diff --git a/EKF/EKFGSF_yaw.h b/EKF/EKFGSF_yaw.h
index 3b44101f18..07b8061ebc 100644
--- a/EKF/EKFGSF_yaw.h
+++ b/EKF/EKFGSF_yaw.h
@@ -60,25 +60,25 @@ private:
 
 	// Declarations used by the bank of N_MODELS_EKFGSF AHRS complementary filters
 
-	Vector3f _delta_ang;	// IMU delta angle (rad)
-	Vector3f _delta_vel;	// IMU delta velocity (m/s)
-	float _delta_ang_dt;	// _delta_ang integration time interval (sec)
-	float _delta_vel_dt;	// _delta_vel integration time interval (sec)
-	float _true_airspeed;	// true airspeed used for centripetal accel compensation (m/s)
+	Vector3f _delta_ang{};	// IMU delta angle (rad)
+	Vector3f _delta_vel{};	// IMU delta velocity (m/s)
+	float _delta_ang_dt{};	// _delta_ang integration time interval (sec)
+	float _delta_vel_dt{};	// _delta_vel integration time interval (sec)
+	float _true_airspeed{};	// true airspeed used for centripetal accel compensation (m/s)
 
 	struct _ahrs_ekf_gsf_struct{
-		Dcmf R;				// matrix that rotates a vector from body to earth frame
-		Vector3f gyro_bias;		// gyro bias learned and used by the quaternion calculation
-		bool aligned{false};		// true when AHRS has been aligned
-		float vel_NE[2] {};		// NE velocity vector from last GPS measurement (m/s)
-		bool fuse_gps = false;		// true when GPS should be fused on that frame
-		float accel_dt = 0;		// time step used when generating _simple_accel_FR data (sec)
-	};
-	_ahrs_ekf_gsf_struct _ahrs_ekf_gsf[N_MODELS_EKFGSF];
-	bool _ahrs_ekf_gsf_tilt_aligned = false;// true the initial tilt alignment has been calculated
-	float _ahrs_accel_fusion_gain;		// gain from accel vector tilt error to rate gyro correction used by AHRS calculation
-	Vector3f _ahrs_accel;			// low pass filtered body frame specific force vector used by AHRS calculation (m/s/s)
-	float _ahrs_accel_norm;			// length of _ahrs_accel specific force vector used by AHRS calculation (m/s/s)
+		Dcmf R;			// matrix that rotates a vector from body to earth frame
+		Vector3f gyro_bias;	// gyro bias learned and used by the quaternion calculation
+		bool aligned;		// true when AHRS has been aligned
+		float vel_NE[2];	// NE velocity vector from last GPS measurement (m/s)
+		bool fuse_gps;		// true when GPS should be fused on that frame
+		float accel_dt;		// time step used when generating _simple_accel_FR data (sec)
+	} _ahrs_ekf_gsf[N_MODELS_EKFGSF]{};
+
+	bool _ahrs_ekf_gsf_tilt_aligned{};	// true the initial tilt alignment has been calculated
+	float _ahrs_accel_fusion_gain{};	// gain from accel vector tilt error to rate gyro correction used by AHRS calculation
+	Vector3f _ahrs_accel{};			// low pass filtered body frame specific force vector used by AHRS calculation (m/s/s)
+	float _ahrs_accel_norm{};		// length of _ahrs_accel specific force vector used by AHRS calculation (m/s/s)
 
 	// calculate the gain from gravity vector misalingment to tilt correction to be used by all AHRS filters
 	float ahrsCalcAccelGain() const;
@@ -98,18 +98,18 @@ private:
 	// Declarations used by a bank of N_MODELS_EKFGSF EKFs
 
 	struct _ekf_gsf_struct{
-		matrix::Vector3f X; // Vel North (m/s),  Vel East (m/s), yaw (rad)s
-		matrix::SquareMatrix<float, 3> P; // covariance matrix
-		matrix::SquareMatrix<float, 2> S_inverse;  // inverse of the innovation covariance matrix
-		float S_det_inverse; // inverse of the innovation covariance matrix determinant
-		matrix::Vector2f innov; // Velocity N,E innovation (m/s)
-	};
-	_ekf_gsf_struct _ekf_gsf[N_MODELS_EKFGSF];
-	bool _vel_data_updated;  // true when velocity data has been updated
-	bool _run_ekf_gsf;       // true when operating condition is suitable for to run the GSF and EKF models and fuse velocity data
-	Vector2f _vel_NE;        // NE velocity observations (m/s)
-	float _vel_accuracy;     // 1-sigma accuracy of velocity observations (m/s)
-	bool _ekf_gsf_vel_fuse_started;	// true when the EKF's have started fusing velocity data and the prediction and update processing is active
+		matrix::Vector3f X; 				// Vel North (m/s),  Vel East (m/s), yaw (rad)s
+		matrix::SquareMatrix<float, 3> P; 		// covariance matrix
+		matrix::SquareMatrix<float, 2> S_inverse;	// inverse of the innovation covariance matrix
+		float S_det_inverse; 				// inverse of the innovation covariance matrix determinant
+		matrix::Vector2f innov; 			// Velocity N,E innovation (m/s)
+	} _ekf_gsf[N_MODELS_EKFGSF]{};
+
+	bool _vel_data_updated{};	// true when velocity data has been updated
+	bool _run_ekf_gsf{};		// true when operating condition is suitable for to run the GSF and EKF models and fuse velocity data
+	Vector2f _vel_NE{};        // NE velocity observations (m/s)
+	float _vel_accuracy{};     // 1-sigma accuracy of velocity observations (m/s)
+	bool _ekf_gsf_vel_fuse_started{}; // true when the EKF's have started fusing velocity data and the prediction and update processing is active
 
 	// initialise states and covariance data for the GSF and EKF filters
 	void initialiseEKFGSF();
@@ -133,9 +133,9 @@ private:
 
 	// Declarations used by the Gaussian Sum Filter (GSF) that combines the individual EKF yaw estimates
 
-	matrix::Vector<float, N_MODELS_EKFGSF> _model_weights;
-	float _gsf_yaw; 		// yaw estimate (rad)
-	float _gsf_yaw_variance; 	// variance of yaw estimate (rad^2)
+	matrix::Vector<float, N_MODELS_EKFGSF> _model_weights{};
+	float _gsf_yaw{}; 		// yaw estimate (rad)
+	float _gsf_yaw_variance{}; 	// variance of yaw estimate (rad^2)
 
 	// return the probability of the state estimate for the specified EKF assuming a gaussian error distribution
 	float gaussianDensity(const uint8_t model_index) const;