diff --git a/ArduCopter/defines.h b/ArduCopter/defines.h
index 0728281604..2882b89a24 100644
--- a/ArduCopter/defines.h
+++ b/ArduCopter/defines.h
@@ -152,6 +152,9 @@
 
 // altitude controller
 #define CH6_THR_HOLD_KP 14
+#define CH6_Z_GAIN 15
+#define CH6_THRUST 16
+
 
 // nav byte mask
 // -------------