Help figuring out why i crashed

[kingphoenix]

Ive had my phantom for just over a year made lots of flights, today wasnt a good day.

First my battery ran down from 100-5 in about 3 mins, lucky i noticed it just in time and was able to get it down @ 4%. Never had that happen before, i have 4 batteries that i cycle through.

Next im flying and the drone, and i see it spin on the screen then static look up to see it falling out of the sky. Luckily it was above an open field but it fell a good 50m-70m and got pretty messed up, it going to need some serious repairs, probably just get a replacement.

My main concern is diagnosing what happened, I usually shoot real estate videos so i definitely don't want this happening again, fall onto a house.

The battery is a little puffy, im going to toss it, didnt notice it before the flight but i dont remember if i would have noticed. (just doing some research and this battery is the only one I own that doesnt say v2.0 on it and im seeing reports of swelling on the v1)

Are there any logs created that i can check or im just out of luck?

Im thinking battery because I lost signal to my screen before it hit the ground.

Im using a phantom 2 with a h4-3d gimbal, I bought it as a kit bundled with:

• 1 x 5.8 Ghz Tx Video Transmitter System
• 1 x 7" Super Bright LED Outdoor Monitor with built-in DUAL DIVERSITY RECEIVERS , Built-in Battery, and Battery Charger
• 2 x 5.8 Ghz Omni-directional receiver antennas
• 1 x 5.8 Ghz Omni-directional transmitter antenna
• 1 x GoPro to Video Transmitter Cable

Thanks for any help.

 

[Morgas Resnak]

Can you upload your flight logs for all of us?

 

[kingphoenix]

Can you upload your flight logs for all of us?

Excuse my ignorance but where would that log be written to?

 

[pomonabill220]

Almost looks like a prop spun off... the level flight, then BAM tumbling fall.
Did you have all the props on the motors when it landed (crashed)?

 

[kingphoenix]

Almost looks like a prop spun off... the level flight, then BAM tumbling fall.
Did you have all the props on the motors when it landed (crashed)?

No actually, one of them is missing and we couldnt find it anywhere, the threads were pretty caked with dirt so i was wondering about that too. ( happened 4 mins into flight, i would think it would have spun off before that) The sounds from the video (motor sounds seem to stop as soon as it starts falling) and the lost communication as it started falling before it landed had me looking elsewhere for an issue tho. I saw the first 2 seconds after it starting dropping then static.

 

[pomonabill220]

Yes, I noticed the big change in prop noise just before it started to tumble.... that is what lead me to think that maybe you lost a prop... sorry to see it happen!

 

[kingphoenix]

Yes, I noticed the big change in prop noise just before it started to tumble.... that is what lead me to think that maybe you lost a prop... sorry to see it happen!

Would they quit if one flew off? i thought they be going into overdrive crazy trying to level it out again.

 

[pomonabill220]

I don't really know.... I don't believe the P2 has any kind of black box recorder though, so there wouldn't be a way to see what the quad was doing if/when the prop came off.
Still, I would think the flight controller would be trying to "right" the craft and would be going nuts trying.
The video does look like a prop came off though... others here might have other ideas though.

 

[pomonabill220]

just played back your video, and noticed that it sounded like the motors spun down less than a second before the tumbling started. Also seems to be a "click" sound at the same time.
What were you doing with the remote's sticks? Could you have possibly done a CSC? (sticks down and together)... NEVER do this in the air!!!

 

[pomonabill220]

At 6 seconds in the video, there is something white in the sky.... hhmmm
Almost looks like a cloud though...

 

[kingphoenix]

I don't really know.... I don't believe the P2 has any kind of black box recorder though, so there wouldn't be a way to see what the quad was doing if/when the prop came off.
Still, I would think the flight controller would be trying to "right" the craft and would be going nuts trying.
The video does look like a prop came off though... others here might have other ideas though.

Cool thanks for the input, i have to shoot a 5 million dollar home in the next 2 weeks... i think were gonna hire that one out.

At 6 seconds in the video, there is something white in the sky.... hhmmm
Almost looks like a cloud though...

Was flying forward as you can see in the video definetly didnt do a "CSC"

holy good eye, that looks alot like a prop actually

 

[pomonabill220]

did a frame by frame and you did loose a prop...

 

[pomonabill220]

Ya beat me to it!!!! Yep a prop!

 

[kingphoenix]

Ya beat me to it!!!! Yep a prop!

You're awesome thanks for the help, so glad it wasn't my fault somehow!(confidence restored) Now to figure out why that happened! Also helps explain why we could not find that prop anywhere.

 

[pomonabill220]

You are more than welcome!
All I can think of is that you didn't tighten the prop enough??? I know the P2 doesn't have active breaking, but the motor speeds still change and can spin the prop off if not tight enough.
What you experienced and recorded is a classic symptom of prop loss... the abrupt rolling from a smooth flight.
Still sorry to see the crash! A phantom pilot never wants to experience this.
Yeah... who knows where the prop ended up, and it's so small that it might never be found... but who knows?!?!?
....well I guess it DOES have active BREAKING.... just not active braking! lol

 

[kingphoenix]

You are more than welcome!
All I can think of is that you didn't tighten the prop enough??? I know the P2 doesn't have active breaking, but the motor speeds still change and can spin the prop off if not tight enough.
What you experienced and recorded is a classic symptom of prop loss... the abrupt rolling from a smooth flight.
Still sorry to see the crash! A phantom pilot never wants to experience this.
Yeah... who knows where the prop ended up, and it's so small that it might never be found... but who knows?!?!?

Well im pretty sure the props are self tightening so it doesnt really matter how tight you put them on, from what ive been reading it looks like an abrupt stopping of the motor could cause the prop to spin itself off.

 

[pomonabill220]

Well the self tightening claim is somewhat misleading. You still need to snug them on somewhat because of the ability of the motors to change speed abruptly while the props are still spinning, causing them to unscrew.
You would think that after being in the air "pumping" the air for a while, they would tighten up, but in reality they really don't tighten up that much and are still "unscrewable" and can come off.
Also, since they are biting into the air, trying to create downward force, ANY looseing will spin them off from a motor slowdown.

 

[kingphoenix]

Well the self tightening claim is somewhat misleading. You still need to snug them on somewhat because of the ability of the motors to change speed abruptly while the props are still spinning, causing them to unscrew.
You would think that after being in the air "pumping" the air for a while, they would tighten up, but in reality they really don't tighten up that much and are still "unscrewable" and can come off.
Also, since they are biting into the air, trying to create downward force, ANY looseing will spin them off from a motor slowdown.

Hmm well thats not good, my assistant put the props on so im not sure how tight he snugged them, i woudl think the initial start up would be enough to tighten them, i did a fair bit of flying and landed it and take off again (memory card error)

Oh well well see whats salvageable.

 

[Pharm]

Well im pretty sure the props are self tightening so it doesnt really matter how tight you put them on, from what ive been reading it looks like an abrupt stopping of the motor could cause the prop to spin itself off.

Self-tightening props are over-rated. You STILL need to tighten them. Interesting theory on the engine stop causing the prop to come off. It DOES sound like the motor(s) quit about the time of the fall. Can't tell unless I visually compare the audio waveform to the video, which I'll forget to do when I get home. That's definitely one possibility.

 

[pomonabill220]

That would be the next best thing to a flight log! Great idea!