His ambition was to become the fastest man on earth and Wednesday was the day he planned to break the record. Instead he crashed while travelling at close to 500km/h in a dragster powered by a jet engine.

South African landspeed record holder and former fighter pilot Johan Jacobs died tragically on Tuesday at Verneukpan, near Upington, when his jet car, Edge, went out of control and flipped during a practice run for Wednesday's attempt to break the 24-second world record for the standing mile over 1,64km.

After the tragedy, plans were cancelled to host a large group of motoring journalists in a desert tent camp. They had been invited to watch the attempt to break the record.

It is understood the crash took place during a practice run when the jet car, Edge, which was capable of reaching speeds of more than 500km/h, suddenly went out of control. Full medical back-up was on standby but were unable to save Jacobs.

At earlier runs the jet dragster had already proved its ability to complete a standing-start one kilometre run in a mere 9,4 seconds at a staggering terminal speed of around 509 km/h.

Jacobs, who was managing director of Gauteng's Jet Stream Drag Racing Promotions, held the South African top speed and standing-start one kilometre records, as well as the fastest quarter-mile (400m), achieved in the same jet dragster which was specially built for record runs at more than 500km/h.

A spokesperson for the organisers said that a statement would be issued later on Wednesday and that no further details were available.

Verneukpan is a large salt pan in the Kalahari, 150km south of Upington, and has been used to set numerous land speed records including an unsuccessful attempt by Sir Donald Campbell early last century.

Elaborate preparations had been made for Wednesday's cancelled event which included a professional camp site in the desert and the flying in of large number of support crew, press and motor industry dignitaries.

The Daily News motoring editor was to have flown to Verneukpan early on Wednesday to witness the attempt.

The specially-built Castrol Edge Showdown Jet Dragster slashed land speed and acceleration records and became a popular feature attraction at venues across the country, including challenging an L-39 Albatross (ZU-TEE) jet fighter, piloted by top aerobatic and commercial pilot Pierre Gouws, at the Jozi airshow in Mpumalanga last month.

"We need to continuously evolve the Castrol Edge Showdown concept and provide air show crowds with exciting new acts. Hence the introduction of the jet fighter to the Castrol Edge team," said Jacobs last month.

The result was a truly amazing spectacle and a phenomenal power-packed crowd-pleaser.

This display was the first of its type in South Africa, producing the ultimate showdown of speed and power as the Castrol Edge Jet Team raced down the Rand Airport runway. The airborne jet fighter had the advantage of flying past the starting point at around 200km/h before accelerating towards the quarter-mile and one kilometre markers.

As the plane passed overhead, Jacobs ignited the afterburner on the Jet Dragster, unleashing 11 000 pounds of thrust and thundering towards the finishing point at more than 500km/h.