Airframe (Page 27)

"I tried," he said. "With no success. I hesitate to say it is useless, but – what about the QAR?"

"No QAR, Felix."

"Ah." Wallerstein sighed.

They came to the command console, a series of video screens and keyboards to one side of the building. Here the instructors sat while they monitored the pilots being trained in the simulator. Two of the simulators were being used as they watched.

Casey said, "Felix, we’re concerned the slats extended in cruise flight. Or possibly the thrust reversers."

"So?" he said. "Why should that matter?"

"We’ve had problems with slats before…"

"Yes, but that is long since fixed, Casey. And slats cannot explain such a terrible accident Where people are killed? No, no. Not from slats, Casey."

"You’re sure"

"Absolutely. I will show you." He turned to one of the instructors at the console. "Who’s flying the N-22 now?"

"Ingram. First officer from Northwest"

"Any good?"

"Average. He’s got about thirty hours."

On the closed-circuit video screen, Casey saw a man in his mid thirties, sitting in the pilot’s seat of the simulator.

"And where is he now?" Felix said.

"Uh, let’s see," the instructor said, consulting his panels. "He’s over the mid-Atlantic, FL three-thirty, point eight Mach."

"Good," Felix said. "So he’s at thirty-three thousand feet, eight-tenths the speed of sound. He’s been there awhile, and everything seems to be fine. He’s relaxed, maybe a little lazy."

Chapter 7

"Yes, sir."

"Good. Deploy Mr. Ingram’s slats."

The instructor reached over and pushed a button.

Felix turned to Casey. "Watch carefully, please."

On the video screen, the pilot remained casual, unconcerned. But a few seconds later, he leaned forward, suddenly alert, frowning at his controls.

Felix pointed to the instructor’s console, and the array of screens. "Here you can see what he is seeing. On his Flight Management display, the slats indicator is flashing. And he’s noticed it. Meanwhile, you see the plane gives a slight nose up…"

The hydraulics whirred, and the big cone of the simulator tilted upward a few degrees.

"Mr. Ingram now checks his slats lever, as he should. He finds it is up and locked, which is puzzling, since it means he has an uncommanded slats deploy …"

The simulator remained tilted up.

"So Mr. Ingram is thinking it over. He has plenty of time to decide what to do. The aircraft is quite stable on autopilot Let’s see what he decides. Ah. He decides to play with his controls. He pulls the slats lever down, then up… He’s trying to clear the warning. But that doesn’t change anything. So. He now realizes he has a system problem on his aircraft. But he remains calm. He’s still thinking … What will he do? … He changes the autopilot params … he descends to a lower altitude, and reduces his airspeed… absolutely correct… He is still in the nose-up attitude, but now at more favorable conditions of altitude and speed. He decides to try the slats lever again…"

The instructor said, "Should I let him off the hook?’

"Why not?" Felix said "I believe we have made the point."

The instructor punched a button. The simulator tilted back to level.

"And so," Felix said, "Mr. Ingram is restored to normal flight. He makes a note of his problem for the maintenance crews, and he continues on his way to London."

"But he stayed in the autopilot" Casey said. "What if he went out of it?"

"Why should he do that? He’s in cruise flight; the autopilot has been operating the plane for at least half an hour."

"But suppose he did."

Felix shrugged, turned to the instructor. "Fail his autopilot."

"Yes, sir."

An audible alarm sounded. On the video screen, they saw the pilot look at the controls and take the stick in his hands. The audible alarm ended; the cockpit became silent. The pilot continued to hold the stick.

"Is he flying the plane now?" Felix asked.

"Yes, sir," the instructor said. "He’s at FL two-ninety, point seven-one Mach, with autopilot disabled."

"Okay," Felix said. "Deploy his slats."

The instructor pushed a button.

On the systems monitor in the training console, the slats warning flashed, first amber, then white. Casey looked at the adjacent video screen and saw the pilot leaning forward. He had noticed the warning in the cockpit.

"Now," Felix said. "Once again we see the aircraft nose-up, but this time Mr. Ingram must control it himself … So he brings the stick back … very slightly, very delicately … Good… and now he is stable."

He turned to Casey. "You see?" He shrugged. "It is very puzzling. Whatever happened to that Transpacific flight, it cannot be the slats. And not thrusters either. In either case, the autopilot will compensate and maintain control. I tell you, Casey, what happened to that aircraft is a mystery."

Back in the sunlight, Felix walked over to his Jeep, with a surfboard on top. "I have a new Henley board," he said. "Like to see it?"

"Felix," she said. "Marder is starting to scream."

"So? Let him. He enjoys it."

"What do you think happened to 545?"

"Well. Let us be frank. Flight characteristics of an N-22 are such that if slats deploy at cruise speed, and the captain goes out of the autopilot the aircraft is rather sensitive. You remember, Casey. You did the study on it, three years ago. Right after we made the final fix on the slats."