Remember that plane crash I was on a few weeks ago:

"It took an hour for rescuers to find two people suspended upside down in an aircraft after it had crashed last month in a heavily wooded area of Bucks County.

The rescue would have been much quicker if the plane went down in neighboring Montgomery County.

That's because its 911 system allows dispatchers to track callers within a few feet of the location of their emergency call on a cell phone. "


More...
http://www.phillyburbs.com/pb-dyn/news/113-07092007-1375043.html