At the hearing, Judge Peter Hobbs said that Jetstar contractor Patrick Joseph Ulberg had acted in self defence after Mr Stables threw a portable radio at Mr Ulberg.
Mr Stables had been told he had missed his flight and is alleged to have made a racist slur before being punched in the face.
Last month, Mr Ulberg had a smile on his face as he left court with his lawyer.
"It's a big lesson for all people. I have to calm down myself."
Mr Stables told the Herald at the time that he never punched Mr Ulberg, threw a radio or made any kind of racist comments.
As he handed down his verdict last month, Judge Hobbs said Mr Stables had told a court hearing that he was upset when he couldn't get on his flight.
Mr Stables told the court that he had said to Mr Ulberg and his colleague: "You guys are a loser airline. You're a loser from a loser airline."
Mr Stables had said Mr Ulberg threatened him before attacking and he received a "constant attack to the head" and was punched again while on the ground.
Judge Hobbs said Mr Ulberg's evidence was that he was called a "black mother f*****" by Mr Stables who leaned over the waist-high counter and punched him in the chest.
Judge Hobbs said there were obvious contradictions in the accounts.
CCTV footage showed Mr Stables sweeping bag labels off the counter and throwing a radio at Mr Ulberg.
"That in itself is an assault," Judge Hobbs said.
He said Mr Stables was more than a disgruntled customer. "He was aggressive and abusive."
Judge Hobbs said an independent witness, Manish Patel, standing two metres away saw Mr Stables "mouthing off" before throwing something.
Mr Patel also recalled Stables calling Mr Ulberg a "black mother f*****".
He did not see who was throwing punches before Mr Stables slipped over then got back up.
"At that point, Mr Patel said he saw the defendant connect one or two punches to the face area."
Judge Hobbs said he could not be satisfied beyond reasonable doubt that Mr Ulberg was not acting in self-defence.
Mr Stables said he was stunned by Judge Hobbs' verdict. "I'm the one who got smashed up. I didn't punch anyone... I put up a pathetic fight."
He repeatedly denied making racist comments. "I'm in the public eye. I've never done anything like that."