I am one of thoose who had a prop turn off. (Please you people who has flown rc aircrafts for 40 years and think everybody else is not worthy flying anything, dont bother) I did thighten The prop with My hands before takeoff. I have contacted dji for an adress to get the bird repaired. Nothing in two days! Not a word.  

However, please take care when flying without The proplocks. Dont fly over people or animals. A wind gust might drop the inspire.

"Note 2015-01-20: DJI has not replied to any request at all. No Customer action yet."

Weather conditions / how high were you flying?
Did that happen before or after DJI warned you about the prop locks? I'm trying to figure out if your case is the case they used as reference.
Thanks!

All I can say is got my inspire the day before yesterday and I have grounded my bird until all is resolved.

have you got a pic to put up with the prop off

I have to admit this issue perplexes me. Unless I am badly misunderstanding how it works, operating the motor should tighten the prop. And since the motors only turn in one direction, how could a prop fall off? Did the prop unscrew from the motor or did the screw come off with it? I'm not questioning whether or not it happened, I'm simply trying to understand what happened as it appers to defy the laws of physics.

abe@abekleinfel Posted at 2015-1-17 08:54
I have to admit this issue perplexes me. Unless I am badly misunderstanding how it works, operating  ...

when motor spins, the self-tighten design of the thread does tighten the prop and it should not fall off. However, when the motor suddenly stops, the momentum of the prop will make the prop keep spinning, which is same as losing the prop. the Inspire prop is heavier than the phantom ones, so the momentum is bigger. And a un-smooth slow down of the motor could also result the same. and the cause of un-smooth slow down could be sand in motor, gust wind and etc.

So tighten the prop securely is very important at this point before the new lock is available.

Normally, the motor's directional turning WILL tighten the props, however if the prop were to STOP suddenly (such as if the motor seized up or a twig got caught in the motor), then the motor would stop but the prop would keep on turning due to its inertia. If the motor stops and the prop keeps turning, it will quickly unscrew itself, and then it's lift will lift it right off the heli.

This could, apparently, also happen without the motor actually stopping, but just slowing down significantly due to the hell attempting to correct form a strong wind gust. The motor slows down, but the interim of the large prop keeps it turning faster than the motor (there is a lot of energy stored in a fast turning prop). This would have the same effect as unscrewing the prop.

This wasn't a problem with the previous Phantoms, as the prop was smaller and lighter (less inertia, less energy) and also had a larger prop shaft, which held the prop tighter with more surface area.

Does that help?

Best,

Ben

ben@primeimagem Posted at 2015-1-17 09:19
Normally, the motor's directional turning WILL tighten the props, however if the prop were to STOP s ...

Yes, it makes sense, though in all my years of flying RC stuff (planes, helicopters, Phantom, Inspire) I've never seen a motor seize up like that. But yes, I suppose it's possible. It seems that a prop lock would not help at all if the motor seized up. It would only help in the case where the prop spins off a still spinning motor, which I'd have to see to believe. And I'm sure we will see it since it seems everything, irrespective of probability, ends up on YouTube at some point :-)

DJI-JS Posted at 2015-1-17 09:16
when motor spins, the self-tighten design of the thread does tighten the prop and it should not fa ...

Thank you, good explanation!

yes,thanks for the explanation.

I keep hearing an echo in here.

Hej, I would actually like to hear more from you since this happened to you.   What were the circumstances that this occurred?  We want to make sure that other users do not experience this issue.

Tahoe_Ed Posted at 2015-1-17 14:55
Hej, I would actually like to hear more from you since this happened to you.   What were the circums ...

This happened before DJI was telling everybody about The problem. Would not have the bird in the air If I knew.

The inspire was i god shape before the incident. It had not been in contact with anything with the props. I had just made an IMU calibration as recommended to get rid of the yaws when letting the the sticks go. I was going straight up and released the sticks probably at the same time as a wind gust, not a really strong one, hit the inspire. Then the craft came tumbling down.  So it was not in contact with any branches or anything.  Before start I did a flight check with compass calibration and also, I did hand thighten the props.

