Kay Liang nodded. "It is a lever in the center pillar, between the chairs."

That was correct, Casey thought.

"Did you notice the lever at that time? While you were in the cockpit?"

"Yes. It was in the up and locked position."

Again, Casey noted the terminology. A pilot would say, Up and locked. Would a flight attendant?

"Did he say anything else?"

"He was concerned about the autopilot. He said the autopilot kept trying to cut in, to take over the plane. He said 'I had to fight the autopilot for control.'"

"I see. And what was Captain Chang's manner at this time?"

"He was calm, as always. He is a very good captain."

The girl's eyes flickered nervously. She twisted her hands in her lap. Casey decided to wait for a moment. It was an old interrogator's trick: let the subject break the silence.

"Captain Chang comes from a distinguished family of pilots," Kay Liang said, swallowing. "His father was a pilot during the war, and his son is a pilot as well."

"I see ..."

The flight attendant lapsed into silence again. There was a pause. She looked down at her hands, then back up. "So. Is there anything else I can tell you?"

Outside the cubicle, Richman said, "Isn't this the thing you said couldn't happen? Uncommanded slats deployment?"

"I didn't say it couldn't happen. I said I didn't believe it was possible on this aircraft. And if it did, it raises more questions than it answers."

"And what about the autopilot - "

'Too early to tell," she said, and went into the next cubicle.

"It must have been around six o'clock," Emily Jansen said, shaking her head. She was a slender woman of thirty, with a purple bruise on her cheek. An infant slept on her lap. Her husband lay in the bed behind her; a metal brace ran from his shoulders to his chin. She said his jaw was broken.

"I had just fed the baby. I was talking to my husband. And then I heard a sound."

"What sort of a sound?"

"A rumbling or a grinding sound. I thought it came from the wing."

Not good, Casey thought.

"So I looked out the window. At the wing."

"Did you see anything unusual?"

"No. It all looked normal. I thought the sound might be coming from the engine, but the engine looked normal, too."

"Where was the sun that morning?"

"On my side. Shining in on my side."

"So was there sunlight on the wing?"

"Yes."

"Reflecting back at you?"

Emily Jansen shook her head. "I don't really remember."

"Was the seat-belt sign on?'

"No. Never."

"Did the captain make an announcement?"

"No."

"Going back to this sound - you described it as a rumble?"

"Something like that. I don't know if I heard it, or felt it. It was almost like a vibration."

Like a vibration.

"How long did this vibration last?"

"Several seconds."

"Five seconds?"

"Longer. I would say ten or twelve seconds."

A classic description of a slats deployment in flight, Casey thought.

"Okay," she said. "And then?"

"The plane started going down." Jansen gestured with the flat of her hand. "Like that."

*   *   *

Casey continued to make notes, but she no longer really listened. She was trying to put together the sequence of events, trying to decide how the engineers should proceed. There was no question that both witnesses were telling a story consistent with slats deployment. First, rumbling for twelve seconds -  exactly the time it took the slats to extend. Then a slight nose up, which would occur next. And then porpoising, as the crew tried to stabilize the aircraft.

What a mess, she thought.

Emily Jansen was saying, "Since the cockpit door was open, I could hear all the alarms. There were warning sounds - and voices in English that sounded recorded."

"Do you remember what they said?"

"It sounded like 'Fall... fall.' Something like that."

It was the stall alarm, Casey thought. And the audio reminder was saying, "Stall, stall."

Damn.

She stayed with Emily Jansen a few minutes more and then went back outside.

In the corridor, Richman said, "Does that rumbling sound mean the slats deployed?"

"It might," she said. She was tense, edgy. She wanted to get back to the aircraft, and talk to the engineers.

From one of the curtained cubicles farther down .the corridor, she saw a stocky gray-haired figure emerge. She was surprised to see it was Mike Lee. She felt a burst of irritation: What the hell was the carrier rep doing talking to passengers? It was very inappropriate. Lee had no business being here.

She remembered what Kay Liang had said: A Chinese man was just here.

Lee came up toward them, shaking his head.

"Mike," she said. "I'm surprised to see you here."

"Why? You should give me a medal," he said "A couple of the passengers were considering lawsuits. I talked them out of it."

"But Mike," she said. "You talked to crew members before we did. That's not right."

"What do you think, I fed them a story? Hell, they gave me the story. And there's not much doubt about what happened." Lee stared at her. "I'm sorry, Casey, but Flight 545 had an uncommanded slats deploy, and that means you've still got problems on the N-22."

Walking back to the van, Richman said, "What did he mean, you've still got problems?"

