This may be what was flying around at the WTC on 9/11

Northrop Nabs Killer Drone Cash
By David Axe August 01, 2007 4:59:50 PMCategories: Drones
More than a year ago the Air Force unceremoniously dumped a promising program to build stealthy killer drones in partnership with the Navy. The sea service soldiered on with the so-called "Unmanned Combat Air System" program, aiming to launch killer drones from its aircraft carriers. Today the Pentagon announced that Northrop Grumman will build the prototypes at an initial cost of $640 million, with a due date of 2013. This is a big blow to Boeing, which had designed a lightweight drone, the X-45, that was more suitable to the Air Force. Northrop's X-47 is tougher and reflects the firm's experience building heavy F-14 fighters back in the '80s.
Next up in the robo-plane world: a contest to build 50 large maritime surveillance drones for the Navy. Northrop Grumman is offering its world-beating Global Hawk; General Atomics is pitching "Mariner" -- a naval Predator, basically; and Boeing has proposed an, ahem, unmanned Gulfstream business jet. Word was that Boeing had stripped its drone programs of people and money in a bid to keep the X-45 alive after the Air Force bailed. Now Boeing's drone shop is in shambles, with no X-45 and little hope of winning the maritime surveillance contract. The future is robots. And the robots are Northrop Grumman's.
Related:Boeing's drone shop on life support Navy doesn't want to talk about surveillance dronesMarines want small killer drones