What have I done wrong?

[powelly999]

Thanks all for the advice and knowledge, I’m going to work through it again taking onboard all your pointers, maybe I was just too apprehensive on taking it off the ground. I’ve dug out my old training skid but it seemed a little unsteady so I suppose I may have been a little over cautious!
Just a daft question though, when you say it’ll react differently when in the air, how does it know when it is off the ground?

Regards
Andrew

[trillian]

Just a daft question though, when you say it’ll react differently when in the air, how does it know when it is off the ground?

Regards
Andrew

It doesn't actually know. But what it's looking for is movement when commanded and no movement when not commanded, so the motion sensors are always telling it if the heli is doing what the TX sticks have requested, or that it is remaining stationary against outside forces, rotor torque etc. when no command is given from the sticks.

[ian4655]

Tail issue.

On the ground it can’t compensate as there is drag on the skids etc. And it can’t compensate for anything.

Once in the air it sorts itself out and then the gyro knows where it is. Simple but that’s how I understand it.

Always get the tail rotor in line before you spool up. Another idea. When the beast initialises, if it is say pointing 60 degrees in a different direction to where you put it for take off, if there is no rudder input from the tx it can think that there is where it needs to point to be level, so it will attempt to correct to that orientation.

If it’s a few inches or the other stuff off the ground then the gyro should start correcting for torque and then compensating after inputs.

It is sort of counter intuitive but it works.

That said, don’t go throwing it 10 foot up to find that something is wrong.

Also, training undercarriage can cause vibration which tricks the fbl into acting like a mad thing, sometimes. I have experienced that myself.

Again, good luck for your next outing.

[waveydavey]

How much gyro gain have you got, IE what are your end point settings on the gain channel

[Grumpy]

As the others have said.. The gyro doesn't 'know' if the heli is in the air, but it does know if the heli is responding to control input. On the ground the heli cant respond normally so that effects the gyro.

To demonstrate this: Give the heli a input of right rudder, the pitch slider moves over (to the left) and stays there. Now take the heli and physically turn it to the right as if it were responding to the control input. The tail slider will move back to centre once the right turn commend is achieved.

[Mike Sanders]

I am no expert but I think that if the fbl unit sees an input it will react to it. In the air this will correct the attitude. On the ground the heli won't move in response to the fbl's command (because the ground is in the way) so it puts in more command and so on until the heli tips over. It doesn't take long!

[powelly999]

How much gyro gain have you got, IE what are your end point settings on the gain channel

The only alterations I’ve done are the beastx setup endpoints for the rudder, swashplate, and the pitch curve on the TX. The gain settings on the beast are all set at midpoint as they came.

Thanks
Andrew

[powelly999]

I think it’s just me thinking it’s going to react the same as my old shuttle with the gyro, I need to grow a pair and actually get it in the air. I sort of understand what it’s trying to do so I’ll give it another go tomorrow and see if it’ll work. Thanks everybody for your help and patience with a returning numpty!

Thanks
Andrew

[waveydavey]

The only alterations I’ve done are the beastx setup endpoints for the rudder, swashplate, and the pitch curve on the TX. The gain settings on the beast are all set at midpoint as they came.

Thanks
Andrew

Not sure that's right Andrew. The gain setting is set via channel 5 usually and you need to adjust it, it won't be set automatically.

[powelly999]

Not sure that's right Andrew. The gain setting is set via channel 5 usually and you need to adjust it, it won't be set automatically.

Oh! Best I go do some homework

Thanks
Andrew

[waveydavey]

Not sure how much a 450L needs but for a 600 on Spektrum radio gear around 40% was a good starting point. You can see via the led's when you plug in what mode it's in, HH or rate and you can also see how much gain is active.

Gyro gain and operation mode
The tail gyro gain is adjusted by one of the transmitter‘s auxiliary channels. The more servo throw this channel produces, the higher the tail gyro gain will be. Additionally, the direction of servo throw determines whether the gyro operates in Normal-Rate mode or in HeadingLock mode.

