diff --git a/libraries/AC_AttitudeControl/AC_PosControl.cpp b/libraries/AC_AttitudeControl/AC_PosControl.cpp
index af56b501266e6..5d42d08f624b0 100644
--- a/libraries/AC_AttitudeControl/AC_PosControl.cpp
+++ b/libraries/AC_AttitudeControl/AC_PosControl.cpp
@@ -806,7 +806,7 @@ void AC_PosControl::init_z()
 ///     The vel is projected forwards in time based on a time step of dt and acceleration accel.
 ///     The function takes the current position, velocity, and acceleration and calculates the required jerk limited adjustment to the acceleration for the next time dt.
 ///     The function alters the vel to be the kinematic path based on accel
-void AC_PosControl::input_accel_z(const float accel)
+void AC_PosControl::input_accel_z(float accel)
 {
     // calculated increased maximum acceleration if over speed
     float accel_z_cmss = _accel_max_z_cmss;
@@ -827,7 +827,7 @@ void AC_PosControl::input_accel_z(const float accel)
 ///     The function takes the current position, velocity, and acceleration and calculates the required jerk limited adjustment to the acceleration for the next time dt.
 ///     The kinematic path is constrained by the maximum acceleration and jerk set using the function set_max_speed_accel_z.
 ///     The parameter limit_output specifies if the velocity and acceleration limits are applied to the sum of commanded and correction values or just correction.
-void AC_PosControl::input_vel_accel_z(float &vel, const float accel, bool ignore_descent_limit, bool limit_output)
+void AC_PosControl::input_vel_accel_z(float &vel, float accel, bool ignore_descent_limit, bool limit_output)
 {
     if (ignore_descent_limit) {
         // turn off limits in the negative z direction
@@ -857,7 +857,7 @@ void AC_PosControl::input_vel_accel_z(float &vel, const float accel, bool ignore
 /// set_pos_target_z_from_climb_rate_cm - adjusts target up or down using a commanded climb rate in cm/s
 ///     using the default position control kinematic path.
 ///     The zero target altitude is varied to follow pos_offset_z
-void AC_PosControl::set_pos_target_z_from_climb_rate_cm(const float vel)
+void AC_PosControl::set_pos_target_z_from_climb_rate_cm(float vel)
 {
     // remove terrain offsets for flat earth assumption
     _pos_target.z -= _pos_offset_z;
@@ -879,10 +879,9 @@ void AC_PosControl::set_pos_target_z_from_climb_rate_cm(const float vel)
 /// land_at_climb_rate_cm - adjusts target up or down using a commanded climb rate in cm/s
 ///     using the default position control kinematic path.
 ///     ignore_descent_limit turns off output saturation handling to aid in landing detection. ignore_descent_limit should be true unless landing.
-void AC_PosControl::land_at_climb_rate_cm(const float vel, bool ignore_descent_limit)
+void AC_PosControl::land_at_climb_rate_cm(float vel, bool ignore_descent_limit)
 {
-    float vel_temp = vel;
-    input_vel_accel_z(vel_temp, 0, ignore_descent_limit);
+    input_vel_accel_z(vel, 0, ignore_descent_limit);
 }
 
 /// input_pos_vel_accel_z - calculate a jerk limited path from the current position, velocity and acceleration to an input position velocity and acceleration.
@@ -890,7 +889,7 @@ void AC_PosControl::land_at_climb_rate_cm(const float vel, bool ignore_descent_l
 ///     The function takes the current position, velocity, and acceleration and calculates the required jerk limited adjustment to the acceleration for the next time dt.
 ///     The function alters the pos and vel to be the kinematic path based on accel
 ///     The parameter limit_output specifies if the velocity and acceleration limits are applied to the sum of commanded and correction values or just correction.
-void AC_PosControl::input_pos_vel_accel_z(float &pos, float &vel, const float accel, bool limit_output)
+void AC_PosControl::input_pos_vel_accel_z(float &pos, float &vel, float accel, bool limit_output)
 {
     // calculated increased maximum acceleration if over speed
     float accel_z_cmss = _accel_max_z_cmss;
@@ -917,11 +916,10 @@ void AC_PosControl::input_pos_vel_accel_z(float &pos, float &vel, const float ac
 
