Q. How does low-speed maglev technology work?

A. Maglev technology employs powerful superconducting magnets to levitate or "float" cars about 2 inches above a guideway. Liquid helium in a special encasement cools the magnets to near absolute zero (or about -400 degrees Fahrenheit), enabling relatively small magnets to create very powerful fields.

Linear induction motors using magnetic fields propel the cars. Such motors are already adapted to transit, such as in Vancouver’s automated SkyTrain Light Rail system.

Electrodynamics involving the interaction of electrical currents and magnetic forces, state-of-art computers and microprocessors maintain guidance (vertical and horizontal spacing) during travel. Low-speed maglev travels up to 60 mph. In Pittsburgh’s case, top speed will be about 40 mph.

A. It’s a matter of complex physics. But by bathing superconducting magnetic coils in liquid helium, a refrigerant, scientists can create large magnetic fields that produce no electrical resistance – they don’t lose power and they use very little energy. "It happens almost like magic," one scientist said.

A. Nowhere. One built in the mid-1980s in Birmingham, England, operated until about three years ago. It used a since-abandoned technology and consisted of a single-car, 2,000-foot shuttle between a parking lot and an airport terminal.

Once hailed as a step into the future, the Birmingham maglev was replaced by shuttle buses. Supporters claim the system was never properly maintained or updated with technology that has since improved.

A. There are three phases, each one linked with 5,000 spaces of parking intended to generate money that the builder, Western Pennsylvania Maglev Development Corp., said is necessary to offer free rides, pay for electricity and provide adequate maintenance.

WPMD wants to get the first phase under way soon to showcase the technology and set the stage for two extensions. The first project is called Civic Arena Shuttle System.

CASS would consist of an elevated, 2,200-foot dual guideway, 30 feet above the ground, connecting a parking garage behind the Civic Arena to the Sixth Avenue-Ross Street entrance of the Steel Plaza subway station Downtown. The cost of CASS is estimated to be $147 million, all of which WPMD is trying to raise privately, although public bond guarantees would be required.

Two proposed extensions from CASS, requiring at least 50 percent government financing, are referred to as Pittsburgh Airborne Shuttle System. One extension would run to the North Shore and the Gateway Center T Station. The other would run to the Pittsburgh Technology Center and Oakland. There would be 16 stops on a fully built, 10-mile system at places such as Carnegie Mellon University, University of Pittsburgh, Duquesne University, a new convention center, North Shore stadiums and Carnegie Science Center.

Total cost of all three phases, including the parking garages, has been estimated at $700 million.

A. Supporters cite lower capital costs, lower operating costs, tight turning capabilities, virtually no noise pollution, smooth rides because levitated vehicles create no friction, less intrusion on land and an opportunity to showcase the city and establish it as world leader of transit technology.

Critics of the Pittsburgh project are questioning the use of public money, the philosophy of building the largest parking garage in Pittsburgh near Downtown rather than on the outskirts, competing with the Port Authority for funds and riders and whether any short transit system to the Civic Arena serves a worthwhile purpose.

Q. How does CASS compare with the people mover at Pittsburgh International Airport?

A. They’re both shuttle systems that offer rides of similar time, distance and comfort in cars that virtually look alike.

The technology is not only different, but the Civic Arena maglev would operate outdoors instead of underground; on a 7 percent grade instead of on level; and encompass a 250-foot turn instead of a straight guideway like the people mover.

A. If there’s a real emergency, riders could open car doors manually to reach a combination emergency/maintenance walkway between the parallel maglev "tracks."

The maglev plan proposes using a customized tow vehicle in case a car dies because of lost power or a mechanical problem. It could go out on the track to push or tow a crippled car. Meanwhile, maglev would maintain service on the opposite track.

Maglev cars are to contain recessed emergency wheels, so if the cars lose their levitation, they can still ride on the guideway. Plans for the Civic Arena showcase project call for building a third maglev car to use as a spare.

A. Not likely. Ice and snow don’t affect superconducting magnets or linear induction motors. The guideway will be designed with angles so most snow falls off or through holes that also allow natural light to penetrate below. If there’s an accumulation of snow, the tow vehicle mentioned above can be equipped with a snow plow and a rotating broom to clear the path.

A. Just as a light rail vehicle uses a Z-shaped pantograph to collect electricity from overhead wires and transfer it to the car, maglev will use an armlike device to collect power from a small "power rail" incorporated into guideway construction. Lower voltage power used for car doors, lights, heating, ventilating and air conditioning is created through the use of transformers.

A. Western Pennsylvania Maglev Development literature states a new maglev industry would create up to 4,000 jobs, a figure that people interviewed for this article thought to be too high.

They said the employment outlook, not counting temporary construction jobs, would more likely be in the hundreds, depending on whether maglev were sold elsewhere and on how many Pittsburgh businesses would be involved.

For example, General Atomics officials said it would need only 16 people total "from the first day for testing, programming and building" the system, including the superconducting magnets. "I don’t know where [WPMD] came up with those figures" about 4,000 jobs, GA project manager Eddie Leung said.

A. Since low-speed maglev cars are one-sixth the weight of high-speed maglev and since magnetic coils don’t have to be imbedded in the guideway, the much lighter elevated dual guideway can be built on T-shaped concrete columns 3 feet in diameter.

Columns would be up to 120 feet apart on a straight-away. They could be built within the area of a single parking space if the elevated system were to be built on a busy street such as Fifth Avenue. That is partly why supporters say maglev would be a perfect fit in Oakland.

A. WPMD points to a consultant’s parking and marketing study that shows at least 20,000 people will soon be working a short distance away on Grant Street, at places such as Mellon Bank and the USX Tower, whose 575 parking spaces are usually filled despite a $17 charge after two hours. Also, parkers using the Civic Arena surface lots, which could be used for development, could be attracted to the new facility. The present 15-minute walk Downtown could become a 72-second maglev ride.

WPMD said the parking garage would generate enough revenue to meet bond payments and expenses with 3,500 to 4,000 all-day parkers.

WPMD also is looking to "double load" the garage, meaning in addition to daytime commuters, the garage would be used nights and weekends for Civic Arena events (137 events last year).

Will drivers who now pay $4.50 for all-day parking at the arena pay the $11 all-day rate that WPMD plans to charge? A consultant, Wilbur Smith Associates, believes so. An "event rate," now $8, has not been established.

Q. How would the extra cars affect traffic around the Civic Area.

A. WPMD points out that there will be a total of 14 entry-exit lanes, some fitted with high-tech EZ-Pass-type equipment to automatically deduct parking fees from pre-paid accounts.