Spirit's CEO said no talks were scheduled with picketing pilots, and a union leader said the pilots "will not return to the cockpit until a fair and equitable contract is negotiated."
The privately-held airline based in Miramar, Fla., carries 16,680 passengers per day - about 1 percent of the U.S. total - mostly between the eastern U.S. and the Caribbean and Latin America. But its shutdown is causing major problems for its flyers.
Spirit tickets are only good on a handful of other carriers, and only if there's space on the flight. The airline said it was refunding fares for Saturday and Sunday flights plus a $100 credit toward future flights. It was trying to get its passengers booked onto other airlines.
People who needed to replace their Spirit tickets found the cost of same-day fares on other airlines was two- to three times more than their tickets.
That was out of the question for Junior Elliott, a 67-year-old mason from St. Ann's parish in Jamaica, who was stranded in Fort Lauderdale while traveling to New York for a cousin's funeral.
Elliott was unable to buy new tickets until his fare was refunded to his debit card. He had no cell phone, no U.S. currency, and nowhere to sleep but the terminal's seats.
"It's bad now, man," Elliott said. "I can't even buy a cup of coffee."
Fort Lauderdale-Hollywood International Airport is Spirit's main hub, where it is the only airline to 14 international cities and five U.S. destinations, airport spokesman Greg Meyer said. Around the country Spirit runs roughly 150 flights per day.
The Spirit terminal, usually the busiest in Fort Lauderdale, was full of angry travelers desperate to return home or start trips on Saturday. Extra Spirit staff and local police officers were posted in the ticketing area.
Spirit CEO Ben Baldanza said in an interview that he hoped to get some of Spirit's 31 aircraft flying soon with management pilots or others who cross the picket line, but that no such flights took place on Saturday.
He said Spirit has lined up one airplane from another air carrier - he declined to say which one - to complete a few flights. He was hoping to add other carriers in the days ahead.
Spirit pilots have said their pay lags behind competitors such as AirTran Airways and JetBlue. The airline and its pilots had been negotiating for more than three years.
Pilots "are sacrificing our paychecks until we get a contract that reflects our contributions to this airline," Sean Creed, a Spirit captain and head of its Air Line Pilots Association unit, said in a statement on the union's website.
Spirit has about 440 active pilots.
Airline analyst Vaughn Cordle said Spirit pilots made more per hour of flying in 2009 in wages and benefits than AirTran pilots, but less than JetBlue.
Baldanza said that Spirit has made money over the past year and a half. He said he knew its pilots would need raises.
The company offered to raise pilot pay by 30 percent over five years, although work rule changes mean pilots would have to fly more to earn that money.
Spirit's offer also kept a four-day break between every pilot trip, something the company said no other ALPA contract has. The offer also included a $3,000 signing bonus and a larger retirement plan match.
The strike is being closely watched in the industry because pilots at much larger carriers, including AMR Corp.'s American Airlines, are also locked in tough negotiations.
The last strike at a major carrier was in 2005, when Northwest Airlines mechanics walked off the job rather than accept deep pay cuts. The strike failed after Northwest replaced them.