Tan Son Nhat Airport was one of the three busiest in the world in the late 1960s. The runways are still lined with lichen-covered, mortar-proof aircraft-retaining walls, hangars and other military structures. You must reconfirm all reservations for flights out of the country.
Nearly all domestic flights are operated by Vietnam Airlines. Pacific Airlines also flies the HCMC-Hanoi and HCMC-Danang route.
Tan Son Nhat Airport is 7km northwest of central HCMC. Metered taxis are your best bet and cost around 60,000d (US$4) between the airport and the city centre. You'll be enthusiastically greeted by a group of taxi drivers after you exit the terminal; most are OK, but make sure that the driver agrees to use the meter and it is switched on after you get in the car. The final fare to central HCMC shouldn't go much over 60,000d.
Be aware that taxi drivers will probably recommend a 'good and cheap' hotel, and deliver you to a hotel for a commission; if you don't know where you're going, this is not a bad system per se. Problems may arise, however, when you ask a taxi driver to take you to a place that doesn't pay commission. The driver may tell you the hotel is closed, burned down, is dirty and dangerous, or anything to steer you somewhere else.
If you're travelling solo and without much baggage, a motorbike taxi is an option for getting to/from the airport. Drivers hang out near the airport car park and typically ask around US$3 to go to the city centre. If you take a motorbike taxi to Tan Son Nhat, you may have to walk the short distance from the airport gate to the terminal. Private cars can bring you into the airport, but must drop you off at the domestic terminal, only a minute's walk from the international terminal.
To get to the airport you can call a taxi. Some cafes in the Pham Ngu Lao area do runs to the airport - these places even have sign-up sheets where you can book share-taxis for US$2 per person.
Most economical is the air-conditioned airport bus, No 152, going to and from the airport. Buses leave the airport approximately every 15 minutes, stopping briefly at both the internal lal and domestic terminals before heauing downtown. They then make regular stops along De Tham street (Pham Ngu Lao area) and international hotels along Dong Khoi street, such as the Caravelle and the Majestic. Buses are labelled in English, but you might also look for the words 'Xe Buyt! San Bay'.