Blindness and Hybrids...?

There was an news "blip" on CNN about an issue that blind people are having today, in the midst of all the new technology. The article discussed the face that the new hybrid cars are so quiet that people who can not see, and depend solely on their hearing to guide them, believe that the extreme quietness that comes with the new environmentally friendly cars could cause a grave problem. I just thought this was interesting to think about while reading the book for this week... I couldn't imagine what it would be like to be in Charlie's situation!