I have been tasked with creating a series of chart types that don't appear to
be among those available with Flex 3. Most worrisome among these is a plot of
data vs 24-hour time. The graph should appear as a series of data points
plotted inside a circle with 'midnight' at the top and 'noon' on the bottom.
Inside of this would be some concentric rings and lots of x/y data.

How would I go about getting started creating such a chart type?

ILOG Elixir has a radar chart that looks like it might be able to be used as
you'd like.

If not, check out the plethora of other charting types they provide.

At a cost of course, but versus development timecost, probably a hell of a lot
cheaper to buy ILOG Elixir.

http://www.ilog.com/products/ilogelixir/

http://www.ilog.com/products/ilogeli.../radar-charts/

Hey look, a free radar chart:

http://www.adobe.com/cfusion/exchang...&extid=1698106