As Congress begins deliberations on the Pentagon’s 2006 budget request, staffers are hinting that the U.S. Air Force’s proposed Space Radar demonstration, now targeted for 2008, likely will be delayed if not canceled outright.

Congressional skepticism about the utility and cost of an operational radar-surveillance constellation — and the proposed two-satellite demonstration as well — continues to run deep. That means Air Force Brig. Gen. John “Tom” Sheridan, director of the Pentagon’s newly revamped Space Radar program office, has his work cut out for him.

In a telephone interview April 25, Sheridan said his office is laying the groundwork for a demonstration that will prove that the Space Radar will both work as advertised and be affordable. He conceded, however, that the launch of the quarter-scale demonstration satellites may get pushed into 2009, regardless of the action Congress takes this summer.

The Air Force unveiled plans for the Space Radar demonstration late last year after Congress slashed its budget request to develop an operational constellation of surveillance satellites dubbed the Space Based Radar. Now simply called Space Radar, the system is intended to gather imagery for the intelligence community, detect movement on the ground for the military and make digital terrain maps for both camps.

Congressional staffers say the proposal for a demonstration in 2008 indicates that the Air Force did not get their message last year, which was to take a more cautious pace on the effort.

The Air Force has requested $226 million for the Space Radar in 2006. Staffers warned that Congress will use its budget authority to delay the demonstration or cancel it altogether, in part because the Air Force has yet to provide an estimate of how much the experiment or the operational constellation would cost. Previous estimates for a nine-satellite constellation have run as high as $34 billion.

Sheridan said the Air Force is still working on cost estimates for the demonstration. Preliminary cost estimates for an operational system will be available in about a year, he said, cautioning that the Air Force needs to conduct the demonstration before it can produce truly reliable projections.

The 2008 target date for the demonstration is driven by the expectation that the operational system will be needed by 2015 to replace the radar-imaging satellites that the intelligence community will be using at that time, Sheridan said. If Congress delays the demonstration, the Air Force might still be able to recover lost time and be ready to begin launching the operational satellites around 2015 , he said.

Scrapping the demonstration will make it difficult, though not impossible, to press ahead with confidence on the operational system, Sheridan said.

The initial focus of the Space Radar program office will be to work out a test plan for the radar sensor technology, Sheridan said. The plan likely will involve airborne tests of a prototype sensor, he said.

Leveraging existing designs for airborne radars also may be one of the keys to bring down the cost of an operational Space Radar constellation, Sheridan said.

The Space Radar program office has targeted the ground system as another possible cost-reduction avenue, Sheridan said. It may be possible to use a single ground-based tasking, processing and data-distribution for both the Space Radar and the reconnaissance satellites operated by the U.S. National Reconnaissance Office (NRO), he said.

Fostering collaboration between the intelligence community and military is a high priority for the Space Radar program office, Sheridan said. Among Congress’ concerns with the program is that the military and intelligence community have been at odds over the system’s capabilities and how it would operate.

In late January, Defense Secretary Donald Rumsfeld and CIA Director Porter Goss moved to address that situation by issuing a memo declaring that the Pentagon will field a single system to meet the needs of both communities.

Military and intelligence officials have since revised their Space Radar requirements , and began circulating new draft requirements documents among senior Defense Department leaders in April, Sheridan said. Those documents, the details of which are classified, are expected to be reviewed by senior Pentagon and NRO requirements officers in September, he said.

Sheridan said the Space Radar program office, which is located near NRO headquarters in Chantilly, Va., and whose No. 2 official, Robert Brodowski, is an NRO employee, also will foster cooperation between the two communities.