This is a lovely bird, and I hope I'll be able to repair it. It's actually still flies but the landing pods are broken and the knee on one side at the end of the rod for transforming is broken. Camera works, gimbal works, motors works ... Everything . But I would love to have the inspire repaired in a dji repair shop so they can have a look for anything that does not look right.  I just missing a address for the repair shop

I have some jobs where the inspire was suppose to help out. I am a fotographer. But my friends phantom will have to suffice for now.

Anyhow, there is a slight changs that the props can come off, even if you do hand thighten the props. That's why I recommend, do not fly without prop locks it's a lovely bird, don't let your impatients make you fly. Having it sent for repairs suck a bit.

May i use this ?

Blip Posted at 2015-1-17 08:20
Weather conditions / how high were you flying?
Did that happen before or after DJI warned you about  ...

It did happened before the official  announcement from DJI. I was at 100 meters, the wind was about 6m/sek and 10 - 12m/sek in the gusts. No rain, snow and about 6 degrees celsius. I do not believe my case was the reason to why they made the announcement but I am one of those telling DJI they where right in grounding the birds until proplocks comes.  

According to DJI (shown below), the E800 motors on the Inspire 1 uses closed-loop control ESCs that will activate motor braking when required. This type of braking may cause the props to come off in some circumstances like strong gusts, quick movements etc

Phantoms (E300) and E600 motor-ESC systems do not employ motor braking on their control system, resulting in the self-tightening props being safer.

I have no idea why DJI employed self-tightening props on the Inspire 1 if they knew that motor braking may cause the props to come off in some circumstances.

http://www.rcgroups.com/forums/s ... 3871&postcount=3508

"E800 and inspire use close loop ESC and apply active brake on the motor. If you did not screw the prop in tight as it required, the prop may fly off in some circumstances.

E600 use traditional open loop BLDC approach, with absolutely no brake, so self-tightening props is 100% secure on it."

Hope this was insightful (it was to me anyway even though I'm not a electric propulsion Engineer, I really appreciate DJI giving some technical insights into these issues).

shameful design and Dangerous to fly. what can we do? using super glue and kick off hard case? or change motors and props?

DJI recommends grounding the Inspire until propellor locks are installed.

Hmm.. perhaps self-tightening props was a bad idea on the Inspire and should be completely replaced with a better design instead?
It is better to mitigate a hazard by process of Elimination; not slapping on more equipment. The propellor locks may be a short-term fix until Inspire 1 (ver 2) is announced (pure speculation).

hej, I admire your great attitude about the whole thing.  

If you haven't found a place to get it repaired I'd go on their online chat thing and ask.  http://www.dji.com/info/news/24-hour-technical-support-inspire-1

Hey, I'm one of those 40+ year pilots and after flying 3 Phantoms since the P2 versions came out, who only spins on my props, would have bet money that this couldn't happen.  But your experience is a fact, so then we engineering types have to dig for understanding.

The only reason this is happening is that the Inspire has dynamic motor braking, a feature not used in multi-rotors before, maybe a first I think.  This can give the model greater agility and stability in wind etc since the motors can now speed up and slow down quickly.  The mass of the larger prop coupled with the brake is allowing this spin-off to happen, but I've watched every video I could find along the way and even with extreme flying this never happened.  Your flight description sounds so mild, it must have blown your mind!  I'm glad that the damage not major and really glad that folks like you came forward and got this issue visible and that DJI came up with a fix so quickly.

The thing about hardware, stuff happens!  Sharing detailed descriptions of exactly what happened, how high, how fast, wind, and what you were doing at the time are so very helpful to quickly finding root causes and saving others like me some grief!

Well I'm glad that DJI is fixing this issue with locks and not to trying to compromise the Inspire's performance by toning down the motor's deceleration.  I'm not an expert in the mechanics, but I'm guessing the chance of props coming off can also be lessened if the motor doesn't brake too abruptly. But then again I'd rather take the extra step in screwing on nuts and bolts than to sacrifice the agility of the Inspire.  Consider this a complement to DJI in spite of the inconvenience for the wait.  I hope DJI maintains the Inspire's flight performance in any future firmware updates.  That includes the speed.

