Robbie Marshal defies death and flips his motorbike over a helicopter’s spinning blades. The 2012 Formula 1 Australian Grand Prix is almost here and \'Crusty Demon\' rider Robbie Marshall geared up for the event with an incredible stunt at the Avalon Airport in Melbourne, Australia.The 28-year old Marshall flipped his bike over a helicopter with the blades spinning near top speed.He and his teammates will compete against FMX riders from all over the world head-to-head for a £30,000 grand prize.