diff --git a/libraries/AP_Vehicle/AP_Vehicle.h b/libraries/AP_Vehicle/AP_Vehicle.h
index 4e8d9fc732..24ab21c23d 100644
--- a/libraries/AP_Vehicle/AP_Vehicle.h
+++ b/libraries/AP_Vehicle/AP_Vehicle.h
@@ -221,6 +221,9 @@ public:
     // set turn rate in deg/sec and speed in meters/sec (for use by scripting with Rover)
     virtual bool set_desired_turn_rate_and_speed(float turn_rate, float speed) { return false; }
 
+   // set auto mode speed in meters/sec (for use by scripting with Copter/Rover)
+    virtual bool set_desired_speed(float speed) { return false; }
+
     // support for NAV_SCRIPT_TIME mission command
     virtual bool nav_script_time(uint16_t &id, uint8_t &cmd, float &arg1, float &arg2) { return false; }
     virtual void nav_script_time_done(uint16_t id) {}