Tarnished. That's what's becoming of Justin Bieber's once pristine reputation. The 17-year-old singer has engaged in a rash of bad behaviors lately, which FOX News detailed, begging the question whether or not the formerly squeaky clean Biebs is turning into a celeb brat. Is The Biebs a big time terror or just a boy being a boy?

We reported on how The Biebs' 'CSI' co-star Marg Helgenberger referred to him as a brat while his also clean cut girlfriend Selena Gomez is said to be a bit unhappy with The Biebs' boys and bros, like Chris Brown. Bieber was also all braggadocio in his delivery on Brown's mixtape track -- which surprised some of us.

FOX411's Pop Tarts reports that on a recent flight to Asia, from Los Angeles, The Biebs got his brat on too.

Eyewitnesses -- and you all know how reliable those can be -- claimed The Biebs was not cooperating with flight staff when they asked him to take his seat in preparation for takeoff.

"He then gave the staff a really hard time the whole flight, nobody could believe it,” said the source. “And then at the end, the Captain introduced himself to Justin and kindly asked for an autograph, and he rudely refused." The Biebs refused an autograph? That doesn't sound like him. Reps for American Airlines and the 'Baby' singer did not respond to requests for comment.

Also, you may remember that David Koch, the host of Australian breakfast TV show 'Sunrise,' said that Bieber had a bad attitude and performed poorly during his appearance. Koch also said that the singer scolded the floor manager who was attempting to direct him on where to perform, screaming "Don't ever f---ing touch me again." Oi.

"I thought, 'Maybe someone needs to drag you aside and give you a bit of a slap,'" Koch continued.

Bieber later defended himself against the allegations, tweeting: "hearing adults spread lies and rumors is part of the job I guess. But all I have to say is … Kill em with kindness. So everyone keeps smiling.”

FOX also reports that the Biebs snubbed a fan who waited for him at a Philippines airport but he tweeted that he was sick and that's why he did not approach the fan.

Oh Biebs, your PR team needs to go into damage control mode, stat. You don't want this to get any worse.