static constexpr float HDG_HOLD_DIST_NEXT =	3000.0f; // initial distance of waypoint in front of plane in heading hold mode
static constexpr float HDG_HOLD_REACHED_DIST =	1000.0f; // distance (plane to waypoint in front) at which waypoints are reset in heading hold mode
static constexpr float HDG_HOLD_SET_BACK_DIST = 100.0f; // distance by which previous waypoint is set behind the plane
	void		get_waypoint_heading_distance(float heading, position_setpoint_s &waypoint_prev, position_setpoint_s &waypoint_next, bool flag_init);