Visitors look at a Lockheed Martin F-35 fighter jet at the Singapore Airshow in 2010. The cost of the plane keeps on rising and is now $130 million or more per plane, depending on the model.

ROBERT SIEGEL, HOST:

The U.S. military is wrestling with the costs of what may be its most expensive program in history, the F-35 Joint Strike Fighter. The new fighter plane for the Air Force, Navy and Marines could end up costing more than a trillion dollars over its lifetime. The Pentagon says the plane is absolutely essential to replace its aging fleet.

On MORNING EDITION today, you may have heard NPR's Larry Abramson examine why the military wants the F-35. Now, he looks at the cost of the program and why some people feel it must be stopped.

(SOUNDBITE OF MACHINERY)

LARRY ABRAMSON, BYLINE: In a mile-long building on the edge of Fort Worth, Texas, an assembly line is taking shape to build the F-35. Lockheed Martin, which got the contract to build the jet back in 2001, is slowly cranking up production. It's hard to keep a plane current when it takes so many years to develop. But Lockheed's Kevin McCormack says the F-35 is designed to change as technology evolves.

KEVIN MCCORMACK: It's essentially a flying computer and so we want to take advantage of what's going to be out there in the future and put it on board this airplane in an effective, cost-effective manner.

ABRAMSON: Many planes already rely heavily on computer code, but the F-35 is supposed to up the ante. With nine million lines of code, it's also open to faster chips and better software as they become available. But many budget hawks and defense geeks say, the problem is that this plane just keeps getting more expensive. Right now, the cost of the Air Force version is nearly $130 million a copy. The Marine version, which flies like a jet but can land like a helicopter, is over $160 million. Lockheed says don't look at today's price. The cost will come down when this assembly line ramps up to full production later in this decade.

Lockheed's Mike Rein says, as long as the militaries of the world keep buying planes, the average price will come down to an affordable $65 million per copy.

MIKE REIN: You have to also look at the costs to maintain the platforms that this aircraft is replacing. Many of the countries are already seeing that their fourth-generation airplanes, some of them 40 to 50 years old, are extremely expensive to maintain.

ABRAMSON: But to keep the price of this new plane low, Lockheed has to sell a lot of them, around 3,000. The military will get a volume discount. But right now, it's paying a high price. It's complicated, isn't it? Many say this program has set a new standard for pricing complexity, even for the Pentagon. Winslow Wheeler, a defense expert with the Project on Government Oversight, says Lockheed uses a pricing vocabulary that masks rising costs.

WINSLOW WHEELER: Flyaway costs, non-recurring and recurring costs and lots of gobblygook and they'll say that comes to a number like 60, $70 million, and it's complete baloney.

ABRAMSON: Wheeler says if you figure in all the research and fixes to the design, the price rises out of sight. No matter what the actual cost, the issue has turned into a public relations battle for the military. The Pentagon defends the F-35 in public, while chastising Lockheed Martin over costs and delays. The general who's taking over the lead of the program at the Pentagon recently said that the military's relationship with the company is, quote, "the worst I've ever seen."

F-35 critics say the basic concept was faulty from the start. This one plane is supposed to do the jobs of as many as 10 older airframes. Winslow Wheeler says the F-35 is stretched between too many tasks.

WHEELER: They also made it a short takeoff and vertical landing airplane that they call STOVL. That has lots of design requirements that contradict what you need for either a fighter or a bomber.

ABRAMSON: Wheeler says the result is a plane that is mediocre at everything. Questions about the F-35's cost and performance have created a new international sport: trashing the plane online. It's a particularly popular game in the eight partner nations scheduled to buy hundreds of F-35s in the coming years. Peter Goon of the think tank Air Power Australia says data on the Joint Strike Fighter, or JSF, as it's known, showed that it's unable to achieve its main goal - competing with similar advanced fighters from China and Russia.

PETER GOON: Other countries are doing what they should be doing, that is producing capabilities to defend their sovereign nations. But unfortunately, the capabilities they're presenting now are far superior to the JSF.

ABRAMSON: Australia said it would delay some of its F-35 purchases in order to save money. And in December, the Canadian government threw its buy into question. The Pentagon says budget numbers can't describe the huge return they expect from this plane. Air Force Lieutenant General Frank Gorenc says, sure, it's expensive...

LIEUTENANT GENERAL FRANK GORENC: But it's also a procurement package that will put iron on the ramp for the next 50 years.

ABRAMSON: The growing cost of the program may be tempting for a Congress looking for budget reductions. But the military's bizarre procurement system could also protect the F-35. If the military orders fewer planes, it will pay more for each copy. So the F-35 could be too expensive to buy and too expensive to cut. Larry Abramson, NPR News. Transcript provided by NPR, Copyright NPR.