Stabilization

Happy new year...

It's not only nose-in or turning inside, it's scale flight at its best with the scale helicopter in all of it's full scale brother attitudes. It's quite easy with practice on standard tail helis (raised or straight) which have much better tail authority. Last summer I flew my new 1/6 Vario H145 which is a modified EC-145 with a Vario 10 blade fenestron. The new fenestron is lighter and a lot more efficient than the old 8 blade or 9 blade Roban. And easily adaptable since it has the same form factor as Align. But I dont use either and against all detractors mine flies perfectly with a belt drive. The new fenestron does not bring tail authority to levels attainable with standard tail blades but provides enough for most circumstances. Although it's still a light wind flier. So far I have built 4 fenestron scale, two H130, one H145 and the latest one a 600 size Gazelle (with the old 8 blade and CW blades), I will complete setup this year. I intend to build a 3rd H130 with the 10 blade Vario for this summer also.

https://youtu.be/mJ8nn5DdGQs?si=t0U6CKuQK_DpS-sf
https://youtu.be/zPySNsuKMVg?si=1RCE34gi1EM3aEpd
https://youtu.be/qx-QkmtXhxI?si=nG3i9noape3gaevX
https://youtu.be/Uiz6wcz_BCA?si=C6CWJOwLu5P8Kg9A

This very much outlines last season...

For 2026, I have the Vario 520n on the work bench. I ordered a 1/4.5 R22 from my friend at RVE, I should get in a few days and, will build a 5th H130. All to explore and improve orientation flight for scale.

Have great new flying season and remember if they stay on the shelf, your skills are not improving.

I was lazy today and was almost too embarrassed to post this, but I concluded that my cautionary tale was more important to share than protecting my ego.

Last week, I took the 1/4 Lama out for a maiden since purchasing it from Gonzalo and rebuilding the mechanics and fuel system. On spool-up, the blades were not tracking well so I shut it down and went home. I replaced the head rods with turnbuckles and re-tracked it. I mention this because I could have tried to do these things at the field, but I know better.

Yesterday, I brought the Lama out for a second try. I spooled up and before I even reached mid-stick, she gracefully floated into the air. I actually exclaimed out loud that this machine was the smoothest I had ever flown (it seemed that way). I hovered and performed some initial flight maneuvers and was absolutely blown away by how it flew. I did notice that it had a slight backward drift in a hover and was slightly sensitive so I decided, after 3 minutes, to land and adjust the expo in the radio.

I landed, spooled down and adjusted the expo. I then went into the AXON menu on the transmitter and examined the agility settings; they looked fine for the bank I was flying in, but I could not find a way to trim the elevator from the transmitter. THIS IS WHERE I FAILED MYSELF.

Rather than shut down for the day or pull the deck and connect a cable to the AXON to adjust the cyclic trim, I told the guys around me that I was going to "cheat" and put in 3 beeps of forward cyclic trim. I was well aware of the rule that all trims should be at 0 but I had cheated in the past (likely with a 3X or 401 on the tail) so something in my head told me I could get away with it.

NOT THE CASE. Thanks to input from Gonzalo (full scale pilot), Danny Melnik, Tommy Dean, and Mark Smith, all of whom sent me to the internet to research ground resonance, I now understand why my lazy move was almost guaranteed to cause the mishap I experienced.

HERE IS THE LOWDOWN:

The AXON interprets trim commands as inputs. As such, the AXON sees the radio's trim as a constant, intentional cyclic input. While in the air, the AXON can correct for this. But, on the ground, the skids create a mechanical connection between the machine and the ground. As the rotor nears full speed during spool up, the persistent cyclic input can accentuate the natural frequency of the blades' lead-lag motion. This can cause them to move out of phase, shifting the rotor's center of gravity away from the axis of rotation. As the unbalanced rotor turns, the helicopter rocks on the skids (you can see this in the video). Once the frequency of rocking matches the blade frequency, you get resonance, which is SELF-AMPLIFYING.

THE LESSON: I can fix the damage to the model. I was able to shut down the system fast enough to mitigate the resonance and prevent a rollover. But there was no reason I had to experience this other than LAZINESS. I should have addressed the issue properly but in my desire to fly again, I overlooked an obvious rule of operating these machines.

I am sure many of you already know this rule (as I did). Yet, it didn't stop me from doing a stupid thing. I hope my experience graphically illustrates why -- especially with larger machines -- we should take nothing for granted and ALWAYS take the hard path of patience and deliberation before we fly.

I posted additional insights in the comments. This issue is one experienced by both full scale and model pilots. In the full scale world, instructors will most often NOT induce resonance for the student, but rather ask the student to observe what the instructor does in order to understand how to respond. I can say that having this experience has CEMENTED the learning in my brain.

Find ideas of things to check if your heli doesn't stay super tight on horizontal axis when hovering, typically circular moving around axis. Can happen since day one or slow degradation.

1) Check the shaft of all swashplate servos: excessive play can result to lack of precision. Compare the servos, they must be identical. Check also when new.

2) No excessive play of ball links, consider experiencing another brand, some are more tight while still smooth, thanks to high grade polymer.

3) Consider replacing bearings if lot of hours
of run. Some can feel difference after major overhaul. See all exchanged parts in picture, more than strictly necessary but since on it..

