[Knox]

The Star Dust left Buenos Aires at 1:46 PM on 2 August 1947, bound for Santiago. Passengers were:
1--Casis Said Atalah, a Palestinian returning home to Chile from a visit to his dying mother;
2--Jack Gooderham, businessman;
3--Harald Pagh, businessman;
4--Peter Young, an agent for Dunlop;
5--Marta Limpert, with the ashes of her deceased husband, returning home to Chile after being stranded in Germany during the war;
and
6--Paul Simpson, a King's Messenger.

Santiago received a routine message in Morse Code from the plane at 5:41 PM, announcing an expected arrival in 4 minutes. The complete message was
"ETA SANTIAGO 17.45 HRS STENDEC". "STENDEC" was not recognized as a word. The Chilean Air Force radio operator at the Santiago airport described this transmission as coming in "loud and clear" but very fast. He requested clarification and heard "STENDEC" repeated twice in succession before contact with the aircraft was lost.

It was not until 1998 that mountaineers found some of the remains.

Quoted and paraphrased from an on-line article. I think it was this one.
http://www.pbs.org/wgbh/nova/vanished/stendec.html

The meaning of "STENDEC" (... - . -. -.. . -.-..) has not been discovered. Perhaps one or more spaces is in the wrong place. There are several Morse Code convertors on-line. One is at the above address. Here is another.
http://www.onlineconversion.com/morse_code.htm

New (2012) FAA Pilot/Controller Glossary
http://www.faa.gov/air_traffic/publications/atpubs/pcg/index.htm

Corps of Queen's Messengers
http://en.wikipedia.org/wiki/Queen%27s_Messenger

[Aaron]

Creepy. I'd say that's a typo but they repeated it multiple times...

[Diane]

STEN (~gun)
(Flight~) DEC[K]

[Knox]

Additional information, including (if I remember correctly) the mention that two other planes by the same airline disappeared.
BBC Horizon: Vanished, The Plane That Disappeared (1999)
http://www.youtube.com/watch?v=Zy8Ga6OmNx8