What is the F-35 Lightning II?

It is a stealth fighter aircraft with one engine and one seat. In March 2010, U.S. Defence Secretary Robert Gates said "it will become the backbone of U.S. air combat for the next generation." The F-35 is scheduled to go into service in 2011.

Lockheed Martin is the prime contractor.

What will it do?

The F-35 is designed for tactical bombing, aerial warfare and close air support for ground forces.

It will have a 25-millimetre gun, air-to-ground and air-to-air missiles plus a variety of bombs including, for U.S. planes, the B-61 nuclear bomb.

The F-35 can fly at more than 2,000 km/h.

What are the models?

There are three variants:

• F-35A: conventional take off and landing
• F-35B: short take off, vertical landing
• F-35C: for aircraft carriers

Each variant is about 15.4 metres in length. The F-35A and F-35B have a 10.7-metre wingspan while the F-35C's measures 13.1 metres. (The larger wingspan means the F-35C can land at a lower speed, cover a wider range and carry a larger payload. Only the U.S. will deploy this model.)

What is the JSF?

Joint Strike Fighter is the program to develop and acquire fighter jets to replace a wide range of existing aircraft currently in use by the U.S. and some of it allies. The program began in 1996.

"The focus of the program is affordability," the JSF website says. By using a mutual design for the three variants, with 80 per cent of the parts in common, the hope is to keep costs down.

But expert Winslow Wheeler of the Center for Defense Information in the U.S. told PBS, "The history of multi-role fighters, even for single services, is terrible. They do nothing well. ... The F-35 never will be able to fulfil its mission, because it is too heavy to fight other aircraft in the air, but too fast, thin-skinned and lightly armed to support troops on the ground."

What countries are participants in the program?

For the first time, an F-35B makes a vertical landing on the deck of a ship, the Marine Corps' USS Wasp, on Oct. 3, 2011. (F-35 Joint Program Office)

The nine partners, in order of their financial contribution, are the U.S., Britain, Italy, the Netherlands, Canada, Turkey, Australia, Norway and Denmark. Israel and Singapore are also part of the program as "security co-operative participants." Despite the partnership, the U.S. will foot the bill for about 90 per cent of the development costs.

Canada's investment in the JSF program totals about $168 million. Defence Minister Peter Mackay says Canada has already "doubled our return" through program contracts to Canadian companies.

The nine major partners are expected to buy about 3,100 F-35s over the next 25 years.

What's Canada buying?

Canada plans to buy 65 F-35A fighter planes. Delivery is scheduled to start in 2016 and take seven years

What does it cost?

The JSF is widely reported to be the most expensive military program ever — and costs are rising. One of the problems, Gates said in March 2010, is "overly rosy forecasts by the program office itself."

In June 2010 estimates of the cost of the American program rose again, to $382.5 billion US for 2,457 aircraft. That averages $156 million US per plane.

But cost estimates are likely to head higher. The estimates of the procurement cost per plane has already doubled since the program start and ongoing maintenance costs are also higher. With the program undergoing restructuring, the cost should rise even more, according to U.S. government's General Accounting Office.

"After more than 9 years in development and 4 in production, the JSF program has not fully demonstrated that the aircraft design is stable, manufacturing processes are mature, and the system is reliable," the GAO reported in May.

In Canada, the Department of National Defence reports a total cost of U.S. $17.6 billion for its 65 F-35s.

However, a report from Canada's Parliamentary Budget Officer in March estimated the total cost would be U.S. $29.3 billion.

There is a similar discrepancy in the two estimates for the cost per plane. DND pegs it at U.S. $75 million and the PBO says U.S. $148 million.

Bill Sweetman of Aviation Week, the author of two books on the F-35, says the rising costs of the fighter jet could be a "death spiral."

"The risk is that as the unit costs go up numbers come down, can the production process adapt?," Sweetman said in a telephone interview with CBC News.

Those lower numbers mean costs are likely to spiral higher and "right now there is no more money."

Why didn't Ottawa follow its contracting regulations before buying new fighter aircraft?

Defence Minister Peter MacKay climbs into the cockpit of an F-35 following an announcement in Ottawa, July 16. (Adrian Wyld/Canadian Press)It obtained a legal opinion confirming "suitability of invoking an exemption in Government Contracting Regulations because only one aircraft meets operational requirements," according to secret Canadian government documents obtained by The Globe and Mail.

"By signing the contract now we'll have an opportunity to bid on $12 billion in future contracts," something that would not be possible if Canada did not agree to buy the planes, MacKay told the CBC's Evan Solomon on July 16, 2010. MacKay insisted "there has been an open competition."

Sweetman says there was not a formal competition: "There is a lot of pressure from the United States to provide some good news for the Joint Strike Fighter program, which has been having a very tough half year of it."

Another one of those secret documents states a "competitive process would send signal to US/partners that we are not fully committed to JSF."

Sweetman is "very surprised" Canada is making this commitment now. "What they are doing is excluding any competitor at the point where they don't know what the aircraft will cost. They don't have a fixed price."

"These are the best planes for the coming threat challenge for the coming century," MacKay told Solomon.

What are the F-35's competitors?

Boeing is pushing the F-15 Silent Eagle and the Super Hornet, and the Eurofighter Typhoon and the Dassault Rafale are available in Europe.

How will the F-35 meet the challenge of communicating in the Arctic?

Military aircraft operating in the high Arctic rely almost exclusively on satellite communications but the necessary software will not be available until at least 2019, a senior Lockheed Martin official told Canadian Press.

A briefing to the chief of air staff in April 2010 discussed this concern and a study is looking at whether the sophisticated communications pod carried by Canada's CF-18s can be installed on the F-35.

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