This is the arms of the 24th Constabulary Squadron:

http://img144.imageshack.us/img144/6863/crestxz9.jpg

The Constabulary was a designation used by certain US forces in Germany 1946-1951. They where mainly redesignated Mech Cavalry,Tank Battalions ect. They carried out Border patrols and other security operations. The 24th was formerly 24th Reconnaissance Squadron.