diff --git a/Client/multiplayer_sa/CMultiplayerSA.cpp b/Client/multiplayer_sa/CMultiplayerSA.cpp
index 28d5b1f551c..1b21f79a238 100644
--- a/Client/multiplayer_sa/CMultiplayerSA.cpp
+++ b/Client/multiplayer_sa/CMultiplayerSA.cpp
@@ -1569,6 +1569,10 @@ void CMultiplayerSA::InitHooks()
     // Fix invisible vehicle windows when lights are on (#2936)
     MemPut<BYTE>(0x6E1425, 1);
 
+    // Allow alpha change for helicopter rotor (#523)
+    MemSet((void*)0x6C444B, 0x90, 6);
+    MemSet((void*)0x6C4453, 0x90, 0x68);
+    
     InitHooks_CrashFixHacks();
 
     // Init our 1.3 hooks.