Another Phantom Fly Away - IMPORTANT

[swisser]

CameraGuy,

Sorry you suffered a crash. You only lost your ND filter as you say, but regardless, it's an expensive nuisance and I don't envy you the agonising time of watching it fly out of control.

As to the cause, and your next steps, I think you need to take a rather more scientific approach. Your video suggests that this was not a typical fly away whereby you lose the ability to control it due to a bad link between RC TX and RX. Had that been the case then switching the transmitter off would have meant it would have returned to home. People are talking a lot about TX and RX, power line interference etc. and all of those things are interesting and worth considering in other circumstances, but they don't match up to your experience. If you do seriously suspect those, and personally I think you're wasting your time to do so, but if you do, then you need to TEST it. It would be very easy to test if you've got a friend and both of you have a cellphone with a headset so you can talk to each other.

Instead, you need to ask yourself how a prop came off, without the hub of it being damaged, in the crash. This could only have happened if it was loose at the time of the crash. If you found the prop near the crash site then clearly the prop didn't come off when you first experienced a problem, but it might have been loose then. I'm not familiar with the phantom but if the prop isn't attached securely can the spindle spin without the prop moving at the same rate? If so then I think you have your answer as to what happened.

I don't think this is a systemic DJI issue - many people can testify that the fundamentals of their flight controllers, and the return to home function, works very reliably in most cases. The times when it doesn't are usually related to ancillary equipment, but clearly in the case of the Phantom this wouldn't be the case. Clearly they can and do go wrong, but in this instance I think you're barking up the wrong tree.

Hope that helps.

 

[rdalemercer]

No, the GoPro wireless was not turned on. I too read that quote, and it was turned off.

Many people think it's the cheap transmitter that is included in the package, and the cheap radio. While I am loathed to spend more money on this thing, I will purchase a Futuba J8 this week to see if it improves things.

DJI has yet to respond - what a surprise.

Darren

CameraGuy.
Great! I had hoped that you (and others) had seen and read that comment from DJI.

Re: the "brand" of Tx to buy - Everyone wants to think that their particular 'brand' is the cat's meow - and it probably is ... for them.

My only comment on this subject ... (caveat) ... if this is your *first* Tx purchase (I don't know your level of experience with this hobby) ... is to buy the brand of radio that people in your local flying club that also fly the Phantom / multi rotor (that uses NAZA/WKM) use as their daily Tx. In this way, you can be somewhat assured that you are going to get competent help from those members that are more experienced than you are. In turn, you will be able to help the new generation of pilots as they get introduced into the hobby.

...my .02

Dale.

 

[DennyR]

I was testing one of my small Naza/quads on the RTH and obviously I did not have enough sats. when I took off so it came home to the wrong place. Took me 40 mins. to find it as it flew over a road into a taverna area. It landed ok in a car park, but when I got there some kids had stolen my GoPro.

 

[CameraGuy]

Now that sucks about the gopro.

The reason I am talking about the Futuba is because it was recommended by someone on one of the threads and has a diversity receiver with an s bus. Locally,the prevailing radio's are Spectrums, but I don't think they offer the same level of performance as the J8 I was recommended. I am open to other thoughts though. Today is my day to place my order with the local hobby shop to receive it by the weekend, when I have a trip planned to a 1000 acre farm with family.

 

[CameraGuy]

I would like to blame operator error, and say it is the prop nut that was loose, but I'm pretty good about those things, so I don't think it was that. I can tell you it is on my list of things to check now every time I fly. I will be testing and doing a longer preflight than flight at the rate things are going wrong.

DJI doesn't want or intend to comment it seems. It is disappointing. I lost one already. I can't afford to loose a second one.

Thanks for your thoughts. I'll keep them in mind.

Darren

 

[Kilby]

I seriously doubt it's a loose prop nut. The stock DJI props have slotted hubs, so even if the nut came loose it would still spin at the same rpm, although off balance. If that happened, it would start bouncing around in the sky and you would know 100% that something was wrong. Once the prop nut came off, it would fall out of the sky like a brick. I don't see any signs of that happening in your video.

