On 2 August 1947, the British South American Airways Lancastrian Star Dust disappeared crossing the Andes from Buenos Aires to Santiago. Eleven people were aboard. Its final Morse transmission ended with a word that made no sense: STENDEC. The receiving operator in Santiago asked for a repeat. It was sent twice more, identically, and then the aircraft was gone.
Fifty-one years of nothing
Searches at the time found no trace. The Andes are vast, high and heavily glaciated, and in 1947 there was no realistic way to search them. The aircraft was assumed lost somewhere in the mountains, and STENDEC became the kind of detail that generates decades of speculation — anagram theories, alien theories, coded distress theories.
The wreckage returns
In 1998, Argentine climbers on Mount Tupungato found aircraft wreckage and human remains emerging from a glacier. Recovery expeditions confirmed it as Star Dust. Rolls-Royce Merlin engines, a propeller, and personal effects were identified.
The location was the key. The wreckage was on a glacier well short of where the aircraft should have been, and the pattern indicated a high-speed impact into the mountainside — the debris subsequently entombed in ice and carried slowly downhill for half a century before emerging.
What actually happened
The explanation is meteorological. Star Dust was flying above the cloud in one of the first generations of aircraft able to cruise at those altitudes, and it very probably encountered the jet stream — a phenomenon barely understood in 1947 and not accounted for in navigation.
An extremely strong headwind would have meant the aircraft had covered far less ground than dead reckoning suggested. Believing it had cleared the Andes, the crew began its descent into Santiago. It was in fact still over the mountains, and it descended into Tupungato.
This also explains the timing of the STENDEC transmission: it was sent as a routine message announcing an imminent arrival, minutes before impact, by a crew who had no idea they were about to fly into a mountain.
And STENDEC
The most widely accepted explanation is prosaic: a fast, poorly received Morse transmission of STR DEC — an abbreviation for "descending" in the routine format used — misheard and transcribed as one word. The operator asked for repeats and received what he believed was the same thing, which is what happens when both parties repeat their assumption.
The mystery of Star Dust lasted 51 years and dissolved into two mundane facts: a wind nobody knew about, and a transmission nobody quite heard.