It's part of getting passengers, and their bags, on and off planes more efficiently.

About 900 US Airways Group flights come and go at Philadelphia International Airport each day, and those planes are serviced by ground equipment, like baggage tugs and catering trucks.

To improve getting bags to and from planes, and with less down time for equipment maintenance, US Airways on Friday opened a $22 million ground-service equipment shop at the west end of the airport in Tinicum Township.

The 56,000-square-foot building will handle repairs and upkeep on 770 pieces of motorized equipment and 1,200 other items that service US Airways' 435 daily departures - and a similar number of arrivals.

While it's not the stuff passengers usually see, except outside an airplane window on the tarmac, the ground-support operations of a major airline, such as US Airways in Philadelphia, "and the virtual nonstop required use of vehicles including baggage tractors and belt loaders has a direct impact on how well that airline is going to operate at the facility," Philadelphia airport CEO Mark Gale told a crowd at the building's grand opening.

"It also has a direct impact on the environment in terms of noise, air emissions, and air quality," he said.

The building is the latest addition to the airport's "green initiative," which includes 73 electric baggage tugs - and more are on the way - to replace older diesel-fueled vehicles.

"What passengers will see is more equipment out on the ramp, so that their bags get off the airplane sooner into baggage claim, or bags get from the ticket counter to the airplane on time," said Jim Brewer, manager of 90 employees, including 70 mechanics, at the new facility.

With a stockroom that incorporates advanced inventory control techniques, vehicles will be out of service for shorter periods awaiting parts, which will save time and money. A wash bay and paint booth will improve equipment appearance.

Nine inground lifts will elevate equipment, such as tugs that pull wide-body jets, at the touch of a button. Mechanics previously had to drag portable lifts to the vehicle, and plug one under each tire, before lifting it. The process took 20 to 45 minutes, Brewer said.

Aircraft maintenance is handled separately, in two US Airways hangars at the airport.

"Our equipment will be more reliable, and, therefore, our departures and arrivals will be more reliable," said Bob Ciminelli, head of US Airways' Philadelphia operation.

"Baggage will also be affected," he said, "by reducing maintenance down time for our ground-service fleet, such as baggage carts, which will help optimize our baggage delivery times."

Just a few years ago, US Airways' Philadelphia operation was plagued by delayed and lost luggage, malfunctioning baggage conveyor belts, and decrepit equipment that made its baggage delivery among the worst in the industry.

Since then, US Airways has added people, equipment, training, and new top management in Philadelphia with an emphasis on improving customer service - and getting luggage to and from planes faster.