Star Dust (registration G-AGWH) was a British South American Airways (BSAA) Avro Lancastrian airliner which disappeared in mysterious circumstances on 2 August 1947 during a flight from Buenos Aires, Argentina to Santiago, Chile. A comprehensive search of a wide area (including what is now known to have been the crash site) discovered no wreckage, and the true fate of the aircraft and its passengers and crew remained a mystery for over fifty years. Speculation about the cause and nature of the disappearance of Star Dust included theories of international intrigue, intercorporate sabotage or abduction by aliens.
In the late 1990s, pieces of wreckage from the missing aircraft began to emerge from glacial ice in the Andes mountains near Santiago. It is now assumed that the crew became confused as to their exact location whilst flying at high altitudes through the (then poorly understood) jet stream. Mistakenly believing that they had already cleared the mountain tops before starting their descent, when in fact they were still behind cloud-covered peaks, Star Dust slammed into Mount Tupungato, killing all aboard and burying the wreckage in snow and ice.
A mystery regarding Star Dust that remains unsolved to this day relates to the flight's final Morse Code transmission to the Santiago airport, received four minutes prior to its planned landing. The last word of the transmission – heard by the airport control tower's radio operator as "STENDEC" – has never been satisfactorily explained, despite speculation from numerous aviation and radio experts and members of the public.