Many unanswered questions still remain surrounding the 1987 plane crash of South African Airways (SAA) flight SA295.
The SAA Helderberg aircraft crashed into the sea near Mauritius in 1987, killing all 159 passengers and crew after a fire on board.
Captain Dawid Jacobus Uys was en route from Taiwan to Johannesburg via Mauritius when communications was lost over the Indian Ocean.
Over the decades, there have been numerous attempts to get to the truth, including the Margo commission of inquiry into the air crash.
There has been speculation of a political cover-up and allegations that the aircraft was carrying illegal cargo, namely rocket fuel and weapons.
Forensic scientist Dr David Klatzow says that the official commission of inquiry chaired by Judge Cecil Margo was a blatant whitewash.
Klatzow was consulted during the inquiry to try to ascertain whether carbon monoxide had caused the death of the passengers.
He believes that the aircraft was illegally carrying ammonium perchlorate or a similar chemical compound.
Peter Otzen Jr, an attorney whose father died in the Helderberg crash days before his birth, is still determined to get answers.
Otzen wrote to President Jacob Zuma asking him to appoint a new commission of inquiry into the disaster.
He says he has conducted research and interviews revealing crucial information which sheds light on what happened during what he calls an apartheid government atrocity.
It became quite obvious that the Margo commission of inquiry was part of the massive cover-up.— Dr David Klatzow, Forensic scientist
There's only one explanation of why Judge Cecil Margo tried to ban the readings of certain parts of the cockpit voice recorder.— Dr David Klatzow, Forensic scientist
It's a black spot in the history of South Africa; the willful murder of [passengers] aboard that flight. We need to get to the truth.— Dr David Klatzow, Forensic scientist
A new inquiry would bring down SAA if it found the truth.— Dr David Klatzow, Forensic scientist
Every single piece of information that we've uncovered has pointed in the direction of illegal armament and suppressed information.— Dr David Klatzow, Forensic scientist
There's definitely a smoking gun and we need to find out what happened.— Peter Otzen Jr, legal professional and son of Helderberg crash victim
Noseweek editor Martin Welz says he spoke to sources that informed him of SAA's suspicious cargo clearing controls and describes investigations at the time.
Listen to Dr David Klatzow and Peter Otzen Jr. clear the smoke on the Helderberg crash:
This article first appeared on CapeTalk : Quest to resolve alleged Helderberg crash 'cover-up' continues, 30 years on