Tracking Problems? Try this...

Ever since I assemble my Piccolo I've had tracking problems even though everything on the flybar is square and even. Swapped head with my buddy John's Piccolo and no tracking problem... Talking to my buddy Roy (we both have LMH 100's) and he said adjust the linkage to the flybar on a fixed pitch heli to correct tracking.

This linkage is fixed on the Piccolo. Tightened the swashplate but this didn't help. What's left? The Flybar Control Arms (#67561)...!

Place colored tape on one blade. Run up the Piccolo while holding it and find the low tracking blade. Adjust the Control Arm 90 degrees ahead of that blade, up 3 or 4 degrees. Try again. When you are done adjusting, that one arm will be way out of alignment with the Paddle but the Piccolo blade tracking will be great...! Use another hint from this BBS put a drop of Super Glue on the Paddles and on one control arm to stop them from moving when you have an "Ahhh Sh@*!". Leave one arm un-glued to allow things to move, instead of breaking, in a crash...

After a little trial and error you will get perfect tracking and better flight times...!
Please try it. Post me with your results (good or bad).

Good Luck

John L.

i got perfect tracking last night buy raising the pitch of one blade to have the same amount of lift as the other i did this buy using js pitch adjustment method (1mm screw in the rotor head)it felt weird to have one blade set different than the other but perfect tracking sure is a sexy thing and yes i reckon it was worth an extra 30seconds in fly time,this metod is good cause you dont have to feel in the dark for the settings .

John Boy,

I have used the method that you describe for eight weeks until I found that it unnecessarily wastes power.

IMHO, Will P is right, adjusting the angle of attack of one blade is the way to go. This will also lead to perfect tracking, if done properly, but not at the expense of added drag at the paddles.

BTW, I timed my flights with tracking 5mm off and with perfect tracking. The difference seems to be in the range of 25 seconds. I'm using Robert Lee's CFK blades.

Thanks for the input...!

I wonder if anyone has found a good reason for the tracking to be so different from Piccolo to Piccolo. Put my Pic head, complete with stiffener and blades, onto another Pic and the blade tracking was great. Moved it back to mine (checked arms and paddles each time) and the tracking was way off again.

Only difference I could see between the two would be the swashplate and the control links. Maybe someone has found the answer to these differences.

I know that moving the control arms will cause the flybar to create more drag but I was hoping that better tracking would more than make up for it. The drag increase is not as big an issue with a glow copter but critical on our small Pic's

I'm going to try the screw mod to adjust tracking next.

Thanks alot

John L.

When i take of my blades and replace the other way around it is always the same side that needs the extra pitch to track perfect,this tells me that the rotor head may have some indiferences (on mine anyway)i guess im nearing 500 flights with my chopper so after all that use it could be a little flexi(but once in track it is always the same so i guess it could be a minor molding flaw ,but i wouldnt expect that from Ikarus) but as i remember it it has always been out of track since day one untill yesterday .
John boy are you vibe free,you may have a bent main shaft?

[This message has been edited by will p (edited 12-09-2000).]

in a fixed pitch heli like the pic with flybars, the tracking is adjusted by adjusting the flybar paddles ( try to adjust them both so they are both as close to level as possible thus equalizing the drag of the two paddles.) if you have a pitch adj screw on the main blades then you can adjust it there as well. if the swashplate has a bent control arm it will have the same effect as a longer or shorter control link thus increasing or decreasing the pitch of the flybar on that side. thus if your helicopter had a warped or bent swashplate that would cause the blades track improperly where they may be perfect on your buddy's heli(and swashplate). you should really track the flybars instead of the main blades. try painting a small mark on one of the flybar paddles, then adjust them to track perfectly(with both paddles as close to flat as possible). this should bring the main blades into track as well. if not then adjust the pitch of the main blades with the adjustment screw you added. in the end you want all blades tracking evenly. anything less will cause drag and wasted flying time.

[pgoelz]

Correct me if I'm wrong here, but.... I believe it is actually pretty easy to tell if a tracking problem is coming from the flybar or the main rotor.

Take a close look at the rotor system at hover power. If the flybar tracks perfectly and the main rotor does not, the problem is unequal pitch on the two main rotor blades.

If however, the flybar and the main rotor BOTH are out of track, then the problem COULD BE the flybar tracking. This is caused by both paddles not being absolutely level all the way around the disc. Correct the flybar tracking (with the main blades removed?) and then re-examine the main rotor tracking. If the tracking is now good, you're done. If the tracking is still off, you need to adjust the pithc of one main rotor blade.

You can correct an out of track condition in the main blades by adjusting the flybar, but as others have said, it masks the real problem and wastes power.



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Paul Goelz
pgoelz (at) eaglequest (dot) com
Piccolo web page: http://www.eaglequest.com/~pgoelz/piccolo1.html