As the number of GPS receiver devices increases significantly, so does our dependency on the GPS, but satellites are subject to wear out and age.
THE U.S. Air Force has since launched 2010 the second constellation of GPS satellites, named GPS Block IIF, or GPS IIF, built by Boeing. These satellites will replace the GPS IIA satellites of the first constellation, launched between 1990 and 1997, with lifespan design about 7,5 years.