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?"
Chapter 5
'Ten minutes, max," Smith said.
"Oh sure," Doherty said, from inside the cockpit. 'Ten minutes max, oh sure. Not that it matters. I wanted to beat rush hour traffic but now I guess I can't. It's my kid's birthday, and I won't be home for the party. My wife's going to give me hell."
Ron Smith was starting to laugh. "Can you think of anything else that might go wrong, Doug?"
"Oh sure. Lots of things. Salmonella in the cake. All the kids poisoned," Doherty said.
Casey looked out the door. The maintenance people had all climbed off the wing. Burne was finishing up his inspection of the engines. Trung was loading the DFDR into the van.
It was time to go home.
As she started down the stairs, she noticed three Norton Security vans parked in a corner of the hangar. There were about twenty security guards standing around the plane, and in various parts of the hangar.
Richman noticed, too. "What's this about?" he said, gesturing to the guards.
"We always put security on the plane, until it's ferried to the plant," she said.
"That's a lot of security."
"Yeah, well." Casey shrugged. "It's an important plane."
But she noticed that the guards all wore sidearms. Casey couldn't remember seeing armed guards before. A hangar at LAX was a secure facility. There wasn't any need for the guards to be armed.
Was there?
BLDG 64
4:30 P.M.
Casey was walking through the northeast corner of Building 64, past the huge tools on which the wing was built. The tools were crisscrossed blue steel scaffolding, rising twenty feet above the ground. Although they were the size of a small apartment building, the tools were precisely aligned to within a thousandth of an inch. Up on the platform formed by the tools, eighty people were walking around, putting the wing together.