Prop broke off in flight!

[Gizmo3000]

last night I crashed my Phantom into the neighbors yard, a buddy jumped the fence and retrieved it, but it had lost a prop and nut.
so tonight I put on a replacement prop (http://www.heli-world.com/detail.aspx?ID=10468) and bought a replacement nut and took the Phantom out for a spin.
seemed to work perfectly fine,. but towards the end of the flight, the prop actually BROKE off!
..it didn't just come undone, as the bolt was still attached!

Has anyone heard of this happening before?
might I have over-tightened the bolt to cause it to weaken or something?
defective blade?? (maybe it hit a bug??)
now I'm a bit scared to think what would have happened if the blade broke off hundreds of feet in the air.

Also, are blades supposed to be installed in pairs? (it's a bit awkward having 3 oem white blades and a black one, but they look identical)

 

[don c]

last night I crashed my Phantom into the neighbors yard, a buddy jumped the fence and retrieved it, but it had lost a prop and nut.
so tonight I put on a replacement prop (http://www.heli-world.com/detail.aspx?ID=10468) and bought a replacement nut and took the Phantom out for a spin.
seemed to work perfectly fine,. but towards the end of the flight, the prop actually BROKE off!
..it didn't just come undone, as the bolt was still attached!

Has anyone heard of this happening before?
might I have over-tightened the bolt to cause it to weaken or something?
defective blade?? (maybe it hit a bug??)
now I'm a bit scared to think what would have happened if the blade broke off hundreds of feet in the air.

Also, are blades supposed to be installed in pairs? (it's a bit awkward having 3 oem white blades and a black one, but they look identical)

 

[don c]

Hi,Gizmo,I bought a phantom three weeks ago.First four flites were awesome.Now the fifth flite I flew straight out about eight to ten feet off the ground a good sixty feet or so,pull stick back a bit to fly back to me,and yep both clock wise props snapped off,and down she went . these were the white props.I ordered two sets of props they were black.So I figured great give it a try.I put on the black props .and the same thing happened again,only one prop broke off this time.So here I am scared to fly my quad.With both flites the crashes happened at about one minute in to each flite.I was flying gentle,no wind.So here I have a thousand bucks tied up in the darn thing and can't have any fun.Anybody Know what I should do to fix my problem would be greatly appreciated.Regards Scaredtoflynow donc

 

[Gizmo3000]

Yikes!
I was kind of hoping that mine was an isolated freak incident. (and only with the black blade)
did yours break at the center as well?
I'd freak if it happened to me while my copter was a few hundred feet up and out (with camera attached)

I guess one option would be to consider the fancier (and way pricier) carbon fiber props sold here:
https://dslrpros.com/Products/tabid/94/ ... fault.aspx

Tho I was hoping to get more experience with plastic ones before splurging on those

 

[don c]

Hi,there,I contacted the dealer and he said switch to atti mode to see if I had to fight it to keep it stable.I live on northern Vancouver Island B C Can we get our share of rain so waiting for the weather to clear up .I thought I had the nuts to tight too.But know I don't think so.The props broke apart right at the motor shaft.A real loud bang like like the motors went in instant revers.One half of the prop was over sixty feet away from the crash so watch out I guess.I'd like to buy more batteries,but it seems everybody is sold out.Any help there?Talk soon

 

[Gizmo3000]

I honestly cannot see how instability could lead to prop snap (compared to regular/agresssive flying which I imagine can be more stressful on the components).
Mine snapped off in nearly dead calm nighttime weather. (also at the shaft, only found one half, unsure where the 2nd half may be)
(I also suspected that perhaps the prop might have somehow hit the housing, or the battery door opened somehow (but it may have popped open when the copter hit the ground)

There are a few threads here on the forum on where to buy additional batteries. (do a search). - where persons with much more experience can help ya out. (I'm as new to this as you are no doubt)

the Phantom brand ones are def seem sold out, however there appears to be a number of other dealers and manufacturers out there who made compatible batteries. (but you'd def want to make sure the connectors are correct)
i bought the "Century" brand and it seems to work just fine. like this one: http://www.centuryheli.com/products/pro ... pageid=895

