https://youtu.be/YdDZlgDjYH8

This was after about 4 or 5 nice lift offs and some gentle hovering in the backyard.

The first few hovers were perfect, couldn't have been happier with the results.

Then my wife came outside and asked to see the heli hover and this is what happened.

Not sure why, any ideas?

Now I'm nervous to lift off again after I make repairs!

That is very sad.

Unfortunately the most probable cause was that swashplate was not level during lift off.

This can happen when motor is running and pilot will move with sticks.
Then swashplate will remain in deflected position and when lifted off, it could tip over because model want to reach desired position.

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Spirit System developer

Yup, sad to see.. The ground you're taking off from isn't the best, the spirit may have been trying to correct a tilt but the skids may have caught on something?? A good clean liftoff avoids that

Also please make sure that compensation directions are still working properly.

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Spirit System developer

Yes, it was very sad!

Thanks for the feedback. Compensations were were perfectly but will certainly double check on my next flight.

Will lift off in coxial or stabi help to reduce a tip over? I'm pretty sure I was in coaxial mode when I was lifting off in the video.

In Coaxial mode this should never happen. So yes, it should reduce tip over.
But we recommend to use this mode only if you are confident them model is all OK.
Because if not, this could be result of excess vibration.
In normal flying mode such thing will not happen even if there are excess vibrations.

So I recommend to just verify that swashplate is really level before lift off - do not move with stick before take off. And all should be OK.

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Spirit System developer

Ok thank you. Last question regarding coaxial mode. Will increasing ppm value on the coaxial switch act like increasing a coaxial gain or is coaxial simply on or off state?

Only ON/Off. Anyway I recommend to first tune helicopter for normal flight mode. Only when everything is OK, then try a different modes.

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Spirit System developer

My first maiden lift off and subsequent hovers were so smooth I could have done a no hands hover. I also quickly looked at the vibration reading [FUEL] and saw 20% which seemed pretty good. Coaxial mode was also engaged the whole time.

I think I've narrowed it down to either an upper linkage that split open (it was brand new) or an issue with the rotor blade tightness. The root of the blades and the blade grips were covered in a very thin oil which I think is from a new thrust bearing grease I was using.

Thanks for the feedback Ben. So you can take off in coaxial mode or did you have to let it spool up first then turn it on? Sounds like that mode gives you are pretty good locked in flight, Thanks