A plane sits outside the American Airlines facility at LaGuardia Airport in New York in March. (John Minchillo/AP)

Editor’s note: The Post has learned that this article contained several passages that were largely duplicated, some without attribution, from a story published by the New York Times. Post policy forbids the unattributed use of material from other sources.

About three hours into her April 2016 flight from Honolulu to Dallas-Fort Worth, Brittany Oswell, a 25-year-old nurse, fell ill.

She became dizzy and disoriented, slurring her speech. When she briefly fainted, a flight attendant found a doctor on board who examined her and believed she was having a panic attack.

But the symptoms that followed indicated Oswell was suffering from something more severe, according to a wrongful-death lawsuit filed against American Airlines in federal court in South Carolina last week. About an hour later, when the flight was over New Mexico, Oswell’s husband accompanied her to the lavatory, where she collapsed — vomiting on herself and on the flight attendants who came to help her. The doctor returned, and this time relayed a different command: Divert the plane.

But an emergency landing was never attempted, according to the lawsuit. Oswell died of a pulmonary embolism three days later in a Texas hospital.

The lawsuit, filed by Oswell’s parents, Chris and Tina Starks, as well as her widowed husband, Cory Oswell, details the frenzied moments on the plane, during which the doctor — who is not named in the lawsuit — tried to use the plane’s medical equipment to treat her and tried to get the pilot to land. The lawsuit alleges that, when the doctor tried to take Oswell’s blood pressure, one of the plane’s cuffs didn’t work, and that the other was faulty.

About 30 minutes had passed from the time the doctor had asked for the emergency landing.

The pilot summoned the doctor, who explained that Oswell needed immediate assistance and recommended the plane be diverted. But the pilot flew on for Dallas-Fort Worth International Airport, which was 90 minutes away, according to the lawsuit.

Oswell’s breathing and pulse eventually stopped. The doctor and flight attendants administered CPR after using an onboard defibrillator, which the family alleges failed to work. Oswell never regained consciousness and was taken off life support three days later.

“We were deeply saddened by this event and our thoughts and prayers continue to go out to Mrs. Oswell’s loved ones,” an American Airlines spokesman said in a statement. “We take the safety of our passengers very seriously and we are looking into the details of the complaint.”

Oswell’s family, in the lawsuit, accuses American Airlines of gross negligence, alleging the airline contributed to Oswell’s death by failing to divert the plane and by “failing to provide proper working equipment and medical supplies.”

The family is seeking damages in an unspecified amount for “severe emotional distress, anxiety, grief and sorrow.”

“Cory has suffered and will continue to suffer great pain, humiliation and mental anguish and loss of enjoyment of his marital life, for which the defendant is liable to him,” the lawsuit states.

Oswell’s family could not be immediately reached by The Washington Post for comment. In an interview with the New York Times on Friday, Oswell’s parents said they are still grappling with her death two years later.

“A decision was made not based on the human life that was on board or based on safety,” Tina Starks said. “Frustration doesn’t really describe how disappointed and heartbroken and just immensely discombobulating it has been.”

Brittany and Cory Oswell were on their way back to their home state of South Carolina to live with her parents in Columbia after spending a year living in Hawaii, the Times reported. Cory Oswell, who was in the Army, had been medically discharged.

Brittany Oswell told her mother she’d call her when the couple landed in Dallas-Fort Worth. But the call came from her husband instead.

“I could detect in his voice that it was very different,” Starks told the Times. “He said, ‘Ms. Starks, something happened.’ ”

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