Just google : 3S1P 2200MAH 20C Phantom
and a number of hits will come up.
(or only google 3S1P 2200MAH 20C )
a number come up on Ebay as well, I'd just go with the ones with the yellow connectors!
I believe there are other, higher power ones that you can get as well (35,. 45C).
like this one, if it's in stock https://dslrpros.com/Products/tabid/94/ ... fault.aspx

 

[don c]

donc here ,Thanks for the threads re bats.I just came in from a flite,I had it atti mode and all went well. have to recharge the bat.only one bat sucks .I find that when it's in atti mode once it gets going it just keeps on going kind of neet.I have two batteris coming from Hobby King that will take 14 to 45 days they said,(synergy I think the name was)The last flite was the seventh.I keep a log book on all my flites.Anyways I'm goin g to look at the battery threads,maybe I an get some quicker else where.Take care.

 

[Gizmo3000]

Good luck! Imagine you *might* be able to find a battery at a local hobby shop.

While flying ATTI no doubt puts less strain on the props, it's inherently more dangerous than flying in GPS, especially if you're flying in a confined space where things can get sketchy/disorienting.
-which is why flying in GPS is much more highly recommended for beginners, and truly one of the most brilliant features of the Phantom. (no way in hell I'd fly mine up 150 ft if I didn't have it).
I've been practicing by doing circle-8's with the Phantom moving away, coming towards me and flying sideways. - always in GPS.
if you're going to fly around with ATTI as a beginner, keep the finger close to the switch to turn GPS on as soon as things seem sketchy.
and hopefully the broken props were just a fluke.

 

[RallyPilot]

@Gizmo3000 and don c, have you used Loctite on the prop nuts? I have read that Loctite leaking to the prop material will destroy it.

 

[Gizmo3000]

@Gizmo3000 and don c, have you used Loctite on the prop nuts? I have read that Loctite leaking to the prop material will destroy it.

Nope, I hadn't used Loctite. (which is probably why my first, OEM prop came off one evening (before or after it landed in the neighbors yard).
Then I replaced it with a black-prop (which may or may not be DJI manufactured?), and that's the one that broke apart.

But thanks for the tip, as I plan to very cautiously use Loctite from now on.

 

[tanasit]

I don't think the ATTI or GPS mode has to do with the broken prop because there's no sudden jerk on the motor. The stock prop nut has a design that it won't go past the thread shaft and this I mean it will pass the thread section to the waist of the 6mm shaft but will stop when it comes into contact with the bottom part of the shaft which is 8mm. This is why when one use the Graupner e 8x5 prop whose hub has less thickness than the stock's, one has to either use the washer under the prop to raise the prop or insert the washer between the prop and the prop nut so that it can be tighten down.
As for the stock prop that not only has the thick hub but the hole is keyed so that you can hold the prop while tightening it down. This design is different than most of the other props on the market but it also has the weak point! You may over tighten it so easily and in the process create the fracture on the hub but not enough to break it right away. In flight it is a different situation. With round hole in other props, you have to hold on to the motor can to tighten it down and it is unlikely that you will over tighten it because by then the motor will start to slip and turn with the torque you putting down, which may cause the loose prop but not fracture the hub.
I think if the prop broke at the blade's root then it may be defective but if the hub broke in half or more pieces, then you probably over tighten the prop.
One may think he didn't over tighten the prop, but if you use a wrench and hold it at 5 inches or more from the nut to the handle a few pounds of torque may cause that. Let me give you an example, a friend of mine help me fix my car. We are replacing the valve cover gasket and while I was tightening down the nut on one end, he was working on the other. Suddenly, I heard a snap :shock: and yes he broke off the bolt. I then showed him that when we're near to the end of the turn, we should move the hand toward the head of the wrench to reduce the torque. After we replaced the broken bolt, he managed to snap another. :shock: :shock:
As for the loctite, I did use it but very sparingly and never experienced that it melt the prop!
I found this which is called,"Flex-Top Expanding Hex Locknuts" and works great.
http://www.mcmaster.com/?m=true#hex-locknuts/=ldphwt

