What are the advantages of converting to flybarless?
- Less weight
- Longer flight times for electric helis
- Far less linkage slop
- Ability to give faster cyclic rates, without losing stability
- Lower rotor head repair costs
- Adjustable flight characteristics
- Cleaner, less “model like” appearance
- Quieter, more realistic rotor sound
What will a helicopter converted to flybarless with the SK-360 fly like?
The gyro provides solid “neutral” stability in the pitch and roll axes (aileron and elevator).
This means that if you let go of the sticks, it will hold to whatever attitude it is currently at. If you put it in a perfectly level hover, it should stay there hands-off for some time, even in wind. If you’re in forward flight, it will stay in forward flight with no tendency to pitch up or down.
Note that it will not level your helicopter out for you. The control feel is similar to a “heading hold” tail gyro, but applied to pitch and roll as well.
The 3D videos look crazy, can I fly a heli flybarless without being an expert?
Yes. It isn’t any harder to fly a flybarless heli with the SK-360, than a heli with a flybar. It’s just a little different, and in some ways easier. The videos demonstrate how much of a thrashing the SK-360 can take, and still maintain the stability of the helicopter. It will hold a hover well, too.
Does it handle autorotations safely?
Yes. A heli equipped with the SK-360 will remain stable and completely controllable during autorotations. The main difference is that the control sensitivity will stay roughly the same at lower rpms, rather than being less as with a flybar. Autorotation “glide” performance should be improved with the drag of the flybar removed.
What Models of Helicopter can I use it on?
The gyro has seen thousands of flights on helis such as the Blade CP, Blade 400, X-400, Mini Titan, Trex-450, Trex-500, Logo 500, Evo 50 (nitro), Xtreme 50 (nitro), Trex e600, Trex n600, and Raptor e620 with good to excellent results. A wide variety of rotor head setups and blades have been tried, and while some work better than others, the gyro is fairly tolerant.
Where can I get a flybarless rotor head for my helicopter?
For some helis such as the Trex 600 and Logo series, rotor heads designed for flybarless operation are already on the market. For scale flight with 3-5 blades, any appropriate multi-bladed head should work.
Other helis can usually be converted using your existing rotorhead parts. Step-by-step can be found on web to convert the Trex 450 and 600 this way. Our media page also has photos of several conversions.
But as flybarless flight becomes more popular, a wide variety of for-purpose rotorheads are expected to enter the market in the near future.
What about Multi-Bladed Helicopters?
The gyro has flown in a 4-bladed and 5-balded Trex 450’s with no problems. The models fly rock solid in both hover and forward flight. The only difference from installing it in a 2-bladed helicopter was that the cyclic phasing had to be tweaked about 5-10 degrees from normal.
Can it use both digital and analog servos?
Yes, it is compatible with analog and digital servos. In analog servo mode, the servo outputs will be synchronized with the inputs from your radio, giving minimal control lag. In digital servo mode, frame rates of up to 125 Hz are available (a 2800rpm rotor is going around at only 47hz).
Why doesn’t it include a yaw gyro, if the other two axes are already there?
Because there would be no cost savings to the customer, especially since you probably already have a good yaw gyro. In addition, the physics of the yaw axis are different than pitch/roll, so we’d like to keep to our area of expertise and let you keep using your favourite tail gyro.
If the product is later improved, will I be left behind?
No. The hardware performs at or beyond its specifications, and it so is unlikely to be changed.
The SK-360’s firmware is easy to update using the included USB interface. If we find the software can be improved, you will be notified of any available updates. We believe past customers should benefit from new product improvements.
Full scale aviation provides a good model to follow here: they have achieved superhuman levels of reliability and safety through a system of feedback from mechanics to manufacturers, and back again (Airworthiness Directives and Service Bulletins).
Why does it need a PC/USB interface to set up? Wouldn’t it be better to put an LCD screen on it, or set it up like a speed control through the sticks?
In fact, it can be also be set up through a sticks-and-indicators interface, and for most purposes tuned using just the two gain dials (Bell, and Hiller) on the gyro’s face. However, we believe you’ll get better results by using the USB interface to do the initial set it up.
The USB interface allows the swash mixing functions of your transmitter to be moved onto the heli. This eliminates the loss in resolution caused by in-radio swash mixing, and lets you access features like phase trim, swash ring, and servo-speed-evening that otherwise only come on top-end radios. Because this involves dozens of settings, just as with a computer-radio a graphical interface is required.
An LCD interface was considered, but besides being breakable (glass), it would increase the weight, and drive up the cost. It would also severely limit mounting options. However, an external LCD field terminal will be available as a supporting product in future.
Will I have to bring a laptop to the field to tune it?
Usually no. The USB interface is provided to allow the full range of swash setup features; things like swash type, servo throws, servo type, and centering. Normal gain tuning is then carried out at the field, using the Bell and Hiller gain dials. Some advanced tuning features would require a laptop, but most users won’t need to change those.
What are the advantages over using weighted blades for flybarless?
- You can use a wide variety of stock rotor blades
- Safety: you don’t have to glue lead weights into the tips (which could become bullets)
- Without gyros to assist, a flybarless heli can behave oddly, such as pitching up in forward flight
- A digital flybar provides a locked-in feel similar to “Heading Hold”, rather than just the rate-damping effect of heavy blade tips.