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xxxpongxxx
10-24-2010, 10:21 AM
hi there!

can anyone share how they set-up their heli for f3c?
throttle / pitch curves and whatever else i need to know?

thanks!

The Dude II
11-06-2010, 06:32 AM
Here's a list to get you started - each topic can be as deep a rabbit hole as you'd like.
I'm new to this part of the hobby, my first NATS was this summer - thought I had my setup "down" and just lacked practice - hindsight, still fine tuning things this week. I look at it as having ~ another 42 weeks of practice & more fine tuning!

CG
Typically a Contest model will have a neutral CG, balances on Main Shaft at take-off.
First maneuvers are Hovering - so the Heli should be as neutral as possible to help combat possible wind.
If Nitro, as your fuel buns off, it is usually preferred to have a further increasing nose-heavy model - as the "upstairs" portion of the aerobatics is largely in forward flight, certainly in Class 1 here in the US.
As your skills advance and you move higher in the Classes (2, 3 & F3C) - there is increasing backwards flight.
Electrics surely have an advantage here... as CG does not change as the electrons switch sides of the battery.


Pitch Curves
In General, for the Hovering portion, a Contest Model will have a relatively limited range as compared to a 3D setup...-3 to +8.
Depending on your personal preferences, you may choose to also have the Heli hovering at Center Stick - gives more resolution by increasing the stick travel form say 0 to 8 degrees.

Upstairs (aka Idle 1 or 2), a symmetrical pitch setup can be used - say +/- 10.

Throttle Curves
Though you certainly CAN fly using no governor...most of us still burning nitro run a governor. The crux of the game is consistency.
A rotorhead varying a few 10's of RPM will increase your pilot workload. Now - it's not just "easy-peasy, set & forget" with a gov. You'll be searching for that RPM (sweet spot) that yields the best hover.
Again upstairs - more like a 3D setup - you'll carry a good bit of headspeed.
For my 50-sized Nitro ~ 1675 for Hover, 1950 for upstairs.

Engine Tuning
Figure how to!

Radio Programming (F3C flight modes)
Biggest changes from a 3D setup - you'll be using your AFR/Dual Rate functions and some amount of Expo.
Example: my 3D setup has +/- 12 degrees collective & 9 degrees of cyclic & 20% expo on the right stick.
For the Hover, I will back the cyclic down to ~ 30% using the AFR function - this is triggered via the F3C flight mode switch (AKA flight mode or Idle-Up). The cyclic will be tamed to ~ 4-degrees and maybe 10% expo...feels like you just turned off your radio!
Becareful in the beginning not to let the heli get too far into a steep bank - as you may not have the cyclic and collective authority to level the model - yielding a crash - know where the flight mode switch is to flip back into a more aggressive setup (aka 3D) - and better yet - keep your focus and don't let the heli get ahead of you.
Probably never thought you'd hear that when just hovering!
Gusty winds are usually the culprit that will push the model into a bad situation - you've reduced your cyclic & collective so you can be precise but you loose the ability to "whip-it" right back as you may in a 3D configuration.

Head Setup
Depending upon your model, there are few to many options here.
Dampers, Flybar length & Ratio, Mixer arms ball position.
Again, the gist of it is to have a somewhat "tame" setup vs 3D.
Resolution (for precision) can be adjusted on the head by selecting different ball positions on the swash & mixer arms.
You'll want enough flybar authority to have the model sit well in the hover in breezy conditions - but not so slow that it kills the ability for the aerobatics portion.
The entire control system should be as silky smooth & slop-free as you can make it - again the word 'precise'!
A lot of time can be spent "blue-printing" the head to ensure it is the best it can be.

Blades & Paddles
Probably the biggest factor.
You'll want a heavier than "3D" style of blade - often labeled for Sport/FAI/Training.
The CG of the blade is further out on the blade vs a 3D - for stability.
Paddle wise - again a heavier paddle than 3D - and/or you may choose to add flybar weights to help the stabilty & slow the the cyclic response. The airfoil & size of the paddle is typically larger as well.


As mentioned, you can go into great detail within each of these - and with today's product availability - you have quite a few options. Time spent in exploring these can yield the solution that works best for you.

Good luck & go fly.. A LOT!