AS PASSENGERS fly in and out of Las Vegas’ main commercial airport, few are aware they are sharing the space with a secret airline that holds the U.S. government’s biggest secrets.

And it’s hidden in plain view.

Known only as Janet airlines, the flights transport employees and contractors from Las Vegas to the Nevada National Security Site’s top secret government bases, like the elusive Area 51, which conspiracy theorists believe houses crashed extraterrestrial aircrafts.

Due to the top secret nature of the airline, little is known about its operations. But a few interesting details have been uncovered over the years.

The airline, which runs numerous daily flights out of a private terminal at Las Vegas’ McCarran International airport, is owned by the U.S. Air Force and operated by a defence contractor named AECOM.

It carries approximately 190 passengers per flight, and is capable of transporting 1200 people everyday.

“They [Janet flights] are cleared of the whole runway, all the airplanes are supposed to park on the side and let the plane go first,” one pilot noted in 2008.

“You can’t see no names, no markings, no numbers, no nothing, nobody knows who’s in there. It could be the President. It could be anything.”

The first known Janet flight from Las Vegas to Area 51 was recorded in 1972 and flights use a three digit flight number including the prefix, WWW.

While no one has ever confirmed what Janet stands for, its commonly referred to “Just Another Non-Existent Terminal” or “Joint Air Network for Employee Transportation”.

The fleet consists of six unmarked Boeing 737-600s, highlighted by a red horizontal stripe on its sides. The planes are former Air China jets, with the exemption of two former models which were acquired in 2008 from the now defunct China Southwest Airlines. Five smaller jets accompany the fleet.

The aircraft are initially taken to Wright-Patterson Air Force Base in Dayton, Ohio, before their transfer to Las Vegas.

According to dreamlandresort.com, which hails itself as the leading Area 51 research web site, “heavily armed security are guarding the gates at all times. Hundreds of workers get on these flights each day and the parking lot is always packed with cars.

In a report by the Business Insider, a job ad for a flight attedant with the airline requires, “Active Top Secret or Secret security clearance”.

Purchased in 1955, Area 51 has been the testing ground for a host of top-secret aircraft, including the SR-71 Blackbird, F-117A stealth fighter and B-2 stealth bomber. Some believe the base is also a storage site for alien vehicles, evidence from the “Roswell incident” and extraterrestrial corpses.

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