STAR DUST

Opening

On 2 August 1947 Star Dust, an Avro Lancastrian of British South American Airways registered G-AGWH, left Buenos Aires for Santiago with five crew and six passengers. At 17:41 GMT the radio officer sent a routine message giving an arrival time of 17:45, ending with a word nobody recognised: STENDEC. The Chilean operator at Santiago queried it and heard it twice more. Nothing more was heard from the aircraft.

Searches found nothing, and for half a century Star Dust was a disappearance, with theories of sabotage, smuggling and flying saucers. From 1998 the glacier on Mount Tupungato began giving up an engine, wreckage and human remains. The aircraft had flown into the mountain in cloud. The crash is no longer a mystery. The word still is.

Timeline

29 July 1947Flight CS59 leaves London on an Avro York, Star Mist, reaching Buenos Aires on 1 August. Passengers transfer to the Lancastrian for the Andes crossing.

2 August, 13:46 GMTStar Dust departs Buenos Aires. Position reports follow at 15:07, 16:00 and 17:00, the last at 20,000 feet climbing to 24,000.

17:33 GMTThe aircraft gives an arrival time at Santiago of 17:45.

17:41 GMTThe last signal, ending STENDEC, is received loud and clear but very fast. On query the word is repeated twice in succession. All later calls go unanswered.

August 1947BSAA's chief executive, Air Vice Marshal Don Bennett, directs a five-day search. Chilean and Argentine teams find nothing.

22 December 1947Air Commodore Vernon Brown, Chief Inspector of Accidents, signs the British report. With no wreckage, it calls the cause obscure, raises severe icing, and finds the captain should not have taken the direct route in that weather.

1998Argentine climbers on Tupungato find part of a Rolls-Royce Merlin engine, twisted metal and clothing in the glacier at about 15,000 feet.

January 2000An expedition supported by the Argentine army recovers wreckage, a propeller, wheels and human remains spread over the glacier.

July 2000An Argentine air force officer, Major Luis Estrella, concludes that a heavy snowstorm and thick cloud caused the crash and clears Captain Cook of blame.

September 2002Relatives are told DNA samples match remains recovered from the site.

Key figures

Captain Reginald Cook, DSO, DFC, DFM, a decorated RAF wartime veteran, was 29. It was his first Andes crossing in command, after eight as second pilot.

First Officer Norman Hilton Cook, no relation, was on his first Andes crossing. Second Officer Donald Checklin had crossed four times.

Radio Officer Dennis Harmer, an RAF ground wireless operator in the war, sent the last message. He had made six Andes crossings.

Iris Evans, 26, from the Rhondda, a former Chief Petty Officer in the Wrens, was the "Star Girl", BSAA's term for its air hostess. It was her first Andes crossing.

The six passengers were Palestinian, Swiss, German and British, among them a King's Messenger carrying diplomatic papers and a German émigré, Marta Limpert.

Physical and documentary trail

The 1947 report survives in full, with the position reports, the weather forecast and the Santiago operator's account of the last signal. The forecast was bad: passes closed, cloud on the surface, snowstorms and moderate to intense turbulence in the Andes, with conditions "unfit for visual contact or instrument flying".

The wreckage settled the rest. It was concentrated, which pointed to a head-on impact and ruled out a mid-air explosion. A recovered propeller indicated the engines were near cruising power, and the undercarriage was still retracted, so this was not an emergency landing. The usual reconstruction is that the crew, flying in cloud into strong headwinds from what is now called the jet stream, overestimated their ground speed, believed they had crossed the peaks and began descending into Tupungato. The impact probably triggered an avalanche that buried the aircraft within seconds, which explains why searchers saw nothing. Some former BSAA pilots doubted Cook would descend without a positive fix and suggested the weather brought the aircraft down in another way.

The earlier version of this report was right on eleven aboard, the 17:41 time and the operator's description. It said the word came "once more" after the query. The official report says it was repeated twice. All times in that report are GMT, not local.

The Chilean Air Force operator at Santiago states that the reception of the signal was loud and clear but that it was given out very fast. Not understanding the word "STENDEC" he queried it and had the same word repeated by the aircraft twice in succession.

Things you might not know

• The report admits defeat in one line. It says simply: "A solution to the word 'STENDEC' has not been found."
• STENDEC is an anagram of DESCENT. BBC Horizon viewers sent in hundreds of proposed solutions after its 2000 programme, the anagram among them. The programme's staff found none of them convincing, except possibly a Morse misunderstanding.
• The dots and dashes match another message. Run together without letter spacing, STENDEC has the same Morse sequence as SCTI AR: SCTI is the code for Los Cerrillos airport in Santiago and AR is the Morse signal for end of message. That is a calculation for this report, and it needs the spacing to have been sent or heard wrongly.
• Remains surfaced after more than 50 years. Bodies freeze-dried in the glacier were found in a remarkable state of preservation, including a manicured hand thought to be Iris Evans's.
• BSAA lost two more aircraft without trace. Star Tiger vanished in January 1948 and Star Ariel in January 1949, both near Bermuda, feeding sabotage theories about Star Dust.

Competing explanations

For the loss of the aircraft, the matter is settled. Wreckage, remains and the flight's last reported positions fit controlled flight into terrain in cloud. Sabotage, a bomb, a hijacking or a UFO are ruled out by the concentrated wreckage on the mountain, on the line of the planned crossing.

For the word, several readings remain open. A Morse spacing error, by Harmer sending fast or by the Santiago operator, is the simplest, and the SCTI AR match shows how one could happen. Hypoxia scrambling a word such as DESCENT is possible, although the oxygen system was fully charged and checked before departure. An acronym or private code has never been identified. A misreading at Santiago has to survive two repetitions after a query.

Later life of the case

Star Dust was the subject of Horizon's "Vanished" in 2000, broadcast in the US by NOVA, and of Jay Rayner's book Star Dust Falling (2002). The glacier is expected to release more wreckage as it moves and melts.

Finding

Star Dust was not lost to mystery. It flew into Mount Tupungato in a snowstorm on 2 August 1947, killing all eleven aboard, and the glacier hid it until 1998. That part of the case is closed by recovered wreckage and identified remains. The final word is a different matter: it is documented exactly in the official report, and nobody has explained it.

What still will not resolve: what Dennis Harmer meant by STENDEC. He died with the aircraft, and no reading yet fits both the letters and the circumstances well enough to settle whether it was a slip of the key or a message.