JACKSONVILLE, Fla. – An unruly passenger aboard a Jacksonville-bound flight pleaded guilty to attacking a flight attendant.
Joseph Sharkey, 36, faces a maximum penalty of 20 years in federal prison. He must remain in custody pending a sentencing hearing, which has not yet been scheduled.
Sharkey was arrested Jan. 31 by the FBI when a JetBlue flight from Washington's Regan National Airport landed at Jacksonville International Airport. He was charged with assault or intimidation of a flight crew.
"It would be well within the judge's discretion to give this individual some time in prison," said Ed Booth, a pilot and attorney, who is not involved in the case. "The chance of a passenger interfering with the pilots is very remote. However, the flight attendants are at tremendous risk."
The incident happened during Flight 715, which landed safely at JAX around 4 p.m. Sharkey was removed from the flight by Jacksonville Aviation Authority Police.
His arrest was captured on cellphone video by another passenger.
WATCH: Passenger arrested on JetBlue flight
According to court documents, during the final 20 minutes of the flight, Sharkey attempted to place another passenger in a headlock, and a flight attendant assisted that passenger and ordered Sharkey to take a seat.
Sharkey at first complied, but then kneed the flight attendant in the groin and said he was going to leave the airplane through an exit door. He also claimed to be a federal air marshal.
Passengers volunteered to help flight attendants subdue Sharkey, who was placed in zip ties for the remainder of the flight.
Booth said he wouldn't be surprised if Sharkey is given probation, required to take anger management courses and banned from flying.
According to the FBI, Sharkey had four alcoholic drinks on the flight, which likely contributed to the altercation.
Booth said staff needs to be careful.
"The airline has some responsibility to cut people off," Booth said. "It is a controlled environment, and they have the drink cart. And if were I representing this individual, I may make the argument that the airline bears some of the responsibility for allowing him to get into that situation."
The passenger who was attacked on the flight, Kyriakos “Dom” Doukas, sent a letter to JetBlue officials urging them to change their policies and limit the number of alcoholic drinks passengers can have.
The FBI said neither Sharkey nor anyone else on the plane was injured.
After the flight landed and Sharkey was removed by airport police, he was taken to an interview room by FBI agents. Officials said that while there, Sharkey howled like a dog for about 20 minutes, attempted to leave and then urinated on the floor.
JetBlue declined to comment on Sharkey's guilty plea.