It will takes about half an hour to get to the Hongqiao airport from the downtown. But traffic jam happens frequently, if so, it will cost about 1 hour. For the domestic flights, you’d better arrive at the airport about 2 hours before the departure time to make sure everything goes smoothly. It will cost about CNY50.00 net from the downtown to the Hongqiao Airport. But it depends on the traffic status. Maybe it will be a little bit hard to get taxi at a hot place during the hot hour. It depends. You may consult the hotel staff before departure.