diff --git a/src/Aircraft/controls.hxx b/src/Aircraft/controls.hxx
index 00caa0b19..bd1717055 100644
--- a/src/Aircraft/controls.hxx
+++ b/src/Aircraft/controls.hxx
@@ -43,7 +43,7 @@ public:
 
     enum {
 	ALL_ENGINES = -1,
-	MAX_ENGINES = 10
+	MAX_ENGINES = 12
     };
 
     enum {