Extract from : Rainbow Six

The usual sensations. The aircraft tilted, more to the right than the left, as it crossed over the ocean at Sea Isle City in New Jersey for the three-thousand-mile flight to the next landfall, somewhere on the Irish coast, which they'd reach in about five and a half hours, John thought. He had to sleep for some of that time. At least the captain didn't bother them with the usual tour-director crap-we are now at forty thousand feet, that's almost eight miles to fall if the wings come off and . . . They started serving dinner. They'd be doing the same aft in tourist class, with the drink and dinner carts blocking the aisles.
It started on the left side of the aircraft. The man was dressed properly, wearing a jacket - that was what got John's attention. Most people took them off as soon as they sat down but ... it was a Browning automatic, with a flat-black finish that said "military" to Clark, and, less than a second later, to Alistair Stanley. A moment later, two more men appeared on the right side, walking right next to Clark's seat ... [Sandy] turned and looked, but before she could do or say anything, he grabbed her hand. That was enough to keep her quiet, but not quite enough to keep the lady across the aisle from screaming-well, almost screaming. The woman with her covered her mouth with a hand and stifled most of it. The Stewardess looked at the two men in front of her in total disbelief. This hadn't happened in years. How could it be happening now?
Clark was asking much the same question, followed by another: Why the hell had he packed his sidearm in his carry-on and stowed it in the overhead? What was the point of having a gun on an airplane, you idiot, if you couldn't get to it? What a dumbass rookie mistake! He only had to look to his left to see the same expression on Alistair's face. Two of the most experienced pros in the business, their guns less than four feet away, but they might as well be in the luggage stored below. . . .
"John . . ."

"Just relax, Sandy," her husband replied quietly.

More easily said than done, as he well knew.
John sat back, keeping his head still, but turned away from the window and toward the cabin. His eyes moved free. Three of them. One, probably the leader, was taking a stew forward, where she unlocked the door to the flight deck. John watched the two of them go through and close the door behind them. Okay, now Captain William Garnet would find out what was going on. Hopefully he would be a pro, and he'd be trained to say yes, sir-no, sir-three-bags-full, sir to anybody who came forward with a gun. At best he'd be Air Force- or Navy-trained, and therefore he'd know better than to do anything stupid, like trying to be a goddamned hero. His mission would be to get the airplane on the ground, somewhere, anywhere, because it was a hell of a lot harder to kill three hundred people in an airplane when it was sitting still on the ramp with the wheels chocked.
Three of them, one forward in the flight deck. He'd stay there to keep an eye on the drivers and to use the radio to tell whomever he wanted to talk to what his demands were. Two more in first class, standing there, forward, where they could see down both aisles of the aircraft.
"Ladies and gentlemen, this is the captain speaking. I've got the seat-belt sign on. There's a little chop in the air. Please stay in your seats for the time being. I'll be back to you in a few minutes. Thank you."
Good, John thought, catching Alistair's eye. The captain sounded cool, and the bad guys weren't acting crazy-yet. The people in back probably didn't know anything was wrong - yet. Also good. People might panic . . . well, no, not necessarily, but so much the better for everyone if nobody knew there was anything to panic about. Three of them. Only three? Might there be a backup guy, disguised as a passenger? That was the one who controlled the bomb, if there was a bomb, and a bomb was the worst thing there could be. A pistol bullet might punch a hole in the skin of the aircraft, forcing a rapid descent, and that would fill some barf bags and cause some soiled underwear, but nobody died from that. A bomb would kill everyone aboard, probably . . . better than even money, Clark judged, and he hadn't gotten old by taking that sort of chance when he didn't have to. Maybe just let the airplane go to wherever the hell these three wanted to go, and let negotiations start, by which time people would know that there were another three very special people inside. Word would be going out now. The bad guys would have gotten onto the company radio frequency and passed along the bad news of the day, and the Director of Security for United - Clark knew him, Pete Fleming, former Deputy Assistant Director of the FBI - would call his former agency and get that ball rolling, to include notification of CIA and State, the FBI Hostage Rescue Team in Quantico, and Little Willie Byron's Delta Force down at Fort Bragg. Pete would also pass along the passenger list, with three of them circled in red, and that would get Willie a little nervous, plus making the troops at Langley and Foggy Bottom wonder about a security leak - John dismissed that. This was a random event that would just make people spin wheels in the Operations Room in Langley's Old Headquarters Building. Probably.