Oohhh Explain this one?!

SMP

SMP

Member
Roughly 25 flights no issues, 5 flights that day no issues. Waited for GPS lock and Home Position Record prior to takeoff. You can see it go into GPS mode and then roll to the left, motors go nuts trying to level... Naza Fail, ESC Fail?? Unresponsive to Atti/GPS/Manual, didn't get a chance for a fail safe but suspect that would have been unresponsive as well. Wobbled a bit but never rolled over, went into a steep fast dive into the only piece of concrete in the bloody desert... Couldnt see it hit but even at 200 yards away, heard it!!! Went nose first into the black and exploded everything nose to tail. Rippppppppped out Antenna mounts!!! Boards etc!! . Naza is the only thing that is intact (figures) ..dont really want to conjecture if it survived and the gps which did have a 3D Puck saved it!! Again intact may not mean it survived the impact. Micro SD was ejected 15feet away from gopro!! Sadly SD was corrupted but managed to recover up to the start of the fail sequence.

Uhoh... Heres where it starts!
http://youtu.be/oPVY3yB4iRM

The not so surprising conclusion.
View attachment 12005
 

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Lanzar

Lanzar

Member
Well the motor is overspining in video. And you can also hear this in our video. Hard to say what went on. Sorry for your loss.
 

T

tombrown1

Member
It looks like you were starting to right it just as the video ended. Sorry it turned out that way. If ATTI and Manual both failed I would think it would be some sort of motor or ESC failure.

Good luck getting up and running again.

TB
 

D

Dewster

Member
I think one of the props came loose and resulted in loss of thrust. That's the only thing I can image would cause the motor to spin like that without providing enough lift on the failing arm.
 

E

Electro 2

Member
Loose prop, no question. You checked prop nut torque before the flight ?? I always do, especially the counter-rotating ones which are more prone to backing off. Some guys Locktite 'em, makes it a pain to change props, but no back-off issues.
 

SMP

SMP

Member
Hi guys, thanks for all the suggestions! had a couple of good heads up about Electrical Activity but starting to think most likely culprit was prop starting to come slightly loose and slipping. Upon picking up motor debris was able to pull a prop nut off by hand, granted it was bent at a 30 degree angle and took some force but still should have been tight... Was running the Sunnysky motors with the stock adapters and had these on order http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=19586 but didnt want to wait. As Electro said, the prop check should have been done. Ironically or predictably, while we do this for all our larger birds this was the last battery of the day and we neglected to check. Pilot error pure and simple. No worries, gravity wins, build another :)

What we HAVE learned over a couple of mishaps is that when it goes wrong you have very little time to make the correct decisions. If they aren't either a habit or top of mind it's unlikely you'll get a chance to try everything you should have. And you'll spend hours going over should have, could have scenarios.

First thing we've committed to is a no tolerance preflight policy. Prop Rotations reconfirmed, Prop Tightness reconfirmed, Batteries secured tightly and Battery Connections secured with electrical tape and no dangling balance connectors. Point the bird into the Wind. When the bird is powered up all motors start together or restart. Since we're DJi NAZA/Wook - Wait for full GPS lock and Home Point Record (takes longer than we expect and like to wait). We then rerecord the Home Point manually. Upon liftoff, check control surfaces and gimbal controls work correctly, check Atti, Gps, then Manual. Flip back to Atti go fly.

What I'm NOW chanting in my head (and will say out load before every flight is) so that I can make it habit...

In the event of any failure - Raise radio and point RC Ant straight up - flip high HiPower on UHF- Atti to GPS to Manual, to full throttle, to IOC Home, to Fail. If I cant catch it at that point at least i'll feel like I gave it a fighting shot.

On this last one - I only made it to Full throttle. Dont think IOC or Fail would have helped but now will never know. Again, Pilot Error :dejection:

Anyways, thanks for the help all!!!
 

D

DennyR

Active Member
Sorry to hear this, I would go out and buy a Autoquad-6 and six dedicated ESC's and start again with a Tarot Hexa from Foxtech FPV. Repairing badly damaged stuff never lets you have confidence again. While you're there check out the new gimbal from Mastor.

Dealing with Qing Fu (Foxtech) and also Iflight is how dealers in China should operate
They have a great range of MRs to choose from
 
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SMP

SMP

Member
Good idea Denny! Just bought a pair of Foxtech Monitors (which are performing well above expectation) and shipping was incredibly fast. This ones for FPV but will take a closer look!!
 

kloner

kloner

Aerial DP
dam dude, you fubard that one good. i'd suggest that prop adapter wasn't up to the task...............
 

D

Dewster

Member
Use Nylock nuts. Go to a hardware store like Lowes or Home Depot. You can find metric sized nuts with a nylon/plastic insert. They will keep the vibration and rotation of your props from loosening your nuts. They really work well!
 

SMP

SMP

Member
Chuckling.... aye nose in, full speed. The impact Sound it made was pretty impressive.:black_eyed:
 

kloner

kloner

Aerial DP
sorry bro, i'll do another on the house if it helps...... you really needed them lil buggers. how long does hobyking orders take to get to you? does it go straight in or hit that freight broker on the way?
 

SMP

SMP

Member
Heya Mate, thats a super generous offer but you built it perfectly, flew awesome and you warned me straight up about those pinch nuts! Ordered em right after we talked so between HK to USA to Middle East still not here...what was that, a month +?? Just one of those breaks :) We'll see what happens with the TBS stock on the 7th. We've got a gig in Brazil July 4-22 was hoping to be able to rip him about in our free time. If the timeframes get too close I might overnight you some parts and catch it from you on the way through. No way we're doing it for free though ;) ;) You're worth every penny!! Thx mate!!

Moral of the story?? Listen to what your Builder tells you. Overnight **** that matters ;)
 


SMP

SMP

Member
I've been lurking you on your success w the RCTimer little brushless you've got Ken. They say imitation is the sincerest form of flattery; benched the musky/Martinez combo, got the Alex original in the mail the other day and pulled the trigger on the RCT gimbal a couple days ago. ;) ;)
 

R

RTRyder

Merlin of Multirotors
SMP said:
I've been lurking you on your success w the RCTimer little brushless you've got Ken. They say imitation is the sincerest form of flattery; benched the musky/Martinez combo, got the Alex original in the mail the other day and pulled the trigger on the RCT gimbal a couple days ago. ;) ;)
Click to expand...

I'm also trying to get a YUN-1 to work right with much less success. So far I've added a couple standoffs between the support arm sides to stiffen it, removed the inadequate rubber ball dampers and replaced with the same solid rubber isolators I'm using on the RCT, and flipped the roll motor around after changing it to longer shaft and machining an adaptor to mount the cradle to the shaft rather than the backend of the motor. After all that it's noticeably better than it was out of the box but still not up to the level of the RCT. The last remaining weak point is the motors which simply aren't strong enough to do the job, close on tilt but definitely too weak on roll. Rather than waste anymore time or $ on the YUN I'll probably machine a mount to put it on the front of one of my Discovery or the QAV500 where the jittery roll won't be so much of an issue.

Currently waiting for the postman to deliver RCT gimbal #2 to take the place of the YUN-1...

Ken

P.S. did I mention the Mastor GoPro gimbal is a ripoff copy of the YUN-1 with a hacked copy of Alexmos firmware...
 
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D

DennyR

Active Member
Thanks for the heads up on that Ken. I always build my own but it did look promising for the guys who want to fly it as soon as they get it.
 

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