Tag Archives: how to

RC Helicopter Curves

This is how I do my curves on my helicopters. It is very basic set up and the curves and speed my change from heli to heli. This can be a good baseline for setup and you may tune your own curves from here.

First before setting up any curves make sure your helicopter motor is disabled.

The first thing I do is set up 4 curves, 2 throttle curves and 2 pitch curves. First let us look at the Normal mode Curves.

Normal Mode

Normal Mode Throttle Curve
Normal Mode Pitch Curve


I have set the throttle speed for normal mode at 80% throttle. When you throttle up the head speed goes from 0 to 80% by mid stick (point 1). That why the head speed will be full when you start to add pitch. Pitch will be at 0 when the throttle is at  when the head speed is 80 %. After this point you will not be adding head speed only pitch, as you move the throttle stick up. This way  when you switch to Idle up/stunt mode  the heli will not hop or drop. Also while in positive pitch if you switch to Idle Up/Stunt mode the head speed and the pitch will be the same. Note about negative pitch on normal mode — I always put some negative pitch on normal modes in case you need to hold the heli down tight during spin up, in windy conditions.

Idle UP/Stunt mode


Idle Up Throttle Curve
Idle Up Pitch Curve

When you switch to Idle Up/Stunt mode. You should be in a mild positive pitch. All positions above the center point (point 2should be the same in normal mode and Idle UP. Speed and Pitch will be the same. This way the heli will not move when you make the switch between modes.

Once the heli is off the ground you should switch to Idle Up and keep it there for the duration of your flight. This pitch curve gives you much more control during autos.

How to add and test a LUA script to Open TX Companion

LUA scripts can make the Taranis radio even more powerful. Here is a little how to with LUA scripts and testing of those scripts. The scripts used in the demo are listed below.

How to add a LUA script to Open TX Companion

OpenTX Companion Testing Telemetry Scripts 

This is the Temp LUA script.



— Temp Screen
— Version 0.5 Brad Kelley
— setup for Trex500
local escTemp = 0
local battTemp = 0
local function background()
escTemp = getValue(“Tmp1”)
battTemp = getValue(“Tmp2”)

local function run(event)


lcd.drawText(1,0,’Trex500 Temps’,INVERS)

lcd.drawText(1,15,’Batt Temp:’,0)

lcd.drawText(90,15,’ESC Temp:’,0)

return { background=background, run=run }



Here is the  Head speed Calc LUA script.



— Headspeed Calc
— Version 1.0 Brad Kelley
— setup for Trex500
local maingear = 162
local piniongear = 14
local rpm = 18000
local gearratio = 0
local headspeed = 0

local function init()
gearratio = math.floor((maingear / piniongear) * 100 ) / 100
rpm = getValue(“RPM”)
local function background()
rpm = getValue(“RPM”)

headspeed = math.floor((rpm / gearratio) * 100 ) / 100

local function run(event)

lcd.drawText(1,0,’Trex500 Headspeed’,INVERS)

lcd.drawText(1,15,’Main Gear:’,SMLSIZE)

lcd.drawText(1,22,’Pinion Gear:’,SMLSIZE)

lcd.drawText(1,29,’Gear Ratio:’,SMLSIZE)


lcd.drawText(90,15,’Head Speed:’,0)

return { init=init, background=background, run=run }