Road warriors: Engineering researchers refine truck designs to meet ever stricter fuel-economy targets

摘要

They're celebrated in country music, deliver nearly 70 percent of all domestic freight, and log more than 100 billion miles each year. Forget Americas love affair with the car. Trucks -especially heavy-duty Class 8 haulers - remain king of the road. And that poses a problem as environmental and health concerns drive regulators to seek stricter limits on greenhouse gas emissions.