Airfoil ListAirfoil_List 

Other Available Tabs;

Airfoil TabAirfoil_Tab 

Airfoil Coordinates TabAirfoil_Coordinates_Tab 

Lift Graph TabLift_Graph_Tab 

Lift Drag Data Maintenance TabLift_Drag_Data_Maintenance_Tab 

Airfoil CAD TabAirfoil_CAD_Tab 


To get to this Tab

1. Open the Airfoil List screen by selecting the Airfoil List menu item from the File Menu or

click on the Airfoil List toolbar button.

2. Click on the Polar Graph Tab.


This graph displays lift coefficient vs. drag coefficient for the selected airfoil. Data is provided for a number of Reynolds number readings. Data for this tab can be entered through the Lift/Drag Data Tab or can be imported from the SOARTECH LIFT/DRAG DATA IMPORTSOARTECH_LIFT_DRAG_DATA_IMPORT screen.

As model aircraft typically fly at low Reynolds numbers (ie; small wing chords at low speeds) an airfoil which has a high lift coefficient and low drag coefficient at a low Reynolds number will have the best all-round performance. In general most airfoils suffer a loss in performance with a reduction in Reynolds numbers. If you choose an airfoil which performs well at a low Reynolds number , the same airfoil will typically perform much better at higher Reynolds numbers. 

To determine the reynolds number for a wing or tail design use the REYNOLDS NUMBER GRAPHREYNOLDS_NUMBER_GRAPH_SCREEN facility provided with the WING CAD SCREENWING_CAD  The higher the lift coefficient(Cl) the greater the lift produced by an airfoil and the lower the stall speed for a given wing area. The lower the drag coefficient(Cd) , the lower the profile drag for a given wing or tail area. Low drag is required for Pylon and Sailplane designs. Funfly designs rely on high drag sections for even speed through manoeuvres. Please note that this data is for infinite aspect ratios . The actual lift and drag coefficients for real designs will be lower and higher depending on the Aspect Ratio of the wing or tail. Aspect ratio is calculated as follows;

Ratio = ( Wing Span)2    /   Wing Area 

High Aspect Ratio (long narrow wings) reduces Induced drag but lowers Reynolds Number (low airfoil performance) and increases structural loading (good for gliding). Reduces roll rate (high inertia).

Low Aspect Ratio (short wide wings) increases Induced drag but increases Reynolds Number (good airfoil performance) and reduces structural loading ( good for aerobatics). Improves roll rate.

The higher the Aspect Ratio the closer the performance of the wing or tail will match the test data.


There are two buttons on this screen.

Save Button

This button provides the capability to save the currently viewed graph as a windows bitmap graphic file. The graphic file can be viewed at a later date or pasted into a document.


Compare Button

This button provides the capability to perform an Airfoil ComparisonAirfoil_Comparison .


To print the graph

Select the PRINT menu item in the FILE menu or click on the tool bar button.