DA9021 - Don Ayers
Max thickness: 9.0% at x = 21.45% chord
Max camber: 2.1% at x = 33.83% chord
Available data sources:
JavaFoil+Calcfoil stall+Eppler ext transition
The first two digits represent the airfoil thickness in tenths of a percent.
The second two digits represent the camber in tenths of a percent.
Coordinates from https://www.rcgroups.com/forums/showthread.php?1016239-Download-airfoils-here