Starting Saturday, customers can book the flights at usairways.com or aa.com. The Charleston flight will be once a day, except Saturday, on 37-seat Dash 8 aircraft.
The Memphis and Lexington flights will operate three times daily on 50-seat regional jets. All will depart and arrive out of the airport's Terminal F.
By the end of the year, American plans to take delivery of the airline's first Boeing 787 Dreamliner. American has placed firm orders for 42 Boeing 787 Dreamliner aircraft, with the right to acquire an additional 58. The first two aircraft will likely go into service early next year, said airline spokesman Todd Lehmacher.
Philadelphia officials and the city's hospitality industry would be keenly interested in Philadelphia getting the 787, which would seat up to 330 passengers and be capable of long-haul routes to Asia.
"We just don't know yet. That analysis continues, but the plane potentially opens up new routes out of cities like Philadelphia," Lehmacher said. "That's the million-dollar question everyone wants to know: Where are we going to put those aircraft?"
In 2007, US Airways announced to great fanfare that it would begin a nonstop route between Philadelphia and China, starting in 2009.
But after financial markets crashed, oil soared to $147 a barrel, and the economy plunged into recession, US Airways scrapped the China route. At the time, the airline said it would need to lease or buy more long-range Airbus or Boeing jets capable of flying nonstop to Asia.
American's announcement Thursday to fly nonstop from Philadelphia to Memphis comes as Delta Air Lines, based in Atlanta, has cut service in Memphis, formerly a hub for Northwest Airlines. Delta went from 94 to 64 daily flights in Memphis last June. Delta now flies 47 flights a day at Memphis and has trimmed its Memphis-Philadelphia flights from twice a day to once a day.
Joe Taney, vice president in charge of the US Airways-American Philadelphia hub, said Thursday that the added service to key cities in Kentucky, Tennessee, and West Virginia highlights "American's ongoing commitment" to Philadelphia.
When the flights begin in June, American and US Airways will serve 127 destinations in 25 countries from Philadelphia, Taney said.
Scott Brockman, president and CEO of the Memphis-Shelby County Airport Authority, said in a statement that the new nonstop options show that American and US Airways "see opportunities in the Memphis market."
"Nonstop flights to Philadelphia also bring added value to Memphis by providing one-stop connecting flights to the many international cities served out of American's Philadelphia Gateway," Brockman said.
American Airlines Group opened a new American Airline Admirals Club on Monday in Philadelphia airport's Terminal A-East (between Gates 4 and 6), which brings to four the number of US Airways and American lounges at Philadelphia airport for frequent fliers who pay to use airport clubs while waiting for flights.