diff --git a/ArduCopterMega/ArduCopterMega.pde b/ArduCopterMega/ArduCopterMega.pde
index 1f1fdf9409..316a76f72d 100644
--- a/ArduCopterMega/ArduCopterMega.pde
+++ b/ArduCopterMega/ArduCopterMega.pde
@@ -40,6 +40,7 @@ version 2.1 of the License, or (at your option) any later version.
 #include <RC_Channel.h>     // RC Channel Library
 #include <AP_RangeFinder.h>	// Range finder library
 
+#define MAVLINK_COMM_NUM_BUFFERS 2
 #include <GCS_MAVLink.h>    // MAVLink GCS definitions
 
 // Configuration