According to wired.com, the HEL MD system has "successfully engaged" drones and 60mm mortars, aka blew them the hell out of the sky. Tests were conducted at Florida's Eglin Air Force Base under cloudy and foggy conditions, making the weapon attractive for use in stormy naval situations.
The HEL MD currently uses a 10-kilowatt laser to scorch out its targets, although a more powerful beam will be used in future iterations. A “tactically significant power level” of 50 or 60 kilowatts will then be in force. Either way, the premise is simple: the laser's concentrated beam of light, when sighted on a target, soon turns into ever-expanding heat, disabling its target (possibly via a cool explosion, as "Star Wars" led us to believe.)
Quite awesomely, when mounted on a truck for mobility, the system requires only a driver and an operator with a laptop and Xbox controller to send up the lasery lightning. A telescope along with an infrared-based wide-angle camera helps to identify targets. The weapon is expected to be in development for several more years, so bust out your video games and get practicing...those enemy UAVs are in for a zapping.