Moments before that fatal fall ...
By Bronwynne Jooste and Murray Williams
Geoffrey Robson's life was tragically cut short after Base-jumping off a cliff on Duiwelskloof, between Helshoogte Pass and Pniel outside Stellenbosch.
Robson, 30, died shortly after 9am on Monday.
Originally from Noordhoek, he was an extreme sportsman and academic.
In his party on Monday were professional stuntman Leander Lacey and Patrick O'Connor, who also worked in the film industry.
O'Connor, who shot the photographs, said on Tuesday of their trek up the Groot Drakenstein mountains on Monday: "We started our hike up the gorge at about 5.15am. Geo (Robson) was the only one with a headlamp torch, so we were stumbling along getting scratched.
"We reached the top just before 9am," O'Connor explained.
"Leander and I were going to jump off the north face, a drop of about 800 feet."
Their jump was to have been a traditional "Base jump" - an acronym standing for Building, Antennae, Span and Earth - while Robson had been wearing a wingsuit.
Wingsuit flying is the sport of flying with an airfoil which creates lift, enabling jumpers to fly down more horizontally, before opening their parachutes for a safe landing.
O'Connor provided a photograph showing Robson's intended flight path, and also the trajectory which killed him.
Lacey said it was the first time Robson had attempted the jump, but said he was a mathematician and had calculated each step of the jump.
O'Connor said Robson had last week successfully jumped down the gorge (on the left in the main photograph) they hiked up on Monday.
"He was flying a new route and was proximity flying, where you can get quite close to the cliff.
"Geo was convinced that he could clear the saddle (to the right of the peak in the main photograph)," O'Connor said.
"That was his mission."
Robson was to have then boarded an afternoon flight to Switzerland where he worked and studied. He had been studying wingsuit flight to unprecedented accuracy by using a highly sensitive instrument which measured 3D location by GPS and inertial measurement, flyer attitude and heading, altitude, and air pressure during many wingsuit Base jumps.
Lacey explained that Robson's doctorate focused on how the airfoil worked and different speed glides. Robson had been an avid skydiver for years, but had only started wingsuit flying a year ago.
Lacey confirmed Robson's intended flight path.
"He calculated the glide ratios and used GPS co-ordinates. He knew what height he would be after 10 seconds, 15 seconds. This time he calculated he would be about 50 to 100m above the ridge.
"He did everything right, but there is always an inherent risk in proximity flying."
Of the fatal flight, Lacey explained: "He had a perfect exit and then made a 90186 turn, then he disappeared around the corner and we heard a loud bang."
Lacey said it appeared Robson had collided with a ridge, adding that if "he were two metres higher", he would have survived. The cliff face was about 1 000m above sea level and Robson had been travelling at about 'km/h when he hit the ridge, said Lacey.
Lacey then immediately alerted rescue officials.
Police were not able to reach the mountainous terrain and the Red Cross Air Mercy Service's helicopter was called in to airlift Robson.
He was already dead when rescue services reached him.
On Monday night Robson's father, Bill, described his eldest son as a "brilliant mathematician" who was most comfortable in the outdoors.
"He came here for a Base-jumping holiday. There is an element of danger, but this is just so tragic," he said.
Lacey said of Robson's last few days alive while visiting the Cape: "He opened up some new jump sites here in Cape Town, ones most people wouldn't go to because there is a seven-hour hike to the site.
"There was no way he was going to spend his last day in Cape Town just relaxing at home. Wingsuiting was his life."