StarPort airports use gravity to save on fuel

An environmental designer in Oakland, California is advocating a radically new way of designing airports that is projected to save 2 billion gallons of jet fuel a day.
In the StarPort concept by Jim Starry, airports would be designed as a large mound, with a flat top that serves both as an apron and as the roof of the terminal buried below. Off the sides of the mound are inclined runways.
Incoming aircraft would land on an upward sloping runway, thus using less fuel to break. Outgoing aircraft use the downward slope and use less fuel to accelerate. Starry estimates that by using gravity’s benefits in this way, a typical Boeing 747 would save about 1,000 gallons per flight.
StarPorts would be compact — only 25 square miles compared to 50 square miles — thus saving commuter gasoline and building sprawl.
Because the StarPort’s airside facilities — landing and parking bays, control tower, etc. — would be on top of the terminal, there is another environmental benefit: rising heat from the terminal would eliminate the need for de-icing the planes parked on top.
Source: Utne Reader, May-June 2003.