helojerry
Posts: 73
Joined: 4/17/2008
From: Phoenix,
AZ, USA
Status: offline
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quote:
ORIGINAL: billmay
quote:
ORIGINAL: helojerry
Something else I'm curious about. The whole rotor disk tilts with respect to the heli when the cyclic control is moved.
Jerry
The reason it's called a "cyclic" is because the control is actually "cyclical" in nature (meaning the action only occurs during a part of the rotor rotation cycle). To understand it better, power up the heli but keep the throttle at zero. Now move the cyclic in one direction. Lets' say give it right cyclic. Start with the main rotors aligned for/aft with the flybar out to the sides. When you give right cyclic nothing happens. Now hold right cyclic and manually rotate the main rotors clockwise. When the rotor is sideways you'll see that the flybar paddles are now pointing downward toward the right. When the rotors move back to the fore/aft position the paddles go back to neutral. The only thing that ever moves is the flybar paddles (and then only during part of the rotation cycle). The main rotors and the heli just follow. That's why there is no control without the flybar paddles on. Although there is obviously some blade flexing and general flexing occurring, it's actually the cyclical change in the direction of the flybar paddles that is causing the flybar to tilt and, as a result, the entire heli and the main rotor to tilt. The solid aluminum rotor core just reduces flexing which is probably a good thing.
 Yeah, I think a pretty much understand how cyclic pitch works on the model and the real thing. I'm not talking about the mechanism. I'm talking about how the rotor disk moves with application of cyclic pitch. As Radd says, you can watch the top of the center axis (mast) tilt (plastic on the stock Falcon) because it tells which way the heli is going to go before it goes there. As the center axis tilts and the rotor disk (the path the the blades travel describes a circular disk) tilts with it. When the helicopter is on the ground, that means that something is bending because the skids are still flat on the ground. If the tilt is toward the rear, the tip of the blade can hit the boom ie. boom strike occurs.
Anyway, the main shaft (steel) that is driven by the gear is probably not bending. Something sure is. If the center core (top of the mast) is made stiffer, is this tilting of the rotor with respect to the helicopter body reduced? do the rotor blades flex more instead? or do the skids lift off the ground before flying rotor speed is reached?
Jerry
From Radd's School of Flight
At this point in your training the huge spinning rotor disk is way too intimidating and also way to late to get you out of trouble..The mast is the pumbob of a helicopter and which ever way it moves or tilts is an indicator of which way the chopper IS going to move...Notice how I capitalized IS?...The mast moves first in realtionship to the controls on your radio. It's movements can be noticed in very slight changes. Before any other part of the heli can react the mast has to move first. In flight or Hover the mast will show you the intent of the heli before it ever happens. Which ever way it tilts that is the way the machine is going to go. By watching the mast you can actually be ahead of the helicopter in a hover, correct it and think ahead before the chopper has even moved..Cool Huh?
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All Forums >> RC Helicopters >> Electric RC Helis >> RE: Falcon 40 (Exceed heli) Forum 
RE: Falcon 40 (Exceed heli) Forum - 
Like I said though I have accidently had my hand in the way and stalled it during bench testing and the 4a fuse dosen't even budge which leads me to believe that it doesn't pull enough to blow the mosfet. You know though if Gau is blowing 100a mosfets then anything is possible. 
