RC_MAN

My Feedback: (11)

One more question
on my thrust vectoring jet I was going to hook up a Y harness to the elevator output from the gyro. One end for the elevator and the other to the thrust vectoring servo. Can this be done?

DrScoles

My Feedback: (18)

Only if you want thrust vector on all the time… usually you don't.

jetspud

Couple of questions,

My 1/6 F-16 was crazy sensitive on the elevators during landing, before I could change settings, throws, and c of g if needed I ran our of gas and kind of messed it up. In the repair phase now.. Would this gyro correct it from being so sensitive even if I flew it as I did before the repairs. Basically could I have flown saw how sensitive it was on landing then put this gyro in fly again and see a great difference on landing??? I was in the process of decreasing the throws on the elevators between the flights to correct the sensitivity.

Second to maybe better understand how the gyro works.. You know how the majority of F-18F's would jump off the runway on take off and you having to nose it back down.. would this gyro correct this so that the take off would be a smooth one..


Thanks

David

FenderBean

is there any chance of having the gain to high so at faster speeds it starts to flutter? Something
i have experienced with r/c helis. Seems like with such a vast speed range you could have the gain set to on the border and at high speeds it could cause a flutter. I was just pondering today and this popped in my head.

George

My Feedback: (57)

The short answer, yes!

The longer answer:
On my Shockwave, if I did not allow the speed to pick up by keeping it "in close", everything was fine, but as soon as I took it out and made a long high-speed pass, the plane would begin to wag its wings just about the time it reached me. It took a couple flights to confirm this, but it was definitely happening every time it gathered enough speed. A quick adjustment with the PC to reduce only the aileron gain on one banks has solved the problem.

FenderBean

Thanks George, I just wanted to make sure I was thinking correctly. I really like the gps feature of another gyro for this reason, but like you said should be easy to tweak. Good stuff, Thanks!

Springbok Flyer

Hi Wayne,

Thank you for the confirmation. I have set bank1 with the default gain on the Cortex and my TX end point at 30%. When I check on the diagnostic PC screen it shows gain at around 25%. On bank2 I have again set up with the default gain on the Cortex but my TX end point at 35%. When I check on the diagnostic PC screen this shows at around 30%.

Do you think this is too much - given the fact that I cannot reduce my Tx end points below 30%.

Thanks for your help.

Jan

Bob_B

My Feedback: (11)

Jan if you use a slider instead of the switch you gain will be infinitely controllable. You can do the same with the gyro function with more options

siclick33

Jan,

Are you sure you can't reduce your end points below 30%? My old Futaba set has 2 ways to set the limit (called ATV and AFR). I think the newer radios also have this with different names (Travel and Limit?). I'm pretty sure you should be able to reduce the gain further using your transmitter.

Having said that, the values that you have don't look too bad but it is obviously airframe specific so noone will really be able to answer that with absolute guarantee until you've tried it.

Springbok Flyer

Bob,

I realise that, but the center position, which is the OFF position can easily get bumped. And that concerns me. Then again I suppose that I only need to use it for the initial flights until I have a handle on what is working for me on my model. Just my first venture into gyro's on my jets after 20 years of flying them without - so I am being very cautious and want to be sure I can switch the gyro off. I guess using a slider will also be better if I need to reduce gain because of oscillations during flight. The centre position is actually the smallest % gain......so if I bump it a little, it should only allow a small amount of gain.......

Thanks,

Jan

Springbok Flyer

Absolutely certain....but as Bob suggested, when using a slider or rotary knob, the adjustment becomes infinite - so my setup is only because I am using a switch....will reconsider the slider or rotary knob option...

Cheers.

siclick33

I'm not sure if I am barking up the wrong tree but this is from the manual:

[QUOTE] The Travel rate(normal full stick movement at high rates) can be varied from 30% to 140% in each direction on channels 1 to 16. Also, the Limit point (how far the servo travels when a mix is involved) where servo throw stops may be varied from 0% to 155% [/QUOTE]

I was under the impression that you could lower the rate to below 30% by lowering the Limit value. However, I still use an old 9Z and haven't used the 18MZ (or any of the 'newer' Futaba radios) so apologies if that's not correct.

Springbok Flyer

No worries, yes the limit is adjustable from 0%, but as the manual says, when a mixer is involved.

Cheers.

