There's just one day left to go before AeroVironment (Nasdaq: AVAV) gets to report its fiscal Q1 2012 numbers -- but bless its heart, the little UAV-maker just can't seem to sit still and wait to tell us the good news. Unable to contain its enthusiasm, last week AV jumped up and gave a shout-out to DARPA for backing its new VTOL Shrike flying robot -- a robot that AV took from concept to prototype in just three weeks before getting down to the three-year ordeal of getting all the bugs worked out. Now the company has even more good news to report: It's just booked its first substantial order from the U.S. Army for a UAV with even greater potential.

Careful. That thing goes "boom."
That's right, folks: The Switchblade is finally in effect. Switchblade is a small unmanned aerial vehicle that's "launched" by firing it out of a bazooka. Once airborne, Switchblade can be flown like any other UAV off AV's common ground control unit -- flying around, looking for bad guys, streaming back live video of what it sees to its controllers. But it's what Switchblade does next that makes it unlike all other UAVs and makes it such a huge revenue opportunity for AV: Once Switchblade spots a bad guy, its controller can direct the UAV to ram the target and explode.

Now, many companies are working on weaponized UAVs -- Boeing (NYSE: BA), Lockheed (NYSE: LMT), and Textron (NYSE: TXT) are just a few of AV's bigger rivals with plans in the works. But as a general rule, their idea is to basically hang a rocket launcher on a big bird and teach the bird to shoot. AV's idea, in contrast, turns the "bird" itself into a bomb. Of course, any time a Switchblade actually does explode, it's time to buy another Switchblade -- a concept hearkening back to Raytheon's (NYSE: RTN) MALD decoy drone. Because the UAV is expendable, it's by definition going to need to be replaced -- creating a recurring revenue stream for AeroVironment.

Foolish takeaway
Investors responded positively to AV's Switchblade news last week, bidding the stock up 3% on after the $4.9 million contract was announced. Imagine how much more impressed they'll be when AV demonstrates that that first $4.9 million installment was only the beginning.

What will AeroVironment pull out of its bag of tricks next? Add it to your Watchlist and find out.