The set features an airport with satellite equipment and a schedule for flights, a cargo helicopter with two rotors, both on top, another helicopter with two rotors, one on top and one on the side of the tail, a passenger plane, a baggage handler, a forklift, and twelve Minifigures. This set changed to new LEGO City package in 2005.
This set is a re-release of 6597 Century Skyway from 1994. However, there are with some differences in the building parts between 6597 and 10159, such as the window glass and the base plate.
This is a description taken from LEGO.com. Please do not modify it.
Take to the skies!
There's adventure in the air at the City Airport! The classic set was first produced in 1994 and is a bustling as a real airport. Check the schedules and book your flight, then taxi down the runway on the speedy passenger jet. Watch the forklift load cargo onto the helicopter on the nearby helipad. You'll find everything you'd see at a real airport, from a rolling baggage cart to a refueling car. Includes air traffic control tower, 12 minifigures and other accessories!