 

[don c]

Hi all Donc here,been away for a while.I put a little locktite on each shaft and let the quad sit for a half an hour or so.Turn so that it is verticle so the locktite does not run down the shaft to the motor.This seems to snug up the nuts real good.Even when you take the nuts off and put them on again they seem to work better.About three weeks ago I sent away to Hobby King (China) for three turnigy bat.They arrived at the post office in fourteen daysI almost fekll k off my chair,like that quick,So am getting a lot of flite time in.They were around seven bucks apiece.so in all with the shipping cost it came to $26.82 So better than the place in Ottawa. @ $25.00 & out of stock.I have a lot of space so I flew up the road about four hundred feet or so in atti twenty feet off the ground.The quad starts to look pretty small by then,the flashing light also small.I fly inatti all the time,I find I can put the brakes on pretty quick or flip it in to gps mode works good too.Thats it for know folks talk soon Don c

 

[denodan]

Hi all Donc here,been away for a while.I put a little locktite on each shaft and let the quad sit for a half an hour or so.Turn so that it is verticle so the locktite does not run down the shaft to the motor.This seems to snug up the nuts real good.Even when you take the nuts off and put them on again they seem to work better.About three weeks ago I sent away to Hobby King (China) for three turnigy bat.They arrived at the post office in fourteen daysI almost fekll k off my chair,like that quick,So am getting a lot of flite time in.They were around seven bucks apiece.so in all with the shipping cost it came to $26.82 So better than the place in Ottawa. @ $25.00 & out of stock.I have a lot of space so I flew up the road about four hundred feet or so in atti twenty feet off the ground.The quad starts to look pretty small by then,the flashing light also small.I fly inatti all the time,I find I can put the brakes on pretty quick or flip it in to gps mode works good too.Thats it for know folks talk soon Don c

NEVER EVER USE LOCKTITE ON THE PHANTOM PROPELLER BLADES!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

A much better solution are these, much lighter and accually lock, so will never come off in flight.

http://www.ebay.com/itm/330868946142?ss ... 1439.l2649

Out of the other quads I have, the Phantom is the only one with the Nuts coming off in flight Problem.

The Problem with the Phantom, is even done up, the nuts never feel like that have tightened up properly, where my other quads they feel like they do up tight nicely, but not the Phantom, which is why they have the nuts coming of.

So got sick of the problem having to go through each flight and check the nuts, and yet still had one come off in flight, even after checking.

The above solution is great, they never come off and lock, and also save weight as they are lighter then the dome nuts.

 

[marcus2005]

the prop broke because is not balanced .the plastic prop need to be balanced when you put on the phantom :shock: and after 10 flight need to be re-balance or chek. DONT FORGET TO TIGHT YOUR NUT EACH FLIGHT :lol: EVERY prop need to be balanced PLANE,QUAD,BOAT,ETC a non balanced prop cause a little vibration. a balance prop rack cost 20$-25$ at the hobby store with this little investment you gonna save your money and your QUAD :mrgreen:

 

[denodan]

the prop broke because is not balanced .the plastic prop need to be balanced when you put on the phantom :shock: and after 10 flight need to be re-balance or chek. DONT FORGET TO TIGHT YOUR NUT EACH FLIGHT :lol: EVERY prop need to be balanced PLANE,QUAD,BOAT,ETC a non balanced prop cause a little vibration. a balance prop rack cost 20$-25$ at the hobby store with this little investment you gonna save your money and your QUAD :mrgreen:

http://www.ebay.com/itm/ANODISED-NUTS-M ... 51a90241e6

use these much better, no need to check nut after each flight I use the above and don't even concider using the dome nuts, they are useless.