The inevitable has happened: Passengers who were onboard the ill-fated Triumph cruise ship have sued Carnival Corp.

The Triumph set sail from Texas for a four-day Caribbean trip on Feb. 7. But three days into the voyage, an engine fire caused the ship's propulsion system and power to go out—meaning the ship was at a standstill with no electricity, air conditioning, working kitchens or toilets. The 3,143 passengers and 1,086 crew members fought for food and sleeping space among unsanitary conditions. The ship was finally towed back to port on Valentine's Day.

It didn't take long for passengers to contact their lawyers—and now, the first suits are trickling in. Last week, two Triumph passengers filed the first class action against Carnival related to the debacle. Matt and Melissa Crusan of Oklahoma, suing on behalf of all other passengers, sued Carnival in a district court in Miami, claiming “Carnival knew or should have known that the vessel Triumph was likely to experience mechanical and/or engine issues because of prior similar issues” the ship experienced on voyages in mid-January, the court filing said.

Meanwhile, Carnival is still facing litigation stemming from the Costa Concordia shipwreck last year. In that mishap, the ship's captain steered too close to shore, causing the ship to capsize. The accident killed 32 passengers and crew members.

Read more InsideCounsel stories about Carnival's recent legal troubles: