(FORTUNE Magazine) – Ali, the front-desk clerk at the Robert Treat Travelodge Hotel, is evasive when FORTUNE asks him which floor the flight attendants are staying on. "Oh," he says, "I can't give out that information." Within minutes of checking in, it's obvious that FORTUNE doesn't need his help. The place is crawling with flight attendants, pilots, and mechanics. They, in fact, account for 30% of the business of this budget hotel in downtown Newark, N.J., 15 minutes away from its international airport.

This hotel is just one of many across the country that appear to the world to be regular hotels but are known among airline employees for having several floors set aside for "crash pads." Hotel crash pads give airline crews a low-cost place to sleep when they're between flights and far from home; a few are also prime venues for world-class partying.

The Robert Treat Travelodge falls in the world-class-party category. It's legendary. At the "Treatment Center," as the hotel is called, groups of up to 17 airline crew members chip in about $85 each per month for part-time shares in single-sex or coed rooms jammed with bunk beds. Most of the 12th floor of the hotel is blocked out for use as crash pads. "Up on 12 we're a big family," says a lissome blonde flight attendant whose resemblance to MTV's Jenny McCarthy allows her to moonlight as a TV extra. "A big incestuous family."

As the elevator doors slide open on 12 with a gentle ding! FORTUNE's nostrils are assailed with the scent of a fraternity house on a Sunday morning. Its residents are sprawled on the floor of the hallway, indulging in an assortment of jet-set bijoux picked up around--or above--the globe: French wine, fancy cigars, and tiny bottles of Bailey's Irish Cream that everyone swears weren't pilfered from an employer's drink cart. Conversation centers on who will be in which city 24 hours from now, and where they'll go to get sloshed after they land. The mostly male pilots and mechanics seem less interested in drinking per se than in its effect on the employees formerly known as stewardesses. FORTUNE takes in the scene while giving a member of the latter group a foot massage.

Once the hallway has filled with cigar smoke, the party moves up the "Stairway to Heaven" (a pilot explains that there's no privacy in the rooms, so the hotel's stairwell is where late-night rendezvous tend to happen) and on to the rooftop lounge. The most popular area of the Treatment Center, the rooftop lounge is the site of an occasional game of strip poker and, during the summer, nude sunbathing. This evening on the roof there's a party being thrown by a group of Puerto Rican policemen who are in town for a convention, and who are not shy about asking the flight attendants to salsa.

As the hours roll by, almost all the flight attendants peel away from their dance partners--after all, there's no denying that having to get up at 4 a.m. to catch a transatlantic flight is a darn good excuse for calling it a night. By 2:30 a.m. the women are gone, leaving FORTUNE on this rooftop above the broken city of Newark with a six-pack of Bud and a cluster of downtrodden male flight attendants. --Ed Brown