Phantom 2 issues & crash

wms

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Alright, so I have a couple problems with my bird, just when I thought I managed to get it all up and running... A little backstory: I put together a Phantom 2 with H3-3D and a FPV setup. By put together I mean buying a stripped down Vision (without Wifi and camera), replacing the Tx and Rx for a regular 2.4GHz versions and adding the video stuff. It all took a while to build because parts are increasingly hard to come by where I live. Now on to the issues...

First of all, last week I flew this thing for the first time. Removed the gimbal and other video components, installed prop guards (this will be relevant later on) just to get a hang of it and not damage the expensive equipment if I crash. I calibrated everything and did all procedures by the book. Issue #1 - extremely short range. Antenna pointed straight up, I'm getting about 100-150 meters horizontal at like 20 meters altitude (not going to fly higher for now) if I'm looking directly at it before it flashes yellow for lost signal. Shorter when I cover the antenna with my palm or when the FPV monitor is installed. My guess is that the replacement Rx is not fully functional, I'll probably start off with replacing the Tx antenna for a bigger one. Maybe mod the Rx ones too? Any input on that?

Anyway, I can deal with the short range, the second issue is much more worrisome. This weekend I took it out to the field WITH camera & FPV installed. On my second flight it simply fell out of the sky while hovering from about 15 meters. It happened pretty fast and I'm half sure I had no control of the craft as it happened. When it crashed I lost video feed (the gimbal cable was partially disconnected on impact I guess), the engines were still running at high speed and it was not responding to any inputs - I had to manually pull the battery to shut it off. When I turned it on again it demanded compass calibration, which I did and it passed without issues.

I took it home to assess the damage and read up - luckily only the shell cracked in a couple places (it needs replacing anyway, I swear this drone is made up of 60% epoxy and the rest is electrical tape, honestly I'm sometimes surprised it even works) and there's no damage to the gimbal. Well anyway, I read up on VRS/prop wash and it could have been it, though I hear it usually happens when descending which I was not. At this point I removed the prop guards since apparently they amplify the problem. Doesn't really explain the lost controll, but 1) it could have been in combination with lost signal as per the first issue, and 2) in panic mode I probably only tried to increase power instead of trying to move horizontally - I'm honestly not sure of this one.

After fixing up the shell I took it to my backyard the next day. Again - did advanced calibration, compass dance, no prop guards, battery charged. Powered up my camera and took off. This time the plan was to only let it hover at about 5 meters and do little circles every now and then. Boom - a couple minutes into the flight it goes down again - this time I had control and was able to steer it away, but since the altitude was so low it still hit the ground - controlled crash I guess.

So, how do I deal with it? I was hoping the prop guards were the problem, but I still experienced a crash with them removed. The problem didn't exist until I mounted the gimbal and camera. I have video of both crashes which I have yet to watch, maybe I'll upload it to youtube so you guys can help me find the issue... Honestly at this point I'm tempted to sell it and buy a P3 or something, but holy hell I spent a lot of time on this one and I want it to work!
 
It's not going to be VRS unless you were descending to beign with. The only time I've experienced the P2 descending uncommanded has been due to bad batteries - that typically happens a couple of minutes into flight, probably when the voltage or current goes outside some specified range. I would suspect the batteries first.
 
I would recommend checking the battery. Is it holding a FULL charge? Also what radio gear are you using? It shouldn't affect the AC at the distance you are talking about but exactly how short is the range you have?
 
Hmm, I didn't even think about the batteries... I have two of them, one is basically done and I use it for tests when I make any adjustments, the other one charges fine and gives me about 15mins of flight time. It's not charged right now, should I just pop it in and take a screenshot from the Assistant to post here?

As for range, I'm using a DJ6 stock transmitter, and I've got blinking yellow lights as close as 50-60 meters away and 15 high, but sometimes it's fine at twice that much - haven't really flown further yet, you can guess why.
 
Yes that screenshot would help. If there's a bad cell it could be giving you wrong readings. So are you on 2.4Ghz with a single or twin aerial Rx? Sounds like you have an issue in either Rx or Tx so I would check aerial wires, joints etc
 
Okay, so:

This are my batteries. The first one is the one I'm flying (and crashing) with. Looks fine to me, but yeah, I'm not an expert on those things.
Second battery gives me about 3 minutes of flight time before it initiates emergency landing. Oddly enough, it also looks fine in the assistant, but it's a little swollen at this point so I guess there's no hope for this one.

As for the radio stuff I did check everything for mechanical faults but everything seems to be good. I imagine the Rx which I bought second-hand is the issue, but yeah I can work with that if I resolve other issues. After all adding an antenna connector is no big deal.

