diff --git a/radio/src/bootloader/boot.cpp b/radio/src/bootloader/boot.cpp
index 3a7a2bb5e..67210e8c6 100644
--- a/radio/src/bootloader/boot.cpp
+++ b/radio/src/bootloader/boot.cpp
@@ -137,6 +137,8 @@ UINT BlockCount;
 
 uint32_t memoryType;
 
+uint32_t unlocked = 0;
+
 #if defined(PCBSKY9X)
   extern int32_t EblockAddress;
 #endif
@@ -520,7 +522,6 @@ int main()
 #if defined(PCBTARANIS)
   // SD card detect pin
   sdInit();
-  unlockFlash();
   usbInit();
   usbStart();
 #endif
@@ -714,7 +715,12 @@ int main()
       else if (state == ST_FLASHING) {
         // commit to flashing
         lcd_putsLeft(4*FH, "\032Writing...");
-
+        
+        if (!unlocked && (memoryType == MEM_FLASH)) {
+          unlocked = 1;
+          unlockFlash();
+        }
+        
         int progress;
         if (memoryType == MEM_FLASH) {
           writeFlashBlock();
@@ -745,6 +751,10 @@ int main()
       }
 
       if (state == ST_FLASH_DONE) {
+        if (unlocked) {
+          lockFlash();
+          unlocked = 0;
+        }
         lcd_putsLeft(4*FH, "\024Writing Complete");
         if (event == EVT_KEY_FIRST(BOOT_KEY_EXIT) || event == EVT_KEY_BREAK(BOOT_KEY_MENU)) {
           state = ST_START;
diff --git a/radio/src/gui/menu_general.cpp b/radio/src/gui/menu_general.cpp
index 7341fef8a..35dfdc987 100644
--- a/radio/src/gui/menu_general.cpp
+++ b/radio/src/gui/menu_general.cpp
@@ -773,6 +773,11 @@ void flashBootloader(const char * filename)
     }
   }
 
+  if (unlocked) {
+    lockFlash();
+    unlocked = 0;
+  }
+
   f_close(&file);
 }
 #endif
diff --git a/radio/src/simpgmspace.cpp b/radio/src/simpgmspace.cpp
index eff6026b6..d22716f8a 100644
--- a/radio/src/simpgmspace.cpp
+++ b/radio/src/simpgmspace.cpp
@@ -674,6 +674,7 @@ void RCC_LSEConfig(uint8_t RCC_LSE) { }
 FlagStatus RCC_GetFlagStatus(uint8_t RCC_FLAG) { return RESET; }
 ErrorStatus RTC_WaitForSynchro(void) { return SUCCESS; }
 void unlockFlash() { }
+void lockFlash() { }
 void writeFlash(uint32_t *address, uint32_t *buffer) { SIMU_SLEEP(100); }
 uint32_t isBootloaderStart(const void *block) { return 1; }
 #endif
diff --git a/radio/src/targets/taranis/board_taranis.h b/radio/src/targets/taranis/board_taranis.h
index a66004edf..195dc3e3e 100644
--- a/radio/src/targets/taranis/board_taranis.h
+++ b/radio/src/targets/taranis/board_taranis.h
@@ -144,6 +144,7 @@ void delay_01us(uint16_t nb);
 // Flash Write driver
 #define FLASH_PAGESIZE 256
 void unlockFlash();
+void lockFlash();
 void writeFlash(uint32_t * address, uint32_t * buffer);
 uint32_t isFirmwareStart(const void * buffer);
 uint32_t isBootloaderStart(const void * buffer);
diff --git a/radio/src/targets/taranis/flash_driver.cpp b/radio/src/targets/taranis/flash_driver.cpp
index a57aac087..cca4f7e27 100644
--- a/radio/src/targets/taranis/flash_driver.cpp
+++ b/radio/src/targets/taranis/flash_driver.cpp
@@ -16,6 +16,12 @@ void unlockFlash()
   FLASH->KEYR = 0xCDEF89AB;
 }
 
+void lockFlash()
+{
+  while (!FLASH->SR & FLASH_SR_BSY);
+  FLASH->CR |= FLASH_CR_LOCK;
+}
+
 void waitFlashIdle()
 {
   while (FLASH->SR & FLASH_FLAG_BSY) {