- David Axe, military journalist

It's the most expensive weapon ever built in human history. But after decades of internationally-funded research and development at an estimated cost of a trillion dollars, a leaked report from a mock combat test reveals that the F-35 is terrible at air-to-air combat.

David Axe (Twitter)

"[The report found that] the F-35 cannot turn or accelerate fast enough to maneuver into an advantageous position to shoot at an F-16," says David Axe, a military journalist and blogger. "Nor can it escape an F-16 that's attacking it."

"The F-16 is not a new airplane," he continues telling As It Happens guest host Susan Bonner. "This is a 40-year-old design. The actual F-16 that the F-35 test pilot was battling against in this mock combat was probably more than 20 years old. It rolled off the factory line in the 1980s and also is one of the more sluggish F-16 versions. This particular airplane happened to be lugging two extra under-wing fuel tanks, which made it even slower."

A page from the leaked F-35 test with the pilot’s own account from mock air battles in January.

Currently, Canada's purchase of F-35s is on hold, but not out of the question.

Axe says that if the United States and Canada rely on F-35s as their only planes, that they will be outmatched by other countries' jet technology for the first time since the Cold War.

He acknowledges that dogfights are rare in modern warfare but takes the Turkish air force as an example: "[It has] been very busy with its F-16s patrolling the border with Syria and frequently shooting down Syrian jets and helicopters, which can involve close combat...You have to have the tecnology to either defeat in combat or deter an enemy from challenging you in the air. The problem with the F-35 is that it breaks a 50 year chain of technological superiority in the Western world."

Plane 'cannot be improved'

"The F-35's physical design is locked down," says Axe. "Lockheed Martin, other industry and allied governments have been working on this airplane for 20 years and have poured hundreds of billions of dollars into it. To change the physical design of the airplane means basically you're starting over and that's not going to happen. The fuselage, the wings, the engine, the avionics, these things are all integrated.

"It supports tens of thousands of jobs right now. Lockheed Martin has a marketing budget and a lobbying budget that exceeds the entire military budgets of small countries. It's now a politically unkillable program. And many, many people, senior generals, senior policy makers, have their careers invested in it."

Former Minister of National Defence and Minister for the Atlantic Gateway Peter MacKay checks out the cockpit of the F-35 Joint Strike Fighter following an announcement in Ottawa, Friday July 16, 2010. (Adrian Wyld/Canadian Press)

Axe won't say exactly how he got his hands on the report, "I got it from someone, who got it from someone, who got it from someone. I don't want to know. Someone inside the F-35 program leaked this document because they want people to know their plane doesn't work as well as it was advertised."

According to Axe, there are plenty of other jets on the market, "Eurofighter buids the Typhoon, the French build the Rafale, the Swedes have a delightful little airplane called the Gripen...[these] are superior alternatives." Others, have pointed to Boeing's Super Hornet.

He concludes: "The F-35's a decent attack plane if that's what you want it to do, to penetrate enemy lines and drop bombs. It's not an air-to-air fighter.

"If you need your airplane to fight air-to-air, you cannot buy this airplane."

The features of the F-35A Lightning are set out in a Department of National Defence technical briefing in March 2011. (DND)

The defence and security analysis group Jane's published a statement from the Joint Program Office (JPO) for the Lockheed Martin F-35, defending the plane: "While the dogfighting scenario was successful in showing the ability of the F-35 to manoeuvre to the edge of its limits without exceeding them and handle in a positive and predictable manner, the interpretation of the scenario results could be misleading. The F-35's technology is designed to engage, shoot, and kill its enemy from long distances, not necessarily in visual 'dogfighting' situations."

Take a listen to our interview and read more here.