EKF: Don't use GPS to set position noise when not using GPS

EKF/vel_pos_fusion.cpp

@@ -89,8 +89,13 @@ void Ekf::fuseVelPosHeight()
 
 		// observation variance - user parameter defined
 		// if we are in flight and not using GPS, then use a specific parameter
-		if (!_control_status.flags.gps && _control_status.flags.in_air) {
-			R[3] = fmaxf(_params.pos_noaid_noise, 0.5f);
+		if (!_control_status.flags.gps) {
+			if (_control_status.flags.in_air) {
+				R[3] = fmaxf(_params.pos_noaid_noise, _params.gps_pos_noise);
+
+			} else {
+				R[3] = _params.gps_pos_noise;
+			}
 
 		} else {
 			float lower_limit = fmaxf(_params.gps_pos_noise, 0.01f);
@@ -258,5 +263,4 @@ void Ekf::fuseVelPosHeight()
 		makeSymmetrical();
 		limitCov();
 	}
-
 }