Disaster!

If you think about it, if you were to build a quad from scratch w/no automation it would be important for all four motors/props to rotate at the same RPM & have identical & counter-rotating props. As RPM dips in any given motor you begin to lose lift on that corner, if it dips enough or too suddenly the aircraft flips.

I'm not sure if the PV uses motors w/built-in tach's (looks like it has enough wires, anyone?) but w/closed-loop feedback motor speed control combined with inertial mass sensors to detect XYZ movement & velocity, automation must monitor all the sensor & tach inputs to calculate corrections to the motor drives to maintain the aircraft stable. But if say there's a bad bearing that suddenly starts to bind then become free all in an instant, I wonder if the firmware would overreact which would result in a series of oscillations (too fast/too slow) which would look like a wobble? Another I dunno here, just thinking out loud trying to make sense of all these "dropped out of the sky unstable" reports.

Perhaps some of you who have experience flying Phantom-1's or similar aircraft can comment.

iDrone
 
My PV was one that fell from the sky on it's first flight but my response is to the Phantom 1 question.

I have probably 250 flights on my Phantom 1 at elevations up to 12,500 feet Loveland Pass, Colorado) and never, ever had a problem or even a hint of one. Don't get me wrong, I've hard landed it and learned the hard way not to fly it inside a rebar packed parking structure but that wasn't the Phantom's fault; I prefer to blame my wife. :cool: Other than self induced issues, that ship has been a flawless delight to fly and I've flown it a lot to film ski race training and other sports.

I'll be up front and say that the PV was a blast for the ten minutes it flew and I think they have the right model idea but there's definitely some problems that need to be resolved. I really want mine replaced so I can proudly own and fly it safely and with confidence.
 
Crap - I just ordered a PV and am now just reading all these issues with "sudden loss of power and dropping like rock".

Can I ask a stupid question - could this be due to the stupid battery setup they have made proprietary with the Phantom Vision. I'm guessing that in mid flight, somehow the connection between the battery and the prongs on the Phantom become unconnected. When I first heard about the Phantom Vision battery setup - my first question was: WHY setup the battery like that. If it somehow separates, power is gone and the thing will fall like a stone. Why couldn't they just setup a balance port an Xt60 just like every other craft????

All these incidents - doesn't it sound like that? I don't think it's a battery issue per say - if one of those prongs on the Phantom doesn't "spring" out to make full contact, that's the equivalent of unplugging the Phantom at elevation. Boom.

Thoughts?
 
Could be. They sound like total power fail faults. I'd point the finger at the electronic switch in the battery pack... In an ideal world we'd await an analysis by dji and a fix, but somehow I don't think they will be forthcoming...
 
gpauk said:
Could be. They sound like total power fail faults. I'd point the finger at the electronic switch in the battery pack... In an ideal world we'd await an analysis by dji and a fix, but somehow I don't think they will be forthcoming...

Good thought - I hadn't thought of that. How would you fix it? If it's either of the reasons we discussed - it seems way too late. That's a Serious engineering flaw and I'm not sure how you fix it at this point.

Sent from my Samsung Note 2 using Tapatalk 4
 
Wangta said:
Crap - I just ordered a PV and am now just reading all these issues with "sudden loss of power and dropping like rock".

Can I ask a stupid question - could this be due to the stupid battery setup they have made proprietary with the Phantom Vision. I'm guessing that in mid flight, somehow the connection between the battery and the prongs on the Phantom become unconnected. When I first heard about the Phantom Vision battery setup - my first question was: WHY setup the battery like that. If it somehow separates, power is gone and the thing will fall like a stone. Why couldn't they just setup a balance port an Xt60 just like every other craft????

All these incidents - doesn't it sound like that? I don't think it's a battery issue per say - if one of those prongs on the Phantom doesn't "spring" out to make full contact, that's the equivalent of unplugging the Phantom at elevation. Boom.

Thoughts?

My thought was similar except that I was thinking the vibration or some type or harmonic vibration may make those prongs vibrate in manner that causes intermittent connection. So far most of the power failure type incidents seem to occur in hover which might indicate a similar type of vibration while in hover. The switch might also be an issue.

One thing that does not seem to be correcting the problem so far though are the firmware updates which would point to hardware rather than software.
 
If it was something like that, then a product recall of the batteries would be in order....

I think there's a few of us considering modifying the battery pack, to use an ordinary charger with a balance port, and xt60 connectors to the aircraft....
 
gpauk said:
If it was something like that, then a product recall of the batteries would be in order....

I think there's a few of us considering modifying the battery pack, to use an ordinary charger with a balance port, and xt60 connectors to the aircraft....

Yeah that would eliminate some guessing. Has anybody done it yet?

Sent from my Samsung Note 2 using Tapatalk 4
 
But, at least in my case, it is not a complete battery failure because the props were definitely still powered when it hit the water. I could see water being splashed and thrown all over the place.

It seems more like a cpu failure or an individual motor issue. The two main battery power connectors are beefy enough that I don't think they would be easily disconnected. However, in the "Battery warning" thread, some people mentioned the two small contacts for the battery reading. I had cleaned those with CRC before first use and tested the "springiness" and all seemed in working order though.

I thought it might be because of that firmware update that cannot be done on the Mac, but UAVinsurance says he did the update and he still had the failure so obviously that was not the issue.

On a side note, I just got an email from Amazon that a replacement VIsion was just shipped. But I have to admit I have mixed feelings about it. Not sure I really even want to try it anymore. At the very least, I would never use it if there are people around.
 
Geert said:
Bmachine said:
But, at least in my case, it is not a complete battery failure because the props were definitely still powered when it hit the water. I could see water being splashed and thrown all over the place.

It seems more like a cpu failure or an individual motor issue. The two main battery power connectors are beefy enough that I don't think they would be easily disconnected. However, in the "Battery warning" thread, some people mentioned the two small contacts for the battery reading. I had cleaned those with CRC before first use and tested the "springiness" and all seemed in working order though.

I thought it might be because of that firmware update that cannot be done on the Mac, but UAVinsurance says he did the update and he still had the failure so obviously that was not the issue.

On a side note, I just got an email from Amazon that a replacement VIsion was just shipped. But I have to admit I have mixed feelings about it. Not sure I really even want to try it anymore. At the very least, I would never use it if there are people around.

Lucky you.

I still haven't heard a word not from DJI not from my dealer.

:(

Agreed, hence my post that this is not JUST an issue that can occur without the proper updates. If something random like that did fail then dropping from the sky can occur whether or not you get the updates done. We have had reports of both people before updating and after updating having these random drops. That's all I was saying.
 

Members online

No members online now.

Forum statistics

Threads
143,066
Messages
1,467,358
Members
104,936
Latest member
hirehackers