Engine Size And Weight
I have created this chart as a tool to aid in the design and building of R/C Model
Autogyro's. I have found this chart to he a very useful tool when trying
to calculate a Gyro's Rotor Diameter, Engine Size and Maximum Weight Limits. The chart was designed with the Rotor Diameter along the bottom in 2 Inch
increments and The Engine Size in cubic inches and Weight in oz.
along the left side of the chart. ** Please note ** that the Engine and Weight s share a common scale. It is necessary to drop the decimal point when making a Weight calculation.
For example .45 equals 45 oz. and 1.25 equals 125 oz.
To Determine the engine size for a given rotor diameter:
First select the desired Rotor Dia. from the bottom of the chart
Follow the lineup to the intersects the straight "Angled Line" and Then
follow the dotted line to the left side ofthe chart and this will be the correct
Engine size in cu. In. for the Rotor Disk Diameter you have chosen.
To Determine the maximum weight for a model with a given Rotor Disk Diameter, based on a disk load of five (5) ounces per square foot:
- First select the desired Rotor Dia. from the bottom of the chart
- Follow the lineup to the intersection point of the "Curved Line" and
then follow the doted line to the left side of the chart and This will be the
maximum recommended weight, in ounces, that the model should be for a Disc Loading of
5 ounces per square foot..
Note #1: The number of blades in your rotor is insignificant to the results obtained with this chart.... in otherwords,
don`t worry about it.
Note #2: For more information on this "5 ounces per square foot" disk loading mentioned by Rick,
please check Jim Baxter`s Flight Prediction chart.
rev 11-10-98.. jb
