed about 40-50ft where we it took off. Upon inspection the aircraft had 3 propellers on, one broken in half and the 4th propellers was about 80ft away from the aircraft in a bush. I contact my manager and informed him what happened so we could look at the .dat file in the office. showed an ESC error. Why I’m no expert in these things, and my first reported crash. This has caused tremendous amounts of stress as a new employee for this company. I would appreciate someone knowledgeable in this area to please look at my .txt file (linked below) to explain in an easy way to understand what happened. I will present my findings to the board of directors of this incident and would like to be prepared- I am already seeing numerous accounts of the same crash reports due to what showed.

If there is anything I can do to provide please let me know. Thank you so much!

Can you attach the correct TXT flight log or share your Airdata link?


That’s what I’m seeing in your flight log too. It looks like that prop disconnected from the aircraft at about 228 feet after 17 seconds into the flight.


What could have been the cause?

Some common causes:

  • Prop was not installed properly
  • Prop was damaged prior to takeoff
  • Prop struck an object mid flight (less common)

I’m sure all propellers were installed correctly.
Is it remotely possible for the bird to ascend 228ft? With a propeller not placed on correctly? Also, would airdata show a “propeller fell off” message in the log report? Which did not.

Then you might have been flying with a damaged prop. It’s quite possible for there to have been small cracks around the prop hub – hidden by the heavy use and dust from previous flights.

Definitely not. If you play your flight log back, you’ll see it doesn’t start to spin in circles until it reaches about 228 feet. That spinning is what normally occurs when all props are not attached.

Another possibility would be a bad ESC/motor. However, that doesn’t seem to be the case since the entire prop was not attached to the drone when you retrieved it. Also, motor and ESC failures aren’t as common. I cannot say I’ve ever heard of a crash where the drone hit the ground, a prop completely spun off, and was ejected 80 feet away.

I have seen an error like that, but the “Not Enough Force” error is more common in this case. The drone doesn’t know if the props are attached, so it would be tough to know when to show the “missing prop” error instead of the “Not Enough Force” error.

I appreciate your time and detailed response to this situation.

I think we both agree on the ascending of 228ft the bird with only one prop not installed correctly, it is not possible.

The ESC error occurred when the prop fell off and tried to compensate?

Yeah, I think it’s more likely that the prop was damaged or became damaged mid flight.

That error was the result of the issue that occurred at that point in the flight. Like we’ve been discussing above, the actual issue might have nothing to do with the ESC.

Thank you once again,

Im just left confused with your initial statement of the propeller not placed on correctly, then we both agreed that a drone is not physically able to ascend that high with just 3 propellers placed on correctly and one not.

I inspected the whole propeller that fell off and I noticed tad bits of plastic inside the propeller, like scratches- the other propellers did not have those signs.

To clarify, I was only agreeing that it would be impossible for a DJI drone to ascend to such an altitude with only 3 props attached.

Oh okay, so it can ascend with the 4th not placed on correctly?

Any kind of installation that allows a prop to remain attached to the motor would allow the aircraft to ascend.

For the P4P specifically, it would probably be pretty tough to install the prop incorrectly and have it remain attached. However, it would be easy to install a damaged prop or fly with a damaged prop lock.

I agree,

Some have stated the prop will self lock with the P4P.

Let’s put the theory that propeller was placed incorrectly (which was not in this case). The bird will ascend but wouldn’t it have fallen at a lower altitude? In fact I’ve tried the theory myself, on my own personal P4P. The bird tips over immediately upon the rotors starting.

Right – this probably was not the cause in your case.

Thanks! You helped a lot.
Just for reference are you an official DJI representative or moderator?

I will present my findings to my managers and composing enough data to be ready.

While I do work with DJI, I’m not an employee or representative. You can contact DJI support directly if you’d like them to comment on your flight.

I would like that, where would I reach them at?