How to engage Idle up?

[jmillett]

Hello all!

With the help of you guys, I have been happily hovering and flying circuits in Normal mode with my Raptor 50! Great fun!

I am looking at moving to the Idle up mode flying but I am unsure when or how to turn it on.

I have programed my JR radio with the recomended thortle curves for each mode. When the heli is just about ready to lift off I have tried flicking the Idle up switch quickly to the on position. As I do this the RPM increases dramaticaly, and the heli tries to push itself into the ground!

How do you do it? do you fool with the sub-trims on idle up so that the heli stays neutra when you swith modes?


My bigest fear is that when I swich modes I will have too much posite pitch and the thing will go out of sight in 10 seconds or less!


As always, any help would be greatly appreciated, or If this question has been answered in a different thread, and you can point me there that would be great!

[ClayK]

You don't really want to flick the Idle up switch while on the ground. You'll only be throwing the engine completely into the upper power band (if your throttle curves are correct) and dumping a load of negative pitch in. First, establish a good hover in normal mode (should be just above half stick) and then flip the idle up switch. At this point, your pitch should be about the same between normal and idle 1, if your curves are right. Your bird won't fly off on you.

Not sure how your curves are set up, but my normal, idle 1 and idle 2 are a complete linear from -10 to +10. I started with my normal -4 to +10 (my idles were -10 to +10), this was to prevent me from chop sticking the bird into the ground. I've become a little softer on the sticks and have made all my pitch curves linear. However, regardless of which way your pitch curves are set up, they should all be the same from midstick up to full stick.

At least this was how I understand it.

[ClayK]

Here's some reading. Normally I don't reference other threads as I like to have the answer right in front of me, but there is some good information in the three below as well.

http://www.helifreak.com/about11993.html&highlight=pitch+curve+idle

http://www.helifreak.com/about11993.html&highlight=pitch+curve+idle

http://www.helifreak.com/about6795.html&highlight=pitch+curve+idle

[DebianDog]

I actually DO like to flick it on the ground. Bring it to mid stick. Let the engine settle. Flick her to IU. Give her a few negative pumps. Let her eat!

Marcus Kim is the best example of this. (http://www.augustoheli.com/videostuff/videoarchive/HelifreakArchive/M/MarkusKimIRCHA2005.wmv)

Not a "beginner" move though

[jmillett]

Thanks for the help Clay!

I will check into these other threads as well!

[Espeefan]

I prefer hitting idle up while on the ground too. Throttle/collective stick about half or around 0 degrees pitch, and then hit idle up 1. That way the engine can bring up the RPMs with a very light load, and you don't have to worry about the heli jumping around or the tail twitching from the sudden torque/RPM increase, like you might if you were already in a hover. Of course if you fly a symetrical pitch curve in all flight modes, your heli shouldn't jump much, and depending on your gyro, tail twitching may not be a problem either.

[DavidH]

Most pilots now engage idle up when the model is sitting on the ground. That is how they do the pirouetting takeoffs and other maneuvers right off the deck.

No big deal to engage idle up with the model sitting on the ground. Just don't mess the cyclic alot while it is sitting there running.

David

[jmillett]

I think I am getting the idea! I guess whether I engage on the ground or in the air the key is to get the curve around center stick about the same for both modes so the Heli doesn't push itself into the ground or leap into the air.

Thank you all for your input!, This is a great site for a beginner like myself, It is an excellant resource.


Thanks Again

John