While adjusting the gain or after initialization sequence was finished, the current amount of gain is displayed by one of the menu LEDs for about 10 seconds: When the gain channel is centered, this will correspond to 0% gain indicated by LED A. The maximum adjustable tail gain is 100% and will correspond to LED N.

The color of the Status-LED indicates the selected mode: Purple indicates Normal-Rate mode and blue indicates HeadingLock mode.

N	M	L	K	J	I	H	G	F	E	D	C	B	A		B	C	D	E	F	G	H	I	J	K	L	M	N
100%	96%	88%	80%	72%	64%	56%	48%	40%	32%	24%	16%	8%	0%		8%	16%	24%	32%	40%	48%	56%	64%	72%	80%	88%	96%	100%
-100	-96	-88	-80	-72	-64	-56	-48	-40	-32	-24	-16	-8	0		8	16	24	32	40	48	56	64	72	80	88	96	100
Normal-Rate mode														HeadingLock mode

Please note that the actual percentage and sign of servo throw in the transmitter will depend on its brand and/or type! For the first flight we suggest to start with medium gain not higher than LED G (LED D for 450 size helicopters and smaller) in HeadingLock mode (Status LED blue).

[powelly999]

Well I’ve had a day of reading and reading, I can now understand where I was going wrong. I’d set the tail servo centre point while it was not in heading hold so when I came to do the endpoints it was way off. I was also getting confused with the using channel 5 for the gyro as I’ve got a single line reciever but I’ve been through it all several times now but still just as it starts to go light on the skids, the tail tries to spin around. I’ve set the Gyro gain to 50%, tired higher and lower but the same outcome. Slowly starting to loose the will here!

Thanks all for your help though, I’ve learnt a lot about it all in the last couple of days, just wish the literature for all the points to be sorted could be in one place so you don’t have to watch videos, look at quick reference guides, search the Wiki, and trouble you lot on here.
Thanks
Andrew

[StreetDragster]

How quickly does it start to piro?

If its fast, your gyro could be reversed. Easy way to check is to move the rudder with the stick and see which way the tail slider moves when you select left rudder.
Move the slider all the way to the right with right rudder, and then physically turn the helicopter nose right/clockwise, the tail slider should move to as you observed previously for a 'left rudder' command under gyro control.

Does it do this?

Maybe post some pictures of the tail setup, bellcranks, rudder servo etc. Maybe its something like the tail grips are the wrong way round or blades backwards or something. With a clockwise rotating rotor head, the tail should turn anticlockwise (assuming blades are on the right hand side of the boom) so that the tail blade moves 'upwards' towards the rotor disc.

Matt

[powelly999]

How quickly does it start to piro?

If its fast, your gyro could be reversed. Easy way to check is to move the rudder with the stick and see which way the tail slider moves when you select left rudder.
Move the slider all the way to the right with right rudder, and then physically turn the helicopter nose right/clockwise, the tail slider should move to as you observed previously for a 'left rudder' command under gyro control.

Does it do this?

Maybe post some pictures of the tail setup, bellcranks, rudder servo etc. Maybe its something like the tail grips are the wrong way round or blades backwards or something. With a clockwise rotating rotor head, the tail should turn anticlockwise (assuming blades are on the right hand side of the boom) so that the tail blade moves 'upwards' towards the rotor disc.

Matt

Thanks Matt, I’ve not got a lot of time over the next few days, but I’ll go through and check all the points you have raised and get back to you soon.

[Grumpy]

Move the slider all the way to the right with right rudder, and then physically turn the helicopter nose right/clockwise, the tail slider should move to as you observed previously for a 'left rudder' command under gyro control.

Just to avoid potential confusion: The pitch slider should move to the left with right rudder application. If it moves right then travel is reversed.


If in doubt a short video posted here would be a double check.