Casey sighed. No point in holding back now. She said, "We've had some incidents of slats deployment on the N-22."

"Wait a minute," Richman said. "You mean this has happened before?"

"Not like this," she said. "We've never had serious injuries. But yes, we've had problems with slats."

EN ROUTE

1:05 P.M.

"The first episode occurred four years ago, on a flight to San Juan," Casey said, as they drove back. "Slats extended in mid-flight. At first, we thought it was an anomaly, but then there were two additional incidents within a couple of months. When we investigated, we found that in every case the slats had deployed during a period of flight deck activity: right after a crew change, or when they punched in coordinates for the next leg of the flight, or something like that. We finally realized the slats lever was getting knocked loose by the crews, banged by clipboards, caught on uniform sleeves - "

"You're kidding," Richman said.

"No," she said. "We'd built a locking slot for the lever, like 'park' on an automobile transmission. But despite the slot, the lever was still being accidentally dislodged."

Richman was staring at her with the skeptical expression of a prosecuting attorney. "So the N-22 does have problems."

"It was a new aircraft," she said, "and all aircraft have problems when they're first introduced. You can't build a machine with a million parts and not have snags. We do everything we can to avoid them. First we design, then we test the design. Then we build, then we flight test. But there are always going to be problems. The question is how to resolve them."

"How do you resolve them?"

"Whenever we discover a problem, we send the operators a heads-up, called a Service Bulletin, which describes our recommended fix. But we don't have the authority to mandate compliance. Some carriers implement, some don't If the problem persists, the FAA gets into the act and issues an Airworthiness Directive to the carriers, requiring them to fix the planes in service within a specified time. But there are always ADs, for every model aircraft. We're proud of the fact that Norton has fewer than anyone else."

"So you say."

"Go look it up. They're all on file at Oak City."

"At what?"

"Every AD that's ever been issued is on file at the FAA's Technical Center in Oklahoma City."

"So you had one of these ADs on the N-22? Is that what you're telling me?"

"We issued a Service Bulletin recommending the carriers install a hinged metal cover that sits over the lever. That meant the captain had to flip up the cover before he could deploy the slats, but it solved the problem. As usual, some carriers made the fix, others didn't. So the FAA issued an AD making it mandatory. That was four years ago. There's been only one incident since then, but that involved an Indonesian carrier who didn't install the cover. In this country, the FAA requires carriers to comply, but abroad ..." She shrugged. "The carriers do what they want."

"That's it? That's the whole history?"

"That's the whole history. The IRT investigated, the metal covers were installed on the fleet, and there haven't been any more slats problems on the N-22."

"Until now," Richman said.

"That's right. Until now."

LAX MAINTENANCE HANGAR

1:22 PM.

"A what?" Kenny Burne said, shouting from the cockpit of Transpacific 545. "They said it was what!"

"Uncommanded slats deployment," Richman said.

"Aw, blow me," Burne said. He started climbing out of the seat. "What a crock of shit. Hey! Clarence, come in here. See that seat? That's the first officer's seat. Sit down there."

Richman was hesitant.

"Come on, Clarence, get in the damn seat."

Awkwardly, Richman squeezed between the other men in the cockpit, and got into the first officer's chair on the right.

"Okay," Burne said. "You comfy in there, Clarence? You're not a pilot, by any chance?"

"No," Richman said.

"Okay, good. So, here you are, all set to fly the plane. Now, you see straight ahead" - he pointed to the control panel directly in front of Richman, which consisted of three video screens, each four inches square - "you got your three color CRTs showing your primary flight display, navigation display, and on the left, systems display. All those little semicircles represent a different system. All green, meaning everything's fine. Now, on the roof above your head, that's your overhead instrument panel. All the lights are out, which means everything is fine. It's dark unless there's a problem. Now, to your left is what we call the pedestal."

Burne pointed to a boxy structure that protruded between the two seats. There were a half-dozen levers in slots on the pedestal. "Now, from right to left, flaps - slats, two throttles for the engines, spoilers, brakes, thrusters. Slats and flaps are controlled by that lever nearest you, the one with the little metal cover over it. See it?"

"I see it," Richman said.

"Good. Flip up the cover, and engage the slats."

"Engage the ..."

"Pull the slats lever down," Burne said.

Richman flicked up the cover, and struggled for a moment to move the lever.

"No, no. Grab it firmly, pull it up, then right, then down," Burne said. "Just like a gearshift on a car."

Richman closed his fingers around the handle. He pulled the lever up, across, and down. There was a distant hum.

"Good," Burne said. "Now, look at your display. See that amber SLATS EXTD indicator? It's telling you the slats are coming out of the leading edge. Okay? Takes twelve seconds to fully extend. Now they're out, and the indicator is white and says SLATS."

