On April 19th NASA and the FAA teamed up to conduct the largest test to date for the UAS Traffic Management(UTM) system under development by both organizations. There are six licensed test sites throughout the United States, located in Alaska, North Dakota, Nevada, New York, Virginia, Maryland and Texas. The Nevada test site is at the Reno-Stead Airport.
On April 19th the test team at Stead took part in the test by flying four drones simultaneously with drone flights at the other test sites. The UTM system monitored all flights from one location at NASA Ames Research Center in Mountain View, CA and, at the same time, inserted simulated aircraft traffic into the flight areas to evaluate their ability to monitor all of the traffic.
An article detailing the event and explaining the program in more detail may be found here.