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en.m.wikipedia.org
On lap 22, the
Shadow-
Ford of Italian driver
Renzo Zorzi pulled off to the left side of the main straight, just after the brow of a hill and a bridge over the track. He was having problems with his
fuel metering unit, and fuel was pumping directly onto the engine, which then caught fire. Zorzi did not immediately get out of his car as he could not disconnect the oxygen pipe from his helmet.[nb 1]
The situation caused two marshals from the pit wall on the opposite side of the track to intervene. The first marshal to cross the track was a 25-year-old
panel beater named William (Bill). The second was 19-year-old Frederik "Frikkie" Jansen van Vuuren, who was carrying a 40-pound (18 kg)
fire extinguisher.[1]George Witt, the chief pit marshal for the race, said that the policy of the circuit was that in case of fire, two marshals must attend and a further two act as back-up in case the first pair's extinguishers were not effective enough. Witt also recalled that both marshals crossed the track without prior permission.[2] The former narrowly made it across the track, but the latter did not. As the two men started to run across the track, the cars driven by
Hans-Joachim Stuck and
Tom Pryce came over the brow of a rise in the track.[3]
"As we got to the top I suddenly sensed this marshal running across the track from my right, carrying an extinguisher. I took a big chance and I don't know how I got away with it. There was no time, I just reacted on pure instinct."
Hans-Joachim Stuck[4]
Pryce was directly behind Stuck's car along the main straight. Stuck saw Jansen van Vuuren and moved to the right to avoid both marshals, missing Bill by what journalist David Tremayne, calls "millimetres". From his position Pryce could not see Jansen van Vuuren and was unable to react as quickly as Stuck had done. He struck the teenage marshal at approximately 270 km/h (170 mph).[5] Jansen van Vuuren was thrown into the air and landed in front of Zorzi and Bill. He died on impact, and his body was badly mutilated by Pryce's car.[6] The fire extinguisher he had been carrying smashed into Pryce's head, before striking the Shadow's roll hoop. The force of the impact was such that the extinguisher was thrown up and over the adjacent grandstand. It landed in the car park to the rear of the stand, where it hit a parked car and jammed its door shut.[4]
The impact with the fire extinguisher wrenched Pryce's helmet upward sharply. Death was almost certainly instantaneous. Pryce's Shadow DN8, now with its driver dead at the wheel, continued at speed down the main straight towards the first corner, called
Crowthorne. The car left the track to the right, scraping the metal barriers, hitting an entrance for emergency vehicles, and veering back onto the track. It then hit
Jacques Laffite's
Ligier, sending both Pryce and Laffite head-on into the barriers. Jansen van Vuuren's injuries were so extensive that, initially, his body was identified only after the race director had summoned all of the race marshals the next day and he was not among them.[7]
next year you can have Merc fans entering the best of the losers competition. 
