The crash that killed Dag Hammarskjold

Alan Cowell has an article in The New York Times about a historical mystery:

The plane had flown deep into the African night on a mission for peace. Finally, it drew near its destination in the copper mining region of what is now northern Zambia. The crew radioed for permission to descend. Then there was nothing.
On the night of 17 September 1961, the plane, a Transair Sweden DC-6B named Albertina, was carrying Dag Hammarskjold (photo, top), the then-secretary general of the United Nations, and fifteen other people. Hammarskjold was on his way to meet with Moise Tshombe, the leader of a bloody secession movement in Katanga, a province of the neighboring Democratic Republic of Congo with vast deposits of strategic minerals, including uranium and cobalt. But the four-engined plane crashed (photo, bottom) minutes after the last radio contact, in a stretch of bushland eight miles from the airport at Ndola, in what was then the British protectorate of Northern Rhodesia. The crash turned a hinge in the tortured narrative of modern Africa, poised between rule by outside powers and independence. But its cause has never been established.
The United Nations has now agreed to reopen the Pandora’s box of fragmentary evidence, speculation, obfuscation, and wild conspiracy theories surrounding the crash to order a review by an independent panel of three experts.
A statement from the United Nations in New York City said the panel, led by a Tanzanian jurist, Mohamed Chande Othman, would be given three months to assess the “probative value” of evidence that has surfaced in the decades since the last formal inquiry. The other two panelists are Kerryn Macaulay, an Australian aviation expert, and Henrik Larsen, a ballistics specialist from Denmark. The three panelists will be empowered to travel to the scene of the crash and to interview witnesses. Notably, they may also draw on documents that the United Nations has urged its members to disclose.
Susan Williams, a British academic who has written an authoritative account of what is known about the crash, said that “it is extremely important for member states to deliver up documents”, including unpublished material from the United States, Britain, South Africa, France, and Belgium.
Some of the panel’s most sensational testimony may come from two American intelligence officers who were working hundreds of miles apart at listening posts in the Mediterranean. Both claim to have heard evidence that the plane was shot down, and one of them maintains that Americans were somehow implicated.
Charles Southall, now eighty, was a naval aviator in 1961, working at a signals intelligence base in Cyprus. He has told researchers and writers on several occasions that he was invited to come to the listening post near Nicosia on 17 September because something “interesting” was about to happen.
When he was there, Southall said, he heard a recording of a voice speaking over the sound of an aircraft engine: “I see a transport plane coming low. All the lights are on. I’m going down to make a run on it. Yes, it’s the Transair DC-6. It’s the plane.” Then came the sound of cannon fire, he said, and the voice spoke again, this time with more animation: “I’ve hit it. There are flames. It’s going down. It’s crashing.”
His recollections were included in a United Nations report published in 2013 and in other recent studies. Southall confirmed the account in an email exchange.
It was not clear exactly whom Southall had heard. But, four hundred miles away at Iraklion, Greece, another American was listening to high-frequency radio transmissions from central Africa that night. Paul Henry Abram was a Russian-speaking Air Force expert on loan to the National Security Agency, whose job was to monitor radio traffic among ground forces serving with the United Nations. He recalled that on one frequency, he heard a voice saying: “We have the plane in sight. The plane is well lit. We can see it approaching.” Then he heard an accented voice on a different frequency saying; “The Americans shot down the UN plane.” Abram, now a lawyer and author, said in a telephone interview that he alluded to this version of events in a 2013 memoir, Trona, Bloody Trona, but has never shared his version of events with Mr. Southall. And as for official inquiries into Hammarskjold’s death, he said, “no one has ever contacted me.”
Williams, the British academic, wrote in her study of the crash that a “Belgian pilot called Beukels” claimed to have shot the plane down by accident as it was approaching Ndola, after trying to force the pilots to divert to another airstrip.
None of these accounts of the crash have been independently corroborated.
Hammarskjold was flying to Ndola from Léopoldville, now called Kinshasa, the capital of the Democratic Republic of the Congo, which had gained independence from Belgium the year before. He was trying to broker an end to fighting in Katanga between United Nations troops sent to stabilize the country and secessionist forces backed by foreign mercenaries.
The wreckage of his plane was not spotted until the next afternoon, by a Royal Rhodesian Air Force plane based at Ndola. The sole survivor of the crash, Sergeant Harold Julien, an American security guard, died five days later without giving a coherent account of what happened.
Questions have been raised about the delay in locating the wreckage. The Royal Rhodesian officer who commanded the search, Squadron Leader John Mussell, wrote a detailed account a day after the crash, and recently made it available to The New York Times. His chronology indicates that warplanes, including a Canberra bomber, began searching possible crash sites in the early morning without success. He then met at 2:23 pm with the American air attaché in the Congo, Colonel Benjamin Matlick, and other officials to plan a coordinated search. The wreckage was finally spotted at 3:10 pm, fifteen hours after the plane’s last radio message, and a second aircraft flew to the area “to help with positive identification,” Mussell’s chronology said.
In a note accompanying the document, Mussell, now eighty and retired in Wales, acknowledged that early searches were “directed to the wrong area”, but he rejected “any thought that we, in the Air Force, were not on our toes, and further, as conspiracy theories would hint, were in some way involved in the disaster”.
He said in a telephone interview that the new inquiry should consider the role of the pilots of Hammarskjold’s plane. “It doesn’t matter how fatigued you are or how experienced you are,” he said. “If you are in Africa and going into unfamiliar territory, it’s not difficult to make a serious mistake.”
An inquiry by Rhodesian civil aviation authorities found that the plane had descended too low, and that neither pilot error nor foul play could be ruled out. A Rhodesian public inquiry in 1962 also cited low altitude. A United Nations inquiry the same year reviewed a range of possible causes without pinpointing one factor. But a United Nations panel reviewing the case in 2013 found that there was “persuasive evidence that the aircraft was subjected to some form of attack or threat as it circled to land”.
So much time has passed that the new inquiry “is probably our last chance,” Jan Eliasson, deputy secretary general of the United Nations, said in a telephone interview. “The more clarity we have on this tragedy, the better,” he said.

Rico says he was only nine at the time, but he remembers this crash...