Welcome, defense-investing Fools, to the fourth installment of this series, in which we do our Foolish best to keep tabs on developments in the burgeoning field of pilotless, flying robots -- unmanned aerial vehicles, or "UAVs," to the initiated.

Today, we welcome Raytheon (NYSE:RTN) -- please stand up and take a bow! And everyone? Let's give Raytheon a big round of applause for its new UAV. The "KillerBee" wins the prize for the cutest name yet seen on a piece of military hardware and extra credit for being perhaps the prettiest UAV model we've seen yet.

Whose line (of work) is it?
Actually, Raytheon can't claim all the credit for the KillerBee, though. Credit for the idea, the design, and even the name goes to this UAV's manufacturer, specialty vehicle maker Swift Engineering. Moreover, the first time we learned of the KillerBee's existence, it was through a collaboration between Swift and UAV juggernaut Northrop Grumman (NYSE:NOC).

Northrop, as you know, is fast-becoming the dominant player in UAVs, having already launched such successful franchises as the RQ-4 Global Hawk, the MQ-5B Hunter, and the MQ-8 Fire Scout -- all prior to its latest success, claiming the Navy's Unmanned Combat Air System Carrier Demonstration (UCAS-D) contract to conduct carrier operations with the X-47B UAV back in August. By teaming up with Swift on the KillerBee, Northrop appeared to shift its focus back to land-based UAVs, challenging Boeing's (NYSE:BA) popular ScanEagle.

Totally radical, man
At first glance, it looks like it could be a successful challenge. Like KillerBee, ScanEagle is a small, catapult-launched UAV. But KillerBee has some technological advantages over ScanEagle.

For one thing, there's the radical shape. KillerBee resembles nothing so much as a miniature version of Lockheed Martin's (NYSE:LMT) famed (and now defunct) F117 Stealth Fighter, which could make it more difficult for bad guys to spot. Pundits reviewing the new bird suggest that the KillerBee's "blended-wing" shape will also add lift to the aircraft, thereby increasing endurance, fuel efficiency, and payload. The multiple sizes of the KillerBee are said to range from 6.5 feet all the way up to 17.5 feet, with payloads ranging from seven to 120 pounds depending on the variant in question.

Additional, perhaps unique advantages of the KillerBee include the fact that its shape may permit multiple stacked UAVs, one on top of the other, for shipping to theater. Its better-than-ordinary structural integrity might even permit in-flight deployment from a larger airplane. (Picture this if you will: An invisible B-2 [yet another Northrop bird], flying over the battlefield, opening its bomb bay doors, and deploying a dozen mini-spy planes midair. How cool is that?)

Too cool to escape notice
I'll leave the arguments for who's better, "ScanEagle" or "KillerBee," Boeing or Northrop, to the professionals at Jane's to decide. What I do know is that Raytheon is now giving Northrop a run for its money, and the major contractors are showing more interest in small UAVs than previously. Heretofore, we mainly saw the big boys focusing on UAVs with wingspans of 10 feet and up -- Northrop's Hunter, Textron's (NYSE:TXT) Shadow, Boeing's ScanEagle, and of course, General Atomics' Predator.

But the success of Honeywell's (NYSE:HON) "Micro Air Vehicle" and the number of contracts going to AeroVironment (NASDAQ:AVAV) -- currently the star of the less-than-five-foot-wingspan space -- may finally be attracting the attention of the majors. We discussed Lockheed's Desert Hawk back in August, for example. Now we see Northrop moving downmarket and Raytheon apparently entering the pool from the shallow end as well.

Does size matter?
But here's the curious part. As I wrote back in January, Army spokesmen have been quoted saying: "deployment of the unmanned systems will not go down, particularly for larger systems." But if funding is most secure for large UAVs, why are the majors shifting their focus and competing farther down the size scale? To me, it doesn't seem to make sense that they'd be pouring R&D dollars into the least favorable segment of the UAV market … unless conditions have changed since January. 

Unless smaller has perhaps become better. Personally, I'm surprised by the sudden shift of interest.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.