FORT LAUDERDALE, FLA. — Spirit Airlines ceased flight operations last weekend and its lawyers have filed in court seeking permission for an orderly wind-down, including the return of leased jets and the monetization of remaining aircraft and other assets. The carrier left more than 90 planes at dozens of airports around the country when service stopped.

According to court filings, more than 60 planes in Spirit's active fleet were leased, accounting for nearly two-thirds of its operating aircraft, and the lessors want those planes returned. Spirit has 28 Airbus A320 family planes available for sale, along with engines, spare parts, gates, landing slots, real estate and other assets available for liquidation.

A few Spirit planes were repositioned, including Nomadic Flight 189 from Fort Lauderdale to Phoenix Goodyear Airport, which traveled with only a skeleton crew and no passengers for storage in Arizona. Nomadic Aviation Group, which works with six of the companies that own Spirit's jets, is sending qualified pilots, including former Spirit pilots, to fly the planes. Those pilots often wear jeans and t-shirts rather than airline uniforms and sometimes encounter resistance when attempting to repossess aircraft.

"Everybody tries to move them as quickly as possible," said Steve Giordano, managing partner of Nomadic Aviation Group. "Some are already probably in the pipeline to be leased again. Some are going to have the engines removed, moved on to different airframes and those aircraft are going to get leased."

Giordano said in a podcast interview that pilots sent to retrieve aircraft routinely meet pushback from airport personnel. "You go up to a person of authority and say, 'I need to get on that airplane, I'm repossessing it.' And the first thing they're going to say is, 'no, no, no, no, no.' They're going to call out the sheriffs, the airport police, the airport managers," he said.

Spirit holds takeoff and landing slots at LaGuardia Airport and Newark Liberty International Airport. Ahmed Abdelghany, professor of operations management at Embry-Riddle Aeronautical University, said the slots will draw demand. "You can easily sell slots at those constrained airports, and many airlines will be in line to buy them," he said.

Henry Harteveldt, airline analyst at the Atmosphere Research Group, said fuel costs complicate the asset sales. "One of the challenges for Spirit and its creditors is that the high cost of jet fuel makes many of Spirit's planes less appealing to acquire," Harteveldt said. "I think the airline will find buyers. It just may be a slower selling cycle than had this happened a few years ago or even just like, say, three months ago."