diff --git a/ArduCopterMega/navigation.pde b/ArduCopterMega/navigation.pde
index 52b912ccee..1af23e1bf1 100644
--- a/ArduCopterMega/navigation.pde
+++ b/ArduCopterMega/navigation.pde
@@ -41,9 +41,12 @@ void navigate()
 	update_navigation();
 }
 
-#define DIST_ERROR_MAX 3000
+#define DIST_ERROR_MAX 1800
 void calc_nav()
 {
+	Vector2f yawvector;
+	long long_error, lat_error;
+
 	/*
 	Becuase we are using lat and lon to do our distance errors here's a quick chart:
 	100 	= 1m
@@ -51,25 +54,33 @@ void calc_nav()
 	3000 	= 33m
 	10000 	= 111m
 	pitch_max = 22° (2200)
-	*/
-	
-	Vector2f yawvector;
-	Matrix3f temp = dcm.get_dcm_matrix();
+	*/	
 
-	yawvector.x 	= temp.a.x;
-	yawvector.y 	= temp.b.x;
+	Matrix3f temp = dcm.get_dcm_matrix();
+	yawvector.x 	= temp.a.x; // sin
+	yawvector.y 	= temp.b.x;	// cos
 	yawvector.normalize();
 	
+	yawvector.y = -yawvector.y;
+	//cos = 
+	long_error	= (float)(next_WP.lng - current_loc.lng) * scaleLongDown;
+	lat_error	= next_WP.lat - current_loc.lat;
+	
+	long_error	= constrain(long_error, -DIST_ERROR_MAX, DIST_ERROR_MAX); // +- 20m max error
+	lat_error	= constrain(lat_error,  -DIST_ERROR_MAX, DIST_ERROR_MAX); // +- 20m max error
+	
 	// ROLL
-	nav_lon = pid_nav_lon.get_pid((long)((float)(next_WP.lng - GPS.longitude) * scaleLongDown), dTnav, 1.0);
-	nav_lon = constrain(nav_lon, -DIST_ERROR_MAX, DIST_ERROR_MAX); // Limit max command
+	nav_lon		= long_error * pid_nav_lon.kP();
+	//nav_lon	= pid_nav_lon.get_pid(long_error, dTnav2, 1.0);
+	//nav_lon 	= constrain(nav_lon, -DIST_ERROR_MAX, DIST_ERROR_MAX); // Limit max command
 
 	// PITCH
-	nav_lat = pid_nav_lat.get_pid(next_WP.lat - GPS.latitude, dTnav, 1.0);
-	nav_lat = constrain(nav_lat, -DIST_ERROR_MAX, DIST_ERROR_MAX); // Limit max command
+	//nav_lat 	= pid_nav_lat.get_pid(lat_error, dTnav2, 1.0);
+	nav_lat		= lat_error * pid_nav_lat.kP();
+	//nav_lat 	= constrain(nav_lat, -DIST_ERROR_MAX, DIST_ERROR_MAX); // Limit max command
 
-	// rotate the vector
-	nav_roll 	= (float)nav_lon * yawvector.x + (float)nav_lat * yawvector.y;
+	// rotate the vector				
+	nav_roll 	= (float)nav_lon * yawvector.x - (float)nav_lat * yawvector.y;
 	nav_pitch 	= (float)nav_lat * yawvector.x + (float)nav_lon * yawvector.y;
 	
 	//Serial.printf("vx %4.4f,vy %4.4f ", yawvector.x, yawvector.y);