diff --git a/libraries/AP_HAL/RCOutput.h b/libraries/AP_HAL/RCOutput.h
index af40f20f25..d08533c1bd 100644
--- a/libraries/AP_HAL/RCOutput.h
+++ b/libraries/AP_HAL/RCOutput.h
@@ -60,6 +60,13 @@ public:
      */
     virtual void     set_failsafe_pwm(uint32_t chmask, uint16_t period_us) {}
 
+    /*
+      force the safety switch on, disabling PWM output from the IO board
+      return false (indicating failure) by default so that boards with no safety switch
+      do not need to implement this method
+     */
+    virtual bool     force_safety_on(void) { return false; }
+
     /*
       force the safety switch off, enabling PWM output from the IO board
      */