I picked up a Jeti DS-16 and a number of receivers and have managed to get everything working just fine on one of my 3D Heli's using the Ext serial port from an R3/RSW to my Ikon2, and all functions work just fine (I have owned a Jeti in the past but only flew 3D Pod and Boom, so that part wasn't too difficult). Scale Heli's may require more outputs but how do I access the spare ports on, for example a Rex 7 or Central Box while at the same time using serial EX-Bus.

Now, if I was using a Rex 7 or Central Box would I be able to use the spare ports on the RX to handle additional functions such as lights, extra servos for retractable search light etc. and how would I accomplish that?

Google isn't much help here.

Perhaps the only way is to set it up as a standard RX with a loom to the FBL.

Any suggestions would be appreciated.

I am setting up a 3X unit and was wondering if there is an option to remove the servo connection from the 3X unit and have the gyro work in a serial output mode. some of these digital servos are power hungry and the central box is made to deal with that.(bavarian demon even makes a big deal about this by requiring dual power leads with jeti in serial-in mode) but if there is no option to leave the servos plugged into the central box (or receiver for that matter) what is the point of having the central box or the bigger power management RX's? it seems that the fixed wing version of the gyro has that option explained in the manual, but I see no reference in the heli-version manuals. there seems to be a black hole in data on the internet for this information. am i stuck just using the servo outputs in this unit?

First post on this forum. Haven’t flown Heli’s for over 10yrs. Decided to get into the scale game. Picked up a Roban 800 MD500D Magnum PI edition.
I am really enjoying my build and getting acquainted with heli setups again. I have been flying on the sim 2-3 times a week and it’s like riding a bike. It all comes back in a few sessions.
So far I am almost complete with the scale build side of things. Just need to mount the load line hook and a few other minor details.
At the moment…. I have built a test airframe and I am setting up the Demon 3x.
I have been taking my time with this one as I am kind of ocd. Lol Did full carpet and headliner in the interior. Had a co worker work some magic on GI Jane. Who we now call GI Dane lol. I can’t say enough about Tyler Gray Models scale detailed parts for the MD. Really sets it off and functionality at getting to electronics.

Here are some build pics.

I’ve used a few different flybarless systems over the years and some have been better than others. What I have discovered is that a pilot is looking for a “feel” and “connection “ to the helicopter. Each manufacturer has their unique methods to achieve this “connection “ and some are better than others. My choice is The Bavarian Demon which was developed for both 3D and scale applications. My point: when you find the FBL system that works for you, stick with it because it’s the best FBL system that works for YOU. Here’s an older video with with a test flight after setting up the Demon 3SX. Helicopter is 8ft long 1100mm metal blades and 46lbs. It was upgraded to the Demon Axon for the Jeti telemetry features prior to sale.

Hey Guys, you might run into this issue like I did with my Baby Lama. I'm running:
- Kontronik Pyro motor
- Kontronik Kolibri 90 LV
- Bavarian Demon 3X
- Jeti REX7 receiver

As you can see in the video, immediately after spool up (slow 60-second spool), servos would twitch. This happened in my first hover tests as well. Here's what I did to track down the issue (with lots of advice from my friends):

- Checked whether there was an inadvertent short in the motor by putting an ohm meter on the housing of the motor and each lead from the motor. This can happen if one or more mounting bolts touches the motor wires. NO SHORT.

- Made sure I had a ferrite noise suppressor on the cable running from the ESC to the receiver.

- Moved the ESC out of the fuse to see if proximity was the issue

- Finally decided that the noise was coming through the power lead of the ESC directly into the throttle channel of the receiver and ultimately into the gyro.

I resolved the issue by adding a short servo extension to the ESC cable and clipping the power (red) wire on the extension so NO POWER was being transmitted from the ESC/BEC to the receiver. I added a cable from the receiver to the last open port on the gyro (for power) and added a 7.4V Lipo to power the receiver separately.

No more glitches!

Who wants to share his settings data of his Roban EC135/130 with BD Axon with me?
I've been looking for the right setup of the Axon in the EC130 for several days now and can't get the right feeling to fly it, Engine is a Hacker A50-12L Turnado V4, Esc a jeti Mezon 130, Servos: Savox 3x SA-1258 TG Swash, 1x 1283SG tail (30Kg/cm) on the video you can see the first flights, there was quite a bit of wind (4Bft)

ive got my md500 500 sz with trex 500 mechs and mini v bar fbl my tail pitch control is not behaving as should its not responding to right stick commands under load so when l spool up and l give right rudder it does not respond if l give left rud it works then after left command the right will respond but wont give enough pitch to control the helicopter l can replicate the issue by light touch of the tail blade while giving right command.
funny thing the unit compansation is correct when l swing the modle left to right end to end

Hey Guys, if you use the Bavarian Demon 3SX or 3X, know this: Windows 11 and the Demon software do not mix! If you have a MacBook Pro with M1 chip, like I do, even running Parallels won’t work because Parallels won’t run Windows 10 WHICH DOES WORK with the old Demon software.

SOOOO I hopped on Amazon and found this $189 Avita WT9M10! I enabled .Net 3.5 (under Windows Features) and turned off “S” mode. Just like that, I now have a portable, touchscreen device for my 3SX and my Axon helis!