Renegade flight attendant Steven Slater might want his job back at JetBlue Airlines, but the company's top officials are already questioning what set off his now-legendary meltdown on a New York-bound flight this week.

"There's much more to this story that we don't know," wrote JetBlue COO Rob Maruster in an internal memo obtained by the Wall Street Journal.

Slater's attorney said the 38-year-old has flying "in his blood," but JetBlue is trying to determine what set that blood to boiling Monday, when Slater spewed a string of curses over the public address system and made a daring -- if short-lived -- getaway down the plane's emergency chute, sliding onto the tarmac with two beers in hand. He was later arrested at home in Queens, N.Y.

"Was there an altercation on the flight that precipitated or motivated Mr. Slater's action? It's unclear," Maruster wrote. "No one has stepped forward to tell their side of the story, and multiple Customers from different areas of the cabin have given interviews that tell a different story. It's difficult to know with certainty what really happened."

Maruster made clear in his memo, sent to staff and JetBlue's board of directors, that no trigger could possibly excuse Slater's actions, which Maruster described as "unacceptable" -- and deadly serious.

"Slides deploy extremely quickly, with enough force to kill a person," he wrote. "Slides can be as dangerous as a gun, and that's the reason we have intensive initial and recurrent training. It is an insult to all aviation professionals to have this particular element of the story treated without the seriousness it deserves."

While Slater's actions have prompted support from people who have fantasized about making a similar exit from an unpleasant job, some passengers have come forward to criticize him as brusque and cranky throughout the 90-minute flight from Pittsburgh. One passenger portrayed Slater as the instigator, saying he cursed without provocation at a woman who had asked about her bag.

Attorney Howard Turman portrayed his client as hardworking, loyal and surprised by his own overnight fame.

Slater "wants to thank the world for its understanding," Turman said, referring to the Internet and media response to his client's public unraveling.

"This is a man who only cares about his industry," the attorney said, adding that Slater especially cares about JetBlue, which "has been a fair and understanding airline."

Slater would not talk about his actions Thursday. He smiled silently for most of the 10-minute news conference, then offered a brief thanks to the public, saying, "It's been amazing, the support and love ... everything that's been brought to me."

Turman denied Slater was belligerent and said the entire affair can be blamed on a "lack of civility on the part of one passenger."

Passenger Lauren Dominijanni, 25, of Pittsburgh, said that during the trip, when she asked Slater for a wipe to clean up coffee that had been spilled on her seat, he rolled his eyes, blurted an exasperated "What?" and gestured to the gash on his head. He then told her he needed to take care of himself first, she said.

Later, after the plane landed, passengers said they heard Slater and other crew members repeatedly instruct a passenger to remain seated until the jet reached the gate. The traveler apparently didn't listen. Slater ultimately had to leave his seat to get the person to sit down.

Authorities said Slater had grabbed at least one beer from the jet's galley before jumping out. Turman denied that his client had been drinking during the flight.

Asked about Slater's references on a social networking site about his battle with addiction, Turman would not comment.

Slater faces charges of criminal mischief, reckless endangerment and trespassing.

Click here for more on this story from the Wall Street Journal.

The Associated Press contributed to this report.