Delta IV successfully places GPS IIF3 satellite in orbit
Article by: Mike Barrett Date: 5 Oct 2012
On Thursday 4th October the third of the new range of GPS IIF navigation satellites was launched into orbit. There was a perfect countdown with everything proceeding on schedule to the target T-0 of 8:10am EST. As the countdown clock wound down the weather conditions improved with an 80% chance of launch quoted at the weather briefing during the T-4 minute hold.
The seconds were ticking away when the launch controller polled the 30+ stations monitoring individual functions on the rocket, the launch pad, the flight range and the weather. Each of the stations reported GO across the board and the mission director gave the launch conductor permission to launch. At 8:06am the countdown restarted at T-4.
The terminal countdown continued to T-5 seconds when the main booster was ignited. The lower part of the Delta IV rocket was engulfed in a fireball of hydrogen burn off. As the last few seconds ticked away the main engine built up power until T-0.01 seconds when the twin solid rocket motors were lit. At 8:10 the hold down was released and the rocket blasted off on its 3 and a half hour trip into orbit.
Later in the day the successful deployment of the satellite was confirmed by ULA and the USAF. Now there will be a period of testing and checking out the operation of the satellite prior to inserting it into the operational GPS constellation.
There are three more GPS IIF satellites already built by Boeing waiting for launch vehicles and constellation requirements. Despite worries a couple of years ago with doom and gloom being spread about the stability of the GPS constellation it has proven that the current satellites are lasting far longer than their specified operational lifetime. Currently the only reason to increase the deployment rate of the GPS satellites is to improve the functionality of the service rather than patch a failing constellation.
Last week saw the successful launch of a United Launch Alliance Delta IV carrying the latest GPS IIF satellite into orbit. The www.Wired4Space.com video is an edited version of the ULA launch feed with an overview of the mission followed by the launch to SECO.