I was wanting to try out some auto rotations on my Raptor 50 and even attempted them this weekend.
Here is how i started out :
- Baby autos - With the heli hovering at 5 feet. I flicked the hold switch ! The heli stayed there for a brief moment and started descending. Added collective as it came down and it settled nicely. Was fun to note that the heli did not immidiately start descending when the hold switch was flicked.

I did this several times. Since i was aware of how boom strikes can happen when doing autos, i did not really attempt to do this higher up.
But, i did try to do this a couple of times :
With the heli in idleup mode, and the RPM locked by governor, I got the heli up to around 50 ft. then i reduced collective to nearly 0 and let the heli start falling down, At around 8 feet i started feeding in collective that got back to hover at around 5 feet nicely. I did this a few times to get a feel of how the heli looks/behaves when coming straight down.

I do want to practise more autos. But want to know :
1. if having a forward speed is a must  ?
2. What are the ways to reduce the boom strike.
3. How much negative pitch should be given,
4. When at bottom and i get the engine back on, how to avoid it from doing piros( i have heard this happens ) , since the engine spools up quickly and the rudder is deflected at one end while coming down .

Thanks !
Gaurav

My experience :

1.  Forward speed helps, but you have to be careful with elevator management during the flare.

2.  I make sure the blades are pretty well tightened (have to apply some amount of pressure for them to turn on the holder.  The next thing is how one manages the "impact" of the landing (how clean it is).

3.  My experience is that for coming down, we need around -4, and the flare is about +1.  Remember the headspeed actually goes up during the flare, giving you that margin to complete the landing after the flare.  The amount of negative needed can be identified by the sound of the blades while coming down, there is a distinct (sort of fluttering) sound if the amount of negative pitch is appropriate.  At this pitch, the way the blades interact with the air allows the headspeed to remain pretty much constant (and that allows you to auto from even 400 or 500 feet).

4. First of all, you should do planned autos from "normal" mode as much as possible, so you will not spool the engine back into idle up right away when you abort the auto or when you take off after finishing the auto.  That alone should take care of this pretty much.

Quote from: anwar on April 19, 2010, 12:41:26 PM
4. First of all, you should do planned autos from "normal" mode as much as possible, so you will not spool the engine back into idle up right away when you abort the auto or when you take off after finishing the auto.  That alone should take care of this pretty much.

Since I have a governor, how would this matter ? I mean if I did the auto in IdleUp mode, the governor would keep the RPM locked, and that should be OK ?

Most people do not lock the head-speed using a governor in normal mode.  They use the governor only to prevent the headspeed from going over a certain limit (on goverors which have that capability), or just no not engage the governor at all in normal mode.

"Throttle hold" overrides all other modes (normal and idle 1, 2 and 3).  So even if hold is hit from idle-up, the governor disengages.  When you exit the hold and go directly into idle-up, that is not a good idea in general (jumping from idle rpm to very high rpm in a split second).