"Okay," she said.

"This is a precaution," Marder said. "Nothing more."

"Okay," she said.

"Get some sleep," Marder said, and hung up.

She awoke uneasily, before the alarm went off. She pulled on a bathrobe, walked to the kitchen to turn on the coffee, and looked out the front window. The blue sedan was still parked on the street, the men inside. She considered taking her five-mile run, she needed that exercise to start her day, but decided against it. She knew she shouldn't feel intimidated. But there was no point in taking chances.

She poured a cup of coffee, sat in the living room. Everything looked different to her today. Yesterday, her little bungalow felt cozy; today, it felt small, defenseless, isolated. She was glad Allison was spending the week with Jim.

Casey had lived through periods of labor tension in the past; she knew that the threats usually came to nothing. But it was wise to be cautious. One of the first lessons Casey had learned at Norton was that the factory floor was a very tough world- tougher even than the assembly line at Ford. Norton was one of the few remaining places where an unskilled high school graduate could earn $80,000 a year, with overtime. Jobs like that were scarce, and getting scarcer. The competition to get those jobs, and to keep them, was fierce. If the union thought the China sale was going to cost jobs, they could very well act ruthlessly to stop it.

She sat with the coffee cup on her lap and realized she dreaded going to the factory. But of course she had to go. Casey pushed the cup away, and went into the bedroom to dress.

When she came outside and got into her Mustang, she saw a second sedan pull up behind the first. As she drove down the street, the first car pulled out, following her.

So Marder had ordered two sets of guards. One to watch her house, and one to follow her.

Things must be worse than she thought.

She drove into the plant with an uncharacteristic feeling of unease. First shift had already started; the parking lots were full, acres and acres of cars. The blue sedan stayed right behind her as Casey pulled up to the security guard at Gate 7. The guard waved her through and, by some unseen signal, allowed the blue sedan to follow directly, without putting the barrier down. The sedan stayed behind her until she parked at her spot in Administration.

She got out of the car. One of the guards leaned out the window. "Have a nice day, ma'am," he said.

"Thanks. I will."

The guard waved. The sedan sped off.

Casey looked around at the huge gray buildings: Building 64 to the south. Building 57 to the east, where the twinjet was built. Building 121, the Paint Shed. The maintenance hangars in a row off to the west, lit by the sun rising over the San Fernando Mountains. It was a familiar landscape; she'd spent five years here. But today she was uncomfortably aware of the vast dimensions, the emptiness of the place in early morning. She saw two secretaries walking into the Administration building. No one else. She felt alone.

She shrugged her shoulders, shaking off her fears. She was being silly, she told herself. It was time to go to work.

Rob Wong, the young programmer at Norton Digital Information Systems, turned away from the video monitors and said, "Sorry, Casey. We got the flight recorder data-but there's a problem."

She sighed. "Don't tell me."

"Yeah. There is."

She was not really surprised to hear it. Flight data recorders rarely performed correctly. In the press, these failures were explained as the consequence of crash impacts. After an airplane hit the ground at five hundred miles an hour, it seemed reasonable to think that a tape deck might not be working.

But within the aerospace industry, the perception was different. Everyone knew flight data recorders failed at a very high rate, even when the aircraft didn't crash. The reason was that the FAA did not require they be checked before every flight. In practice, they were usually function-checked about once a year. The consequence was predictable: the flight recorders rarely worked.

Everybody knew about the problem: the FAA, the NTSB, the airlines, and the manufacturers. Norton had conducted a study a few years back, a random check of DFDRs in active service. Casey had been on that study committee. They'd found that only one recorder in six worked properly.

Why the FAA would mandate the installation of FDRs, without also requiring that they be in working order before each flight, was a frequent subject of late-night discussion in aerospace bars from Seattle to Long Beach. The cynical view was that malfunctioning FDRs were in everybody's interest. In a nation besieged by rabid lawyers and a sensational press, the industry saw little advantage to providing an objective, reliable record of what had gone wrong.

"We're doing the best we can, Casey," Rob Wong said. "But the flight recorder data is anomalous."

"Meaning what?"

"It looks like the number-three bus blew about twenty hours before the incident, so the frame syncs are out on the subsequent data."

"The frame syncs?"

"Yeah. See, the FDR records all the parameters in rotation, in data blocks called frames. You get a reading for, say, airspeed, and then you get another reading four blocks later. Airspeed readings should be continuous across the frames. If they're not, the frames are out of sync, and we can't build the flight. I'll show you."

He turned to the screen, pressing keys. "Normally, we can take the DFDR and generate the airplane in' tri-axis. There's the plane, ready to go."

A wire-frame image of the Norton N-22 widebody appeared on the screen. As she watched, the wire frame filled in, until it took on the appearance of an actual aircraft in flight.

"Okay, now we feed it your flight recorder data…"

The airplane seemed to ripple. It vanished from the screen, then reappeared. It vanished again, and when it reappeared the left wing was separated from the fuselage. The wing twisted ninety degrees, while the rest of the airplane rolled to the right. Then the tail vanished. The entire plane vanished, reappeared again, vanished again.

"See, the mainframe's trying to draw the aircraft," Rob said, "but it keeps hitting discontinuities. The wing data doesn't fit the fuse data which doesn't fit the tail data. So it breaks up."

"What do we do?" she said.

"Resync the frames, but that'll take time."

"How long? Marder's on my back."

"It could be a while, Casey. The data's pretty bad. What about the QAR?"

"There isn't one."

"Well, if you're really stuck, I'd take this data to Flight Sims. They have some sophisticated programs there. They may be able to fill in the blanks faster, and tell you what happened."

"But Rob-"

"No promises, Casey," he said. "Not with this data. Sorry."