Bob_B

My Feedback: (11)

Yes I just did this setup with for a friend. Off/20%/40% very easy to do plus by simply switching form Normal to AVCS in the gyro menu you can switch from bank one to bank two and have totally different parameters and chose from rate mode or hold mold on any of the axis of control.

wfield0455

My Feedback: (7)

it acts as an absolute travel limit. Most often is used to allow full travel while preventing a mix from creating a binding situation. Still, servo won't move past that limit whether from a mix or stick movement. Connect a servo and try it...

wfield0455

My Feedback: (7)

i would get it down to 20% to start. I forget the exact details as I haven't flown Futaba for quite awhile but the absolute travel function will limit servo travel from any source, not just mixes..

Springbok Flyer

Bob,

AVCS - please explain? Also, how do you go OFF/20%/40% - I will only be able to go 20%/OFF/40% ?

Jan

Bob_B

My Feedback: (11)

First make a copy of your model to experiment with, then if you use the gyro menu, you can setup your switch of choice to be Off/On/On. Or On/On/On. Go into your gyro menu, assign a switch to the gyro function, on the 18 you will use three of the gyro functions, in the normal mode. Have your switch "off" at one side, "on" in the middle, and "on" on the other side. For each of the positions assign the gain value 0%, 20%, 40%. "normal" will put the gyro in bank one, "AVCS" will switch the Gyro to bank two. I use a 12fg and can post photos, the menu in the 18 looks different but is easier to setup. This weekend I can post photos of the 18 menus.

Springbok Flyer

Sorry Bob, but now I am even more confused. What gyro menu? The Cortex menu, or is there a gyro menu on the 18? Also what is AVCS?

Bob_B

My Feedback: (11)

Jan I'd suggest flying the model with your current setup. The gyro menu I'm referring is in your 18MZ. In the 18MZ gyro menu you have the ability to chose from "Normal and AVCS" this setting will tell your gyro which bank to use in simple terms.
Using the Cortex PC software allows one to customize each bank of the Cortex. I'll put together a tutorial on the 18MZ gyro menu this weekend.
I always suggest making a copy of your model in the TX and playing with the copy!
Bob

DrScoles

My Feedback: (18)

Spent more time troubleshooting this morning. I went through the set up, the rudder servo is making noise when it gets plugged in. None of the non-powered leads work. Including the gain channel. Someone suggested that the previous setup may have kept some things from working on the new plane. I have redone the set-up and still no bueno. I am positive I went through the set up properly, and positive I have everything plugged in correctly. No Y-leads, everything is directly connected. No boosters.

I know I need to hook it up to the software, just not looking forward to pulling it out of the plane to do so. I'm a mac guy, no pc laptop. Have to bring it to work.


Any suggestions???

wfield0455

My Feedback: (7)

Jan,

AVCS is basically "Futaba speak" for heading hold mode on their gyros.

F1 Rocket

Please send me an email with your contact info.
[email protected]

JimBrown

My Feedback: (2)

Here's a little tip that might help if you find yourself with a wildly oscillating plane. Throttle to idle and pull up to vertical. Once the speed has scrubbed off and the oscillations have stopped, fly the plane at slow speed while you calm your nerves. Then reach for the switch or knob to make whatever adjustment is needed.

I had got my Cortex nicely set up while at Georgia Jets. During the trip to Hamburg while at a campground, I messed with a mix in my TX and did not check it properly. On my first flight at Hamburg, I took off with the Cortex at 100% gain. While it made the take off roll very nice, during the first downwind leg as the jet picked up speed it started to oscillate violently. I immediately did the above and got the jet stable. I then moved the knob I was using to the middle, which should have turned off the Cortex. However, due to the bad mix, it only reduced it to 50%. I flew around slowly for a while then landed. Investigated and found the bad mix. Fixed it. Flew it. Found my high and low speed gains and moved it to a three position switch.

Happy camper here. Really like the way the Cortex smooths things out. One still needs to fly the plane, of course, but it is much more fun now. Will be getting more of them.

...jim

DrScoles

My Feedback: (18)

I flew my tomahawk viper with the cortex last weekend. Too cool. Not sure I have the gain high enough, but it smoothed things out dramatically. It would not knife edge without a slow roll. On the little plane I tried it on first, I could do knife edge circles all day long with just rudder and elev input. I was really concerned about the wings wagging, so probably not enough gain. Still really nice though. Ordered another one on the way home. :-)