China's relaxation of COVID policies is sparking a recovery in the world's largest aviation market. China's "big three" airlines have resumed 136 international flights since the start of December. While China's borders remain closed to tourists, the airlines said there is strong demand from students, business travelers and others with long-term visas. Guangzhou Baiyun international airport, which recorded the largest passenger turnover in China last year, expects a sharp increase in international flights throughout the winter and into the spring of 2023.