Model Forum / Radio Controlled / Helicopters / March 2006

Damn H, I hope you're talking engine rpms there!  ;-)

Your idea of keeping normal and idle up 1 identical is a very good idea,
especially with the collective.  Doing that will insure that nothing
unexpected happens when you flip the switch.  I'm assuming you meant 1,600
rpm for the main rotor speed.  That's a nice healthy rotor speed for must
about anything from a 30 on up.  You don't really need anything more than
that for simple forward flight so I wouldn't bother with trying to program a
different rpm unless you really want to.

As for when to flip the switch, in this case, any time after the clutch is
fully engaged should work just fine.  You won't want to flip the switch when
the rotor is spinning slowly with the clutch disengaged.  Doing that will
bring on the power more abruptly than you want.  If you're idle up setting
are relatively mild, it probably won't hurt a thing.  If they're aggressive
enough, you could momentarily fold the rotor blades back in the blade grips
and risk a boom strike.  If you got the rotor spinning nicely, whether it's
off the ground or not, before flipping to idle up 1, you won't have a
problem.

What you're asking is a "very" common first use for idle up 1.  As you gain
experience, you'll find that idle up's can be used for just about anything
you want.  In this case, start with small differences between normal and
idle up 1.  Then increase them little by little so you can gain an
understanding of what's happening.  Best of luck and have fun!

Fly Safe,
Steve R.

You don't need dli-up for circuit flying or even basic aerobatics Harry.
It's "nice", ut not necessary. Anyway, a governor is a FAR beter idea and
easier to set up.

Spool up, switch on, fly.

That's a very good starting point, but go with a touch more negative in the
bottom 1/4 of the stick travel too. (Can you have more of less I wonder?:-)

It's as correct as it needs to be at this time. Later on you may want to go
with a "V" shaped throttle curve in idle up 2 so you can play at upsidedowny
stuff, but that's a dy or two off I imagine.

Keep the idle up close to your "normal" curve with a little more neg and
you're moving in the right direction.

Your idle-ups can be used for pretty much whatever you want, where you don't
want the engine to drop back to idle when you bottom the stick.....hence the
term, 'idle up'.

I've got my heli set up so that I've got:

Take-off mode (no idle up): 1500rpm and -1 pitch at bottom stick.  I only
use this mode for takeoff and landing.  The lower head speed makes the heli
much less twitchy in the hover.
Idle-up 1: 1650rpm and -4 at bottom stick.  I use this mode for general
flying about and basic aeros (loops and rolls etc).
Idle-up 2: 1650rpm and full V curve for pitch.  I only use this for doing
moonslides and stuff that requires full negative pitch.

I use a headspeed governor as I could never manage to successfully stop the
head overspeed on descent, no matter how much I messed around with my
throttle curves.  It's *very* nice to have and means you can set up a basic
throttle curve (as a fall back in case the governor fails) and then forget
about it :-)

MrBonk
www.mrbonk.com