Since confirmation was requested and the word twice-repeated, there seems little doubt that stendec is accurate.
The meaning of the transmission has never been clearly determined, although theories abound.
Stardust was a Lancastrian airliner, a civilian design based on the famous Avro Lancaster bomber of World War II. On a flight to Santiago, Chile in 1947, the airliner vanished. Just prior to the infamous stendec transmission, the aircraft reported its expected arrival in Santiago in four minutes. A comprehensive search of a wide area, including what is now known to have been the crash site, revealed not the slightest trace of a crash.
The flight crew of the aircraft were highly experienced RAF vererans with many thousands of hours on type. The passengers included a King's Messenger carrying diplomatic documents that may have related to the UK's strained relations with the Peron government, a German emigre of suspected Nazi sympathies and a rich Palestinian, said to have been carrying a large diamond sewn into the lining of his jacket.
In 1998 traces of the aircraft were discovered on the surface of the Tupangato glacier in the Andes, giving the lie to UFO theorists.
Wreckage was well-localised, all located propellers showed engines that were running at near-cruise speed at time of impact and the undercarriage was retracted, suggesting controlled flight into terrain.
In 1947 the actions of the jet stream were not widly understood, and the Lancastrian was one of the few airliners capable of flying that high. Navigation would have been by dead reckoning. If the airliner had entered the jetstream, it is possible the crew thought they were descending through cloud towards Santiago, when in fact the were over the Tupangato glacier.
It is likely the airliner flew into a near-vertical snow field at the top of the glacier, thereby starting an avalanche that concealed the wreckage from searchers. The wreckage became incorporated into the body of the glacier, only for fragments to emerge years later, much further down the mountain.
No plausible explanation of the word stendec has yet emerged and it remains a mystery to this day.