Drone flips when backing off throttle

[PrhapsiSuppose]

Hi all,
i have a few builds and this one is my 250 which I use main mainly for filming (because I can't afford a phantom yet)
If I am hovering around, it flies perfectly fine, I can accelerate and it flies fine, but if I pin it and then back off the throttle, it just falls and flips uncontrollably into the ground, nearly impossible to recover.
When I first built it, there was a short, which released magic smoke from the motors, I since fixed the short and everything SEEMS to be fine, except this issue. Thing I fried the FC or something?
Flying in Rattitude.
Any ideas?

20A little Bees
2205 2300kv Race Stars
Matek PDB
CC3D tuned with openpilot

Let me know if you need additional info.

 

[Wildwelder]

That might be an accelerometer issue. Probably needs calibtaring. My 280 does that too if I nail it. Thats alot of work for the fc to do in a very short amount of time esp if it isnt calibrated perfectly. I just learned to roll on the throttle.

 

[PrhapsiSuppose]

I noticed, if I give it throttle and then cut throttle, the front two motors stop spinning almost immediately. The rear two motors spin for about 1-2 seconds as they slowly lose momentum and then stop. This could certainly cause the flip i would think. What would cause the rear two motors to spin longer? how can I make it so they all stop at the same time?

Thanks!

 

[Wildwelder]

Have you gone into openpilot/librepilot and calibrated anything? You can test the motors there. You may have smoked the escs with the short. Are any of the wires going to the fc damaged?(speaking from experience on that one). Only takes a split second to render the esc useless

 

[PrhapsiSuppose]

Have you gone into openpilot/librepilot and calibrated anything? You can test the motors there. You may have smoked the escs with the short. Are any of the wires going to the fc damaged?(speaking from experience on that one). Only takes a split second to render the esc useless

I just replaced the ESC's on the problematic motors, and it's Looking like that might have been the issue! All motors now stop spinning at the same time. Will have to test flight, but that has to be what the problem was.

I guess since it did still "fly".. (just not well) that the ESC's were fine. Goes to show! all it takes is a split second to fry an ESC.

Thanks Everyone!
Glad to be a part of such a great community.