Pretty sure DJI put a little more thought into designing this battery. It is basically the same design (an additional cell) as the P2 battery so it is time tested.
Fell Out of Sky - Total Loss
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This is exactly what I'm trying to explain. This is a big issue in the "so intelligent" battery firmware. I repeat that no technical reason exclude to use a not-fully-charged battery. BUT IF autodischarge is in progress, then only a battery recharge will stop it ! This make sense about DJI raccomandation, and obviously this is a workaround.
But it's not dimonstrated that an issue like this is real....
Some have said if you push the button to check it that it will reset the discharge timer. If thats true your theory would be incorrect. It's too bad they don't provide more documentation on the batteries. The P2's have flown for 2 years with the same design battery.
It's all speculation but I don't think the auto discharge is actually kicking in... I think it's a case of the battery reporting incorrect charge if a person flies after an auto discharge and not putting the battery on a charger. That is, the battery is actually around 60% charge (which should be fine) but the firmware reports that it's at 10% or 0% so the battery turns off... or the firmware just turns the battery off if it's not placed on a charger after auto discharging.
His info is not automatically incorrect. What I (and others suspect) is that the firmware might not be correct. While pressing a button still stops the auto discharge, if the battery is not then placed on a charger the firmware might turn off the battery during flight.
I don't think that pressing the battery button stops the auto discharge if it's in progress already, but it does re-set the timer that counts down to when it starts if it hasn't already.
At least for me, the intelligence is not in the battery but with the owner. If you can't be sure whether to fly on a partially charged battery, then don't... Just pop it on the charger, grab a beer and wait to be safe [emoji6]
At least for me, the intelligence is not in the battery but with the owner. If you can't be sure whether to fly on a partially charged battery, then don't... Just pop it on the charger, grab a beer and wait to be safe [emoji6]
I have a P3A, was recently in St. George, Utah on Thanksgiving Day. After 43 second of flight, 192ft of altitude gain and at a distance of about 1150ft, with about a ½ second warning (Voltage Error), it fell out of the sky. Fortunately, we were following all the rules so my brother who was spotting for me knew right where to find it. Unfortunately, it was tattered (to say the least). The battery was 100% at take off, there were no errors prior to take off and weather conditions were favourable. When I contacted DJI, as per usual, they provided and RMA and upon inspection decided it was a warranty service and tomorrow my bird will be back home.
It begs the question though, why does this keep happening to folks? I'd love to know what the problem was they fixed (beside all the broken parts). My wife freaks out at the thought of one of these coming down on someone walking down the street or onto a car parked or otherwise. Up to now, I'd not really thought about that...
Bottom line, you're not alone. Call DJI and submit it for repair.
It begs the question though, why does this keep happening to folks? I'd love to know what the problem was they fixed (beside all the broken parts). My wife freaks out at the thought of one of these coming down on someone walking down the street or onto a car parked or otherwise. Up to now, I'd not really thought about that...
Bottom line, you're not alone. Call DJI and submit it for repair.
Yep, the only problem I had with my P3P was when I took off with a 54% battery. It fell out of the sky from 200ft like a rock. It was like the power switch was flipped off.
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And i'm wandering of all the cases that the battery was 100% at takeoff, the bird has hours of no prob flights, & all preflight protocols were followed did the "power failure" happen seconds into the flight like yours, mine & many others. Seems to be a pattern! (Or not)
I said that based on my tests. But once discharge starts the only reset is a charge. Unless of course you drop the battery from 300 feet after which point the subject is moot.
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It definitely kicked in on my case. There's a battery history log you can bring up in the dji go app where it actually tells you the battery has gone into storage mode. So the app IS in fact aware. At this point the go app SHOULD refuse to fly but does not. That is the liability failure that dji currently owns. They can fix the problem later if they prevent these dangerous flights. Plain and simple.
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So where in the Go App is the log? Could I put my iPad on iTunes and get the logs for analysis somehow?
Does anyone really know what the design of the battery (supposedly intelligent and it has firmware that is updated when we upgrade flight firmware) really is? I need to research how batteries know what there charge is and how accurate that can be done. It appears that it's not too accurate or the firmware of the battery may be causing these issues. One thing I do know is that battery voltage drops as these batteries are used, we can see this on the GO app. I've seen where I'm in a latter half of a flight, and I give a lot of stick the voltage goes from green to orange. This happens because battery voltage drops when batteries are being heavily drained and under maximum load conditions such as when the motors rev up to 100%. If battery voltage drops too low, electronics stop working. This means it crashes, and that is what is happening. Is there a way to get voltage vs. time from logs on these birds?
You have to have the battery in question in your bird I believe. Here's one of my batteries currently in this state and the history log showing it knows it's in this state. The bird would allow me to take off right now and likely would crash to the ground within a minute of takeoff. Current battery state is almost identical to the night mine shut off the lights and crashed to the ground.
The app clearly knows it yet gives safe to fly. If you see this message under a battery you are about to use STOP!
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Thanks for that. I think that's a new pre-takeoff check - note battery condition and view the logs.You have to have the battery in question in your bird I believe. Here's one of my batteries currently in this state and the history log showing it knows it's in this state. The bird would allow me to take off right now and likely would crash to the ground within a minute of takeoff. Current battery state is almost identical to the night mine shut off the lights and crashed to the ground.
The app clearly knows it yet gives safe to fly. If you see this message under a battery you are about to use STOP!
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So as a precaution to avoid these dangerous crashes from low batteries, I'd also do these three things.
1. Set discharge to 10 days (lowers probability of being in a discharge condition)
2. Charge fully on the day of flying, just before takeoff. Do not fly on a low battery.
3. Easy on the stick - less current is easier to deliver than max throttle or control input
Set them on ten days if you fly a lot -- you don't want to leave them fully charged if they will be sitting for ten days without flying. Lithium batteries do store well fully charged. They need to be around 50% if you are not going to fly awhile.
I flew with 97-98% battery ,total shut down about 30 seconds into flight and crashed
Haven't had a problem since ,BUT???
...
The app clearly knows it yet gives safe to fly..
...
I don't agree. If you know you must fly with a full charge and you see this screen, you know it is not safe to fly.
I think you miss my point. The app has a couple ways to prevent the flight and does not. That's my point. I already stated there should be no flight.
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