WASHINGTON — The U.S. Air Force is nearing a decision on the winner of a $13 billion contest to build its next fleet of search-and-rescue helicopters — a job that Sikorsky Aircraft hopes to secure.

The company based in Stratford, Conn., is offering a militarized version of its S-92 helicopter to replace the Air Force's current fleet of Sikorsky-built HH-60G Pave Hawks, but is facing stiff competition from familiar rivals. AgustaWestland is banking on its US-101 helicopter, which won the coveted Marine One contract a year ago, and Boeing is offering a modified version of its seasoned CH-47 Chinook helicopter.

A decision could come within the next two weeks. The Pentagon's Defense Acquisition Board has scheduled a meeting Tuesday where the Air Force will likely get a green light to name a winner. The Air Force has signaled the competitors to be ready for an announcement by mid-November.

"The key difference is the HH-92 is the most current design and the most survivable," said retired Maj. Gen. Michael N. Farage, director of USAF Programs for Sikorsky. "Ours is the only 21st century design out there."

Farage, who was a helicopter rescue pilot in the Air Force, said he has no doubt Sikorsky is offering "the best and safest" aircraft in the competition.

"I know a lot of the kids out there flying and I want them to have the best," he said.

The Air Force wants to buy 141 helicopters over the next 15 years so it will have a dedicated rescue fleet that can fly farther into hostile territory to rescue downed or injured airmen. It also wants a bigger cabin to accommodate larger para-rescue teams and potentially handle more wounded.

The Air Force wants room for four stretchers in the new helicopter. The Pave Hawk can only accommodate a single stretcher. In the past, rescuers have had to dump equipment to make room for additional wounded. Requirements also specify the replacement aircraft be able to travel greater distances. The HH-60 can fly about 160 nautical miles, do a 30-minute rescue operation and return. The replacement will be able to double the range, Farage said.

"The HH-60 was never designed for deep penetration rescues," Farage said. "In Afghanistan and Iraq, we don't have the safe bases out there, so the Air Force needs to be able to fly 300 or 400 miles."

Since 2001, the Air Force has rescued 722 U.S. and coalition personnel in Iraq and Afghanistan.

Farage expects all three competitors can meet the requirements sought by the Air Force. Sikorsky's HH-92, however, has a leg up when it comes to maintenance. It was designed to maximize the life expectancy of its parts and minimize the time the aircraft is idled for routine upkeep. Typically, a helicopter requires 15 to 20 hours of maintenance for every hour flown; the S-92 requires only three hours.

"That means operational readiness of 97 to 98 percent," Farage said. "Agusta is getting 80 percent with their US-101."

During the 2005 competition for the presidential helicopter contract, Sikorsky's S-92 had not flown enough hours to prove its reliability. Since then, Farage said, the helicopter has been heavily used in the North Atlantic ferrying cargo and personnel to offshore oil rigs.

Although Sikorsky is optimistic, aerospace analysts say the odds are working against them to win this competition.

"I still think the US-101 is the one to beat," said Richard Aboulafia, an aerospace analyst with the Teal Group in Fairfax, Va.

Aboulafia said the US-101 offers two advantages over the HH-92. It is bigger and a militarized version is already being developed for the Marine One program.

"This is going to be a Cadillac solution for the Air Force," he said. "Beyond that, a lot of the upfront research and development is being taken care of by the Marine One program."

Although the Boeing Chinook is the beefiest competitor, it is considered an older Army machine — something that would work against it given the "endless turf wars" that take place between the military services, Aboulafia said.

Loren Thompson, an aerospace analyst at the Lexington Institute in Arlington, Va., is convinced the HH-92 will not win.

"I suspect the problem is similar to the Marine One competition. The S-92 is too small," said Thompson, who also consults for Lockheed Martin, which has partnered with AgustaWestland on the US-101.

Thompson acknowledged that the S-92 has proven to be a reliable aircraft, but that won't overcome the fact that it is a smaller helicopter than either the US-101 or CH-47. Thompson said Pentagon officials would probably prefer the Chinook rather than add another platform, but those sentiments do not seem to be shared by Air Force brass.

Aerospace analyst Ray Jaworowski says the competition is too close to call.

"At this point, no one really stands out from the pack. The selection of any one of them would not be a big surprise," said Jaworowski, an analyst at Newtown, Conn.-based Forecast International.

Each competitor has its strengths, he said. The Chinook is the biggest and is a proven design. The US-101 is larger than the S-92 but is an Italian-British design rather than purely American. The S-92 is the newest design and perhaps mechanically better, but it is the smallest and size is a concern, Jaworowski said.