PHILADELPHIA >> Don’t buy tickets quite yet for a luxury sail on the SS United States.

Plans to return the historic ocean liner to the high seas are being abandoned for a second time after a cruise company concludes it’s not feasible.

Los Angeles-based Crystal Cruises will instead make a $350,000 donation to the conservation group that owns the ship, which has been sitting idle at a Philadelphia wharf for two decades. The company had pledged to spend at least $700 million to return the ship, which is bigger than the Titanic, to its glory days as a luxury ocean liner. But the task proved too great, even though they found the ship structurally sound.

“Unfortunately, the hurdles that would face us when trying to bring a 65-year-old vessel up to modern safety, design and international regulatory compliance have proven just too great,” Crystal Cruises President Edie Rodriguez said in a statement.

Norwegian Cruise Lines announced a similar overhaul in 2003, hoping to put the SS United States in service in Hawaii. But those plans did not materialize for similar reasons.

Susan Gibbs, executive director of the conservancy, said the ship could still be turned into a waterfront attraction, perhaps with a museum component, in New York or elsewhere.

In the 1950s, the ship carried everyone from royalty to immigrants across the Atlantic Ocean, accompanied by three on-board orchestras. It was the biggest and fastest ocean liner that had ever been built in the United States at the time.

On its maiden voyage in 1952, the liner crossed the Atlantic in three days, 10 hours, 42 minutes, a record that stood until 1990. The ship was decommissioned in 1969.