8th flight on my new Protos Max. 715 Clyclones, Black dampers, Spirt FBL. A friend who is a very good pilot was flying. He wanted to test the Spirit rescue mode. I've used it with no problems. The second time he hit the button the heli exploded. The devastation was instantaneous and complete. Truly a spectacular thing to watch.

Help me prevent this in the future.
I think I may know where I went wrong. On pervious helis (Align) I set the cyclic ring as high as possible without binding. On the Protos I was surprised how high I could set it. I thought that was a good thing. Now I think maybe it is too high. Also with Spirit I can choose how much collective is applied for rescue. More collective equals faster rescue. So I used 100%. Now I think maybe this is too high.

I'm still kind of new at this stuff so what do you smarter and more experienced people think?
How do I determine where to set cyclic ring and collective?

Oh, this is very sad
I recommend to set Cyclic Ring so that angle is not higher than Collective Pitch.
Generally it should be enough if your Cyclic angle is around +/-10°.
If 10° will be enough for you (rotation speed is not affected), then you do not have to increase it at all.

If all parameters are maxed, then probability of boom strike is increasing especially on the big helicopters. When your head speed is low then the chance is much higher.

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Spirit System developer

This is very sad indeed.
What’s really sad is that I set it up exactly like the manual says to do it.

Quote from manual page 41: “Now it is time to set the Ail/Ele maximum cyclic pitch range. Try to set the largest possible deflection. This parameter does not directly affect the speed of rotation, but if it is too low, the model may not have consistent pitch and roll rates.”

No mention of “Generally it should be enough if your Cyclic angle is around +/-10°.” Or “If all parameters are maxed, then probability of boom strike is increasing especially on the big helicopters.”

So I followed directions and destroyed a brand new Protos 700 because of it. Total loss, well over $1000. In the hole because I did what the manual says.

Oh man I can feel you..... I used to hit rescue (just to get the routine) on every flight and discovered also aggressive cyclic inputs, which lead to me to use only acro mode.
Means Heli stays inverted once inverted but always climbs out upwards. Goal to get away from ground.
With 60% Collective pitch I have good recovery with all my Head speeds from 1500-2400rpm.

This saved me at least 3-5 crashes, where I lost orientation near ground on exercising backwards inverted cycles.

I agree that manual should be more clear on impact, if Cyclic Ring is well above any usual Cyclic angle in terms of ESC Load and boom strike risk.

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Oxy4max SpiritPro + HW // SOXOS 550, SpiritPro, HW120A V4, 920KV // SOXOS 600, SpiritPro, HW160A, Pyro650 // SOXOS Strike7, SpiritPro, HW160A, Pyro750 // Skywing Spirit Aero // FrSky Horus X10S + Taranis X7 /

We will update the manual with more detailed info.
Unfortunately it is always needed to think about the model capabilities. There are Scale models that can get boom strike even with 6° and there are models that can fly even with 20° collective pitch.
Also it is possible to get boom strike even with small angles if the model is not configured properly - this can happen whenever there is blade stall and high torque. With bigger helicopters (600+) this risk is increased a lot.

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Spirit System developer