diff --git a/libraries/APM_PI/APM_PI.h b/libraries/APM_PI/APM_PI.h
index cc8f8721bc..b227d379d0 100644
--- a/libraries/APM_PI/APM_PI.h
+++ b/libraries/APM_PI/APM_PI.h
@@ -14,83 +14,99 @@
 class APM_PI {
 public:
 
-	/// Constructor for PI that saves its settings to EEPROM
-	///
-	/// @note	PI must be named to avoid either multiple parameters with the
-	///			same name, or an overly complex constructor.
-	///
-	/// @param  initial_p       Initial value for the P term.
+    /// Constructor for PI that saves its settings to EEPROM
+    ///
+    /// @note	PI must be named to avoid either multiple parameters with the
+    ///			same name, or an overly complex constructor.
+    ///
+    /// @param  initial_p       Initial value for the P term.
     /// @param  initial_i       Initial value for the I term.
     /// @param  initial_imax    Initial value for the imax term.4
-	///
-	APM_PI(const float &initial_p = 0.0,
-		   const float &initial_i = 0.0,
-		   const int16_t &initial_imax = 0.0)
-	{
-		_kp = initial_p;
-		_ki = initial_i;
-		_imax = initial_imax;
-	}
-
-	/// Iterate the PI, return the new control value
-	///
-	/// Positive error produces positive output.
-	///
-	/// @param error	The measured error value
-	/// @param dt		The time delta in milliseconds (note
-	///					that update interval cannot be more
-	///					than 65.535 seconds due to limited range
-	///					of the data type).
-	/// @param scaler	An arbitrary scale factor
-	///
-	/// @returns		The updated control output.
-	///
-	//long 	get_pi(int32_t error, float	 dt);
-	int32_t get_pi(int32_t error, float dt);
-	int32_t get_p(int32_t error);
-	int32_t get_i(int32_t error, float dt);
-
-
-	/// Reset the PI integrator
-	///
-	void	reset_I();
-
-	/// Load gain properties
-	///
-	void 	load_gains();
-
-	/// Save gain properties
-	///
-	void 	save_gains();
-
-	/// @name	parameter accessors
-	//@{
-
-	/// Overload the function call operator to permit relatively easy initialisation
-	void operator() (const float p,
-	                 const float i,
-	                 const int16_t imaxval) {
-		_kp = p; _ki = i; _imax = imaxval;
-	}
-
-	float	kP() const				{ return _kp.get(); }
-	float	kI() const 				{ return _ki.get(); }
-	int16_t	imax() const			{ return _imax.get(); }
-
-	void	kP(const float v)		{ _kp.set(v); }
-	void	kI(const float v)		{ _ki.set(v); }
-	void	imax(const int16_t v)	{ _imax.set(abs(v)); }
-	float	get_integrator() const	{ return _integrator; }
-	void	set_integrator(float i)	{ _integrator = i; }
-
-    static const struct AP_Param::GroupInfo var_info[];
+    ///
+    APM_PI(const float &    initial_p = 0.0,
+           const float &    initial_i = 0.0,
+           const int16_t &  initial_imax = 0.0)
+    {
+        _kp = initial_p;
+        _ki = initial_i;
+        _imax = initial_imax;
+    }
+
+    /// Iterate the PI, return the new control value
+    ///
+    /// Positive error produces positive output.
+    ///
+    /// @param error	The measured error value
+    /// @param dt		The time delta in milliseconds (note
+    ///					that update interval cannot be more
+    ///					than 65.535 seconds due to limited range
+    ///					of the data type).
+    /// @param scaler	An arbitrary scale factor
+    ///
+    /// @returns		The updated control output.
+    ///
+    //long  get_pi(int32_t error, float	 dt);
+    int32_t         get_pi(int32_t error, float dt);
+    int32_t         get_p(int32_t error);
+    int32_t         get_i(int32_t error, float dt);
+
+
+    /// Reset the PI integrator
+    ///
+    void        reset_I();
+
+    /// Load gain properties
+    ///
+    void        load_gains();
+
+    /// Save gain properties
+    ///
+    void        save_gains();
+
+    /// @name	parameter accessors
+    //@{
+
+    /// Overload the function call operator to permit relatively easy initialisation
+    void operator        () (const float    p,
+                             const float    i,
+                             const int16_t  imaxval) {
+        _kp = p; _ki = i; _imax = imaxval;
+    }
+
+    float           kP() const {
+        return _kp.get();
+    }
+    float           kI() const {
+        return _ki.get();
+    }
+    int16_t         imax() const {
+        return _imax.get();
+    }
+
+    void            kP(const float v)               {
+        _kp.set(v);
+    }
+    void            kI(const float v)               {
+        _ki.set(v);
+    }
+    void            imax(const int16_t v)   {
+        _imax.set(abs(v));
+    }
+    float           get_integrator() const {
+        return _integrator;
+    }
+    void            set_integrator(float i) {
+        _integrator = i;
+    }
+
+    static const struct AP_Param::GroupInfo        var_info[];
 
 private:
-	AP_Float			_kp;
-	AP_Float			_ki;
-	AP_Int16			_imax;
+    AP_Float        _kp;
+    AP_Float        _ki;
+    AP_Int16        _imax;
 
-	float				_integrator;		///< integrator value
+    float           _integrator;                                ///< integrator value
 };
 
 #endif