American Airlines, a unit of AMR Corp. (AMR), expects to offer wireless Internet service to most domestic passengers over the next two years.

Doug Backelin, manager of inflight communications and technology, said American has successfully completed tests with Wi-Fi provider Aircell LLC, and this year will equip its fleet of 150 MD-80 aircraft with Gogo, a wireless ground-based Internet service. The carrier will add service on its Boeing 737-800 fleet in 2010.

Delta Air Lines, Inc. (DAL), which last year merged with Northwest Airlines, now has 77 aircraft with Wi-Fi capabilities. "Customers can expect to have Wi-Fi available on all pre-merger Delta domestic mainline aircraft late this year, and on pre-merger Northwest mainline domestic aircraft next year," said spokeswoman Betsy Talton.

UAL Corp.'s (UAUA) United Airlines said earlier this year it will begin offering the Aircell service on its transcontinental flights later in 2009.

Jack Blumenstein, chief executive of Chicago-based Aircell, said the company is working with a number of U.S. airlines and with Air Canada(AC.A.T), and plans to expand service across North America into Mexico. The broadband company places small antennae on aircraft to communicate with its ground-based network. Air passengers can access the service when aircraft are flying above 10,000 feet.

Aircell is also looking for ways to offer satellite-based wireless communication for ocean-crossing flights, but Blumenstein said that technology faces challenges to provide cost-effective full Internet access.

The airlines haven't commented on the economics of Aircell, which costs $12.95 for long flights. American's Backelin said the airline is investing "very carefully" in customer-friendly upgrades, and will share revenue with Aircell. The Aircell service allows customers to surf the Internet, use email, and access corporate Web sites, using laptops or handheld PDAs. American will offer wireless service for handheld devices at $7.95 per flight.

Some other airlines are offering onboard satellite television that includes a Wi-Fi option for sending email and instant messages.

-By Ann Keeton; Dow Jones Newswires; 312-750-4120; ann.keeton@dowjones.com