Four days into the 2011 World Solar Challenge and things have proven even more challenging than usual for the participants. Teams have had to contend with huge road-hogging trucks, cars catching alight and bushfires that saw the race route closed by police, leaving the top three teams cooling their heels at an unscheduled stop at the end of day two while both the vehicles and the participants recharged their batteries.

After a relatively uneventful first day of racing, day two was a day of high drama with the three race leaders, Tokai, Nuon and the University of Michigan, forced to call it a day at Wauchope after police closed the Stuart Highway in both directions between Ti Tree and Wauchope due to bushfires - apparently the work of arsonists - burning across the road. The road closure resulted in the three leading teams - Tokai, Nuon and the University of Michigan - spending the night at Wauchope, while, the remainder of the field spent the night 100 km (62 miles) further north at Tennant Creek.

Day three saw drivers contending with dust devils - or in the local vernacular, willy-willys - and two huge trucks (or road trains) making their way north along the Stuart Highway. Despite these obstacles, the three leaders managed to extend their lead over the rest of the field with Team Tokai becoming the first team to cross the border from the Northern Territory into South Australia late on day three to spend the night at Marryat Creek, 1,825 km (1,134 miles) south of Darwin.

Meanwhile, the second and third placed Nuon and Michigan U teams spent the end of day three just back over the border in the Northern Territory at the Kulgera Control stop. But the competition is tighter about 200 km north where Ashiya from Japan, Aurora from Australia, and Twente from the Netherlands are jockeying for fourth, fifth and sixth place, and swapping positions throughout the day.

But the big news on day three concerned Team Philippines, which ended the day in 18th position but faced disaster after their car's battery overheated and set the car alight. Fortunately the fire happened after the team had already called it a day so there was no one in the car at the time and damage to the vehicle itself was minimal. As a result the team was forced to remain at Tennant Creek this morning attempting to make repairs. Their perseverance paid off with their car, Sikat II, finally rolling out of Tennant Creek at 11.14 a.m.

Due to the delays caused by the bushfires and forecast of overcast skies tomorrow, it will be touch and go as to whether any cars will make it to "Finish of Timing" point north of Adelaide by tomorrow (Thursday 19th of October) as originally expected. It's more likely the winner will cross the finish line around lunchtime on Friday, when the ceremonial finish in central Adelaide was originally scheduled to take place.

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