LOS ANGELES, Feb. 4 /PRNewswire-USNewswire/ -- A series of federal lawsuits filed this week in Colorado and California allege that United Parcel Service has been improperly charging high air-transportation rates for next-day and two-day deliveries that were actually sent by far-cheaper ground transportation.

According to the suits, UPS has been deliberately transporting some customers' "Next Day Air" and "2nd Day Air" packages by ground rather than by air and billing customers for the more expensive air shipping option. The suits assert that UPS has even named the practice internally: the "Air-in-Ground" program.

"Despite UPS's agreement to provide (and accept payment for) air shipping services, UPS has been systematically and deliberately substituting far less expensive ground shipping services, and UPS did not disclose to customers that they were paying for air services they never received," the suits state.

The suits add: "UPS has engaged in an organized and nationwide campaign to identify all air deliveries that feasibly could be diverted to ground without missing the delivery deadlines, and has rerouted those packages for ground delivery whenever possible, all without customers' knowledge or consent.  UPS has been charging Class members a steep premium for 'air' services it never provided and never had any intention of providing.   This wrongful practice is known internally at UPS as the 'Air-In-Ground' program."

The complaint also alleges that UPS has assessed customers a fuel surcharge based on the cost of jet fuel when the customers' packages were sent by ground and were never on a plane. The suit adds that UPS knows about such diversions and does not inform its customers.

According to the suits, UPS has charged customers potentially hundreds of millions of dollars in unwarranted fees.  UPS customers who have shipped packages via "Next Day Air" fewer than 400 miles or via "Second Day Air" less than 600 miles may well have been overcharged thanks to UPS's Air-In-Ground program, the suits say.

A suit making these and other allegations was filed in the U.S. District Court in Denver on behalf of a car dealership. Similar suits were filed in the U.S. District Court in Los Angeles on behalf of an importer and a food company.

The plaintiffs have established an informational website at www.upslawsuit.com.