Flybarless R/C Helicopter - Getting more popular.

[Super-Hornet]

Flybarless Helicopter is getting more and more popular nowadays.
Take a look at latest edition of "Model Helicopter World". Inside you will see some true scale heli (ranger) in flybarless and lama with 3 rotor blades.

It also has picture of latest Logo 10 in flybarless.

Previously, most R/C flybarless uses gyros and mixer or weighted tip blades for stability. Now since flybarless is getting more popular, Mikado produces their own stabilization system for flybarless.
It is called "Virtual Flybar System". There are few more. There is "V-Stab" or "VStabi" also.

Now I waiting for Mikado to release their Virtual Flybar system to the market and hope it is not expensive.

Here are some picture of Virtual Flybar system and also a video using VStabi. Enjoy.

http://www.ulrich-roehr.de/hubi/e-power18/galerie/factor.wmv

SH

[Heli Lim]

fLTBARLESS RC HELI

SH im going to takeout my flybar soon

[Super-Hornet]

Hi Heli Lim... Welcome to the party!!

I personally prefer flybarless or multibladed. It make R/C heli more realistic look. U also learn new thing about heli also.

Some knowledge I going to pass to you when u go flybarless..
Flybarless heli fly slightly different from flybar heli. If you do not have any other mean of stability, your heli will be difficult to tame. The bigger the heli is, the more stable it goes (So far for me TRex is the biggest flybarless I go. Not sure about Raptor size)

SH

[ethinger]

SH...
going flybarless is ubstable for helis... would real helis benefit by using flybars?

[Super-Hornet]

If you look carefully in real heli, their rotor head is much much much complicated!. You have rigid, semi-rigids and teeter design. Then u have fully articulated rotor head also.

Older heli like Bell 47 has flybar+paddles. It is like those Hornet II kind of head. In UH-1, they do not use flybar+paddles design but they use stabilizer arm instead. It is like flybar with weight.

All those design in Bell 47 and UH-1 is to make heli stable. The problem of those design is that its cyclics is slower/or sluggish and it is limited by only 2 blades (Due to flybar+paddles/weight is 90Degree to blades)

For more than 2 blades, you can't use flybar. Therefore, u need other means to stabilize it. Therefore, in real heli, normally u see they have rigid/semi-rigids/teeter design and most heli nowadays uses SCAS (Stability Control Augmentation System). It is like having gyros on those cyclic axis.

SH

[Heli Lim]

fLTBARLESS RC HELI

Look at this heli ther r flybarless http://www.helispot.com/photos/0027h...tml/03003.html

[Heli Lim]

fLTBARLESS RC HELI

Resend with pics.

[Heli Lim]

fLTBARLESS RC HELI

Repost with pics.

[Super-Hornet]

So, Heli Lim.... Are u going to create a R/C Full scale of Jet Ranger?

Anyway, some correction to my previous post:
Bell 47 is created by Bell Helicopter. During that time, there are 2 person come out of a good way to stabilize heli. U have Arthur Young, who work in Bell Helicopter and other is Stanley Hiller (Different company).

Bell adopt Flybar+Weight design while Stanley Hiller adopt Flybar+Paddles design (Now u know why our R/C heli is either Hiller or Bell+Hiller design).

For Stanley Hiller, one of his paddles heli is "Hiller H-23 or UH-23".

Here are some pictures of UH-23:

[Super-Hornet]

For Bell 47:

[Super-Hornet]

For most real heli rotor head (and tail rotor also) close up pictures:

http://www.b-domke.de/AviationImages/Rotorhead.html

[Brandon Chng]

SH:would a flybarless heli benifit from having heavier blades? i'm aware that full scale can get the required stability from heavy blades. how was your exp on blade weight?

btw from the full scale helis i've seen, one thing which caught my eye was the really small size of the control rod/links to control the blade grips. from what we use in r/c, it almost looked like the link would break off even in a hover...incredible

[Super-Hornet]

I read it from somewhere in the internet and I can't find back that URL anymore. From there, it does mention that while Arthur Young go for flybar+weight and Standley Hiller go for flybar+paddles, Igor Sikorsky go for multibladed weighted tip rotor blades.

I did not try weighted tip in my flybarless. The first time I tried weighted tip in Hornet II with bad result. The weight flew off like shooting bullets.

If u want to try in TRex or anything similar in TRex with wooden blades, one easy way to create weighted tip is to drill a hole near the tip. Then use screw and nuts across the hole to create weight. Different weight can be achieve by using number of nuts.

Using weighted tip blades should be able to make flybarless heli stable whereby u actually making the whole disc/rotor as gyroscopic inertial effect. The advantages is that it is the easiest to do and the cheapest. The disadvantages is that U have to get the correct weight on the tip. More weight meanning more "damping effect" or gyroscopic effect but it also affect the cyclic sensitivity. The other disadvantages will be it will create more stress to the rotor head and also u need to build your own weighted blades.

The advantage of using electronics stability (like SCAS or VStabi or Virtual Flybar System) is that the amount of "damping effect" and cyclic can be easily controlled by adjusting the gain of the SCAS/VStabi/VFS. Another good thing of it is that u can use normal, unmodified blades. Because u use normal blades, the stress to rotor head is the same as normal flybared design. The disadvantage of using SCAS/VStabi/VFS is that it COST MORE!

SH

[Super-Hornet]

Igor Sikorsky using weigted tip blades for what I know is during the earlier stage of his helicopter development.

Even though I did not see a real heli rotor blades close up or work on it, I doubt most real heli uses weighted tip for stability. For what I suspect is that all real heli rotor blades do have weight near the tip but that is for CG balancing. Just like our R/C heli. Most real heli nowadays uses avionics to stabilize the heli instead. (SCAS)

SH

[Heli Lim]

fLTBARLESS RC HELI

This bell flybarless