diff --git a/src/Main/options.cxx b/src/Main/options.cxx
index f2d0a2d..b163674 100644
--- a/src/Main/options.cxx
+++ b/src/Main/options.cxx
@@ -271,6 +271,18 @@ void fgSetDefaults ()
     char* envp = ::getenv( "http_proxy" );
     if( envp != nullptr )
       fgSetupProxy( envp );
+
+    //zhongjin
+    //Addon
+    SGPath addonPath = globals->get_fg_root();
+    addonPath.append("Addon/RedGriffinATC");
+
+    try {
+      addonManager->registerAddon(addonPath);
+    } catch (const sg_exception &e) {
+      string msg = "Error registering an add-on: " + e.getFormattedMessage();
+      SG_LOG(SG_GENERAL, SG_ALERT, msg);
+    }
 }
 
 ///////////////////////////////////////////////////////////////////////////////