E7 Crash One Way Bearing fail in Flight ! Video

[Oliver Mauthe]

Hello

In my Last flight the One Way Bearing give up and I crasht my E7. Anyone else have Problems with the One Way ?
Motor Setup:
Jive 120 with Pyro 700 Black Edition

Here is the Video from the Crash

Thx Oli

[steffgiguere]

Wow  nice field by the way.

I have 268 flights on my E7 and we have many members with E6 and E7 and none has yet reported one way bearing failing.
 
Sorry to hear and see.

[Nigel Sawyer]

What was the clicking sound before it lost head speed? Sounded like some thing came loose?

Did the main gear or pinion strip? How bad was the damage to the over all model? Hard for me to tell what's going on for sure from watching and listening to the video.

Sucks that it went in. I have crashed lots of Heli's and know its tough when you get them working the way you like. You really had it moving out man.

So far I have not had any problems with my one way bearings on my Synergy's failing. Hope you get her back up again soon and keep up your great flying.

Nigel

[churchyj]

I have never seen a crash where a locked one way bearing casued the crash, you could keep flying the model with it locked up as long as you did not suffer any power loss.  On the vid, there is a sound that is different to any auto hub issues.

[Oliver Mauthe]

Hello

The One Way did Not locked, it spins now in Booth directions freely.
The Main gears are ok, when it lays on the ground the Motor Turn Free because the One Way spins freely

Oli

[Jean-Luc Bolduc]

First time I hear about free spinning OWB. Was it lubed ? 

I have 550 flights between E6 and E7 flying lots of tic tocs with no OWB failures.

[Kevin Dalrymple]

I have seen one in a Trex 700E. It happens. Sorry about the crash. Could you have autoed out of it?

[Matt Botos]

Oliver, I have never seen a OWB fail on the E7. However, I could imagine a few scenarios that may cause premature wear or stress on the transmission.

1. Incorrect ESC governor settings. - If the Governor gain is too high the motor will have a constant chatter which will act as a jack hammer on the transmission. I have seen a few models configured this way and have corrected the configuration before it caused any damage. The chattering is very violent, on any other helicopter the main gear would likely strip immediately.

2. Using grease on the one-way. - I have seen this cause problems with the one way on an N5c.... especially in the cold. The grease mixes with dirt and metal from the inner race and creates a very thick substance that can cause the pins to stick in the outer position. Use a light oil.

Let us know how you progress.

Thanks,

Matt

[Adam.Melton15]

Actually Matt, I hate to be the bearer of bad news but this happened to me last weekend at an exhibition flight. I took off and flipped it but lost all power and went straight into the deck. Fortunately I have had over 100 glitch free flights before that. Heli all repaired and will be testing this weekend.

[Oliver Mauthe]

Hello Matt

thx for reply
I am using a light oil for the owb, no grease. The gov is an jive 120 in Mode4 i using this setting for all my Heli`s.
I upload a Video where you can see the owb. I think the own is undersized for this Heli (E7)
my gears are all ok it is not stripped, you can see in the Video the owb faild in the 4side tic doc and you can hear the motor spinning when the Heli lies on ground.

Oli

[Oliver Mauthe]

Here is the Video

[Jean-Luc Bolduc]

I would not say the OWB is undersize for E7 application. It's very unusual for the OWB to freespin both ways. Replace bearing and check if the sleeve is not undersize by a few thous.

[Yanick Larouche]

Hi Olivier!

Put one new bearing.

Sometime inner race does not work well and the sleeve spin free inside the bearing.

Maybe it's your case !

The part number of this bearing is:   108-111.

When i install one new one way bearing i always clean the bearing with wd-40 for remove grease and i put light oil like scorpion oil!

Thank's !

Yan

[Matt Botos]

The one way clutch is properly sized for the application. This is the first I am hearing of any type of failure. I have seen one way clutches damaged (no failure) from oscillating ESCs.

Also, make sure you loctite the bronze bushings into the aluminum hub. They should not be allowed to float. The bronze bushings are critical to the centering of the inner sleeve. Without proper centering you could be setting yourself up for problems.

I watched the video, the sleeve definitely looks loose inside of the clutch but it's damaged so very hard to diagnose. Please measure the size of the inner sleeve.

Thanks,

Matt