Here's the footage of that first crash. You can see it wobbles just a little bit and then goes crashing down:
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Looking at readouts for each cell the first pack which I assume isn't charged, looks OK but the second pack certainly looks to have seen better days.
There are a number of threads on here about P2 batteries so check them out. It might be worth getting a new one though. Just out of interest, the footage shows the front right prop guard coming into shot as the bird starts to fall. Have you flown it without these on? I ask just in case they have fouled a prop as they seem very flexible in flight
 
Sorry, just read that your second flight was without guards! Check all the motors spin nice n free by hand (disconnect battery or remove props!). After the crashes were all four motors still powered on?
 
Yeah, the 2nd battery is a goner and I no longer fly with prop guards.
All motors look fine to me and they were all still spinning after I picked it up.
I'm going to drop it off at a shop close by, I'm half decent with electronics but have little to no knowledge on drones. Maybe they'll be able to test it with different batteries and whatnot and figure out what's wrong.
 
Yeah, the 2nd battery is a goner and I no longer fly with prop guards.
All motors look fine to me and they were all still spinning after I picked it up.
I'm going to drop it off at a shop close by, I'm half decent with electronics but have little to no knowledge on drones. Maybe they'll be able to test it with different batteries and whatnot and figure out what's wrong.

Do you have mini iOSD installed in your FPV system? Without there is no way tell what the condition of the battery is. When the voltage drops to 10.6 it's more than time for that craft to be on the ground.

The screenshots you posted are useless and should have been taken after the batteries were charged. When you check a battery after charging you want to know what current levels are and there are three of them design, full and current on a new battery they should all be the same. The voltage all three cells fully charged should be 4 volts. Here are two examples:

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If you noticed there are a battery level warning threshold and a go home check box personally I leave that unchecked. The reason for that decision is the go home feature works the same way as the failsafe does so if you are under something and it senses a critical battery level it will crash. That is where having iOSD in the system helps. Here is a video that will show you the importance of having iOSD can be.

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Yeah, I don't have iOSD installed yet. I was going to buy it when all other issues are resolved. I'll check the battery after I charge it, but first I guess I'll wait to see what the guys at the shop will say. However my crash wasn't caused by the Go-home on low battery option, as you can see on the clip it didn't attempt returning or landing, just dropped like a rock... battery was almost full when that happened, too.
 
Yeah, I don't have iOSD installed yet. I was going to buy it when all other issues are resolved. I'll check the battery after I charge it, but first I guess I'll wait to see what the guys at the shop will say. However my crash wasn't caused by the Go-home on low battery option, as you can see on the clip it didn't attempt returning or landing, just dropped like a rock... battery was almost full when that happened, too.

That wasn't my point about the go home function.

The problem you are having is with the batteries and once you charge both of them you will what I mean even though one really useless the other may also be. Basically, it comes from not storing them at 50% when not in use for months and they should check from time to time to make sure they drained down below 20 percent.
 
That wasn't my point about the go home function.

The problem you are having is with the batteries and once you charge both of them you will what I mean even though one really useless the other may also be. Basically, it comes from not storing them at 50% when not in use for months and they should check from time to time to make sure they drained down below 20 percent.

I killed a couple of P2 batteries just like that.
 
I killed a couple of P2 batteries just like that.

You may store them at 50% but that doesn't they'll stay at that percentage for say three months. I am not buying any more OEM batteries at $122.99 when I can get two 5400mAh for $109.98 or $104.79 both with free shipping.
 
I see, I get your point. I have no idea how they were stored by the previous owner, but with one being useless after just 15 charge cycles it's not reassuring. Hopefully they'll be able to test it with one of their own batteries at the shop before I decide to buy a new one!
 
I see, I get your point. I have no idea how they were stored by the previous owner, but with one being useless after just 15 charge cycles it's not reassuring. Hopefully they'll be able to test it with one of their own batteries at the shop before I decide to buy a new one!

You could have tested the batteries yourself simply by charging both and checking them in your P2 assistant software. Word to the wise be care they may try to sell you new batteries at more than the retail price. Where do you live?
 
Poland, I know where to find decent prices here though. Yeah well, I hooked both batteries up to the assistant and looked at the health% status, which seemed fine to me. Apparently though it can be not enough or misleading if they're not being stored properly. Would you be able to say anything else from a screenshot of a fully charged battery? I have my stuff at work and would probably be able to post one tomorrow.
 
Poland, I know where to find decent prices here though. Yeah well, I hooked both batteries up to the assistant and looked at the health% status, which seemed fine to me. Apparently though it can be not enough or misleading if they're not being stored properly. Would you be able to say anything else from a screenshot of a fully charged battery? I have my stuff at work and would probably be able to post one tomorrow.

Post your batteries findings as you did before. Since your P2 is used I would be looking for aftermarket batteries like 5400mAh 11.1v as they plentiful here in the states on ebay for as low $54.99 usd.
 
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Right, so here's a screenshot with a freshly charged battery. Is that deviation on cell 1 that significant?
 

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