Calgary-based CDL Systems may be the most important defense contractor you never heard of. But Lockheed Martin (NYSE:LMT) sure knows CDL. In fact, as of a few days ago, Lockheed owns CDL -- and with it, Lockheed bought itself a key piece of the infrastructure that controls unmanned aerial vehicles flown by everyone from Boeing (NYSE:BA) to Textron (NYSE:TXT), and from AeroVironment (NASDAQ:AVAV) to Northrop Grumman (NYSE:NOC).

Why was Lockheed's CDL purchase such a smart buy? Listen in, as Fool contributor Rich Smith explains.

Fool contributor Rich Smith owns shares of AeroVironment. The Motley Fool owns shares of Lockheed Martin, Northrop Grumman, and Textron. Motley Fool newsletter services recommend AeroVironment. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.