Cheaper "basic economy" airfares on American Airlines went on sale Tuesday from Philadelphia International Airport to five cities: Dallas-Fort Worth, Fort Lauderdale, Fla., and Miami, New Orleans, and Charlotte, N.C.

American, which operates a hub in Philadelphia and more than 400 daily flights here, is offering the new fares for travel beginning March 1.

The lower-tier tickets, which provide a basic seat on the plane and not much else, are being sold by American on 10 U.S. routes from its hub airports in Philadelphia, Dallas-Fort Worth, Miami, and Charlotte.

A check on American's website Tuesday showed a round-trip basic economy fare from Philadelphia to Miami was $178 compared with $218 for regular economy, leaving March 1 and returning March 8. A round trip between Philadelphia and Fort Lauderdale was $158 for basic economy versus $198 in regular coach economy, departing March 1 and returning March 8.

Basic economy tickets are not a lot cheaper —often $15 to $20 each way. (Ticket prices change constantly based on how full the plane is, the time of day, and the date of travel.)

With basic economy, passengers can bring one small item, such as a purse, a backpack, or a briefcase that fits under the seat. Anything bigger must be checked for a $25 fee.

Travelers can't select their seats in advance, and will board the plane last. Tickets are not refundable, and itineraries cannot be changed, even for a fee. Customers who do not make the original booked trip will forfeit the value of the ticket.

"The fare difference isn't worth paying a checked-bag fee and sitting in the middle seat," said George Hobica, founder of "Airlines are doing this to appear at the same price point in airfare searches on third-party sites, such as Orbitz or Travelocity.

"But is it a good value for consumers? No," Hobica said.

Travelers who choose basic economy trips will end up in the dreaded middle seat because other passengers will choose their seats, a window or an aisle, he said. "You are definitely going to get the middle seat. They should call these the middle-seat fares."

The major carriers — Delta, American, and United —are introducing the fares on select routes to attract price-conscious consumers who now choose to fly ultra-low-fare competitors such as Spirit, Frontier, and Allegiant airlines.

The basic economy prices in Philadelphia are on routes currently flown by Spirit or Frontier, whose business strategy is rock-bottom fares, but they charge extra for everything including a carry-on bag in the overhead bin.

The basic-economy tickets will not be available on every flight, and will be priced based on supply and demand, American said. "These routes were chosen because they provide a variety of competitive situations," American said. "Pricing and availability of basic economy will always vary based on supply and demand. This is the first phase, with more cities to come in the months ahead."

The new fares will be available only on nonstop, and not connecting, flights between Charlotte and Orlando, between Dallas-Fort Worth and Baltimore-Washington International, between Dallas and Tampa, between Miami and Tampa, and between Miami and New Orleans.

The discount carriers have been expanding and taking business away from the so-called legacy airlines. Frontier flies to 10 cities from Philadelphia International, and will add Houston and West Palm Beach, Fla., in March. Frontier flies to nine destinations from Trenton-Mercer Airport.

Spirit has seven daily flights from PHL and nine daily flights from Atlantic City airport. Allegiant Air flies to three Florida cities from Trenton.

Basic economy fares are in addition to regular economy tickets, and will not replace them. Rather, airlines are looking for new ways to lure customers and bring in revenue.

United Airlines announced later Tuesday that it has begun selling basic economy tickets on some flights from Minneapolis to seven of its hub airports including Newark, N.J.; Chicago, and Los Angeles.