Top-secret Northrop Grumman surveillance drone could make Air Force debut in 2015 A secret, new surveillance drone has been developed by defense giant Northrop Grumman. The drone, which is designed to conduct surveillance and reconnaissance missions, could enter operational service in the U.S. Air Force by 2015, according to news reports. The classified drone, dubbed RQ-180, is being tested at Area 51, a clandestine military base in the Nevada desert that has famously been used to test different spy planes since the 1950s. Northrop, headquartered in Falls Church, Va., and the Air Force have been reticent to talk about the project, but the existence of the RQ-180 was first revealed in a report last week by Aviation Week. "The Air Force does not discuss this program," Air Force spokesperson Jennifer Cassidy told Aviation Week. The RQ-180 drone will likely be used for intelligence-gathering, surveillance and reconnaissance missions. The vehicle, which is equipped with radars, radio-frequency sensors and surveillance instruments, could also be used to carry out electronic warfare, an unnamed defense official told Aviation Week. 9 Totally Cool Uses for Drones The new drone is a larger, more advanced version of the Air Force's RQ-170 Sentinel, which was built by Lockheed Martin Corp. The RQ-170, which has been in service since 2007, was used to carry out several high-profile clandestine missions, including the 2011 raid on Osama bin Laden's compound in Abbottabad, Pakistan, that killed the al-Qaida leader. Aviation Week combed through Northrop Grumman's corporate financial statements and publicly available satellite images for clues about the new RQ-180 drone. Overhead photos showed new hangars were built at Northrop's plant in Palmdale, Calif., to accommodate aircraft with wingspans of more than 130 feet (40 meters), according to the trade magazine. For comparison, the RQ-170 Sentinel's wingspan is estimated to be between 65 feet and 90 feet (20 m and 27 m). But Lockheed appears to be embracing the robust competition in the field of drone technology. Last month, the Bethesda, Md.-based aerospace company announced that it plans to develop an unmanned, hypersonic spy plane capable of flying up to six times faster than the speed of sound. The so-called SR-72 will be able to travel at speeds of more than 3,500 mph (5,600 km/h), and will be able to fly to any location within an hour, company officials said. Follow Denise Chow on Twitter @denisechow. Follow LiveScience @livescience, Facebook & Google+.