Kinman Chan, a 30-year-old artist from San Francisco with a prescription for medical marijuana, picked the wrong flight to freak out on.

He was arrested on Sunday when his US Airways plane from Philadelphia to San Francisco had to be diverted to Pittsburgh after he became disruptive and attempted to hit one of the flight attendants.

Unfortunately for him, the woman he tried to strike, Lorin Gorman, 51, of Chula Vista, Calif., is a fourth-degree black belt in tae kwon do.

She dodged him, locked his arm behind his back and then jumped in the seat behind him and put him in a choke hold.

"She took him down all right," said Ms. Gorman's mother, Betty Gorman. "He was dealing with the wrong flight attendant."

According to a criminal complaint filed in federal court, Mr. Chan was acting strangely from the beginning of the flight.

At first, he was waving, smiling and making odd gestures to Ms. Gorman. Then, the complaint went on, shortly after takeoff, he went to the restroom on the plane and began to scream.

When another crew member knocked on the door, Mr. Chan came out with his shirt untucked and his pants down. All of the restroom compartments were open. The crew member attempted to get him back to his seat, but Mr. Chan refused.

He then put his hands together as if he were praying, at which point the crew member removed Mr. Chan and escorted him to his seat, the complaint said.

Mr. Chan became aggressive and attempted to hit Ms. Gorman.

That's when her years of training paid off, Betty Gorman said.

Her daughter manhandled Mr. Chan to restrain him, pinning his arm behind his back and eventually using a choke hold, the complaint said.

"If you think that's impressive, you should see her break four or five boards spinning [and] blindfolded," Betty Gorman said.

Mr. Chan, who was traveling back from a conference in the Dominican Republic, was put into handcuffs, and the flight landed in Pittsburgh. He is charged with interfering with flight crew members.

Mr. Chan admitted causing the disturbance and told federal agents he had eaten marijuana cookies while waiting for his connecting flight in Philadelphia.

He told them that he had a medical marijuana card and took double his normal dose.

A preliminary hearing on the matter was scheduled for Wednesday, but was continued until Friday.

Mr. Chan is being held in the Allegheny County Jail on a separate state count of disorderly conduct.

He has been unable to post the $200 required to make bond.

According to pictures posted on his blog, Kincept Co., Mr. Chan is a concept artist in the film industry.

Craig Shoji, who went to school with Mr. Chan, and has been his friend for six years, said the alleged behavior on the plane is completely incongruous with the man he knows.

He said he didn't know his friend to use drugs, and that he "never acted like a pothead." Instead, he described him as responsible and entrepreneurial.

"As smart as he is, he does have a bit of child-like naivete that might get him into trouble," Mr. Shoji said. "He's a gentle guy that wouldn't hurt a fly, and his personality is very endearing."

Lorin Gorman, who was on a flight and couldn't be reached, has been practicing tae kwon do for many years and just recently earned her fourth-degree black belt, her mother said.

The woman originally wanted to go into the Navy's flight program, but she missed the age cutoff while in college.

Instead of becoming a pilot, Lorin Gorman, who is friends with Capt. Chesley B. Sullenberger III -- the US Airways pilot who last year landed on the Hudson River -- chose to be a flight attendant.

"She had to get on a plane one way or the other," her mom said.

Looking for more from the Post-Gazette? Join PG+, our members-only web site. You'll get exclusive sports content, opinion, financial information, discounts from retailers and restaurants, and more. Our introduction to PG+ gives you all the details.