diff --git a/libraries/AP_HAL_ChibiOS/hwdef/VRUBrain-v51/hwdef.dat b/libraries/AP_HAL_ChibiOS/hwdef/VRUBrain-v51/hwdef.dat
index 17842a5424..b9628d6738 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/VRUBrain-v51/hwdef.dat
+++ b/libraries/AP_HAL_ChibiOS/hwdef/VRUBrain-v51/hwdef.dat
@@ -174,3 +174,11 @@ define STM32_PWM_USE_ADVANCED TRUE
 # 12 PWM available by default
 define BOARD_PWM_COUNT_DEFAULT 14
 
+# save some flash
+define GENERATOR_ENABLED 0
+define AC_OAPATHPLANNER_ENABLED 0
+define PRECISION_LANDING 0
+define HAL_BARO_WIND_COMP_ENABLED 0
+define HAL_RUNCAM_ENABLED 0
+define HAL_SPEKTRUM_TELEM_ENABLED 0
+define HAL_SOARING_ENABLED 0