Needing guidence.

[omerco]

Originally Posted by A VIKING

You guys are awesome.

So were you changing your gain on the Tx or the Gui?

[A VIKING]

Originally Posted by omerco

So were you changing your gain on the Tx or the Gui?

In my case I am only adjusting a locked tail gain at the GUI and not the TX.
Is this correct?
Can you use both?
Should it be one or the other?
The gear switch on my DX7s was originally assigned to tail gain for the BX but now it is assigned to the banks (one set for bail out) so that's why I am using locked gain at the GUI, to free up the gear switch.
Thanks Omerco!

[omerco]

Yes that is OK.
u can use both just not at the same time :lol. doesn't matter. whatever is more comfortable to you (I use Tx and then i have 2 banks with different gains).

[omerco]

Originally Posted by jchen

Ģuys

sorry silly question. Ìf Ìf lock the tail gain in the gui, tx gyro gain will have no effect
on the tail gain, is this correct ? Ìm also have the same issue though tail is
holding, I'm having to run my tx gain at 90%. Ñot sure what Ìm doing wrong. Tx is
a jeti

thks

Yes it is correct. Post both tail tabs here so we can have a look if you are considered with it.
How is your tail behaviour? and what is the flight style you fly while checking it?

[A VIKING]

Originally Posted by omerco

Yes that is OK.
u can use both just not at the same time :lol. doesn't matter. whatever is more comfortable to you (I use Tx and then i have 2 banks with different gains).

So should I continue to increase the tail gain from 80% in hopes of eventually seeing a wag to tell me it's working?
I really haven't seen any change in tail performance from my starting point of 40% to my stopping point of 80%.
If you think I should try a higher gain, what should my stopping point be and if I increase my gain to the suggested high point, should I go the other direction, lowering the gain into rate mode to see if the ship responds in an effort to make sure the gain adjustment is being recognized?
I have posed this question to Georgi as well.
What do you guys think?

[omerco]

I think it is worth trying. there shouldn't be any problem going higher until you see side effects (wag for example). your described BeastX gain is also higher then the values I'm familiar with (27-30 +-)

The real gain in skookum is not the one you dial (total). if you want to see it go to top menu: View-->Display flight gain matrix (while connected to the gyro) and look mainly at the Hold gain. this will show more familiar values, although still different then other FBL

by the way how are your tail start/stops in both directions? did you check those?

Still didn't say what is the size of your tail blades...I can check with others i know what they use.

[omerco]

What is your gyro version by the way? are your running latest? or at least 3.4?

[A VIKING]

Originally Posted by omerco

I think it is worth trying. there shouldn't be any problem going higher until you see side effects (wag for example). your described BeastX gain is also higher then the values I'm familiar with (27-30 +-)

The real gain in skookum is not the one you dial (total). if you want to see it go to top menu: View-->Display flight gain matrix (while connected to the gyro) and look mainly at the Hold gain. this will show more familiar values, although still different then other FBL

by the way how are your tail start/stops in both directions? did you check those?

Still didn't say what is the size of your tail blades...I can check with others i know what they use.

Checked the flight gain matrix and found at my starting fixed gain setting of 40% in the GUI I have:
Rate: 34%
Hold: 27%
Accel: 0%

With 80% fixed gain set in the GUI I see the following in the matrix:
Rate: 60%
Hold: 48%
Accel: 1%

Stops are set just inside of contact.

Tail blades are stock 115mm.

Gyro version is 3.4

[A VIKING]

Looking at those gain settings in the matrix, that may be my problem.
At 80% fixed I have 48% hold gain, not that much really.
I'll keep pushing it up and see what happens, it might fix it.

[omerco]

Great. report back.

48 is high on skookum but for some reason your heli needs it...

Not sure it will solve your drift though...but lets see!

[omerco]

I have another thought i wanted to ask you about:

You said you are flying from the garage - arming inside and then going out.

What is the temperature difference between where the heli sits most of the time and the outside? temp change can cause drift!

