diff --git a/commander.html b/commander.html
index cf0f16c..3c6a085 100644
--- a/commander.html
+++ b/commander.html
@@ -230,16 +230,19 @@
             let lockBtn = document.createElement("div");
             lockBtn.className = "btn";
             lockBtn.innerHTML = lockIcon;
+            lockBtn.ariaLabel = "lock";
             lockBtn.addEventListener('click', lockBoat);
             boatCells[3].append(lockBtn);
             let freeBtn = document.createElement("div");
             freeBtn.className = "btn";
             freeBtn.innerHTML = freeIcon;
+            lockBtn.ariaLabel = "free";
             freeBtn.addEventListener('click', freeBoat);
             boatCells[3].append(freeBtn);
             let logBtn = document.createElement("div");
             logBtn.className = "btn";
             logBtn.innerHTML = logIcon;
+            lockBtn.ariaLabel = "view log";
             logBtn.addEventListener('click', getBoatLog);
             boatCells[3].append(logBtn);
             for (cell in boatCells)
diff --git a/ground-station.py b/ground-station.py
index c510946..bf275d5 100644
--- a/ground-station.py
+++ b/ground-station.py
@@ -78,6 +78,7 @@ async def free_boat(boat):
     for client in Clients:
         if client["boat"] is not None and client["boat"]['id'] == boat:
             client["boat"] = None
+            await client['ws'].send("FAIL")
             break
     for b in Boats:
         if b['id'] == boat and b['state'] != BOAT_STATE_TERMINATED:
@@ -89,6 +90,7 @@ async def lock_boat(boat):
     for client in Clients:
         if client["boat"] is not None and client["boat"]['id'] == boat:
             client["boat"] = None
+            await client['ws'].send("FAIL")
             break
     for b in Boats:
         if b['id'] == boat and b['state'] != BOAT_STATE_TERMINATED:
@@ -116,11 +118,11 @@ async def kick_client(clientId):
     """kick a client"""
     for client in Clients:
         if client['id'] == client and client['state'] == "terminated":
-            if client['state'] is not None:
+            if client['boat'] is not None:
                 client['boat']['state'] = BOAT_STATE_AVAILABLE
                 client['boat'] = None
-                client['state'] = "kicked"
-                await client['ws'].send("FAIL")
+            client['state'] = "kicked"
+            await client['ws'].send("FAIL")
             return
 
 
@@ -151,6 +153,7 @@ async def on_message(message, client):
         elif data[1] == "d":
             if client['boat'] is None:
                 print("WARN: controll cmd (" + client['id'] + ") to None: " + data[2])
+                await client['ws'].send("FAIL")
             elif client['boat']['lastMsg'] + BOAT_DATA_INTERVAL_MAX < datetime.timestamp(datetime.now()):
                 # print("INFO: controll cmd (" + client['id'] + ") to " + client['boat']['name'] + ": " + data[2])
                 await sendToBoat(client['boat'], "d:" + data[2] + "\n")
diff --git a/index.html b/index.html
index 4702a2f..d9564cb 100644
--- a/index.html
+++ b/index.html
@@ -66,14 +66,23 @@
                             let el = document.createElement("div");
                             el.style.textAlign = "center";
                             el.style.borderRadius = "10px";
-                            el.style.backgroundColor = "#242495";
                             el.style.padding = "10px";
                             el.style.margin = "5px 25%";
-                            el.style.color = "white";
-                            el.style.cursor = "pointer";
+                            if (boat[2] == 'available')
+                            {
+                                el.style.backgroundColor = "#242495";
+                                el.style.color = "white";
+                                el.style.cursor = "pointer";
+                                el.addEventListener('click', selectBoat);
+                            }
+                            else
+                            {
+                                el.style.backgroundColor = "#CCCCCC";
+                                el.style.color = "black";
+                                el.style.cursor = "not-allowed";
+                            }
                             el.id = "boat" + boat[0];
                             el.innerHTML = boat[1];
-                            el.addEventListener('click', selectBoat);
                             boatListEl.appendChild(el);
                         }
                     }
@@ -88,6 +97,7 @@
             {
                 console.error("ground station send FAIL");
                 connection.send(clientId + ';boats');
+                state = "connected";
             }
             else
             {