Drone spins and crashes, can anyone help?

[dozadog]

I have a DJI phantom FC40 I bought second-hand, it flew great at first. Bought a new gimbal for it, had a few more flights. Now it doesn't fly for long before spinning clockwise and crashing. I replaced a suspect motor, recalibrated. Still doesn't help, even when it is unladen it still crashes. Seems to wander a lot now too in GPS. I attach snap of the compass readings because that is the usual suggestion for wandering.

I want to fly it more but its making me lose all confidence in flying drones in general as its unsafe, I'm ready to give it all away. Is there any suggestion of tests I can do to diagnose the problem or a fix? if I fly in ATTI and it still crashes will it show its not the compass?

Any advice would be most appreciated.

 

[Deleted member 62848]

I have a DJI phantom FC40 I bought second-hand, it flew great at first. Bought a new gimbal for it, had a few more flights. Now it doesn't fly for long before spinning clockwise and crashing. I replaced a suspect motor, recalibrated. Still doesn't help, even when it is unladen it still crashes. Seems to wander a lot now too in GPS. I attach snap of the compass readings because that is the usual suggestion for wandering.

I want to fly it more but its making me lose all confidence in flying drones in general as its unsafe, I'm ready to give it all away. Is there any suggestion of tests I can do to diagnose the problem or a fix? if I fly in ATTI and it still crashes will it show its not the compass?

Any advice would be most appreciated.

Wow that suc,,,not own one but sounds like calibration all up the ,,,,,,,,,, what happens when you calibrate does it come normal or keep wanting to spin,,,props balanced even

 

[Yarome]

Have you tried flying in different areas.. and if so.. does it exhibit the same behaviour? It almost sounds like it's getting hit with interference. Possibly a ham operator in the area? New tower? It very well could be a bad board, but I would try and rule out the obvious first before you get too discouraged.

 

[Duchunter]

Dumb question but are the props in the right location? That will do it every time.

 

[Kagama]

I had my old phantom 2 spiralled clockwise and crashed once when I accidentally intersected a directional antenna for wireless internet that was mounted on a house.

It sounds like you might be hitting interference like I did.

 

[Scott Davis]

Have you tried flying in different areas.. and if so.. does it exhibit the same behaviour? It almost sounds like it's getting hit with interference. Possibly a ham operator in the area? New tower? It very well could be a bad board, but I would try and rule out the obvious first before you get too discouraged.

I don't believe it's likely a HAM operator. We don't operate in the same bands as Drones do. I tested my radios and flew my Phantom 4 close to my antennas while the wife keyed the radios. Nada. No interference.

It's not impossible, but I'd look elsewhere.
73's

Scott
N8JYF

 

[Yarome]

We don't operate in the same bands as Drones do.

I wasn't thinking so much about the frequencies.. more just about the EMF that "might" affect the compass. That's not really in my wheelhouse... just spitballing. If it's happening only in that particular area then there might be some outside influence/distruption at play.

 

[Kagama]

N8JYF[/QUOTE]

I don't believe it's likely a HAM operator. We don't operate in the same bands as Drones do. I tested my radios and flew my Phantom 4 close to my antennas while the wife keyed the radios. Nada. No interference.

It's not impossible, but I'd look elsewhere.
73's

Scott
N8JYF

That might have something to do with the signal being AM and having a quiet information wave on the carrier and a low power transmitter.

When I worked on jets I knew that the HF system could blow out truckers CB radios if we tuned to their channels and spoke into the microphone. These were powerful radios and I regularly did Operation checks in which I called a base in Alaska from Washington State.

 

[Kagama]

I wasn't thinking so much about the frequencies.. more just about the EMF that "might" affect the compass. That's not really in my wheelhouse... just spitballing. If it's happening only in that particular area then there might be some outside influence/distruption at play.

I'm pretty sure that a strong radio signal can throw off the compass and cause a crash since there is no real shielding inside the Phantoms and the compasses are pretty sensitive.

I'm really sure that they intersected a wireless antenna WiFi stream since they can operate on frequencies that the Phantoms work on and could easily overpower the commands from the remote.

I worked COMM/NAV in the Air Force so I have a decent grasp on things that can transmit.

 

[Fester]

Have you looked at the data for stick inputs? Be kind of curious there.

 

[dozadog]

Thanks for all suggests. I'm ready to bin it It does the same spin and crash wherever i am at any location.I thought it might be the 9450 props so im gona try the shallower angled ones. I'll try and post a video of it doing the spin crash. I'll check the stick inputs. Does anyone know, if I fly it in ATTI, will this remove the compass input so i can see if its that?