Air Force GPS Satellite Launches Successfully
By Space Coast Daily // October 4, 2012
Will Use Delta IV Rocket
BREVARD COUNTY • CAPE CANAVERAL , FLORIDA – A United Launch Alliance Delta IV rocket carrying a Global Positioning Satellite was launched successfully this morning from Cape Canaveral Air Force Station.
Liftoff went smoothly at 8:10 a.m. and by the three-minute mark into the flight, the rocket was traveling at a speed of Mach 3.
The eventual orbit of the satellite will be about 11,000 miles above the earth.
The spacecraft is a Boeing GPS IIF-3 built for the U.S. Air Force.
GPS IIF-3s are the first satellites equipped with a fifth signal frequency, called L-5, which will be used for aerial navigation and search and rescue.
Earlier this week, Boeing repaired an issue with a cesium clock aboard the satellite and the company said its now ready for launch.
A problem was identified to be a xenon bulb with higher than expected pressure. The bulb is standard equipment aboard the satellite’s highly accurate cesium clocks, but inflating it to standard pressures could potentially shorten the satellite’s lifespan.
Boeing said the issue was resolved by drilling additional holes in the satellite and allowing more time in the vacuum to gas to escape.
In all, Boeing is contracted to build 12 GPS-IIF satellites for the Air Force and six have been completed and delivered. Two have been launched, one will be launched today and three are in storage awaiting launch dates.