Radio Control Scale Aerobatics
By John Glezellis
Throttle curves add power where the pilot needs it
LAST TIME, I wrote about the benefits of using both Flight Modes and Flight Conditions to make you a better pilot while simplifying life. This month I will continue to explore your computer radio's capabilities by looking at the benefits to using a throttle curve and the general steps that are associated with programming your computer radio.
The example aircraft for the month is my Katana S. For the past few years I have flown these airplanes with the Desert Aircraft 150cc engine and KS 1090 pipe.
I recently replaced the 150cc power plant with the new DA-170, which has phenomenal performance and has added a lot of "punch" to the model's flight characteristics. In changing the engine I also adjusted my throttle curve.
Please note that the pictures in this column do not reflect my personal throttle-curve settings. They are for visual purposes only.
It is important to mention that engines respond differently depending on the exhaust system that is being used. And you should adjust the high- and low-end needles according to the elevation at which you are flying and the outdoor temperature. If you are flying in an extremely humid environment and find that your engine is extremely rich after a 10-minute flight, I recommend you lean it a touch.
Before you begin taking advantage of your computer radio and adding a throttle curve (given the notion that your computer radio supports a throttle-curve feature), it is important to select the correct propeller for your model. The propeller you choose will differ depending on the elevation at which you fly.
When I fly the 39% Katana S at my home field in Massachusetts (which is located roughly 40 feet above sea level), I prefer to use a Mejzlik 32 x 10 two-blade propeller. However, when I fly at fields that are above 1,500 feet in elevation, I prefer to use a Mejzlik 30 x 12 two-blade.
Using different propellers may require that you adjust your throttle curve slightly when changing between the two. On heavier propellers such as the Bolly 31.5 x 12 two-blade, you will notice a slower transition time from low to high throttle. As a result, a more linear throttle curve may be desired when you use a heavier propeller. Regardless, choose your propeller and then tamper with your throttle curve.
The example transmitter for this column will be the new JR 12X. Although all transmitters are different, please use this column as a basis for programming a throttle curve. Then reference the instruction manual that was provided with your computer radio to see what the process behind programming a throttle curve entails.
On this system, two throttle curves can be set on two different flight modes. This is neat,
Transcribed from original scans by AI. Minor OCR errors may remain.
