When approaching a vehicle that is turning towards your direction of travel it may block your lane for many seconds if it is a slow moving vehicle such as a tractor-trailer pulling from a stop.
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In this case a tractor-trailer pulled out from a driveway and was impacted by a car headed the opposite direction. The road was straight, well lit and relatively flat. Both driver's had a good view of each other and the collision could have been easily avoided by the tractor-trailer waiting to pull out when there was more space, or the driver of the car letting off the and/or swerving to avoid the truck. Given the speed of the car, letting off the gas 3.6 seconds before impact would have been enough to avoid the collision.
Judging Speed and Distance Speed Class Defensive