With two months to go before it is scheduled to select the company that will

produce instrumented avionics rings for the Ares 1 crew launch vehicle, NASA quietly and unexpectedly narrowed the field of contenders to two finalists.

A total of five teams submitted proposals this summer for the nine-year Instrument Unit Avionics (IUA) contract expected to be worth an initial $300 million. Without making a public announcement, NASA informed Boulder, Colo.-based Ball Aerospace and Technologies and Houston-based Boeing Space Exploration

Oct. 4 that their Ares avionics proposals were the only ones that warranted further consideration ahead of a final downselect targeted for mid-December. The three bidder teams that did not make the cut were led by

BAE Systems, Honeywell Technology Solutions, and Raytheon Missile Systems.

NASA spokeswoman Beth Dickey acknowledged Oct. 9 that the U.S. space agency had narrowed the field of competitors the previous week. “And because the information is considered sensitive under government procurement procedures,” she said. “I cannot say which companies submitted proposals nor which companies will continue in the competition.”

While NASA cannot discuss the down

, the affected companies are under no such restrictions.

Ball Aerospace issued a press release Oct. 8 announcing it had made the cut. Boeing Space Exploration did not put out a release, but confirmed without hesitation that it, too, was a finalist. BAE Systems, Honeywell, and Raytheon all acknowledged they were out of the running for the prime contract and said they hoped to find work supporting the company that ultimately wins.

“We are disappointed in this decision but will apply what we learned from this experience to future NASA opportunities,” Raytheon spokesman John Patterson told Space News. “We feel we have some strong capabilities and technologies that would be of benefit to NASA programs.”

Honeywell spokesman James O’Leary acknowledged not making the cut, but said the company would “continue to explore ways to support NASA’s Ares I instrument unit avionics program.” He also noted that Honeywell is doing the avionics for the Orion Crew Exploration Vehicle as a subcontractor to Orion prime Lockheed Martin Space Systems of Denver.

Boeing spokesman Ed Memi told Space News the company was informed Oct. 4 by NASA that its proposal was considered “in the competitive range” and that Boeing should prepare to move ahead with more detailed discussions and negotiations.

“We consider ourselves a premiere avionics provider and have lots of experience doing this kind of work,” Memi said Oct. 8. “We look forward to sitting down with NASA and providing our best of Boeing approach to Ares 1 IUA.”

Boeing, in August, beat out the combined team of AlliantTechsystems, Lockheed Martin and Pratt & Whitney Rocketdyne to win a contract worth up to $1.13 billion to produce the Ares 1 upper stage at NASA’s Michoud Assembly Facility in New Orleans.

The avionics ring Boeing and Ball are vying to build will be mounted to the Ares 1’s upper stage to provide guidance, navigation and control for the entire rocket as it boosts the Orion Crew Exploration Vehicle into orbit. NASA has promised Congress to have the system ready to carry six astronauts to the international space station by March 2015.

Aerospace analysts who follow NASA said BAE Systems, Honeywell, and Raytheon – all major avionics vendors – appeared to have the advantage heading into the competition. But the indications out of NASA, these analysts said, are that the three avionics specialists were underbid by Ball and Boeing, two firms with greater experience winning NASA prime contracts.

One analyst, who asked not to be identified, said Boeing’s bid was so low that NASA felt the company had essentially “thrown it in for free” in anticipation of winning the Ares upper stage contract, which was not awarded until a few weeks after the avionics proposals were due. Ball, meanwhile, “did a good job building customer relations,” the analyst said, and reassured managers at NASA’s Marshall Space Flight Center that the Huntsville, Ala.-based field center would be calling the shots on the design effort.

Bill Townsend, Ball Aerospace vice president for exploration systems, echoed that point in an Oct. 9 interview.

“Marshall wants to lead the design effort and we’ve worked collaboratively with NASA on other programs on the design effort, so we know how to do that,” said Townsend, a former deputy director of NASA’s Greenbelt, Md.-based Goddard Space Flight Center.

Townsend noted that NASA took a similar approach during the Apollo program,

saying that the plaque at the base of a Saturn 5 avionics ring on display in Huntsville credits Marshall for designing the hardware and IBM for building it.

The avionics ring would be Ball’s first significant piece of Constellation, NASA’s program to replace the space shuttle and send astronauts to the Moon. Ball’s Constellation work to date has been limited to a couple of study contracts.

Townsend said Ball is sending reinforcements down to Huntsville daily to help the 30 or so people already there prepare for the final leg of the competition.