New guy here. Afraid I messed up my first phantom! 1 slow prop.

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Hello! I have learned a great deal from these forums and am excited about my first drone (Phantom 3 pro). I was hoping my first post would be some cool videos but I had a crash and now I am worried I screwed something up. Long story short I was calibrating the gimbal on my basement floor and took off, lost it somehow and it drifted into a wall rear props first and got tangled and fell to the ground. I shut it off asap but the rear props were being prevented from spinning while they were against the wall.

I noticed one prop now spins slightly slower at idle. Or at least I noticed it after the crash. Flight is still perfect. The slower spinning is only at idle speed from what i can tell. No jello in the video at all and it stays perfectly level and it doesnt seem to be corrected itself at all. Below are two videos. The first one is idle speed sitting on the ground. Slo mo video. The first slow mo video GREATLY exaggerates the difference in speed, but it proves it exists. It is barely noticeable in real time. The second video is in a hover from above. Shows no difference in speed that i can tell other than idle.

My question is do you think I should be concerned about this? When I manually turn the motor it feels no different than the other 3 at all. Only at idle i can tell it is just slightly slower. Im just bummed out because I dont want to worry about this thing just dropping out of the air. I use it almost exclusively over salt water.

Thanks so much for any input!

Idle speed (iphone slow mo):
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Hovering:
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When power is still on and a prop gets stopped or lodged the ESC tries to throw more power to that motor. If the motor is not turning then the ESC heat up and can be damaged. It's to much money to take a chance with. If it was me I would change out the ESC and see if it corrects the speed problem. You need for all props to be the same at idle and at full speed. Better to be safe than sorry.
 
try recalibrating the imu....it's possible when its idling it may think it's on an angle and thus slowing the prop on that side.
 
try recalibrating the imu....it's possible when its idling it may think it's on an angle and thus slowing the prop on that side.

So I did the IMU calibration. Now when I first turn the rotors on they seem to be going at at the same speed again. BUT now about 15 seconds after you turn the props on while its idleing the motors will speed up a little bit by themselves and it will shake a little bit. Any ideas? Seems like a software thing at this point though.
 
So I did the IMU calibration. Now when I first turn the rotors on they seem to be going at at the same speed again. BUT now about 15 seconds after you turn the props on while its idleing the motors will speed up a little bit by themselves and it will shake a little bit. Any ideas? Seems like a software thing at this point though.
That's normal on start up, the rpm will burst up very briefly and then go back to normal idle. At least that is what it does on mine. Haven't heard a lot of conversation on the forum from other members stating that this was an issue, so I just assume it happens as a normal course of power up. If it goes up and doesn't go down-- instantly, then yes-- it is an issue that would be very bad. If it is an issue, someone else will chime in here.
 
So I did the IMU calibration. Now when I first turn the rotors on they seem to be going at at the same speed again. BUT now about 15 seconds after you turn the props on while its idleing the motors will speed up a little bit by themselves and it will shake a little bit. Any ideas? Seems like a software thing at this point though.
Not sure....maybe a bad motor bearing ? Not really sure...can you make a small video showing the issue?
 
Not sure....maybe a bad motor bearing ? Not really sure...can you make a small video showing the issue?

They seem to be spinning at the same speed now at idle after the IMU calibration, but for some reason after i start the motors they will speed up a little after idleing for about 15 seconds. This is after the initial 2 normal bursts it does right after turning the motors on. It idles normally then speeds up a little bit causing it to shake after about 15 seconds. It flies fine. Ill try to post a video when i can.
 
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They seem to be spinning at the same speed now at idle after the IMU calibration, but for some reason after i start the motors they will speed up a little after idleing for about 15 seconds. This is after the initial 2 normal bursts it does right after turning the motors on. It idles normally then speeds up a little bit causing it to shake after about 15 seconds. It flies fine. Ill try to post a video when i can.
cool.....and have you ruled out the props being broken or bent? have you tried with the spare set?
 
cool.....and have you ruled out the props being broken or bent? have you tried with the spare set?

Props are fine. I tried changing them all. The issue now is when i turn the motors on by pushing each stick down and toward each other, the phantom thinks it is in the air. It doesnt just sit there and idle like it used to. So when i start the rotors before take off with the controller sticks i dont have the option for auto takeoff. Just the option to auto land in the app even though I never took off. I think its just completely screwed up at this point. The IMU calibration basically took away the phantoms ability to be turned on at an idle.
 
