diff --git a/ArduCopter/APM_Config.h b/ArduCopter/APM_Config.h
index 15372c99bb..0bf95dcf89 100644
--- a/ArduCopter/APM_Config.h
+++ b/ArduCopter/APM_Config.h
@@ -33,10 +33,9 @@
 //#define EPM_ENABLED           ENABLED             // enable epm cargo gripper costs 500bytes of flash
 //#define CLI_ENABLED           ENABLED             // enable the CLI (command-line-interface) at a cost of 21K of flash space
 //#define NAV_GUIDED            ENABLED             // enable external navigation computer to control vehicle through MAV_CMD_NAV_GUIDED mission commands
-//#define OPTFLOW               ENABLED             // enable optical flow sensor and OF_LOITER flight mode at a cost of 5K of flash space
+#define OPTFLOW               ENABLED             // enable optical flow sensor and OF_LOITER flight mode at a cost of 5K of flash space
 
 // features below are disabled by default on all boards
-#define OPTFLOW               ENABLED             // enable optical flow sensor and OF_LOITER flight mode at a cost of 5K of flash space
 //#define SPRAYER               ENABLED             // enable the crop sprayer feature (two ESC controlled pumps the speed of which depends upon the vehicle's horizontal velocity)
 
 // other settings