diff --git a/ArduPlane/Plane.h b/ArduPlane/Plane.h
index 9caf84df07..145a44e2f1 100644
--- a/ArduPlane/Plane.h
+++ b/ArduPlane/Plane.h
@@ -136,6 +136,8 @@ public:
     friend class RC_Channels_Plane;
     friend class Tailsitter;
     friend class Tiltrotor;
+    friend class SLT_Transition;
+    friend class Tailsitter_Transition;
 
     friend class Mode;
     friend class ModeCircle;