Man oh man my heart goes out to you guys. I came within a hair of preordering one of these to add to my quad filming fleet.

I rarely ever preorder anything due to these kinds of things. Seems like there's ALWAYS some tweak needed after the fact. BUT good lordy this takes the cake for technology turd release of the decade. I mean think about it... "Dynamic Motor BRAKING" with "Self Tightening Props".  For gods sakes these are "Engineers." You think somebody in some DJI meeting would have said, "uhhh... Isn't this combination kinda like like gasoline and a spark?"

You think somebody in some DJI meeting would have said, "uhhh... Isn't this combination kinda like like gasoline and a spark?"

This would be a good example of the Chinese educational system versus the U.S. It's a well known fact that the Chinese are great at memorizing complex mathematical sequences and formulas. On the exterior they appear to be very educated and smart. No doubt they are. However what is lacking in their educational system is free will and free expression as well as a lot of creativity. In the Chinese society this is not encouraged like it is in the U.S.

"Thinking out of the box" is quite a bit different in China compared to the democratic nations of the world. Sure it seems like I'm stretching here, but I'd bet there's some connection here - especially something as critical as "spin on tightening" propellers air breaking.

reme Posted at 2015-1-18 04:16
Hey, I'm one of those 40+ year pilots and after flying 3 Phantoms since the P2 versions came out, wh ...

Yeah, I do tell the story in detail because I want people to know what can happen, and I do not need to get a free repair by twisting the truth. I'll bet if I tightened the props REALLY hard, this would not happen. But I did  a check of the propellers before flight. I did go straight up to 100 meters, slowed down, and the prop went off.

But please remember, the bird is an fantastic machine. I am a photographer and I love the different possibilities  it has. When they have the bugs shortened out, this will be the best thing ever (so long)

rizal Posted at 2015-1-17 17:19
May i use this ?

I think this product would be better As it can be removed easily when needed.

hej@mgns.se Posted at 2015-1-17 16:24
This happened before DJI was telling everybody about The problem. Would not have the bird in the a ...

Sorry for the loss,
could your export the flight data, and send via email with the accident video to Inspire1@dji.com ?
we will check whether belong to product issue and follow support procedure.

Hi inspire 1 pilots,
After reading all the tweets, it looks to me, that just one ore two people had the problem of loosing there probs. (of whatever reason). But DJI and many others for sure fly around since weeks without this specific proplem. So if i handtight the probs really propper, it shouldn´t be a problem!?
For sure DJi sends out a warning not to fly, but if i would be DJi, i would do the same, just for precaution reasons. They want a inspire 1 out there what is easy and safe to fly, even when you are not thight the props a 100%.
Someone shares my opinion, or do you think i am on the wrong way.......

DJI-Dboy Posted at 2015-1-18 15:34
Sorry for the loss,
could your export the flight data, and send via email with the accident video ...

DJI-Dboy: I have done this. I sent the data to the support last night. I am afraid I can't find the card with the video on it. It disappeared in the fast landing.  I am happy to give you anything to help you refine this fantastic bird!  And for me, I just want to get it fixed. If you think this is a warranty thing, great but if you still don't believe that I hand tighten the props, that is fine to. Just telling what happened to me so you can compare to other incidents and make a pattern from it.  Before flight I do hold the motor with a pinch and twist the propeller a little extra after spinning them on. It is not like i twisted my knuckles white because I am afraid something will break.  ;c)  So I just want my Inspire repaired and the proplocks. Time is money so I rather pay for the repairs then wait for a investigation.  :c)

jhannon66@gmail Posted at 2015-1-18 01:41
hej, I admire your great attitude about the whole thing.  

If you haven't found a place to get it r ...

