I have always been flying with the NORMAL pitch & throttle curves. However, when flying on windy days, the wind pushes the helicopter up and down. If the TREX 500 goes to high, then I lower the left stick to bring the helicopter lower. The problem is, this also reduces the motor (head) speed and tail rotor speed, so I don’t have good control at this point. I then have to spool the motor back up as the helicopter gets to the correct altitude. So, now is the time to start using the IDLE-1 pitch & throttle curve. I”ll keep the IDLE-2 for 3D flight.

I’m using the IDLE-1 pitch and throttle curves recommended from the Align TREX500 manual. Today I took off in NORMAL mode, then flipped the switch to IDLE-1. The first thing I noticed was a drop in head speed, so I have to modify my throttle curve higher for IDLE-1. Then I noticed the there is negative pitch at the lower range. I’m not a big fan of negative pitch, maybe when I able to fly 3D, but for now, I don’t want negative pitch. So I have to modify my IDLE-1 pitch curve as well.

Throttle Curves:

Pos |  Norm  | Idle-1 | Idle-2

P5  |  100 %  | 100 % |  100 %

P4  |   85 %   |  85 %  |    93 %

P3  |   70 %   |  70 %  |    85 %

P2  |   40 %   |  70 %  |    93 %

P1  |      0 %   |  70 %  |  100 %

My values for the pitch curves are custom to my helicopter so I won’t publish them here.  The key point is that for NORMAL and IDLE-1, I don’t have any negative pitch.

The third thing I noticed was that my THROTTLE-CUT switch (A) is right beside the NORMAL/IDLE-1/IDLE-2 switch. When I went to land, I flipped SW-E from IDLE-1 to NORMAL….and hit the THROTTLE-CUT (SW-A) at the same time. I had to quickly un-flip SW-A. This happened twice!! So I need to move my THROTTLE CUT switch to the other side of the Futaba T7C radio.