diff --git a/main.lua b/main.lua
index 15c2073..cb26784 100644
--- a/main.lua
+++ b/main.lua
@@ -302,11 +302,17 @@ local function checkIfThrusterIsIndexed()
     local unindexedThrusters = {}
 
     for _, v in ipairs(ThrusterTypes) do
-        table.insert(thrusters, peripheral.find(v))
+        local thrustersList = peripheral.find(v)
+        if thrustersList then
+            table.insert(thrusters, peripheral.find(v))
+        end
     end
 
     for _, v in ipairs(PropellerTypes) do
-        table.insert(thrusters, peripheral.find(v))
+        local thrustersList = peripheral.find(v)
+        if thrustersList then
+            table.insert(thrusters, peripheral.find(v))
+        end
     end
 
     for _, v in ipairs(thrusters) do