Why did this hsppen??

[Kissthesky]

Was the battery in the aircraft after the crash?

No...I figured it popped out from hitting the ground

 

[Kissthesky]

From what I can tell from the flight logs it lost power had about a 127 feet. If that is true...it came down hard! Probably what broke the arms AND the camera

 

[PhantomWetSuits]

Since the flight logs do not show much, the key has to be the loud gear grinding noise can you elaborate on that, as that could have been the battery coming loose causing the props to whine down or what you might be calling grinding noise. ?

 

[Kissthesky]

From the pic you can see that one blade is snapped and the other is bent. It sounded like props hitting the body...a series of tap, tap, tap...really fast

 

[Kissthesky]

No whining down..wrong noise

 

[Kissthesky]

If you can imagine what it sounds like when a plastic gear grinds...that's what it was...then it dropped

 

[sar104]

If you can imagine what it sounds like when a plastic gear grinds...that's what it was...then it dropped

The sudden voltage drop and resulting crash was clearly caused by loss of battery power, for undetermined reason. But I cannot see any way that would be related to the noise that you heard or any kind of prop failure.

 

[BudWalker]

@Kissthesky is there any evidence that the battery was hit by the rightBack prop? The reason I'm asking is that 140 millisecs before the voltage drop (618.612 secs) the Z axis gyro and Yaw look like what could be expected if one of the props was hitting something.

I'm supposing it might be the rightBack because that motor shows increased current

And, I believe you when you say the battery was secure when the flight started. Isn't it possible there is a defect that allows it to come loose?

 

[Kissthesky]

Im not sure what it could have possibly hit as it was way above anything. If a bird hit it i could see that. Yes, the battery is of utmost importance to me before I EVER take off!! I never fail to properly secure it. It is at the very top of my checklist!!

 

[BudWalker]

Im not sure what it could have possibly hit as it was way above anything. If a bird hit it i could see that. Yes, the battery is of utmost importance to me before I EVER take off!! I never fail to properly secure it. It is at the very top of my checklist!!

Sorry, maybe I didn't state my question clearly. Is there any evidence that a prop hit the battery? Are there scuff marks on the battery that look like it was hit by a prop?

 

[Kissthesky]

Downloading the DAT37.ill have it to you shortly

 

[Kissthesky]

DAT37

 

[Kissthesky]

I'll check

 

[Kissthesky]

There are scuff marks...possibly from the blade or possibly from hitting the ground...cant be sure

 

[Kissthesky]

@Kissthesky is there any evidence that the battery was hit by the rightBack prop? The reason I'm asking is that 140 millisecs before the voltage drop (618.612 secs) the Z axis gyro and Yaw look like what could be expected if one of the props was hitting something.
View attachment 98956
View attachment 98957

I'm supposing it might be the rightBack because that motor shows increased current
View attachment 98958

And, I believe you when you say the battery was secure when the flight started. Isn't it possible there is a defect that allows it to come loose?

Very possible yes

 

[BudWalker]

DAT37

This .DAT (FLY037.DAT) is from the next day. It's 27 minutes without the motors ever being started. Anyway, it's not a continuation of the incident flight FLY036.DAT.

I believe you when you say the battery was secure at the start of the flight. I suspect there must be some defect that allows secure batteries to come loose. But, my opinion probably won't do you much good. IMHO the data and your report of the grinding noise all seem to be consistent with a battery that came loose.

 

[Kissthesky]

So they probably are not going to warranty the drone I'm assuming. I need to turn it into my insurance?

 

[BudWalker]

So they probably are not going to warranty the drone I'm assuming. I need to turn it into my insurance?

Check out what's happening here
P4 Dropped like a brick midflight

 

[BudWalker]

So they probably are not going to warranty the drone I'm assuming. I need to turn it into my insurance?

and here
New P4P battery sensor prevents takeoff with dislodged battery

 

[sar104]

This .DAT (FLY037.DAT) is from the next day. It's 27 minutes without the motors ever being started. Anyway, it's not a continuation of the incident flight FLY036.DAT.

I believe you when you say the battery was secure at the start of the flight. I suspect there must be some defect that allows secure batteries to come loose. But, my opinion probably won't do you much good. IMHO the data and your report of the grinding noise all seem to be consistent with a battery that came loose.

Is the hypothesis that the battery slid out and contacted the rear props? The rate gyros and accelerometers all register the first sign of the anomaly at 618.61 and the voltage drop first registers at 618.76. But to hit the props the disconnect would have to have happened first, prior to 618.61, followed by a time interval for the battery to move far enough to hit the props, which leaves a rather long gap between disconnect and voltage collapse.

Or could a failed prop have hit the battery and caused the disconnect?