FAIRBANKS -- The U.S. Air Force selected Eielson Air Force Base as the preferred location for the first squadrons of F-35 fighter aircraft in the Pacific, the next step in a process that could lead to a final decision next year on basing 48 aircraft in Alaska.

"The decision means that in 2016, after completing an environmental impact statement process, one or two squadrons of F-35s will likely head to Eielson Air Force Base for stationing," a statement from Sen. Mark Begich said.

The Air Force did not select alternate sites in the Pacific for study, which was the biggest surprise with the announcement. Before their call with Air Force Secretary Deborah James, Begich and Sen. Lisa Murkowski said, they fully expected alternate sites to be included in the mix.

In a phone interview, Begich said the deployment could mean about 2,000 Air Force personnel and dependents would transfer to Eielson. He said the decision to include a preferred site and no alternates is a good one for Alaska.

"With the military aspects, there's no question where we rated," Begich said. "They just looked at the overwhelming evidence that Alaska is the right location."

In a phone interview with Murkowski, she said the selection of a single preferred location gives her confidence that the final decision will be to locate the aircraft in Alaska and not in Japan or Korea.

She said that the changes on the international scene make this a sensible part of the so-called "pivot to the Pacific" announced by the Defense Department in 2013. Alaska is close enough to potential global hot-spots and far enough away for security reasons, she said.

The "record of decision" is expected by fall 2015. The senators said about $170 million in military construction funds would be required in 2016-2017, with the first planes in 2019.

Both Begich and Murkowski said that the plan to move a group of F-16s from Eielson to Joint Base Elmendorf-Richardson, which was abandoned last October, reflected short-term thinking driven by immediate budget numbers and nothing else. They said the F-35 decision reflects long-term thinking and military strategy.

Murkowski said the Air Force secretary mentioned that a new review is to be made over the next few months of what will happen with the F-16 Aggressor Squadron at Eielson. Murkowski said James mentioned that keeping the 21 F-16s at Eielson is a possibility, but "there is a level of uncertainty on that front."

Moving the F-16s without the presence of a major Air Force mission was deemed to be the first step toward closure by many Fairbanks and Alaska leaders. The F-35 plan, while not final, changes the outlook.

The F-35, built by Lockheed Martin in Texas, is in what the Pentagon calls the "system development and demonstration phase," with the Air Force hoping for a declaration of "initial operating capability" by 2016. The Pentagon has taken delivery of more than 100 F-35s so far for flight tests.

The Pentagon budget for the next fiscal year includes more than $5 billion for 34 planes, while the House added $500 million to buy an additional four planes.

The Air Force decision means that an Environmental Impact Statement will be conducted to either confirm or reject the selection, according to the Alaska Congressional delegation, which received the news Thursday in a conference call with the Air Force secretary.

Lockheed Martin describes the fighter this way: "The F-35 Lightning II is a fifth-generation fighter, combining advanced stealth with fighter speed and agility, fully fused sensor information, network-enabled operations and advanced sustainment. As new threats to freedom emerge, it is more important than ever for U.S. and allied fighter fleets to have the F-35—the world's only fifth generation, international, multirole aircraft, capable of countering current and future threats."

The term "fifth generation" stems from a classification system under which subsonic fighters of 60 years ago made up the first generation. The F-22 Raptor was the first of the fifth-generation aircraft.

The Air Force has already decided that F-35s would be based at facilities in Arizona, Utah, Florida and Vermont, but it has yet to determine a site outside the Lower 48.

In February, the Air Force chose Eielson and Joint Base Elmendorf-Richardson in Anchorage for a site review, along with sites in Japan and Korea.

The Air Force has estimated that 48 planes would be housed at the location it selects in the Pacific region. So far about 100 of the new jets have been delivered to the military for flight tests, with full tests expected in four years. The Air Force calculates the cost per jet to be less than $100 million.

Each of the Air Force planes would cost $148 million, according to estimates published July 29 by F-35 critic Winslow Wheeler of the Project on Governmental Oversight, excluding costs for research, development, testing and evaluation. The versions for the Navy and Marines are more expensive, with an average cost per plane of $178 million.

Last fall, the Alaska Congressional delegation wrote to the Air Force: "We believe that Eielson is the perfect staging location for F-35 operations in the Asia-Pacific Theater and recommend giving it strong consideration."

A year ago, Gen. Herbert "Hawk" Carlisle, commander of Pacific Air Forces, said Eielson "fares very well, mostly because of the training space, the range."

"It's part of the Pacific and they can get to Northeast Asia rapidly," said Carlisle, a former Elmendorf commander.

The F-35 is the costliest weapons program in the history of the Department of Defense, with the contractor hoping to build more than 2,400 of them for the Air Force, Navy and Marines as well as other countries over the next quarter-century.

A Lockheed Martin executive defended the program in a letter to the New York Times Wednesday, countering an editorial by the newspaper questioning the wisdom of continuing with development.

Lorraine Martin, a Texas-based vice president and general manager of Lockheed Martin, said 65 percent of flight tests have been finished and that 107 aircraft have been delivered to the military, with more than 18,000 hours of flight time.

"Our responsibility is to provide the most advanced and affordable multirole fighter to our war fighters. We have no intention of relenting in this critical pursuit, especially when the imperative of maintaining future air dominance cannot be accomplished by buying more fourth-generation aircraft, as your editorial imprudently suggests," Martin said. "The war fighters who protect our freedoms deserve the best, and the F-35 will deliver decisive advantages over any potential adversary for decades to come."

A Times editorial July 28 cited numerous problems identified in studies and costs that have risen 42 percent since 2007 to $400 billion.