Environmental regs, unique "cargo" present special challenges for bus fleets.
Talk about just-in-time delivery. Getting kids to school on time - and safely - is the responsibility of every school-bus fleet throughout the U.S.
"You can imagine the challenges we face in our maintenance program," says Bob Nagele, maintenance manager for the School District of Philadelphia.
One of the problems is that the fleet doesn't operate year-round. It's active 250 days a year - and then only for morning and afternoon pickups and deliveries. So attracting and retaining qualified drivers is a real challenge. Plus, every bit of cargo is a walking, talking report card on the driver's abilities and performance.
"The buses travel many miles a day on busy city streets, but we can minimize obstacles by specifying the right equipment," says Nagele. "When some of our buses gave us maintenance and ride quality problems, we changed our specs." New buses, for example, are now equipped with Hendrickson ParaSteer front and HAS rear air suspensions. "The front air suspension makes a big difference in comfort and steering performance," Nagele explains. "Ride comfort is critical for school buses because it helps keep good drivers and promotes safer driving." And if kids are comfortable, they'll behave better, he adds, keeping drivers happy.
The suspensions also keep the maintenance department happy. "A good performing air ride protects a bus from the harmful effects of road shock and vibration," says Nagele.
Environmental compliance is another pressure point for bus fleets that do in-house maintenance. Liberty Lines, a private bus fleet based in Yonkers, N.Y., handles most maintenance in-house, including grinding worn, cast-iron brake drums back to spec. In the process, cast-iron drum dust is produced that can float throughout the shop.
Since most of the dust is produced when the cutting tool is applied to the brake drum, supervisor Bob Tyra installed five source capture arms to provide suction right at the grinding points.
Many bus fleets also find themselves at the center of the alternative-fuels maelstrom. The federal mandate for lower levels of exhaust emissions means that fleets now have new issues to consider when deciding what kind of fuel to use: vehicle range, refueling; conversion costs; and performance.
Takoma, Wash.-based Pierce Transit has converted 58 of its 193 buses to CNG. Capital costs run $30,000 to $50,000 more than diesel counterparts, primarily because of the higher cost of CNG engines and natural gas storage cylinders, according to maintenance director Ron Shipley. Pierce also built an $847,000 CNG fueling facility. And maintenance facility upgrades such as enhanced ventilation systems and natural gas detectors added another $500,000.
Shipley reports that maintenance costs for diesel and CNG equipment are nearly identical. "There are still problems with the ignition system, specifically spark plugs and wires," he says, "but electronics are making the engines more reliable, which translates into lower maintenance costs."
Shipley reports that CNG engines are about 20% less fuel-efficient than their diesel counterparts. He attributes this to the lower compression ratios and throttling losses of the CNG engines, plus the extra weight inherent in the fuel tank system
FHWA last month proposed three rules for businesses that operate small buses or vans involved in interstate commerce. The rules would apply to businesses operating vehicles for hire, and designed or used to transport between 9 and 15 passengers, including the driver. Companies would be required to:
* Complete a motor carrier identification report so that FHWA can determine the number of companies currently operating, drivers employed, and vehicles in operation;
* Mark their vehicles with ID numbers assigned by FHWA; and
* Maintain records on crashes.