You are having some type of interference of one type or another. The trick is to find what it was. The power lines and apartment building is a huge flag and good place to start looking. When you had the last one fly away, were you flying in the same location?

 

[sixshooterstang]

I was testing one of my small Naza/quads on the RTH and obviously I did not have enough sats. when I took off so it came home to the wrong place. Took me 40 mins. to find it as it flew over a road into a taverna area. It landed ok in a car park, but when I got there some kids had stolen my GoPro.

Not enough sats? it doesn't take but a half minute to get green on DJI equipment because of the internal battery. The ublox gps module on my APM usually take ~15 seconds to get 8 satallites but if you take the battery out it takes 5 minutes to get a good lock. You sure the battery isn't knocked loose?

 

[swisser]

The stock DJI props have slotted hubs, so even if the nut came loose it would still spin at the same rpm, although off balance.

Fair enough. Though I think you should still be asking yourself how the prop came off in the crash, if the prop hub wasn't damaged. Just think about it - a nut doesn't work loose in a crash.

As for radio interference the only thing that will prove or disprove that is to actually test it.

 

[Cheshirecat]

Just to throw this in to the debate, i changed the receiver on my Phantom to a Futaba S-Bus receiver and use the same Futaba 14SG that i use for my SkyJib. It is relatively straightforward to do if you follow the YouTube instructions http://www.youtube.com/watch?v=jRUDKZGhwuU

In no way related to your issue, I also replaced the stock motors with T-Motors and (balanced) Carbon reinforced props. The performance is so much better and responsive especially being able to adjust the gains in flight. I can't say i have ever had a loss of control with the stock radio but when you see the receiver it is easy to see why it might not be very well featured, if you get an S-Bus receiver you can even use the same cable.

Good luck, i hope your experience improves

 

[cootertwo]

I know this is an old, old thread, one of many about fly away's. But of all the videos I've watched. quite a few seem as if the phantom was took off, "before" it had time to "lock home" position. With both of mine, old ver, and ver 1.1.1, it can take around 2 minutes or so, to get the "rapid flashing green light" which, as I understand it, indicates it has locked home position. I fly around my 1 acre, under a tree cover of about 40/50 trees, so I seldom get 6 or more sats, but I always wait for the rapid green, before I take off. And I am amazed that I can sit on my back deck, and fly FPV, all the way around my metal mobile home, out and around, behind my barn, low to the ground, and have not had any interference problems, either with the phantom TX, or my Immersion 600mw video TX. But yes, I still get that empty stomach feeling if I go high, wondering if the day will come that I have to watch it "fly away". Imagine the size of the RX on one of the "micro" jobs that fit in the palm of your hand. And they have some range to them. Just sayin.

 

[R_Lefebvre]

Wait, there's a DJI flyaway thread on the internet that Lucien hasn't been shilling on?!?! :highly_amused:

 

[TheUFGadget]

Can you please provide a spectral scan of the field you were flying at? Have you made sure that there are no conflicting radio frequencies in the area? These are things that can also impact your phantom regardless of your pre-flight check list. It may not be a product of your unit or your ability to prepare it but your ability to analyze and pre-flight check your field. If you can provide that we can help determine if your field is hazardous and possibly rule that out as the cause of the fly away.

 

[R_Lefebvre]

That sort of thing really should not be required to reliably fly a multirotor with a proper flight controller.

 

[TheUFGadget]

That sort of thing really should not be required to reliably fly a multirotor with a proper flight controller.

You are correct! Great news. It isn't unreliable! He can reliably fly it, just so happens that an external factor has presented itself to hinder performance. Just because you have a radio in your car should you always get your favorite station? No, because sometimes you're in a bad area or the signal can't reach you because of a building blocking etc. If you are going to be doing any flying in "busy" areas then you need to scan that area to make sure it is safe. DJI provided and EXTREMELY reliable craft that as a stock set up and no interferance will be COMPLETELY reliable. The problem is that in today's day and age there are frequencies everywhere! If he can identify them we can help him shield his craft and have a pleasant flying experience so this doesn't happen again. It's the way you SOLVE them not hoping they will change.

 

[sk8brd]

let's also not forget about solar flare issues.