[georgi UK]

=] I am starting to wonder about the RF side of things now? ie, rebind the sats, and/or bind in DSM2 mode? and/or start a new Tx model from scratch? one of those may do it?

[A VIKING]

My flight setup actually starts from inside the house, then the garage for power up and bind, then directly outdoors. Admittedly the ship is warm initially but at 20 degrees it cools off rapidly. I will try to let the ship and TX cool to ambient temps before flight for troubleshooting the slow left yaw.

I'll try a rebind also.

My memory is telling me I had no left yaw when flying SL mode. I believe the yaw started when flying in SL off for flight trimming.
On my next flight I will transition back into SL and see if this is correct. If it does stop the yaw that my give us more information as to why.

This next flight will begin with a lock tail gain set to 85%. That will give me a flight gain of 51%.
If making the transition from "SL Off "to "SL ON" does not make any difference in the slow left yaw I will increase lock tail gain to 90% and try again to see if I can generate a wag or stop the yaw. I will continue this process until I reach the max allowable 100% lock tail gain adjustment which will give me 60% flight gain.
I have my rotor RPM's set to a low speed just in case, don't want a lot of rotor energy if things go badly in the tests. The yaw happens at any rotor speed so the low rotor RPM will still show any changes.

Now if it would just stop raining!

Couple more questions/observations about the 720.
I notice that when I go to TH after landing the tail blades will shortly there after during spool down go to full left turn pitch angle and stay there until the rpm bleeds down, then the tail blades slowly goes to "0" pitch. Is this normal??

Also, on my last flight a few days ago before weather grounded me the ship landed with a flashing red light, not a flashing red/green (meaning high vibration) light but a flashing red light. which per the manual is indicating an "Error State", it does not mention high vibration with the flashing red light. What could the error state be? What is the 720 looking at to create that red flashing light? I started the flight with a green light and ended the flight with the red flashing light. Is this dangerous to flight? If it happens again what shall I do?

Thanks for helping out and looking into this, if it will stop raining, I can get another flight in with the above tests and will report back with the findings.

[omerco]

Originally Posted by A VIKING

My flight setup actually starts from inside the house, then the garage for power up and bind, then directly outdoors. Admittedly the ship is warm initially but at 20 degrees it cools off rapidly. I will try to let the ship and TX cool to ambient temps before flight for troubleshooting the slow left yaw.

You should let it cool outside. the fast change in temp is a good reason for a drift.

I'll try a rebind also.

No harm in that...

My memory is telling me I had no left yaw when flying SL mode. I believe the yaw started when flying in SL off for flight trimming.
On my next flight I will transition back into SL and see if this is correct. If it does stop the yaw that my give us more information as to why.

Very interesting...might indicate there is some Tx issue - maybe again from temp change!

I have my rotor RPM's set to a low speed just in case, don't want a lot of rotor energy if things go badly in the tests. The yaw happens at any rotor speed so the low rotor RPM will still show any changes.

That is not a good test - lowering RPM is the same as lowering the gain. you must set a gain per RPM. just prepare your SL bank with lower gain to bailout if needed.

Couple more questions/observations about the 720.
I notice that when I go to TH after landing the tail blades will shortly there after during spool down go to full left turn pitch angle and stay there until the rpm bleeds down, then the tail blades slowly goes to "0" pitch. Is this normal??

It is if the unit is again trying to yaw to the left and cannot because the skids are on the ground. it sounds like different version of the same problem. Georgi can see that in the logs i guess??

Also, on my last flight a few days ago before weather grounded me the ship landed with a flashing red light, not a flashing red/green (meaning high vibration) light but a flashing red light. which per the manual is indicating an "Error State"

When this happens you should leave the bird ON and connect it to the PC - you will see the error message on the screen in a new box (mid right side). we might be dealing with a faulty unit after all?

[A VIKING]

Just to be clear, I am not running RPM's lower, just staying with ST1 which is 1500 RPM. I explained that poorly.

Waiting on the rain, can't wait to try it out.

