diff --git a/main.lua b/main.lua
index f8b3343..4df75a3 100644
--- a/main.lua
+++ b/main.lua
@@ -663,6 +663,11 @@ function SetThrusterPower(thruster, power)
     if thruster.type == "rotator" then
         thruster.power = power
         local actualPower = 0
+        if thruster.transmission == nil then
+            print("ERROR: SetThrusterPower called with nil transmission for rotator thruster.")
+            print("Thruster: "..thruster.name)
+            return
+        end
         if peripheral.getType(peripheral.wrap(thruster.transmission)) == "Create_RotationSpeedController" then
             if (math.ceil(power*256) - power*256 <= 0.5) then
                 actualPower = math.ceil(power*256)