"I see," Richman said.

"Okay. Now retract the slats."

Richman reversed his actions, pushing the lever up, sliding it left and down to locked position, then closing the cover over the handle.

"That," Bume said, "is a commanded slats extension."

"Okay," Richman said.

"Now, let's perform an uncommanded slats extension."

"How do I do that?"

"Any way you can, pal. For starters, hit it with the side of 'your hand."

Richman reached across the pedestal, brushing the lever with his left hand. But the cover protected it. Nothing happened.

"Come on, hit that sucker."

Richman swung his hand laterally back and forth, banging against the metal. He hit it harder and harder each time, but nothing happened. The cover protected the handle; the slats lever remained up and locked.

"Maybe you could knock it with your elbow," Burne said. "Or tell you what, try this clipboard here," he said, pulling a clipboard from between the seats, and giving it to Richman. "Go on, give it a good whack. I'm looking for an accident here."

Richman struck the lever with the clipboard. It clanged against the metal. He turned the clipboard and pushed the lever with one edge. Nothing happened.

"You want to keep trying?" Burne said. "Or are you starting to get the point? It can't be done, Clarence. Not with that cover in place."

"Maybe the cover wasn't in place," Richman said.

"Hey," Burne said, "that's good thinking. Maybe you can knock the cover up, by accident. Try that with your clipboard, Clarence."

Richman swung the clipboard at the edge of the cover. But the surface was smoothly curved, and the clipboard just slid off. The cover remained closed.

"No way to do it," Burne said. "Not by accident. So. What's the next thought?"

"Maybe the cover was already up."

"Good idea," Burne said. "They're not supposed to be flying with the cover up, but who the hell knows what they did. Go ahead and lift die cover up."

Richman lifted the cover up on its hinge. The handle was now exposed.

"Okay, Clarence. Go to it."

Richman swung his clipboard at the handle, banging it hard, but with most lateral movements, the raised cover still acted as a protection. The clipboard hit die cover before it struck the handle. Several times on impact, the cover dropped back down again. Richman had to keep stopping to lift the cover up again before he could proceed.

"Maybe if you used your hand," Burne suggested.

Richman tried swiping at the handle with his palm. In a few moments, the side of his hand was red, and the lever remained firmly up and locked.

"Okay," he said, sitting back in the seat. "I get the point."

"It can't be done," Bume said. "It simply can't be done. An uncommanded slats deploy is impossible on this aircraft. Period."

From outside the cockpit, Doherty said, "Are you guys finished screwing around? Because I want to pull the recorders and go home."

As they came out of the cockpit, Burne touched Casey on the shoulder and said, "See you a minute?"

"Sure," she said.

He led her back in the plane, out of earshot of the others. He leaned close to her and said, "What do you know about that kid?"

Casey shrugged. "He's a Norton relative."

"What else?"

"Marder assigned him to me."

"You check him out?"

"No," Casey said. "If Marder sent him, I assume he's fine."

"Well, I talked to my friends in Marketing," Burne said. "They say he's a weasel. They say, don't turn your back on him."

"Kenny..."

"I'm telling you, something's wrong with that kid, Casey. Check him out."

With a metallic whir from the power screwdrivers, the floor panels came away, revealing a maze of cables and boxes under the cockpit.

"Jesus," Richman said, staring.

Ron Smith was directing the operation, running his hand over his bald head nervously. "That's fine," he said. "Now get the panel to the left."

"How many boxes we got on this bird, Ron?" Doherty said.

"A hundred and fifty-two," Smith said. Anybody else, Casey knew, would have to thumb through a thick sheaf of schematics before he answered. But Smith knew the electrical system by heart.

"What're we pulling?" Doherty said.

"Pull the CVR, the DFDR, and the QAR if they got one," Smith said.

"You don't know if there's a QAR?" Doherty said, teasing him.

"Optional," Smith said. "It's a customer install. I don't think they put one in. Usually on the N-22 it's in the tail, but I looked, and didn't find one."

Richman turned to Casey; he was looking puzzled again. "I thought they were getting the black boxes."

"We are," Smith said.

"There's a hundred and fifty-two black boxes?"

"Oh hell," Smith said, "they're all over the aircraft. But we're only after the main ones now - the ten or twelve NVMs that count."

"NVMs," Richman repeated.

"You got it," Smith said, and he turned away, bending over the panels.

