Atlas Air (5Y) is a charter and cargo airline that was founded in 1992. The airline operates a charter on behalf of the United States-Africa Energy Association (USAEA) and flies three times a week between Houston's George Bush Intercontinental Airport (IAH) and Quatro de Fevereiro Airport (LAD) in Luanda, Angola. These flights, known as the Houston Express, are served by two Boeing 747-400 aircraft that each hold 189 passengers with a three-cabin configuration. Seat assignments are usually made upon checking in at the airport. Economy Class passengers may check up to two pieces of luggage, Business Class passengers can check no more than three bags and First Class passengers can check up to four pieces of luggage. Each passenger may carry on one piece of luggage and one personal item.