diff --git a/src/main.rs b/src/main.rs
index dfd4953..bed994f 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -224,11 +224,11 @@ fn main() {
         let heli_tail_rotor_vao = unsafe { create_vao(&helicopter.tail_rotor.vertices, &helicopter.tail_rotor.normals, &helicopter.tail_rotor.colors, &helicopter.tail_rotor.indices) };
 
         // Scene Graph setup
-        let root_node    = SceneNode::new();
-        let terrain_node = SceneNode::from_vao(terrain_vao, terrain_mesh.index_count);
+        let mut root_node = SceneNode::new();
+        let mut terrain_node = SceneNode::from_vao(terrain_vao, terrain_mesh.index_count);
         root_node.add_child(&*terrain_node);
 
-        let heli_root       = SceneNode::new();
+        let mut heli_root = SceneNode::new();
         let body_node       = SceneNode::from_vao(heli_body_vao, helicopter.body.index_count);
         let door_node       = SceneNode::from_vao(heli_door_vao, helicopter.door.index_count);
         let main_rotor_node = SceneNode::from_vao(heli_main_rotor_vao, helicopter.main_rotor.index_count);