Spaceflight Now Home

Mission Reports

For 12 years, Spaceflight Now has been providing unrivaled coverage of U.S. space launches. Comprehensive reports and voluminous amounts of video are available in our archives.
Space Shuttle
Atlas | Delta | Pegasus
Minotaur | Taurus | Falcon


Space Books

Delta 4 set for international launch Wednesday night

Posted: August 6, 2013

A United Launch Alliance Delta 4 rocket and its military communications satellite payload, both bought by Australia, will thunder to orbit Wednesday night from Cape Canaveral in an international collaboration to strengthen partnerships between the U.S. and its allies.

Liftoff time is 8:29 p.m. EDT. Credit: Justin Ray/Spaceflight Now
The spacecraft is the sixth in a growing constellation of Wideband Global SATCOM satellites, but the bird was purchased through an agreement that enabled Australia to gain access to the worldwide coverage provided by the U.S.-operated system.

Liftoff is scheduled for 8:29 p.m. EDT (0029 GMT) from Complex 37B at the Florida spaceport. The evening's nighttime launch opportunity extends 49 minutes to 9:18 p.m. EDT (0118 GMT).

See our Mission Status Center for live updates throughout the countdown Wednesday and streaming video of the launch.

Mission managers held the launch readiness review Tuesday morning and granted approval to proceed into the count.

Weather forecasters predict an 80 percent chance of acceptable conditions for liftoff, which will be ULA's seventh of the year and second using the Delta 4 to launch a WGS satellite.

Signed in 2007 between the U.S. military and the Australian Defence Force, the agreement runs through 2029, giving Australia a slice of the communications bandwidth available from the entire high-capacity fleet of WGS satellites that will span the globe.

The Australians contributed $707 million to WGS, funding the rocket and satellite going up Wednesday, plus sustainment costs of the system.

"The cooperation we've had with Australia has been extremely successful," said Dave Madden, the MILSATCOM director at the Air Force's Space and Missile Systems Center.

"It really helps all parties. It brings down our overall operating costs to operate the constellation and provides the capabilities to the U.S. (and) it provides critical capability that Australia needed to support its infrastructure as well as its warfighters. Third, it created interoperability between our forces. When we are deployed together we are operating on the same system. It really was a win-win, I believe, for all parties."

An artist's concept of WGS antenna arrangement. Credit: Boeing
The Air Force has launched five WGS satellites since 2007, with four currently in operation and the fifth nearing geosynchronous orbit for testing and checkout following its liftoff May 24.

"WGS is providing satcom for warfighters worldwide, both in X- and Ka-band. All of the services are using WGS, to include our international partners," Madden said.

A five-nation deal signed last year is funding the upcoming WGS 9 satellite and brings Canada, Denmark, Luxembourg, the Netherlands and New Zealand into the system.

Boeing is building the WGS constellation, which is replacing the aging Defense Satellite Communications System spacecraft. Each WGS has 10 times the capacity of a DSCS satellite, allowing users to process and receive data quicker than ever before.

"Every day, WGS helps save and improve the lives of users worldwide by providing critical comm links with the DOD and allied forces. This launch will be another important step in advancing these capabilities," said Mark Spiwak, Boeing's WGS program director.

ULA has launched the previous five WGS satellites, the first two occurring aboard Atlas 5 rockets and the more recent ones using Delta 4.

Wednesday's rocket will be flying in the Delta 4 Medium+ (5,4) version, which has a five-meter-diameter upper stage and nose cone, plus four strap-on solid-fuel boosters. The vehicle stands 217 feet tall.

It will take nearly 41 minutes from liftoff until spacecraft deployment into a supersynchronous transfer orbit. Boeing controllers will spend about three months using the satellite's conventional chemical engines and xenon thrusters to maneuver the craft into its test slot.

Madden said WGS 6's operational point in space has not been determined.

"I'm not sure where we are going to end up putting it. But from Australia's standpoint it doesn't matter because they've bought into a percentage of the constellation," he said.

"Symbolically, it would have been nice to say this one goes right over Australia, they could look up and say that was the one we bought, but it really doesn't matter to them, what they care about is the bandwidth and worldwide coverage."