Unmanned aerial vehicles. Lately, all the talk in aerospace circles has concerned the rise of the UAV in military importance. Honeywell's (NYSE:HON) got its T-Hawk (aka the "flying coffee can".) Textron (NYSE:TXT) knows the Shadow. And, Boeing (NYSE:BA)? Why, Boeing just set up a whole division devoted to building the contraptions.

Well -- pardon me for asking -- but does anybody make planes for pilots anymore?

"Um, we do"
Oh yes, Northrop Grumman (NYSE:NOC). Northrop just landed a $432 million contract to build two new E-2D "Advanced Hawkeye" command and control aircraft for the Navy. And according to the press release, this is just the beginning of what will eventually become a 75-plane complement of Hawkeyes. If you extrapolate from the contract price, this works out to $16.2 billion in future revenues for Northrop -- nearly six months' work for the company. Strangely though, news of the award did nothing to keep Northrop's stock price from following the rest of the market down yesterday.

Wonder why that might be?

I've got a notion
Call me a pessimist, but I'm not at all certain that this 75-plane fleet is realistic. Consider that if Defense Secretary Gates gets his way, we could be looking at a planned phase-down to a "10-Carrier Navy," but we're holding steady at 11 for the time being. Consider too that the ordinary aircraft complement on a Nimitz-class carrier includes four Hawkeyes. You can do the math: 11 times 4 equals ... well, a bit more than half the number of Hawkeyes we're told the Navy will ultimately order.

Granted, the Navy probably wants to have a few "spares" tucked away in case one of its new birds crashes or is down for maintenance. Still, the Navy's getting along just fine with 69 older model Hawkeyes in service today. If our carrier fleet is shrinking rather than expanding, I'd consider that a likely ceiling on the number of Advanced Hawkeyes the Pentagon will be buying in the future.

Foolish takeaway
Finally, consider that Joint Chiefs Chairman Admiral Mike Mullen, recently predicted that Lockheed Martin's (NYSE:LMT) F-35 would be "the last manned fighter" the U.S. ever builds. Considering that flying an airborne radar station is a whole lot simpler than jockeying a fighter jet, I can't imagine what would prevent this statement being applied to AWACS craft like the Hawkeye as well.

So, why weren't Northrop investors a bit more excited about the news? Seems to me that between a shrinking carrier force on one hand, and the advent of labor-saving UAVs on the other, Northrop's seeing a whole lot more Hawkeyes in the bush than it will ever get in hand.

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Fool contributor Rich Smith owns shares of Boeing. The Motley Fool has a disclosure policy.