The StarPort May Be the Ticket
by Jim Starry
by Jim Starry
Thousands of new airports are set to be built worldwide within the next
decade. An innovative design called the StarPort could produce fuel savings
of 300 million gallons a year at each airport, would require only one-third
of the land as a conventional facility and yield four times the revenue.
Worldwatch Editor Ed Ayers calls the StarPort design a "breakthrough...
a much more intelligent way of using techniques we humans have have had all
along.
Airports designed to handle 350 flights per day 30 years ago are now
scrambling to handle 700.
A mondern airport consumes nearly 500 million gallons of fuel a year -
nearly half as much fuel as burned by a large city's automobiles. But
because aircraft are not required to install catalytic converters, airports
are responsible for more than half of the local urban air pollution.
We have gridlock at most major airports, with more than 20 planes lined up
on runways waiting their turn to take off while washing enormous amounts
of partially burned fuel into the atmosphere.
The fumes from idling diesel jet engines are about 14 times more polluting
than gasoline exhaust. At many airports, levels of carbon monoxide,
hydrocarbons and nitrogen oxides are at least 10 times higher than in surrounding
cities. This isn't progress, its suffocation.
A boeing 747 jet consumes more than 500 gallons of fuel during taxiing - enough
fuel to operate a car for a year. One thousand taxi-to-takeoffs consume 12 million
gallons - sufficient to power 200,000 cars for a day. Only four percent of the fuel
burned goes into actually moving the aircraft. The rest is thrown to the wind as
exhaust and noise.
The sprawling 52-square-mile Denver International Airport wasbuilt to handle 2,000
flights a daily - a landing or takeoff every 20 seconds. Denver International offers
100 gates and five 12,000 foot (2.3 mile long) runways. The StarPort could save $200
million in fuel costs for an airport with the air traffic of Denver International while
cutting taxiing distances by 48 percent.
Gravity not Kerosene
The solution? The StarPort incorporates inclined runways that use gravity to help planes
slow down on landing and takeoff. Inclined runways would be shorter, requiring a
smaller footprint.
Planes taking off down an inclined runway would reach takeoff speed sooner, saving 1,000
gallons of jet fuel per flight. The runways would be slightly concave to help planes
stay centered. They would be wider at touchdown, narrowing as they approach parking gates
atop the terminal dome.
FAA officials have said it is against regulations to permit inclined runways but a number
of existing US airports already have sloped runways - Colorado's Telluride Airport is built
on a 4 percent incline.
In fact, FAA regulations do permit inclines up to 1.5 percent. It would be possible to design
a runway that starts at a 1 percent incline and slowly rises to a 4 percent grade.
Put on the Brakes
Regenerrative braking systems installed on electric cars not only slow down speeding cars,
they simultaneously transform the braking force into electrical energy that is stored in
batteries for later use. If lightweight, vertical armature electric motors were installed
in aircraft wheels, the tires could be pre-rotated before touchdown (eliminating damaging
structural shock and tread burn). From the moment the plane touches down, the tires could
begin generating electric power,. Combined with an inclined runway, they would eliminate
the need for noisy 30-second thrust-reversal engine burns that can easily burn 300 to 500
gallons of fuel for each landing.
The Subsurface Terminal
An incline of 2 percent would eventually lift a 6,000-foot-long runway 120 feet above the
surrounding landscape. The central terminal, where planes park and wait to take on passengers,
could tower as high as a ten-story building.
Most airport customers now endure a 1.5-mile trek from their cars to departure gates. At
many airports, this means that each day 200 passengers on 700 flights wind up walking
70,000 miles to build up their Frequent Flyer accounts.
StarPort passengers would board from below, moving almost directly to their aircraft
from a subsurface terminal in less than six minutes. For an airport the size of Denver,
this design would reduce the average travelers' curb-to-counter commute by 80 percent.
In addition to terminal space, the sub-terminal space would include several floors of
parking, restaurants, shopping, hotels, convention and meeting space.
Instead of circling a traditional airport and waiting in long lines to enter a single
entrance, the StarPort would have traffic entering and leaving the airport from four
directions.
Runways would be laid out side by side with 600 foot separation, allowing simultaneous
takeoffs and landings. Taxiing distances would be reduced 80 percent, with additional
fuel savings. Lights beaming upward from the terminal could serve as runway lights.
In winter, the terminal's heat would serve to melt ice and snow off the runways.
Major US cities are scrambling to find airport sites that meet a simple, but impossible,
description: "50 square miles of unpopulated land - close to downtown." A StarPort could
be built on only 15 to 25 square miles. Instead of turning valuable open space into new
mega-airports. StarPorts could be built at hundreds of smaller existing airfields that
were abandoned with the move toward larger aircraft and longer runways.
If the 2,000 new airports were StarPorts, the fuel savings would amount to two billion
gallons a day - more than 1,000 times the oil the Bush administration hopes to extract
from the Artic National Wildlife Refuge.