The US Air Force may have a stealthy spy drone replacement for the supersonic SR-71 that's secretly been flying for 9 years

• A new report from Aviation Week reports that the US Air Force's secretive stealth drone - commonly referred to as the RQ-180 - had its first test flight in 2010. The Northrop Grumman-designed unmanned aerial vehicle (UAV) has been in the skies for nine years without apparently ever being photographed.
• Developments at Beale Air Force Base and Edwards Air Force Base in California suggest that the UAV is currently engaged in operations, Aviation Week reports. It likely began flying at the Groom Lake testing facility at Area 51.
• Little is known about the design of the aircraft, but it is thought to be modeled after Northrop Grumman's X-47B drone, with a trailing edge like the B-21 Raider's.
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An in-depth report by Guy Norris in Aviation Week presents new evidence that a secretive, stealthy reconnaissance drone is now in operation with the US Air Force - and has been flying since 2010.

The unmanned aerial vehicle (UAV), thought to be called the RQ-180, is a large stealth craft used for reconnaissance missions, filling the role left open by the retirement of the SR-71 in 1999. There are no publicly available images of the UAV and an Air Force spokesperson said they were not aware of the drone. It is thought to be modeled after Northrop-Grumman's X-47B, Foreign Policy reported in 2013, and to have a relatively large wingspan and a trailing edge, similar to the B-21 Raider.

The RQ-180 likely began flying at the Groom Lake testing facility at Area 51, where the government's secretive U-2 testing was carried out in the 1950s. Aviation Week points to Aug. 3, 2010, as the first flight date for the aircraft.

In 2014, testing appears to have been moved to Edwards Air Force Base in California, with a long-range test flight - possibly to the North Pole - reportedly taking place in early 2017. Insider reached out to Edwards Air Force Base regarding the test flight, but did not receive a response by press time.

At Beale Air Force Base, also in California, the 427th Reconnaissance Squadron was recently re-commissioned and is now overseeing the operation of the drones, Aviation Week reports. A spokesperson from Beale AFB told Insider that they were not aware of the squadron. However, a press release from April on Beale AFB's web site celebrates the presence of the 427th Squadron at the ribbon cutting of Beale's new Common Mission Control Center, which will help provide ISR data in "highly contested areas."

According to Aviation Week, there are now at least seven of these UAVs currently in operation, performing a penetrating intelligence, surveillance and reconnaissance (ISR) role. "R" is the designation for a reconnaissance aircraft and "Q" means it is remotely piloted.

The US Air Force declined to comment to Aviation Week. Insider was told by the Air Force press officer on duty that the press desk was not aware of the program.