So I just finished setting up my X8 Octo to run on 5S and decided to do a full test flight. I flew for about 7 minutes, lost a prop and then the whole thing flipped.
Here is a link to the crash http://youtu.be/XCinEiDRB08
I could hear the X8 didn't sound right at the end of my flight so I was coming in to land when it happened. In the video you can see the prop fly away then a second later it decides to flip.
The pictures below show the damage after the crash. The top rear left prop was the one i lost in flight and I assume the bottom front right motor mount was broken during the crash but i could be wrong. I tried to take a look at the logs to see if it broke before or after the crash but I couldn't tell. Could someone take a look and see if they can get any info from the logs please?
Replies
Looking at the video, or more precisely listening to the sound, it is clear that you had a mechanical issue.
Glad you did little damage.
How can it be your motor mount got loose? How is it fixed?
I did not know you could fly 5S or even 6S batteries with these motors. If you can indeed manage to increase your voltage and prop size WITHOUT burning your motors, you will get better flight times.
What is your AUW on this X8?
The motor mount actual broke in half, it's fiber glass. I need to reinforce the motor mounts to make sure it doesn't happen again. I have been using this frame for a while and it was in a crash with the previous motors so it was probably comprised. I have a couple spare motor mounts so it was a fairly quick fix.
Over on rcgroups a guy has been running on both but i believe he is running 10" props. I wouldn't go 6S with my setup do to the weight of it. I put the setup into ecalc and everything stays within the limits, i can even do 12" props within the limits. After testing I checked the motors and they barely warm.
It's 2300g without battery so in that video it was aprox 3500g with 10A 5s and 11" props.
Hi,
To be honest I never could match ecalc simulations with my real measurements !
I think there is something that I miss or the tool just does not work most of the time. It is certain that ecalc does not proide reliable results for an X8 multicopter (it was made only for flat octo config).
Therefore I only use it to check if a ESC/BAttery/Motor config makes more or less sense, but then I do not look too much at the numbers it gives (it is more to check you do not pass the limits).
I noticed after watching my video a few times that it looses the prop seems fine for a split second then yaws then rolls and crashes. I would think if it was the prop that caused it to crash it would react right away and not be so delayed. Can anyone verify whether the timing is off or on for it to be caused a the prop loss?
I took a closer look at the motor with the prop mount that broke and i don't notice much physical damage that would have caused it to break. There's no damage to the prop either, not a scratch.