(Adds link to story on Irma in second paragraph)

By Andy Sullivan and David Shepardson

Sept 7 (Reuters) - Airlines were racing against the clock to clear as many customers as possible from the likely Florida path of Hurricane Irma, as social and political pressure mounted for carriers to play a bigger role in aiding evacuations.

As the powerful storm threatened to rip through the Florida coast by Sunday, airlines ramped up the number of flights available out of south Florida airports, where operations were likely to temporarily cease through the weekend and beyond.

But flights out of the area remained extremely limited. At Miami International Airport, many outbound flights were canceled, leaving residents scrambling to rebook to anywhere outside the path of the storm.

American Airlines, which has one of the larger operations in south Florida, said on Thursday it had added 16 flights out of Miami, amid more than 2,400 forced cancellations through Monday.

Delta Air Lines Inc said it had upsized aircraft and added flights to increase the number of available outgoing seats by 2,000. United Airlines added six flights out of Miami to its hubs, including Newark, New Jersey, and Chicago O'Hare.

All three carriers said they planned to mostly wind down south Florida operations by Friday evening.

In areas already pummeled by the powerful storm, flight operations had been rolled back and halted altogether.

A Delta-operated flight from New York to San Juan, Puerto Rico, and back, made headlines for narrowly avoiding the storm in a mission to evacuate another plane-full of passengers from the area ahead of Irma's landfall.

Flight-tracking website FlightRadar24.com saw the plane land for one last departure in the U.S. territory located squarely in the path of Irma's landfall, fill with passengers, and make its successful flight back to New York on Wednesday. Other airlines had already ceased operations in the region.

PRICE-GOUGING

As residents sought to secure last-minute flights out of the dangerous Category 5 storm's path, airlines faced accusations of trying to capitalize on the panic and chaos by price gouging.

Under pressure from some members of Congress following social media reports, airlines have taken the unusual step of publicly announcing price caps on tickets out of areas in Irma's course.

Early on, carrier JetBlue capped flights out of the area at $99, and other carriers followed suit, capping fares at between $99 and $399 a ticket.

But while airlines offered some cheap flights out of south Florida after complaints, passengers said that did little good if all the flights were fully booked or canceled.