Props are fine. I tried changing them all. The issue now is when i turn the motors on by pushing each stick down and toward each other, the phantom thinks it is in the air. It doesnt just sit there and idle like it used to. So when i start the rotors before take off with the controller sticks i dont have the option for auto takeoff. Just the option to auto land in the app even though I never took off. I think its just completely screwed up at this point. The IMU calibration basically took away the phantoms ability to be turned on at an idle.

Calibrate the TX in the RC assistant and Phantom assistant.
 
Props are fine. I tried changing them all. The issue now is when i turn the motors on by pushing each stick down and toward each other, the phantom thinks it is in the air. It doesnt just sit there and idle like it used to. So when i start the rotors before take off with the controller sticks i dont have the option for auto takeoff. Just the option to auto land in the app even though I never took off. I think its just completely screwed up at this point. The IMU calibration basically took away the phantoms ability to be turned on at an idle.
Have you checked the MOD values? Are they all in the range they should be? Maybe try toggling VPS on/off to see if that has an effect. These are just ideas though to test what may be wrong....if you have insurance you may just want to enact that option....otherwise I'd be happy to keep blurting out ideas :)
 
So when i start the rotors before take off with the controller sticks i dont have the option for auto takeoff. Just the option to auto land in the app even though I never took off.

You should never have the auto take off option after the motors are started. You should only see that if the motors are off. Basically there are two options: start the motors with the CSC and take off manually, or use the auto-take off to start the motors and immediately take off.

It sounds to me like the IMU calibration fixed your problem. I'd fly her in an open field and test things out keeping her relatively close to you.

I hope it's ok but sounds like it is.
Chris
 
Thanks you guys for your ideas and help. Basically, I think the IMU calibration may have fixed the rotor speed issue. But I am increasingly suspect that there may not have been one in the first place. I was assuming there was a specific set "idle" speed but from the sound of it the idle speed is not a set in stone RPM?

I did some test flights and the props seem to be spinning at similar speeds now, but it's hard to tell because it doesn't "idle" like it did pre-IMU calibration. I did do an RC calibration a few minutes ago as suggested but have not had time yet to see how that effects things.

Bottom line is I did some test flights and the thing stays perfectly level aside from wind blowing it. The video shows no sign of jelloness. I got to the point where I was comfortable going full speed about 10 feet over the water and the recorded video is perfectly smooth and the drone flew in a straight line. If there is anything wrong with the drone at this point, it's not effecting performance in the air.

Thanks again for your responses. I am looking forward to using the phantom a lot more!
 
I have not had this issue with the P3 but did twice with P2V+.
I went ahead and replace the ESC and motor both times but i believe at least once it was just the motor. It would idle slower but the flight was fine. I did, however, notice that motor would hear up quicker and I was able to faintly smell the burnt electric motor smell.

At least for the P2 the motor and ESC were around $25 each so a relatively small price for peace of mind.
I was nervous to soldier on the bird but it wasn't bad at all. Just be patient.
Good luck. Please let us know what you find out.
 
When power is still on and a prop gets stopped or lodged the ESC tries to throw more power to that motor. If the motor is not turning then the ESC heat up and can be damaged. It's to much money to take a chance with. If it was me I would change out the ESC and see if it corrects the speed problem. You need for all props to be the same at idle and at full speed. Better to be safe than sorry.
On P3 the escapements are part of the main board, not replaceable separately. On another post I read that on the P3 they shut off if the prop is jammed and draws too much power and after a reset they will still work.
 
On P3 the escapements are part of the main board, not replaceable separately. On another post I read that on the P3 they shut off if the prop is jammed and draws too much power and after a reset they will still work.

I read this too. The drone seems fine. The props didnt even require a reset and the one that appeared to be spinning slower after the crash seems normal now after an IMU reset.
 
I would suggest you not put the props on indoors until you learn all there is to know about P3 and have a lot of flight time.
 
I found this video about the IMU calibration. It's a must watch and spot on with its information. He's a bit repetitive but has great advice on the right way to do an IMU calibration. Especially if your noticing long warm up times on start up. Cut my warm up times in half!
Might help here too.

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I found this video about the IMU calibration. It's a must watch and spot on with its information. He's a bit repetitive but has great advice on the right way to do an IMU calibration. Especially if your noticing long warm up times on start up. Cut my warm up times in half!
Might help here too.

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Great vid. Gonna follow this as i want to do another calibration after the new firmware update.
 

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