 /// set_alt_target_with_slew - adjusts target up or down using a commanded altitude in cm
 ///     using the default position control kinematic path.
-void AC_PosControl::set_alt_target_with_slew(const float& pos)
+void AC_PosControl::set_alt_target_with_slew(float pos)
 {
-    float posf = pos;
     float zero = 0;
-    input_pos_vel_accel_z(posf, zero, 0);
+    input_pos_vel_accel_z(pos, zero, 0);
 }
 
 /// update_pos_offset_z - updates the vertical offsets used by terrain following
diff --git a/libraries/AC_AttitudeControl/AC_PosControl.h b/libraries/AC_AttitudeControl/AC_PosControl.h
index c4cab730ae042..53c69ec33aa11 100644
--- a/libraries/AC_AttitudeControl/AC_PosControl.h
+++ b/libraries/AC_AttitudeControl/AC_PosControl.h
@@ -187,24 +187,24 @@ class AC_PosControl
     /// input_accel_z - calculate a jerk limited path from the current position, velocity and acceleration to an input acceleration.
     ///     The function takes the current position, velocity, and acceleration and calculates the required jerk limited adjustment to the acceleration for the next time dt.
     ///     The kinematic path is constrained by the maximum acceleration and jerk set using the function set_max_speed_accel_z.
-    virtual void input_accel_z(const float accel);
+    virtual void input_accel_z(float accel);
 
     /// input_vel_accel_z - calculate a jerk limited path from the current position, velocity and acceleration to an input velocity and acceleration.
     ///     The function takes the current position, velocity, and acceleration and calculates the required jerk limited adjustment to the acceleration for the next time dt.
     ///     The kinematic path is constrained by the maximum acceleration and jerk set using the function set_max_speed_accel_z.
     ///     The function alters the vel to be the kinematic path based on accel
     ///     The parameter limit_output specifies if the velocity and acceleration limits are applied to the sum of commanded and correction values or just correction.
-    virtual void input_vel_accel_z(float &vel, const float accel, bool ignore_descent_limit, bool limit_output = true);
+    virtual void input_vel_accel_z(float &vel, float accel, bool ignore_descent_limit, bool limit_output = true);
 
     /// set_pos_target_z_from_climb_rate_cm - adjusts target up or down using a commanded climb rate in cm/s
     ///     using the default position control kinematic path.
     ///     The zero target altitude is varied to follow pos_offset_z
-    void set_pos_target_z_from_climb_rate_cm(const float vel);
+    void set_pos_target_z_from_climb_rate_cm(float vel);
 
     /// land_at_climb_rate_cm - adjusts target up or down using a commanded climb rate in cm/s
     ///     using the default position control kinematic path.
     ///     ignore_descent_limit turns off output saturation handling to aid in landing detection. ignore_descent_limit should be true unless landing.
-    void land_at_climb_rate_cm(const float vel, bool ignore_descent_limit);
+    void land_at_climb_rate_cm(float vel, bool ignore_descent_limit);
 
     /// input_pos_vel_accel_z - calculate a jerk limited path from the current position, velocity and acceleration to an input position velocity and acceleration.
     ///     The function takes the current position, velocity, and acceleration and calculates the required jerk limited adjustment to the acceleration for the next time dt.
@@ -214,7 +214,7 @@ class AC_PosControl
 
     /// set_alt_target_with_slew - adjusts target up or down using a commanded altitude in cm
     ///     using the default position control kinematic path.
-    void set_alt_target_with_slew(const float& pos);
+    void set_alt_target_with_slew(float pos);
 
     /// update_pos_offset_z - updates the vertical offsets used by terrain following
     void update_pos_offset_z(float pos_offset);