"Janet" is the radio call sign of a private airline operated by EG&G, which shuttles workers into Area 51 from Las Vegas. The planes are mostly white Boeing 737's, with a red stripe on both sides. They can be seen at Las Vegas International Airport (KLAS), where the Janet airline has its own high security terminal in the northwest corner of the airport.
The Las Vegas Janet terminal is located in a fenced-off area in the northwest corner of Las Vegas International Airport. It is surrounded by a large parking lot, with approximately 1620 marked parking spaces, which is usually more than 2/3 full on any given workday.
For more information click here.