NEW YORK — A JetBlue flight attendant whose rant at a passenger and memorable exit from the plane via emergency chute made him a kind of working-class hero pleaded guilty Tuesday to criminal mischief and agreed to undergo mental health and alcohol abuse counseling.

“”While the public interest was surprising, at the end of the day, I am a grown-up and must take responsibility,”” Steven Slater, 38, of Belle Harbor, said outside court in Kew Gardens, Queens.

Slater pleaded guilty to two counts of criminal mischief, one of them a felony and the other a misdemeanor. A prison sentence of 1 to 3 years will be suspended while he completes a 12-month program in Queens Mental Health Court.

Slater answered “”Yes, your honor”” when state Supreme Court Justice Marcia P. Hirsh asked if he understood his plea agreement.

On Aug. 9, Slater swore at a passenger on a JetBlue flight that had landed at Kennedy Airport before sliding down the emergency exit chute that he deployed.

After his dramatic exit, police arrested Slater at his Queens home.

Overnight, he became a symbol for stressed-out workers everywhere, with his lawyer saying a passenger’s “”lack of civility”” prompted Slater’s behavior.

He had been charged with criminal mischief, reckless endangerment and criminal trespass — charges that carried the possibility of at least 7 years in prison — and was freed on $2,500 bail.

Slater, who initially was suspended from his JetBlue job and then resigned in September, has to pay JetBlue $10,000 for repair of the emergency chute and other expenses.

District Attorney Richard Brown said, “”As we interviewed various passengers, it became increasingly clear to me and most of my staff that the defendant’s actions were at least in part due to mental health and alcohol issues.””

While Brown acknowledged that Slater seemed to morph into a “”folk hero,”” the district attorney said he was anything but. The slide that Slater activated was under pressure of 3,000 pounds per square inch, and could have injured or killed passengers or workers on the tarmac, he said.

If Slater completes the treatment program, he will be allowed to withdraw his guilty plea to the felony charge after a year and will be sentenced to one-year’s probation on a misdemeanor charge of criminal mischief, the district attorney said.