Narain Karthikeyan's high-speed spin during qualifying for the Korean Grand Prix was caused by his front-right brake disc splitting in half.
The HRT driver was unable to complete a lap in qualifying after spinning at the fastest part of the circuit. It is not yet known what the cause of the failure was, although it is possible that wear was a factor.
"When you first come out of the pits you don't break at first," Karthikeyan said.
"I got to the third corner, touched the brakes and it [the brake disc] broke into two. I don't know the cause and it was a huge spin."
Despite not posting a time, the Indian will be allowed to start the race having posted competitive laps during free practice. Karthikeyan was frustrated at not having the chance to mount a qualifying attempt as he had outpaced team-mate Pedro de la Rosa during free practice.
"Here, it was possible to [outqualify de la Rosa] because we have a better balance with the car," said Karthikeyan. "My prime tire run this morning was faster than his qualifying."