He took no avoiding action as there was no time but assessed the risk of collision as being high, said the report.
Some 95 incidents were covered in the report (including military near misses) and 56 were found to have involved no risk of collision.
He said the demo version could only self-park in an area equipped with sensors and restricted to other robotic cars to avoid the risk of collision.
Airprox said aircraft safety had been compromised in 26 of the cases and there had been a risk of collision in nine other cases in addition to the three commercial air transport ones.
"As in 1998, more than three-quarters of the civil air transport incidents reported in the first half of 1999 were assessed as involving no risk of collision, " said Gordon McRobbie, director of the UK Airprox Board.
Science editor Alan Boyle's blog: Radar observations made during this week's close encounter with the asteroid Apophis have ruled out the risk of a collision with Earth in 2036, NASA says.
MSN: How to confirm we've found another Earth - Technology & science - Space - Space.com | NBC News
Only when the World Trade Center staff member has radioed back can the railroad and its workers be sure that each train has cleared the tunnel, and that there is no risk of a collision.
It said that, although Nasa was taking steps to protect the shuttle from orbital debris such as spent rocket bodies, satellite fragments and paint chips - there was a real risk that a collision could cripple the shuttle or threaten the safety of the crew.
Football is the collision sport that carries the highest risk of injury to every bodily joint.
The risk of an eventual collision with Europa, though small, is not zero.
Meanwhile, with so many ships trawling the crowded waters of the Gulf, there is always the risk of an "accident" or "collision" with unintended consequences.
That survey was requested by America's Congress nearly a decade ago, and was stimulated in part by the dramatic images of Comet Shoemaker-Levy, whose collision with Jupiter in 1994 generated a great deal of public awareness of the risk of asteroid impacts. (A couple of Hollywood films exploring doomsday scenarios also swayed opinion.) In 2005 Congress ordered the survey that is about to start.
ECONOMIST: The American Association for the Advancement of Science
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