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Old 01-20-2007 | 02:18 AM
  #5  
Truglodite
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Joined: Apr 2003
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From: Sac, CA
Default RE: tale of all tails

i agree with the idea of getting used to what you have and learning to fly it. after thinking about what i've done the past few months with my heli, i've realized that this is really all about getting hh to work with a high output tail setup.

i've found most high output setups are nice for rate mode, because revo mixing follows with perfect timing. with hh though, a gyro is trying to tell a motor to act some way to make the tail do what it wants it to do, even if the motor isn't up to the task. hh requires somewhat symmetrical force from the tail, but most high output tail motors accellerate/decellerate too assymmetrically for hh gyro's to understand (specifically, brushlesses accellerate too slowly at low rpms).

to understand you must think about internal input vs external forces (stick command vs wind/gyroscopic force). rate mode merely damps out the effect of external forces so the angular speed of the tail matches the input (rate=angular velocity control). ie: if you tell the tail to stop right there, the rate gyro might let the tail slide past a little, then hold it still. hh however, cares less about external forces and does whatever it technically needs to hold the tail in the position where it was told to, even if the motor isn't physically capable of holding it the way the gyro wants it to (hh=positional control). ie if you tell it to stop right there and the motor spools up too slow to stop it on the spot, the hh will say, "ok, we overshot, now we need to hit reverse and back up to that spot". that's what causes the dreaded bounce back, and we're left with slap happy tails in hh mode. it's pretty simple when you think about it for a minute.

i love the way my pro flies in rate mode, except in wind or flying backwards. now that i'm flirting with 3d, i'm concerned that rate mode might leave me hanging in some scenarios. too bad i got off work late today, or i'd be posting another test flight report with that long can geared setup.

btw futura, my long can is a 5300kV, that's probably why i'm overheating with a dd 4030. oh well, i'm going to fly this geared brushless and i'm going to like it.

[edit: i too have spent too much experimenting with my pro; enough to where i'd have half a trex 450se if i saved it all instead. look at me now, ppl would laugh if they saw a 450se in my garage after knowing all the money i've dropped on my pro. oh well, it's all good when we're airborn isn't it. besides, after the hell i've gone through with tail motors, flying a trex for the first time will be like loosing my virginity.]