Slow drift to the left?!

[jskdog]

Just had a quick hover in the back garden with my 450 and the nose slowly drifts to the left, iv set the tail up and the gyro is an align rce 600. its running in heading hold mode. Any ideas?

[ddracer]

You need to set it mechanicly in rate mode first. Here is a sticky I wrote for another heli site. Hope it's of use. If you don't want to read it try lenghning the tail control rod one turn.

Forgive me if this has been done before but after reading a question on HLG200 giros I thought i would do a noob set up guide.

First make sure you have no slop in the tail rotor linkages and your belt if you have one is tensioned properly, as this will effect how well the gyro works. Check the direction that the tail moves compaired to the stick the leading edge of the tail blades will point the direction the tail is going to move, remember you fly the nose so it will be oppersite. NEVER USE THE RUDDER TRIM WITH A HEADING HOLD GYRO make sure the trim is in the middle then leave it alone. This is the reason you set up the gyro in rate mode mechanicly.

Two things you need to know:

RATE MODE.
This will stabalize the tail. If you get a gust of wind try to blow the heli round it will work to minimise the effect. If you fly forward and turn with cyclic (right stick for most of us) the heli the tail will follow the body.

Tip: in rate mode on the ground the tail will center it self when you move the rudder stick then let go.


HH or Heading Hold mode.
This will keep the heli pointing in the same direction you point it. If you fly forward and turn with cyclic the heli will move sideways, to get the tail to follow you will have to move the left stick.

Tip: In HH mode on the ground when you move the rudder stick the tail will move to one side and stay there. This is normal as it is trying to move the tail of the heli round at the rate you have told it but as its on the ground and not moving it just keeps trying.


Setting up the gyro.

First thing to do is set the direction on the gyro. This is sometimes called the reverse. This is a very different thing to the stick direction reverse on the transmitter. To check the gyro direction put the gyro in HH mode. Put the heli on the floor and turn it on, give it 5 to 10 seconds to initalise. Turn the heli clockwise 90 degrees the leading edge of the tail blade should move in the oppersite direction and stay there. if it points in the wrong direction set the reverse on the gyro.

If you have a gyro that will do rate and HH then set the mechanics in rate mode before setting up the heading hold side. Most people skip this step and wonder why they never get the best from their gyros. To set up the gyro make sure you have the gyro set in rate mode with low gain. eg. on JR/Spektrum set the gain to 49%. and set rudder EXPO to about 55%.

Be honest with youself here. If you are not a confident pilot then set the rate mode gain to about half its range (25% on a DX7 instead of 49%). I use no gain (49%) at all but you have to be "Jonny on the ball" with the rudder inputs when you first get off the deck.

Get all the linkages mechanicly set eg. 90 degrees you will notice the the tail blades have about 4 to 8 degree of pitch on them when this is done.

OK the fun bit. Hover the heli. This is best done with no wind. If there is wind make sure the heli is pointing into wind. The reason you set 55% EXPO on the rudder is because if you set the gain to 49% you are flying this old school the gyro will be doing nothing. If you don't add the EXPO you will really struggle to control it. If you have set the gain to 25% it will be alot eaiser.


If in the hover you have to hold some rudder in to stop it spinning then you need to adjust the lengh of the control rod until the heli will stay pointing into wind without you putting in any input with the rudder stick. It will move slightly as the wind direction changes.

Now take the EXPO out I find different people and different gyros feel better with different amounts of expo but I usuall run between 20 to 40% some people don't use any but I find when stick banging the pitch I end up putting unwanted rudder input in this minimises the effect. Right now start increaseing the rate mode gain. (20% I know thats a decrease but your gyro instructions will explain why) Fly it again feels better yes?

Keep uping the gain by 5% and testing until it starts to feel worse when you get to that point go back 1% at a time until you reach the point it feels good again.(Sweet Spot)

Rate mode is now done.

HH Setup.

OK read the manual for your gyro, Most gyros have End Point Adjustment (Do not confuse with End point/EPA on the transmitter, we will get to this later) if yours does not you will need to move the ball on the servo are closer or further away from the screw in the middle of the arm until you are getting as much movement as possible on the tail without the slide binding on the mechanics at each end of the tailrotor shaft.

If it does have computerised adjustment follow the instructions in the manual for setting it. Once this is done set the gain to about 70% and test fly. While hovering give the rudder stick some input then let go. What you are looking for is for the tail to stop dead if it wags then back the gain of 1% at a time until it stops if it does not wag then up the gain by 5% and test again. Do this until you get wag the start backing off 1% at a time until it goes.

Your basic setup is done.

Advanced setup.

Not going into this to much as all giros are different in how the advanced stuff works and is set up but the most common one is pirouette speed. This is where the EPA on the transmitter comes is. If you want a higher pirouette speed the you increase the EPA on the transmitter and vice-a-versa. In HH mode the speed of rotation is proporsional to the amount of stick you put in therefore increasing the EPA makes you spin faster. As the meircat says "SIMPLES!"

There you go sorry its long winded, and I know it sounds geeky but I love gyros and setting them up for people. Even people that think their gyro is ok are sometimes suprised at how much better they are with a good setup.

Please feel free to chime in if you think I should add something.

DD

[jskdog]

Thanks ddracer ill have a go at this tonight. Very detailed instructions!

[Trent]

Great post DD!

[ddracer]

Cheers guys. If anyone wants help then you only have to ask.

[sooren]

Now thats what I call an answer!
Regards
Paul