Lewis Hamilton suffered a brake failure on his first day behind the wheel of his Mercedes on Wednesday, but insisted he had survived more horrifying smashes.

The 28-year-old 2008 world champion was on his 15th lap when he careered off the Jerez track and into a tire barrier having just moments earlier reached speeds of between 260kph and 300kph.

"I hit the brakes and in a split-second they didn't work. The pedal went down and nothing happened, so I just braced for the impact," said Hamilton, after the accident which took place on the second day of pre-season testing.