diff --git a/libraries/AP_Motors/AP_MotorsHeli.cpp b/libraries/AP_Motors/AP_MotorsHeli.cpp
index 7aca12806a..ddb7846de4 100644
--- a/libraries/AP_Motors/AP_MotorsHeli.cpp
+++ b/libraries/AP_Motors/AP_MotorsHeli.cpp
@@ -144,6 +144,7 @@ const AP_Param::GroupInfo AP_MotorsHeli::var_info[] PROGMEM = {
     // @DisplayName: Collective-Yaw Mixing
     // @Description: Feed-forward compensation to automatically add rudder input when collective pitch is increased. Can be positive or negative depending on mechanics.
     // @Range: -10 10
+    // @Increment: 0.1
     AP_GROUPINFO("COLYAW",  14,     AP_MotorsHeli,  _collective_yaw_effect, 0),
 
     // @Param: GOV_SETPOINT
@@ -606,6 +607,8 @@ void AP_MotorsHeli::move_swash(int16_t roll_out, int16_t pitch_out, int16_t coll
         // the feed-forward is not required when the motor is shut down and not creating torque
         // also not required if we are using external gyro
         if ((_rotor_desired > 0) && _tail_type != AP_MOTORS_HELI_TAILTYPE_SERVO_EXTGYRO) {
+            // sanity check collective_yaw_effect
+            _collective_yaw_effect = constrain_float(_collective_yaw_effect, -AP_MOTOR_HELI_COLYAW_RANGE, AP_MOTOR_HELI_COLYAW_RANGE);
             yaw_offset = _collective_yaw_effect * abs(_collective_out - _collective_mid_pwm);
         }
     }
diff --git a/libraries/AP_Motors/AP_MotorsHeli.h b/libraries/AP_Motors/AP_MotorsHeli.h
index c56645da21..01ce119370 100644
--- a/libraries/AP_Motors/AP_MotorsHeli.h
+++ b/libraries/AP_Motors/AP_MotorsHeli.h
@@ -59,6 +59,8 @@
 // minimum outputs for direct drive motors
 #define AP_MOTOR_HELI_DDTAIL_DEFAULT       500
 
+// COLYAW parameter min and max values
+#define AP_MOTOR_HELI_COLYAW_RANGE             10.0f
 
 // main rotor speed control types (ch8 out)
 #define AP_MOTORS_HELI_RSC_MODE_NONE            0       // main rotor ESC is directly connected to receiver, pilot controls ESC speed through transmitter directly
@@ -275,7 +277,7 @@ private:
     AP_Int16        _ext_gyro_gain;             // PWM sent to external gyro on ch7 when tail type is Servo w/ ExtGyro
     AP_Int8         _servo_manual;              // Pass radio inputs directly to servos during set-up through mission planner
     AP_Int16        _phase_angle;               // Phase angle correction for rotor head.  If pitching the swash forward induces a roll, this can be correct the problem
-    AP_Int16        _collective_yaw_effect;     // Feed-forward compensation to automatically add rudder input when collective pitch is increased. Can be positive or negative depending on mechanics.    
+    AP_Float        _collective_yaw_effect;     // Feed-forward compensation to automatically add rudder input when collective pitch is increased. Can be positive or negative depending on mechanics.
     AP_Int16        _rsc_setpoint;              // rotor speed when RSC mode is set to is enabledv
     AP_Int8         _rsc_mode;                  // Which main rotor ESC control mode is active
     AP_Int8         _rsc_ramp_time;             // Time in seconds for the output to the main rotor's ESC to reach full speed