Unit Emblem Identification

[Rabe Anton]

Can any reader identify the unit emblem described below, which has appeared in photographs of at least three aircraft sold on eBay.de in recent weeks:

Go 145 C A + U S
Go 145 D D + E W
Fi 156 P B + Q S

The Wappen consists of a vertical rectangular field with triangular bottom, all thinly outlined black. The field is a medium color such as green, blue, or red. On this field appears a flying jack boot in black kicking a stone or ball. A small white wing is attached to the top of the boot. The emblem is displayed beneath the cabane struts or, in the case of the Fi 156, beneath the windscreen.

I should add that this Wappen does not seem to appear in any of Barry Ketley's publications. A source or reference would be appreciated.

Thanks to all for looking into this question.

RA