View Full Version : Quad-Bladed Rotorhead
01-08-2010, 11:27 PM
ok the ? is do i need some thing else if i put on a quad-Bladed Rotorhead to make it work right .do i need some kind of electronic system for this? i dont see that a fly bar with this system..
01-09-2010, 02:10 AM
If you're not going to use a 3-axis gyro, typically known as flybarless (FBL) then you're going to be limited to hovering and mild forward flight.
I wouldn't bother with a quad head on this size heli. You might get your head speed down to a little over half, but it's still not going to look scale. That is assuming you're looking at a scale setup.
Not sure if anyone has gone FBL on the 250. The cyclic is already crazy fast on the thing.
01-09-2010, 02:34 AM
You'll be (by my calculations) doubling the torque that the head exerts on the heli if you add two more blades. This means halving the RPM to get the same lift, which in turn means getting a motor of half the KV.
You DO need a 3 axis gyro. The purpose of this is NOT to boost cyclic response, which on a 250, as heli-on correctly said, is faster than greased lightning on crack! The lack of flybar which a multiblade system requires will result in greater 'ballooning' of the heli in fast forward flight. Have you ever noticed your 250's slight tendency to pitch 'up' as you get it past sprinting pace? Ie, you had to use slightly more forward cyclic at high speed than, say, walking pace? In a flybarless heli with no alternate stabilisation, this effect is greatly amplified. In the days before the 3 axis systems, pilots who couldn't bear to have their rotor head anything but true to scale would experience severe problems with high speed, low altitude passes or this reason.
Hope that helps! :)
01-09-2010, 02:56 AM
thank you all for the info i think im just going to live it as is