Qantas () (or Coentas) is the Australian flag carrier which is Australias largest airline. The airlines intimate name is Qantas - flying kangaroo. Qantas is a founding member of the Oneworld airlines Alliance.Qantas was founded in 1920 and began formal operations in March 1921. It is now the third oldest airline in the world, after KLM and Avianca Airlines.< < > Qantas is headquartered at Sydney Airport. A portion of the shares of Qantas airlines are exchanged on the Australian Stock Exchange.