The parents of a young man who died this week in a helicopter crash in New York City are suing the aircraft’s owner and operator, saying the company’s negligence resulted in their son’s death.

Twenty-six-year-old Trevor Cadigan, a former video journalist for Business Insider, was among the five people who were killed Sunday evening after a helicopter plunged into the frigid waters of the East River near Roosevelt Island, between Manhattan and Queens. The passengers had boarded the open-door helicopter for a half-hour ride above New York City, but the aircraft crashed just 11 minutes into the trip.

The helicopter had just flown over the Statue of Liberty and the Brooklyn Bridge when it began descending quickly toward the river. Videos captured by witnesses showed the helicopter capsizing and tilting onto its side, its rotor blades still spinning in the water. Only the pilot, who managed to free himself while underwater, survived.

The deaths have led to scrutiny over open-door helicopter tours that experts say allow even novice riders to board helicopters without proper training.

The lawsuit alleged that the aircraft owner and the company that runs the helicopter tours, which cater to tourists and amateur or professional photographers, have made it impossible for untrained passengers to free themselves in emergencies. Because the ride was an open-door flight, passengers wore tight harnesses that are connected to a metal ring across their back and tethered to the floor. Removing the harness during emergency situations required a type of training that Cadigan and the other passengers didn’t have, said Gary Robb, a Missouri-based helicopter crash attorney who represents the family.

“The family is simply shocked and outraged that their son drowned to death in this manner in what was supposed to be a pleasurable sightseeing helicopter tour,” Robb said in a news release. “If this had been a normal closed-door flight with normal safety belts, it would have been easy for Trevor to have unbuckled himself and for him to swim to the surface.”

Robb added: “You would have to be Houdini to escape in that situation. It was truly a death trap for him to be hanging upside down in frigid water temperature tightly harnessed with the release inaccessible in the back and no advance training.”

Liberty Helicopters, which owns the aircraft, and FlyNYON, which runs the helicopter tours, are named as defendants in the lawsuit. Both are based in New Jersey.

“We are deeply saddened by the loss suffered by the family of Trevor Cadigan and will continue to work closely with the government authorities in their investigation of the accident,” FlyNYON said in a statement Wednesday.

Liberty Helicopters did not immediately respond to a request for comment.

Trevor Cadigan (Courtesy of WFAA/AP)

Cadigan’s family is also suing the pilot, identified in court records as Richard Vance, for “failing to take reasonable steps to extricate the passengers.” The Washington Post was unable to reach Vance, who authorities said had been hospitalized. His brother, Anthony Vance, told CNN that “he did his job and got out alive.”

“Just let him be,” Anthony Vance said.

The National Transportation Safety Board, which is investigating the cause of the crash, said the pilot declared “mayday” and reported an engine failure moments before the helicopter hit the water.

The lawsuit alleges that Vance “inadvertently or otherwise activated” the emergency fuel shut-off button and “failed to properly activate” the helicopter’s skid floats.

It remains unclear whether the helicopter experienced mechanical problems after takeoff, or if the harnesses and the floating devices were working properly.

The crash also killed  Brian McDaniel, 26, Cadigan’s friend who was visiting him from Dallas; Tristan Hill, 29, and  Daniel Thompson, 34, both of New York; and  Carla Vallejos Blanco, 29, an Argentine vacationing in New York.

Freeing oneself after a helicopter crashes in  water involves several steps, including unplugging communication cords or headsets and undoing the seat belt and harness, said Barbara Kaiser, a Florida-based aviation expert. Removing the harness alone takes time and requires someone to use a knife to cut it.

“Each step takes time and in an emergency, especially underwater, seconds count,” Kaiser said. “Nobody has time to learn how to cut a heavy harness strap underwater while holding their breath.

“To cut the seat belt or cut the harness, they’re going to struggle a little bit because they’ve never done it before,” Kaiser said of the passengers. “The whole process takes special training. These people, the passengers, they never had a chance because they’d never taken any training.”

The helicopter was one of three that took off from a heliport in Kearny, N.J., just before 7 p.m. Sunday, said Eric Adams, an aviation writer who was a passenger in a different helicopter. He said all the passengers had attended a short safety briefing, which included a 10-minute video.

“There’s no way those people could’ve gotten out of the helicopter,” Adams said. “Not with the training they had. Not even me, and this is my third time.”

Robb, the attorney, said Cadigan’s parents want the defendants “to cease and desist this terribly unsafe open-door flight operation.” The lawsuit does not specify the amount of damages the family is seeking.

“It is their strongest desire that this should never happen again,” Robb said.

A number of plane and helicopter crashes over New York City’s East and Hudson rivers have claimed lives in the past several years. At least three incidents over the past decade, including the crash Sunday, involved Liberty Helicopters.

Samantha Schmidt contributed to this article.

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