Whatever you may think of Lockheed Martin's (NYSE:LMT) short-term prospects now that no one's buying F-16s any more (or are they?), longer-term, prospects are looking good indeed.

Yesterday, for instance, lightning struck twice, in the form of a pair of news releases on the firm's new F-35 Lightning II. First up, domestically, the Pentagon authorized the purchase of six "conventional" F-35A aircraft for the Air Force, and tentatively approved the purchase of another half-dozen F-35B aircraft -- the short takeoff / vertical landing, or STOVL, variant -- for the Marine Corps. Total sticker price: $2.2 billion. Meanwhile, overseas, Israel was reportedly placing a request to be allotted somewhere between 25 and 75 F-35s. (Which variant was not made clear, but Israel's a pretty tiny country -- you gotta figure they're going for the B version.)

Clearly, the F-35 is gaining popularity both at home and abroad, which is good news not only for Lockheed, but for its partners in production, Northrop Grumman (NYSE:NOC), GE (NYSE:GE), and United Technologies (NYSE:UTX). In addition to the Pentagon and Israeli contracts, we're seeing the F-35 featuring prominently in a Euro-dogfight to provide 48 fighter jets to the Norwegian Air Force. And if you add up the numbers reported on Wikipedia, total orders for the plane are eventually expected to fly past a few thousand worldwide, with nations as far-flung as the U.K., Australia, and Canada all placing orders.

The conundrum
The thing that confuses me, from an investor's point of view, is just how much the plane costs. The numbers quoted are all over the map.

Starting at the bottom, Reuters reports that the planes Israel wants to buy should cost about $80 million -- roughly in line with the $83 million cited on Wikipedia. In contrast, the Norwegians appear to be getting totally taken to the cleaners. Some news reports suggest that Norway's four dozen planes could set them back $11.7 billion -- a whopping $244 million apiece.

Military math
My hunch, though, is that the "$11.7 billion" number is off. I suspect it refers not just to the initial order of 48 planes, but perhaps to the total estimated cost of all the F-35s that Norway might ultimately order if Lockheed wins. A separate Reuters story supports this view, quoting a Lockheed official who puts the price tag at a more reasonable $3.9 billion for the first sortie. That works out to just a little more than $80 million a pop.

Which seems cheap... until you multiply it by 5,500 planes. Then you're looking at $440 billion in eventual revenue for Lockheed. Shocking.

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