 

[R_Lefebvre]

You are correct! Great news. It isn't unreliable! He can reliably fly it, just so happens that an external factor has presented itself to hinder performance.

Or, or... there's a bug in the software that causes some of the flyaways? No, that would be unpossible.

Just because you have a radio in your car should you always get your favorite station? No, because sometimes you're in a bad area or the signal can't reach you because of a building blocking etc. If you are going to be doing any flying in "busy" areas then you need to scan that area to make sure it is safe. DJI provided and EXTREMELY reliable craft that as a stock set up and no interferance will be COMPLETELY reliable. The problem is that in today's day and age there are frequencies everywhere! If he can identify them we can help him shield his craft and have a pleasant flying experience so this doesn't happen again. It's the way you SOLVE them not hoping they will change.

It should not be required for users to scan for interference before flying. The system should be immune to most of it. And if the intereference is just too great, then it should do something intelligent about it, other than just flying away. It's just that simple.

Other systems can do this. Can't DJI's?

 

[TheUFGadget]

Oh man it's that easy?! holy cow! Great send us the fix!!!!! It's because it isn't a bug in the software.

So it's not your responsibility to look for external factors that would prevent your system from performing correctly? Hmmmm...So because it's wet out I should not slow down? I shouldn't do a pre-flight check? I shouldn't take my heart medication since other peoples hearts are fine? What you are doing is passing the blame, which is a product of today's society and also the hindering anyone from helping this gentleman in need.

You can troll as you are, but don't be upset when noone cares. DJI has made the phantom so that you can use their product flawlessly under the right conditions, all products are made this way. If your watch is not waterproof you don't jump in the water... ALL RADIO FREQUENCY technology is prone to interference...even our toughest military products. To expect that there are no external factors that will affect any products is pretty ignorant. At least that sheds light on to why you feel the way you do. I hope, only for the safety of others, that you will scan your flyign field so that whatever you are flying does not cause property damage OR damage to people. As hobbyist we need to be above the name calling and the finger pointing and take a level of responsibility. I genuinely would like to help the gentleman with his problem, but just because his aircraft flew away does not make it DJI's fault. Have fun flying!

 

[sk8brd]

i recall colin guinn making a video about a software update to help flyways if caused by interference i'm not much of a flight controller specialist but maybe someone that is could explain. i for one have had great experience with naza's on several crafts no issues knock on wood. i have seen people not wait for full sat lock before leaving the ground or failing to calibrate compass before though and have issues. There has been some very experienced guy's that have had problems though, due to what i don't know. There has been bugs in the past with some wkm software where people have lost crafts it looks likes those issues have been resolved though.. So to say that a bug is without possibility may be a little overzealous. Dji has admitted that there was some compass issues related to some wkm's on s800's that were fixed with updates. Here is the video about the updated naza firmware regarding interference problem's from colin guinn.. http://www.youtube.com/watch?v=GBmsQnS1ASQ i am a dji flyer btw and have been happy so far with these flight controller's and am by no means a dji basher so if i come off that way it's incorrect.

 

[TheUFGadget]

HI Sk8brd!!

Thanks for interjecting I would agree...to say it's 100% not is overzealous. I think to assume that it is has the same meaning as well. My point was that every product has its kinks and like you I have amazing experiences with all (5) of my Naza's and aircrafts. I brought up the spectral scan because when I range tested for a long TBS discovery flight I noticed that one park was emitting wierd signals...just so happened they had equipment that was emitting frequencies that would have messed with my LRS! Glad I checked . I think we all have to meet in the middle and be a very helpful group. If a companies products are really that bad then we should all boycott and have a powerful voice. I think DJI products are wonderful though!

 

[dazzab]

Well, what I consider the _real_ issue here is that no one will ever know if the issue is software or not because it can't be inspected and DJI won't discuss the issue. It's those factors that keep me from buying their products as I just won't trust expensive equipment to a flight controller that I can't get any feedback about if things go bad. What really surprises me about this thread is that the OP says he's using his second Phantom. It's really a shame as the copters I see using the Wookong generally fly very well. I'd love to know more about them and the people who achieved that level of performance.