Want to fly to Area 51? The world's most secretive airline is hiring

Adverts for professional vacancies have come a long way since they were hand-written paper cards stuck to the windows of Job Centres in the not-so-distant past. But even 30 years ago, you might have expected an appeal for an administration assistant in Crewe to reveal the identity of the company you were hoping to work for.

Things are a little more cloak-and-dagger in the case of an advertisement currently published in the recruitment section of the website for engineering company AECOM - titled "First Officer, Co-Pilot, Las Vegas, Nevada".

There is plenty of information on the nuts and bolts of what the role entails - applicants should be able to pilot an "aircraft to transport passengers and cargo," and "review maintenance logs, weather reports and forecasts".

They should also have "a thorough knowledge of the Airplane Flight Manuals, Flight Crew Operating Manual, and other documents and reports to ascertain factors such as aircraft weight and balance, fuel supply, route, schedule, and mechanical reliability."

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All standard stuff, you would say, in the casting of a net for a new pilot. However, one piece of information which is conspicuous by its absence is the name of the airline.

Why would this be?

Because this vacancy is - almost certainly - with an airline that is something of a secret.

"Something of a secret" is perhaps the best way to describe JANET, an airline whose existence is only loosely acknowledged - to the point that no-one is entirely sure what the acronym stands for. It may be a pithy, almost self-deprecating "Just Another Non-Existent Terminal". It has also been suggested that the five letters translate as "Joint Air Network for Employee Transportation". But, in truth, these are guesses.

What is known is that AECOM is the engineering firm responsible for the smooth running of this ill-defined presence in the skies. And that JANET is an airline operated for (or by) the United States Air Force (USAF) - with the majority of its flights either taking off from or landing at McCarran International Airport in Las Vegas.

What is also known is that it largely serves air-strips in the American west - Edwards Air Force Base in California and Hill Air Force Base in Utah among them (although it also flies to Wright-Patterson Air Force Base in Ohio).

Most intriguing, though, is that it touches down in the dust of southern Nevada - at both Tonopah Test Range and the notorious Area 51.

The USAF is tight-lipped about JANET's existence - even though it is probably no more than a commuter service, ferrying employees to their places of work. And its activities are visible. Even "secret" airlines have to file flight plans, and JANET flights can be seen on mainstream tracking websites (such as flightradar24.com). They are easily identified because the flight numbers have a recognisable prefix - WWW.

Furthermore, its planes can be glimpsed with the naked eye. They have a livery that is distinctive in being deliberately undistinctive - plain white with a narrow band of red running horizontally along the fuselage. Keen plane-spotters can watch them taking off from McCarran International. The aircraft - 11 in total, including six Boeing 737-600s - depart from the high-security Gold Coast Terminal, which sits on the west side of the airport complex (oddly, just behind the Mandalay Bay hotel). Zoom in on Google Maps and you can clearly see white-and-red JANET planes waiting at departure gates.

The mystery for potential applicants for the pilot vacancy is not what they will be doing as who they might be flying - and what these passengers do for a living.

In the past, Tonopah Test Range has been used for classified flight manoeuvres - it was the proving ground used in Constant Peg, a training procedure which saw American pilots fly against Russian MiG fighters between 1979 and 1988.

Area 51, meanwhile, is forever fixed in popular perception, even though the CIA only officially acknowledged its existence in 2013. Endless conspiracy theories claim it to be a site associated with extra-terrestrials and "alien" spacecraft (in folklore, it is where the "UFO" which "crashed" in Roswell, New Mexico, in 1947, was transported for examination). In reality, Area 51 is thought to be used for the testing of advanced - and, as yet, unknown - aircraft.

Those seeking a closer view of this off-limits zone can always reply to the job advert - although they should be warned that the selection process is likely to be rigorous.

As well as having a CV boasting "a minimum of 3,000 fixed-wing flying hours in-seat with 300 in-seat hours within last five years,", applicants "must qualify for and maintain a TS [top secret] government security clearance." Which will narrow the field a little. JANET's ploy of hiding in plain sight should be effective for a while longer.

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