BETWEEN midnight and 4 a.m., Memphis International Airport is the busiest airport in the world. More than 100 planes land here at the Federal Express ``Superhub'' before 2 a.m. every weeknight and then take off again by dawn.
At 11 p.m., a steady stream of bus headlights illuminate the night, shuttling an army of 5,000 employees from parking lots to the main hub building. Masses of people file quickly through a bank of metal detectors and head out for five hours of unloading incoming packages, sorting, and reloading.
Tonight, 106 aircraft are expected to bring in 1,112,000 packages - all expected at their far-flung destinations by 10:30 tomorrow morning.
The Memphis Superhub serves 93 airports. Several hundred more are serviced by smaller hubs in Indianapolis, Los Angeles, Newark, N.J., Oakland, Calif., and Anchorage, Alaska. But 65 percent of all FedEx traffic - 1 million to 1.5 million packages a night - travels through Memphis. That number can jump to 2 million at peak seasons, such as just before Christmas. ``Our record is 2.2 million packages in a 24-hour period,'' says John Harter, an employee who usually works on the Tarmac loading planes but occasionally doubles as a tour guide.
Planes start arriving on the three runways around 9:45 p.m., landing at a rate of one every 90 seconds until just after 1 a.m. The sort begins at 11:45 p.m. and ends at 2:07 a.m.
A nonstop blur of action
At midnight, the 295-acre Superhub is running at full tilt. Luggage carts blow their horns at every corner, forklifts dart in every direction, and employees hustle to unload planes. The nonstop blur of fast-moving conveyor belts increases the hectic atmosphere.
The Superhub contains more than 171 miles of conveyor belts - the main vehicle for getting packages through the sorting process. With the help of 250 video cameras, workers in the main control room monitor the conveyors for package jams. As soon as a jam is spotted, they can switch belts off from the control room and dispatch one of 50 ``jammers'' who carry radios and roam the Hub dislodging package pileups. ``Normally it's the smallest box of the bunch that causes the jam,'' Mr. Harter notes.
At the command and control center, employees oversee the logistics of coordinating a fleet of more than 400 airplanes and thousands of trucks. Computer monitors outnumber people here by at least 5 to 1.
Next door, the meteorology department is staffed 24 hours a day. Meteorologist David Mack and his colleagues forecast weather for 165 regions twice a day, keeping a particularly close eye on the company's hubs.
Pilots getting ready to fly out for the night mill around nearby looking at flight plans. Before getting into the cockpit, these pilots will check in with Mr. Mack for details on any weather problems in their flight paths.
``Lightning can force crews off the runways, so we have sophisticated equipment to track lightning,'' Mack says.
But tonight it is clear in Memphis and the Big Sort is on schedule. As the planes arrive, teams of 25 to 30 employees snap into action. Containers are quickly off-loaded from the plane's gaping belly. ``It takes about 20 minutes to unload most of our planes,'' Harter says.
The company advertises the fact that it can track your package every step of the delivery process. This is accomplished through bar-code technology. Each package is scanned a total of six times: on initial pickup, three times during the Hub sort, on arrival at the destination airport, and for final proof of delivery.
In the preliminary unloading process, packages under 70 pounds are put on a conveyor belt leading to the ``primary sort.'' Heavier packages are delivered by luggage carts.
And letter packets - the familiar paper-size sheaths - are sent to a separate area where they are hand-sorted and boxed by destination states in groups of 50 to 75. The boxed letter packets are then sent through as a single package.
Boxes on the move
A steady flow of packages cascades down a sloping ramp into the ``primary sort'' area. A Dell computer whizzes by, then an order from L.L. Bean and a box of grapefruit. The packages jostle and shove for position in line.
Workers at the ``primary sort'' turn the packages right side up so the routing numbers can be electronically scanned. Two electronic eyes measure the package length and then trigger one of 26 diverters at the precise moment necessary to kick the package down the proper chute to its ``secondary sort'' area.
From a catwalk above the perpetual motion, all this looks like a life-size game of Chutes and Ladders. Packages pour down one large chute and funnel through the electronic reader; metal diverters fire at irregular intervals, sending a package slithering down to a hidden destination in this seemingly endless maze.
At the ``secondary sort,'' packages are scanned for the correct city, state, and ZIP code. After a final check, they are loaded into containers and transported to planes.
At 1:30 a.m., a monitor shows that ``ALL FLIGHTS ARE HERE AT THIS TIME.'' About an hour after the sort ends, planes begin to take off. From 3 a.m. to 5 a.m., the Memphis sky is filled with purple and orange planes scattering in all directions.
``We launch East Coast flights first because they are losing time that direction,'' Harter explains. ``West Coast flights are held a little later because they are gaining time.''
There is little room for error in this operation. Emergency generators are on standby at all times, and every plan has a backup. Nine extra aircraft are available each night to replace malfunctioning planes or to fill in if unexpected volume comes through. Everything at the Superhub has a spare, in fact. A crew of 800 works nightly on aircraft and hub maintenance. All repairs are designed to be done in little more than five minutes.
``Everything is built with ease of access and the ability to change it out quickly,'' Harter says. ``What we do here in Memphis really impacts the whole system. So if we have a bad night here, they feel it everywhere else in the morning.''