Thanks! Kind of you to say.  :c) The support has been contacted and they have asked for flight logs which I did give them. They are collecting data to understand us users and the things we are doing to the units.   On Monday they will tell me where to send my Inspire.

martin@tomczyk. Posted at 2015-1-18 16:13
Hi inspire 1 pilots,
After reading all the tweets, it looks to me, that just one ore two people had  ...

Just telling you the story.  I do understand that people will think "Oh, he did not tighten the props, he is not a real pilot" (I Did tighten them but was it enough? ).   Of course, most of the inspires will NOT drop the props. But in the "right" combination it just might. Therefore, the DJI solution of sending out proplocks is great.

Before posting my story on the forum I thought to my self  "Now everybody will think I am an idiot" but I am willing to take that. Maybe I'll make some people to give the prop even an extra twist and save the bird.

hej@mgns.se Posted at 2015-1-18 18:12
Just telling you the story.  I do understand that people will think "Oh, he did not tighten the pr ...

hej
thanks for reply. its not about blaming someone of doing somethink incorrect. i just wounder if you are the only one who had the problem.
I got my inspire four days ago and can´t wait until i can get it in the air. So i just want to figure out, how serious the problem really is.
At the end, we all want to fly safe and as soon as possible....

martin@tomczyk. Posted at 2015-1-18 18:30
hej
thanks for reply. its not about blaming someone of doing somethink incorrect. i just wounder i ...

No, I am not the only one who has this problem. They knew about the problem when I reported mine incident. How common it is? I do not know. It has only happened once for me anyhow.  ;c)

I appreciate you sharing this with the group and DJI.   I would consider keeping it to myself, as you stated, but it's best for all if these things are reported - so 'thank you'.

I've seen a few reports on the one of the Facebook groups of this happening to others.  Seems to usually be due to high wind gusts causing the Inspire to brake it's motors aggressively.

I was waiting for a sign from DJI Germany today about where to send repairs but I am afraid there is no sign of action right now. That is a bummer cause in a couple of weeks we are starting recording a commercial for a company in Scandinavia and time goes by. I was hoping we could practice with it before.  ;c)

A reflection: It was stupid of us to go for a brand new, untested platform when we really needed to have something that works so soon. But lesson learned. Its a nice machine but there are no spare parts and no one to repair it. Its not for a pro environment yet. It still flies so we might have to shoot with a Inspire having a slight  "limp".  ;c)

hej@mgns.se Posted at 2015-1-19 22:52
I was waiting for a sign from DJI Germany today about where to send repairs but I am afraid there is ...

You are all missing the big picture - the props that come with the Inspire are garbage. Why do you think there are 2 screw holes in the top of motor and the shaft(pin) is so small - Hmmmmm.... Could it be that there are other props out there that center over a small pin and use two holes to mount to motor ?  Another hint - search "T-Motor Props".   Order soon, they'll all be gone tomorrow.

Hi

This same thing happened to me. The prop just flew off during mid flight 100 feet in the air. I sadly watched it fall to the ground and break to pieces. I sent it in today. Hopefully, I don't get a run around.
FYI: I build octos and hexas for a living professionally, so I could care less about any amateur talk.
Also there was a gusty wind during the flight. I initially thought this was impossible with the self locking feature but my eyes don't deter me.. I thought I was the only one that could of faced this issue.. All prechecks were done and I was safe to fly after calibrating the sytem... Is this issue fixed??

For those of you that have suggested using a thread lock, please do not.  They can destroy plastic and are not recommended.  If you choose to fly then firmly hand tighten your props and avoid aggressive flight especially in windy conditions.  The prop locks should be available soon.

paul.swieconek. Posted at 2015-1-21 05:41
You are all missing the big picture - the props that come with the Inspire are garbage. Why do you ...

Don't give the the half empty glass advice - fill the glass up with the best suggestion. We are not mind readers just quad lovers.

joeztan Posted at 2015-1-17 21:49
According to DJI (shown below), the E800 motors on the Inspire 1 uses closed-loop control ESCs that  ...

Exellent bit of info here , never would have guessed this new motor braking esc , interesting , Thanks
For sharing this !