[A VIKING]

OK, so here are the findings from 4 test flights starting at a locked tail gain of 85%.

85%-still very, very slow piros to the left both in SL off and SL on.
90%-no change.
95%-no change.
100%-no change and that is the top of available locked tail gain in the GUI.

These flights were done after a rebind with the TX, all sat lights bright and steady.
Allowed the SK720 and TX to acclimate to OAT.
Absolutely smooth tail control operation under load.

At the completion of each flight the tail would travel hard over trying to continue the turn to the left until a slow rotational rotor RPM caused the 720 to reset the tail to "0" pitch.

I've included a screen shot and a couple log files for anyone interested in taking a look.
Because the ship flew so well without any of these issues before the Skookum change I can't get myself to believe it's a tail servo, ESC or TX issue. If I fly my old unit and these issues disappear that would prove that out I would think.

Maybe my unit needs a doctors visit, if that's the case, I don't hold a dark mark against the unit as I seen this happen all to often in the full scale world. These things happen and that's not to say I still may be overlooking something.

Still looking very much forward to flying the 720, still looking for that smoking gun to identify the issue.

Ideas?

[Luvmyhelis]

Geez bro. Out of all the people that this would be happening to? Honestly you should be seeing severe tail wag at these levels. I even went back and checked your servo setup numbers to make sure they were correct. I have quietly watched this thread, and all the advice is solid. We haven't talked about the Gov issues that can effect tail wag or drift. But the issue here is well outside that and not even worth mentioning at these numbers.

I would try one other thing? Unlock the gui gain figures and run these in your tx? It is worth a try but I doubt you will see anything different. It is just trying the one rabbit trail you haven't yet.

Personally I would put your old Fbl system back on just to double check and see if the tail still runs right or not after this. If it does, send the 720 in for an inspection?

[georgi UK]

=] each thing we do is a step closer to nailing it! could well be the gyro is shot? can you apply moderate force to the tail servo arm while powered up to check it's holding?

also shake the tail side to side quickly (in your hands!) to observe the gyro gain, is it equal both ways and more aggressive at higher gains?

I suppose the biggest clue here is the high gain does nothing.......

[A VIKING]

Originally Posted by georgi UK

=] each thing we do is a step closer to nailing it! could well be the gyro is shot? can you apply moderate force to the tail servo arm while powered up to check it's holding?

also shake the tail side to side quickly (in your hands!) to observe the gyro gain, is it equal both ways and more aggressive at higher gains?

I suppose the biggest clue here is the high gain does nothing.......

Excellent troubleshooting checks Georgi!

Powers up and checked the tail blade holding power at varying pressure on the blades all the way to stalling the servo and it holds without any forgiveness or kickback, perfectly smooth in it's travels under stress.

The good news from the gyro is it does respond to gain.
I started at "0" locked gain and the gyro does drop into "Rate" mode.
I increased the locked gain in 10% adjustments and powered up to check tail response.
At 10% locked gain I did see some small response of tail pitch change to fuselage yaw.
As I went up in locked gain I noticed that 40% was about the same amount of pitch change reaction to yaw that I would have seen in the BX.As I increased further this is what I observed.
In swinging the tail back and forth I picked up on how much distance the tail went in yaw motion before reaching maximum tail pitch change in both directions.
From this observation I could see that the tail required les and less of a swing in yaw to get maximum tail blade pitch change as I increased locked tail gain.
At 100% locked tail gain I could measure half the distance traveled of the tail boom before maximum tail blade pitch change occurred compared to the distance the tail boom traveled at 50% locked tail gain.
Very cool.
So the gyro does see and respond to the locked tail gain adjustments but it does not cause a wag at settings that would normally be way outside normal parameters.
The bad news is it doesn't hold a heading.

So now what....keep it coming Georgi!
Keep thinking, I will be your eyes, you can be my brain.

[georgi UK]

=] progress! no one has yet mentioned if the unit is absolutely square to the boom, that would be too easy and only covers the drift side of things, would you say the tail does feel locked at some point in the gain increases?