WASHINGTON — The requirements community within the U.S. Defense Department has recommended a future architecture for the U.S. Air Force’s Wideband Global Satcom (WGS) communications system that would keep eight satellites on orbit through 2025, but the Pentagon’s top acquisition official has not acted on the proposal, according to a Pentagon source.

The satellite communications requirements community, which includes the Office of the Secretary of Defense, U.S. Strategic Command and the National Security Space Office, submitted a final draft of a WGS acquisition decision memorandum with these recommendations to John Young, undersecretary of defense for acquisition, logistics and technology. Young has not signed the memo, and there have been no indications whether he will, the source said. Chris Isleib, a spokesman for the Office of the Secretary of Defense,could not comment on the status of the plans as of press time.

The WGS constellation, the first satellite which launched in October 2007, will serve as the backbone of the U.S. military satellite communications architecture over the next two decades. Boeing Space and Intelligence Systems of Seal Beach, Calif., is now under contract for six of the satellites.

Each of the geostationary-orbiting satellites is designed to operate for 14 years. If the recommended plan is approved, the Air Force may need to buy as many as 11 satellites to ensure an on-orbit constellation of eight satellites through 2025, based on the minimum design lives and current launch schedules of the WGS satellites. If the satellites exceed their minimum 14-year design lives, fewer could be required. Boeing announced in February 2008 it expects the first satellite to last 19 years as a result of better-than-expected fuel efficiency and a decision just prior to launch to top off the satellite’s tanks with additional fuel for its xenon-ion station-keeping thrusters.

If the Air Force buys a seventh and eighth satellite, they likely will be near-clones of the fourth, fifth and sixth satellites, the source said. The Pentagon is now considering whether and how it might evolve WGS capabilities for any satellites beyond the eighth, the source said.

Among the capabilities being studied for the next WGS block are satellite-to-satellite laser links and an Internet routing capability. Both capabilities originally were planned for the next-generation Transformational Satellite, or T-Sat, communications system, but the laser links were eliminated when the T-Sat program was scaled back in 2008. The Air Force now intends to award a prime contract for the $11 billion T-Sat system in April.

Meanwhile, the first WGS satellite positioned over the Pacific Ocean is exceeding data-rate expectations and its operational user community is very satisfied, Air Force Col. Donald Robbins, commander of the service’s Wideband Satcom Group said in a Dec. 22 interview.

“This was an interesting procurement for the government in that it’s 95 percent commercial parts and came off the Boeing commercial line,” Robbins said. “We knew they were using state-of-the-art commercial practices, but we were still surprised to see performance attributes exceed expectations.”

Upon entering service, the first WGS satellite more than doubled the military’s satellite communications capacity in the Pacific region, and the satellite is still not operating at full capacity, he said. While most of the compatible X-band terminals in the region are in place, the production and deployment of Ka-band terminals has lagged behind, as is often the case for new satellite systems, Robbins said.

The second and third WGS satellites originally were expected to be launched in 2008, but minor production changes and launcher issues have kept them on the ground, Robbins said. After the first satellite was launched, the Air Force and Boeing decided to change some manufacturing processes for the second satellite, which resulted in longer testing times for some components and a delay to its planned late-2008 launch. But the satellite’s deployment may have been delayed until 2009 anyway because of technical issues with its launcher, the United Launch Alliance-built Atlas 5 rocket. No Atlas 5 rockets have launched since April 2008.

The second WGS satellite is now scheduled for launch March 9 and will be positioned to support U.S. Central Command and the two wars being fought in Iraq and Afghanistan. It was shipped Jan. 20 from Boeing’s facilities in California to Cape Canaveral Air Force Station, Fla., in preparation for launch, a Jan. 21 Air Force press release said.

The third WGS satellite is slated to launch in July aboard a Delta 4 rocket to support U.S. African Command, Robbins said. The fourth satellite is in production and should launch in early 2011; the fifth and sixth satellites are entering full production and are slated to launch in 2012 and 2013, respectively.