Unexpected p3 takeoff

[Itay]

I've seen this before. If you would have auto-taken off, I think it would have actually started the engines and pulled it up immediately. Because you tried to just arm the motors, it spins the motors quickly and then the RPMs come back down. I've seen someone else's flip exactly like that because they too were on the smallest of unlevel surface when trying to arm.

I think you are right. I did a small test now. I removed the props and places the phantom in a similar angle. Not so steep, and armed the engines. Guess what. Two of the engines spinned faster, so using my hand I gently tilted it a bit more so the angle was a bit steeper, and the engines started spinning very fast. Exactly what happen to me yesterday!!!
Conclusion...never start the phantom when it's tilted because even when you just arm the engines, it its tilted the flight controller will mistake and spin 2 of the engines fast.

 

[Itay]

This is how my props look now. Can I still use them or get new ones?

 

[JohnK]

This is how my props look now. Can I still use them or get new ones?

View attachment 29716

Do you have a prop balancer? They don't have to look pretty to function properly, but vibrations can take a cumulative toll over time.

 

[Fplvert]

Balance is important, but even small chips can induce vibration. Error on the side of caution if they have any visible damage. Use your spares and order some new ones.