"We can't always prove fatigue as a cause of an
accident, but the frequency with which we now routinely document
the presence of fatigue-related factors in transportation
operations is alarming."
Source: NTSB Chairman Deborah A.P. Hersman
speaking before the annual conference of the National Sleep
Foundation in Washington, DC.
Global Positioning System
A space-base radio positioning, navigation, and time-transfer
system. The system provides highly accurate position and velocity
information, and precise time, on a continuous global basis, to an
unlimited number of properly equipped users. The system is
unaffected by weather, and provides a worldwide common grid