diff --git a/Airbus/Airbus/MapsCollection.cs b/Airbus/Airbus/MapsCollection.cs
index c0936a0..a553232 100644
--- a/Airbus/Airbus/MapsCollection.cs
+++ b/Airbus/Airbus/MapsCollection.cs
@@ -130,7 +130,7 @@ namespace Airbus
         {
             get
             {
-                if(ind != String.Empty)
+                if(ind != string.Empty)
                 {
                     MapWithSetPlanesGeneric<IDrawningObject, AbstractMap> value;