On 19 October 1986, a Tupolev Tu-134 jetliner with a Soviet crew carrying President Samora Machel and 43 others from Mbala, Zambia to the Mozambican capital Maputo crashed at Mbuzini, South Africa.

While there was widespread suspicion in other nations that South Africa, which was hostile towards Machel's government at the time, was involved in the incident, no conclusive evidence was ever presented to support that allegation.

Upon reaching an altitude of 796 metres (2,611 ft) AGL the Ground Proximity Warning System (GPWS) sounded and remained on and, although the captain cursed, the descent continued.

[2]: 27–28 Pik Botha was alerted to the crash at 04:30 by a phone call from Minister Louis le Grange, who stated that Machel and 30-40 passengers on board had been killed.

[7] The first public indication of the tragedy was when Radio Mozambique switched to funeral music at 08:30 and Marcelino dos Santos, a member of the ruling FRELIMO Party announced President Machel's aircraft had not returned to Maputo as scheduled the previous evening.

[7] Mozambican security minister, Sérgio Vieira, traveled to Mbuzini with Pik Botha, and proceeded to the crash site and personally identified Machel's body.

[10] Violence erupted in Harare, Zimbabwe, when cars driven by whites were attacked by angry demonstrators, prompting an editorial rebuke in Mozambique that declared that Machel had been committed to a non-racial Africa.

Director Renee van Zyl of the South African Civil Aviation Bureau served a writ on Botha and the SAP, and received the two recorders at 15:45 on 11 November 1986.

[11] Eventually, agreement was reached for representatives of South Africa, Mozambique and the Soviet Union to jointly examine the CVR tapes under Swiss auspices in Zürich.

[2]: 14  Pik Botha would later state that on his recommendation, due to the mounting suspicions of South African culpability in the crash, the services of three foreign individuals were obtained, and these persons became three of the six members of the Board of Inquiry.

The board concluded that even just seconds before the impact had the crew performed the required procedures for a GPWS alert when flying over hilly or unknown terrain, quickly raising the nose and increasing power, this would have prevented the crash.

[19] Mozambique also provided a technical report prepared by Ron Chippindale of the New Zealand Office of Air Accidents Investigations examining the possibility of tampering with or replacing the genuine Maputo VOR signal with a decoy.

[20] The Mozambican analysis of and findings from the evidence led them to conclude:[21] The USSR, the state of manufacture of the aircraft, was given a draft of the final report and a chance to review and submit comments in accordance with ICAO convention.

[22] The Soviet delegation stated the theory that the crew had mistakenly selected the Matsapa VOR was contradicted by the known settings of the onboard navigation equipment and the timing of the turn.

[25] A LAM Airlines Boeing 737 flying at around the same time as the accident aircraft reported receiving the Maputo VOR signal unusually early, at a distance of about 350 kilometres (220 mi; 190 nmi).

[27] Receipt by the flight crew of the visual landing clearance from the Maputo controller implied permission to descend below 910 metres (3,000 ft) according to ICAO procedures.

[14] The pilots' speculative remark was revealed to Sérgio Vieira, Mozambique's minister of security, in a rash comment by South African police commissioner Johann Coetzee.

[1] The Margo commission's draft report then proposed Matsapa airfield's VOR, combined with pilot error, as playing a likely role in the trajectory followed by the aircraft.

[1] A breakdown in communications followed, causing Gen. Earp of the South African Air Force to authorise military pilots to penetrate Mozambique airspace to test the Matsapa theory.

[30] Mozambican authorities however remained unconvinced and suspended air controller de Jesus on 5 May 1998, for allegedly having been bribed to tamper with Maputo airport's beacon on the night of the crash.

[32] It concluded "The investigations conducted by the Commission raised a number of questions, including the possibility of a false beacon and the absence of a warning from the South African authorities.

In January 2003, the Sowetan Sunday World reported that an apartheid era killer and former CCB member, Hans Louw, serving a 28-year term at Baviaanspoort Prison near Pretoria, had confessed to participating in a plot to kill Machel.

[12][13][34][35][36][37] In a television documentary written and produced by South African TV journalist Johann Abrahams, Louw says: "So, when the plane reached that hill it was already lower than 1,000 feet [300 m].

According to the agreed Aircraft Accident Factual Report, signed by South Africa, Mozambique and the USSR on 16 January 1987, "Impact occurred at 19.21:39,[clarification needed] in darkness".

[2]: 22, 26 The Report of the official Board of inquiry adds that "...the aircraft struck the ground in the flight configuration, with landing gear and flaps retracted and the stabilizer in the cruise position".

Mandela cautiously claimed that the precise chain of events leading to Machel's death were uncertain and elusive, and repeated an earlier promise that no stone would be left unturned to establish the full truth.

Designed by Mozambican architect, Jose Forjaz, at a cost to the South African government of 1.5 million Rand (US$300,000), the monument comprises 35 whistling wind pipes to symbolise each of the lives lost in the air crash.

[47] At the Mandela-Machel wedding ceremony on 18 July 1998, Mandela was however reported to have announced that Samora Machel was murdered, without reference to the South African board of enquiry's findings.

Botha responded in a public interview on 16 May 1999 that although he had been one of the first people on the scene and was called on to identify Machel's body, the only facts he knew about the crash were the findings of the Margo Commission: "I totally reject any suggestion that I could have been a party to a decision of that nature.

An annual 7.7% decline in GDP under Machel's communist nationalisation policies, reverted to growth averaging 2.4% per annum under the freer, multi-party democracy in the tenure of his successor, Joaquim Chissano.