It was left to Casey to explain. The public perception of an aircraft was that it was a big mechanical device, with pulleys and levers that moved control surfaces up and down. In the midst of this machinery were two magic black boxes, recording events in the flight. These were the black boxes that were always talked about on news programs. The CVR, the cockpit voice recorder, was essentially a very sturdy tape deck; it recorded the last half hour of cockpit conversation on a continuous loop of magnetic tape. Then there was the DFDR, the digital flight data recorder, which stored details of the behavior of the airplane, so that investigators could discover what had happened after an accident

But this image of an aircraft, Casey explained, was inaccurate for a large commercial transport. Commercial jets had very few pulleys and levers - indeed, few mechanical systems of any sort. Nearly everything was hydraulic and electrical. The pilot in the cockpit didn't move the ailerons or flaps by force of muscle. Instead, the arrangement was like power steering on an automobile: when the pilot moved the control stick and pedals, he sent electrical impulses to actuate hydraulic systems, which in turn moved the control surfaces.

The truth was that a commercial airliner was controlled by a network of extraordinarily sophisticated electronics - dozens of computer systems, linked together by hundreds of miles of wiring. There were computers for flight management, for navigation, for communication. Computers regulated the engines, the control surfaces, the cabin environment.

Each major computer system controlled a whole array of sub-systems. Thus the navigation system ran the ILS for instrument landing; the DME for distance measuring; the ATC for air traffic control; the TCAS for collision avoidance; the GPWS for ground proximity warning.

In this complex electronic environment, it was relatively easy to install a digital flight data recorder. Since all the commands were already electronic, they were simply routed through the DFDR and stored on magnetic media. "A modern DFDR records eighty separate flight parameters every second of the flight."

"Every second? How big is this thing?" Richman said.

"It's right there," Casey said, pointing. Ron was pulling an orange-and-black striped box from the radio rack. It was the size of a large shoe box. He set it on the floor, and replaced it with a new box, for the ferry flight back to Burbank.

Richman bent over, and lifted the DFDR by one stainless-steel handle. "Heavy."

That's the crash-resistant housing," Ron said. "The actual doohickey weighs maybe six ounces."

"And the other boxes? What about them?"

The other boxes existed, Casey said, to facilitate maintenance. Because the electronic systems of the aircraft were so complicated, it was necessary to monitor' the behavior of each system in case of errors, or faults, during flight. Each system tracked its own performance, in what was called Non Volatile Memory. "That's NVM "

They would download eight NVM systems today: the Flight Management Computer, which stored data on the flight plan and the pilot-entered waypoints; the Digital Engine Controller, which managed fuel bum and powerplant; the Digital Air Data Computer, which recorded airspeed, altitude, and overspeed warnings ...

"Okay," Richman said. "I think I get the point."

"None of this would be necessary," Ron Smith said, "if we had the QAR."

"QAR?"

"It's another maintenance item," Casey said. "Maintenance crews need to come on board after the plane lands, and get a fast readout of anything that went wrong on the last leg."

"Don't they ask the pilots?"

"Pilots will report problems, but with a complex aircraft, there may be faults that never come to their attention, particularly since these aircraft are built with redundant systems. For any important system like hydraulics, there's always a backup - and usually a third as well. A fault in the second or third backup may not show in the cockpit So the maintenance crews come on board, and go to the Quick Access Recorder, which spits out data from the previous flight They get a fast profile, and do the repairs on the spot"

"But there's no Quick Access Recorder on this plane?"

"Apparently not" she said. "It's not required. FAA regulations require a CVR and a DFDR. The Quick Access Recorder is optional. Looks like the carrier didn't put one on this plane."

"At least I can't find it" Ron said. "But it could be anywhere."

He was down on his hands and knees, bent over a laptopcomputer plugged into the electrical panels. Data scrolled down the screen.

A/S  PWR TEST 00000010000

AIL  SERVO  COMP 00001001000

ADA  INV 10200010001

CFDS  SENS  FAIL 00000010000

CRZ  CMD MON   INV 10000020100

EL  SERVO  COMP 00000000010

EPR/N1   TRA-1 00000010000

FMS  SPEED  INV 00000040000

PRESS  ALT   INV 00000030000

G/S   SPEED ANG 00000010000

SLAT XSIT T/0 00000000000

G/S  DEV  INV 00100050001

GND  SPD  INV 00000021000

TAS   INV 00001010000

"This looks like data from the flight control computer," Casey said. "Most of the faults occurred on one leg, when the incident occurred."

"But how do you interpret this?" Richman said.

"Not our problem," Ron Smith said. "We just offload it and bring it back to Norton. The kids in Digital feed it to mainframes, and convert it to a video of the flight."

"We hope," Casey said. She straightened. "How much longer, Ron?"