diff --git a/classes/Authentication.php b/classes/Authentication.php
index e6fe1d3..f5a2624 100644
--- a/classes/Authentication.php
+++ b/classes/Authentication.php
@@ -1,6 +1,7 @@
 <?php namespace GermanAirlinesVa\Graphql\Classes;
 
 use Closure;
+use Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException;
 
 class Authentication
 {
@@ -13,11 +14,11 @@ class Authentication
    */
   public function handle($request, Closure $next)
   {
-    if ($request->input('gql_session') === 'SUPER_SECRET_TOKEN') {
-      return "false";
+    if ($request->header('Gql-Session') === 'SUPER_SECRET_KEY_HEADER') {
+      return "";
     }
     else {
-      return "true";
+      throw new AccessDeniedHttpException;
     }
 
     return $next($request);
diff --git a/graphs/fleet.htm b/graphs/fleet.htm
index f9c74f7..bd76492 100644
--- a/graphs/fleet.htm
+++ b/graphs/fleet.htm
@@ -23,6 +23,7 @@ extend type Mutation {
 }
 
 type Aircraft {
+  id: ID!
   aircraft_type_id: ID!
   home_airport_id: ID!
   name: String!