I had that happen with a 1x4 that was not tied onto the guys ladder rack correctly. it hit the pavement bounced up and smashed my hood and roof on my cavalier. it freaked the living hell out of me to see this board flying at me. the construction company was pretty cool about it though. i took my car to my repair shop, and got a quote and went to the companies office and the owner cut me a check since i was moving out of state in two weeks.