diff --git a/launch/gazebo_ardrone_empty_world.launch b/launch/gazebo_ardrone_empty_world.launch
index 395e70b006..d04991f19c 100644
--- a/launch/gazebo_ardrone_empty_world.launch
+++ b/launch/gazebo_ardrone_empty_world.launch
@@ -1,6 +1,6 @@
-
+
diff --git a/launch/gazebo_ardrone_house_world.launch b/launch/gazebo_ardrone_house_world.launch
index f43c16b509..d1bb2043aa 100644
--- a/launch/gazebo_ardrone_house_world.launch
+++ b/launch/gazebo_ardrone_house_world.launch
@@ -1,6 +1,6 @@
-
+
diff --git a/launch/gazebo_iris_empty_world.launch b/launch/gazebo_iris_empty_world.launch
index 833aaf07aa..d69b7d0069 100644
--- a/launch/gazebo_iris_empty_world.launch
+++ b/launch/gazebo_iris_empty_world.launch
@@ -1,6 +1,6 @@
-
+
diff --git a/launch/gazebo_iris_house_world.launch b/launch/gazebo_iris_house_world.launch
index bfdf9fe311..2e88e157c9 100644
--- a/launch/gazebo_iris_house_world.launch
+++ b/launch/gazebo_iris_house_world.launch
@@ -1,6 +1,6 @@
-
+
diff --git a/launch/gazebo_iris_outdoor_world.launch b/launch/gazebo_iris_outdoor_world.launch
index c2975a050d..a1df06496b 100644
--- a/launch/gazebo_iris_outdoor_world.launch
+++ b/launch/gazebo_iris_outdoor_world.launch
@@ -1,6 +1,6 @@
-
+