@vexilo- I have a version with a biplane. Not the ideal sillouette, but the best I could find.
pg-county-proposal-3-biplane.png
I had, however, another idea, based on PG county's proximity to Washington DC. In this flag, the triangle represents DC, (or rather the void that DC cuts out of the county), and showcases the county's location. The cross is taken from the current flag. The vertical part is curved slightly to represent the beltway, while the horizontal portion can represent Rt.50, which leads to the state capital. (Or alternately, Rt 4, which leads to the County capital). So it makes a symbolic map, of sorts.
PGcounty2.gif
The five stars represent the 5 regions of the county: Upper (Laurel, College Park, et al.), Inner Beltway (Capitol Heights, et al.), Central (Upper Marlboro, et al.), Southern (Fort Washington, et al.) and the Rural Tier(extreme E and SE, Brandywine and surrounding area).
The colors and quarterly nature of the flag were picked to represent the state of Maryland,

but note also that the 3 red stars (well 2 red and the counterchanged star) and two red lines refer to DC's flag.

Without further ado, here it is:
pg-county-mark3-d.png
I did a version with a Red triangle, and with a purple triangle, but this seems the simplest and most color-balanced.
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