my @packet_fields = qw(	ident
			flags
			x
			y
			mode3
			callsign
			route
			spare1
			spare2
			flight_level
			terminator
			chksum
			);
my @rotation_packet_fields = qw(ident
				RDP_Ident
				Radar_Site_Ident
				site_x
				site_y
				Useful_Vol_Upper
				Useful_Vol_Lower
				Useful_Vol_North
				Useful_Vol_South
				Useful_Vol_East
				Useful_Vol_West
				Rotation
				Rotation_x
				Rotation_y
				Reserved
				QNH_Datum
				terminator
				chksum
				);