don't crash if fgfs is called with an invalid argument to the --vor option

diff --git a/src/Navaids/navlist.cxx b/src/Navaids/navlist.cxx
index 7f8cb72bbb6860e54551bad347bdb38951048803..80ba3c897155d0c2d7e03bb174c49d568645da53 100644 (file)
--- a/src/Navaids/navlist.cxx
+++ b/src/Navaids/navlist.cxx
@@ -167,7 +167,7 @@ FGNavRecord *FGNavList::findByIdentAndFreq( const char* ident, const double freq
                 return stations[i];
             }
         }
-    } else {
+    } else if (stations.size()) {
         return stations[0];
     }