AIR & SPACE MAGAZINE Two Aircraft, Still No Pilot A second X-47B joins the flight test program. Northrop Grumman December 7, 2011 UCAS-D X-47B AV-2 is shown while undergoing proof load testing at Northrop Grumman's Palmdale Manufacturing Center. Northrop Grumman photo by Alan R Get the latest stories in your inbox every weekday.