Mike Tyson seemed to lose his cool on a plane on Wednesday night

The incident all went down at around 10:30 PM PT as Tyson was slated to fly out of San Francisco International Airport to Florida. A witness on the plane says as he and his friend were boarding Tyson's flight ... the boxing legend was initially cool with them and the other passengers. Eventually, Tyson had enough of the guy behind him talking in his ear ... and told him to chill. When the guy didn't, that's when the witness says Tyson started to throw several punches at the man's face. The man who was punched received medical attention and then went to the police over the incident.