diff --git a/libraries/SITL/SITL.cpp b/libraries/SITL/SITL.cpp
index 12813224b3..d2135bf838 100644
--- a/libraries/SITL/SITL.cpp
+++ b/libraries/SITL/SITL.cpp
@@ -252,7 +252,7 @@ const AP_Param::GroupInfo SITL::var_info3[] = {
     AP_GROUPINFO("VICON_YAWERR",  19, SITL,  vicon_yaw_error, 0),
 
     // vicon message type mask
-    AP_GROUPINFO("VICON_TMASK",   20, SITL,  vicon_type_mask, 1),
+    AP_GROUPINFO("VICON_TMASK",   20, SITL,  vicon_type_mask, 3),
 
     // vicon velocity glitch in NED frame
     AP_GROUPINFO("VICON_VGLI",    21, SITL,  vicon_vel_glitch, 0),