Vibration and flight video of gasoline helicopter

Hello Chris,

I am just trying to verify what i understood from the five point throttle curve that in an autonomous flight with this new feature pixhaw doesn’t need a governor at all? or this funstion only works with RC input.

Thanks,
Tolga

The only thing it requires for RC input is an on/off switch on your throttle channel (normally 8). The software controls the throttle based on collective pitch loading. Yes, it works great in autonomous flight with no governor used, for both electric and combustion engine (requires different throttle curves). It mimics perfectly in software what the conventional throttle/pitch does in your RC with a heli without an autopilot.

But it is important to tune it correctly, just like it is when you fly with a FBL unit with a throttle curve in the RC. For combustion engines it is important to use full throttle at full collective pitch loading or you can’t use the full power available from the engine and it will bog out if you load it heavily. Bogging the engine down is a point of no return with a helicopter because if the engine bogs down, it loses headspeed, which loses lift and requires more pitch - until the pitch is maxed out, the blades stall and the heli no longer flies.

With your GX9 I would recommend installing telemetry on your RC for headspeed display on the radio screen so you know where you’re at for tuning. These helicopters are very vibration-prone due to the four-stroke engine, and they were designed to run at 1,160 rpm main rotor speed. Which provides the least amount of vibration and best engine power (6,500 rpm). As I stated earlier the engine is not exceedingly strong for this model, so having the throttle curve set to hold constant rpm is very important or it will vibrate like crazy. A tachometer is the only real way to know that.

Hi, Chris.
I have a really strange situation today.
As you can see in the image, Arming and starting the engine will start the engine well.
However, disarming does not turn off the engine because the engine must be turned off.
This case is very confusing for the first time.
I did not have this phenomenon in the past, but I do not know what went wrong.
As you can see in the picture, the carburator must be closed by hand before the start is turned off.
I will upload my parameters as well.
Please advise what is wrong.
I’m always thankful.

(Video)
https://drive.google.com/open?id=1Qc-VMsW0vPJJfUv3qlgIGdmttj-UH9ZI

(Parameter)
https://drive.google.com/open?id=1r8alVrehpzBxq-2Br-9dtJvqKh22B1R7

Yes, it appears to be getting air thru the carb yet with the throttle all the way closed. Verify that the idle speed screw is backed all the way out so the throttle plate fully closes, and that the throttle servo setting also moves it all the way closed when disarmed.

I would also set the SERVO8_TRIM to the value that corresponds to the throttle closed.
SERVO8_FUNCTION,31
SERVO8_MAX,2020
SERVO8_MIN,1300
SERVO8_REVERSED,1
SERVO8_TRIM,1500

On all gas helicopters I use an ignition relay, as well, that grounds the ignition primary to the engine case to stop the engine if the throttle servo fails or binds. I set up the ignition switch on a separate channel (usually 8 is throttle hold, 9 is governor, 10 is ignition). Without the ignition switch there is no way to stop a runaway piston engine, as they are totally self-sustaining independent of the armed state of the flight control system if the throttle fails to close.