Can position hold or RTL mode be used to rescue the heli if flying in Acro mode?

ArduCopter Traditional Helicopter
1

Hi all,
I have a question about Position hold or RTL mode.

Lets say ii am flying in Acro mode and somehow i loose my orientation and my heli gets inverted .Will switching to Position hold or RTL rescue my heli and bring it in straight position out of inverted position?
Thanks.

2

Yes, it should bring the aircraft back to a level orientation. Stabilize should work just as well. I don’t know if there would be any adverse responses with poshold and RTL as they will try to bring the ground speed to zero initially. Of course this all relies on the EKF solution remaining stable.

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Thanks Bill. Then i will program one switch on my transmitter to stabilize mode and will use it as a rescue switch.

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Instead of switching flight modes we use the Acro Trainer function, which can be switched in or out with a function switch from normal Acro to Trainer with self-leveling. This provides a very smooth transition back to wings-level if control is lost in normal Acro, very similar to the bailout function in FBL units. Although, unlike a FBL unit it will not provide a positive rate of climb for a bailout - you have to do that manually.

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Thanks Chris.I will check it out.

Sorry i didn’t understand by positive rate of climb.Does that mean if my heli got inverted in acro mode,then i need to bring collective down for climbing?

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No, with most FBL units if you use the bailout function it rights the helicopter and automatically puts it into a positive rate of climb so it don’t hit the ground.

ArduPilot does not do that. The Trainer mode with self-leveling will right it from an inverted condition. But you have to apply the collective yourself to prevent it from hitting the ground in the event you use that to recover from loss of control in normal acro.

I’m not sure how Stabilize works to recover from Acro loss of control. There is some slewing of the collective that takes place when switching flight modes, and I’ve never tried that. Leaving it in Acro and using the Trainer as a recovery mode does not change the collective curve, and that’s why we use it that way.

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Thanks.Will try acro trainer mode soon.