diff --git a/src/Model/modelmgr.cxx b/src/Model/modelmgr.cxx
index 3235f6190..4d59592a9 100644
--- a/src/Model/modelmgr.cxx
+++ b/src/Model/modelmgr.cxx
@@ -210,7 +210,7 @@ FGModelMgr::unbind ()
 {
     // work-around for FLIGHTGEAR-37D : crash when quitting during
     // early startup
-    if (!_listener) {
+    if (_listener) {
         _models->removeChangeListener(_listener.get());
     }