John Cutter: Now I'm sick of your shit.
Charles Rane: You need the passengers, I need the plane. Put me back on board and the passengers will be released.
John Cutter: Yeah right. I'm supposed to trust you?
Charles Rane: Trust your instincts.
John Cutter: My instincts are to wax your ass all over this floor.
Charles Rane: Those are your emotions acting without the benefit of intellect.
John Cutter: I know mother fuckers who say they've seen Elvis at the goddamn mall! You believe that shit too?
Charles Rane: You wouldn't take advantage of a helpless man.
John Cutter: Never stopped you.
Charles Rane: It's the American way, isn't it, brother?
John Cutter: Charlie, ever played roulette?
Charles Rane: On occasion.
John Cutter: Well, let me give you a word of advice. Always bet on black.
John Cutter: Look chief, I thought all of you ham hogging, country biscuit eating boys knew how to drive? Was it a bunch of bullshit or what?
Chief Biggs: I haven't had a challenge like that since I was in high school.
John Cutter: Chief, I didn't know you went to high school?
Sly Delvecchio: You know, that's what I admire about you! Even though you are being hit on by absolutely beautiful woman, you are determined to maintaining your vow of chastity. You know, you'd make a hell of a republican.
Sabrina Ritchie: And how would you like your sirloin, sir?
Charles Rane: Bloody.
First Officer: We were told to head back.
Sabrina Ritchie: By whom?
John Cutter: By me.
John Cutter: Plan not working out the way you wanted? Asshole?
Charles Rane: Don't flatter yourself Cutter. You prevented nothing. Although it seems I may have underestimated you.
Answer: It's been a while since I've watched this movie, but he obviously knows the plane is hijacked. It's a pretty safe assumption that the agents are dead as they're escorting a dangerous, high profile prisoner. Pretty easy to connect the dots. Alternatively, they could've failed to check in, and he assumed the worst.