Pentagon stumped by mystery drone swarm flying over Langley Air Force Base

Not that there's anything important there – just F-22s and stuff

The former commander of the the Langley Air Force Base in Hampton, Virginia, has revealed an unidentified drone swarm buzzed the facility for 17 days last December.

According to retired US Air Force General Mark Kelly, the flyovers took place using a mixture of 20-foot long fixed-wing drones traveling at around 100mph (160 km/h) and smaller quadcopters. They appeared shortly after nightfall on December 6 and returned every evening in what he called "Close Encounters at Langley," Kelly explained to the Wall Street Journal.

According to the Journal's report, the drones would circle the airbase and also flew over the Chesapeake Bay and the US Navy's headquarters at Naval Station Norfolk. The drones were found to be using a different frequency band to commercially available kit.

The matter was considered sufficiently serious that it reached the White House, where deliberations considered how to stop the flights. Various ideas were proposed – including using directed energy weapons to disable or bring down the drones, although this was not carried out for fear of interfering with commercial airliners during the busy December travel season. Proposed attempts to jam the drones were also rejected for fear of disrupting 911 emergency coverage. A plan to bring them down with nets was also not implemented.

The airbase houses part of America's F-22 fighter fleet – among the most advanced aircraft in the US arsenal. After repeated drone visitations, night flying exercises were halted and the F-22s were moved to another airbase. On December 23 the drone flights stopped.

In an effort to unmask the drones' pilots, the US Coast Guard boarded a vessel just offshore from the airbase – but reported that there was no drone equipment on board. Local police also tried to follow the drones but couldn't find out where they were landing or who controlled them.

The drone flight reports come after similar aircraft were spotted over Edwards Air Force Base in California and the Energy Department's Nevada Nuclear Security Site outside Las Vegas. In no case have the operators been positively identified.

Authorities did claim one success in January, however, with the arrest and imprisonment of Chinese national Fengyun Shi, after he was observed flying a drone over a naval shipyard. Shi crashed his drone into a tree and abandoned it. Investigators recovered the machine and in its onboard storage found footage of naval craft under construction.

Shi was arrested after booking a one-way ticket to China, and was charged under US espionage laws. He described himself as a ship enthusiast who hadn't realized he was doing anything wrong.

"If he was a foreign agent, he would be the worst spy ever known," Shi's attorney Shaoming Cheng told the court.

Investigators found he had purchased his drone from big-box store Costco shortly before the incident. He pled guilty and was sentenced to six months in prison.

The mystery of the Langley flyovers remains unsolved for now. But it's clear the US will need to beef up its drone-deterrence tech fairly rapidly. ®