Haueter thought his friend was being wishy-washy. He said Phillips would go out to Boeing and come back sounding as though he had been brainwashed. He kept telling Phillips that they had a strong case and had some latitude because they only had to come up with a probable cause.
As Crider scrambled to finish the new computer simulations, Boeing, which knew all the angles to work at the NTSB, was busy lobbying the board members. Boeing had taken each of the board members for a ride in the M-Cab simulator to show how easily Flight 427’s pilots could have saved the airplane. The company also had provided the board members with a video about the plane that discussed the extensive plans for safety improvements.
USAir was doing its own lobbying, trying to persuade the board members that the plane was at fault and thus putting the airline in the odd position of arguing that every 737—including the 200 that the airline itself operated—had a safety problem. A USAir official came to the NTSB offices and showed the board members a horrifying video that combined a computer animation of the crash with the actual cockpit voice tape. It gave board members a chance to see and hear two pilots fight and scream and then die, to emphasize USAir’s position that the pilots had no idea what the plane was doing.
Haueter and Loeb figured they had a good chance with two of the board members—Chairman Jim Hall and John Hammerschmidt. Hall did not have the technical background to understand the intricacies of the valve, but he had been suspicious of Boeing and seemed to have high regard for the staff recommendations. Hammerschmidt, a shy man who was virtually invisible as a board member, was also expected to go with the staff recommendation.
Bob Francis was shaping up to be just as difficult as Haueter had feared. He said the report was too absolute about the rudder reversal and that it was overly critical of the FAA. In his view, the NTSB had “fairly shaky evidence” and should not be so critical. He met with Hall in the chairman’s office and said he would vote against the report unless it was toned down.
The other key board member was George Black, a brainy highway engineer from suburban Atlanta. He spent far more time studying the evidence than the other board members and filled a spare office with engineering reports, maps of the plane’s radar track, and a small plastic model of a 737 that he used to demonstrate the crash. He scrawled a sign for the door that said, THE WAR ROOM.
No one was sure how Black would vote. He liked to play devil’s advocate, throwing out new ideas that often contradicted each other. He liked to tease Boeing executives about the possibly dismal future for the 737, their best-selling product, if the rudder was blamed for the crash. “Boeing has no corporate sense of humor,” he grumbled.
Black was convinced that the plane had a problem in its rudder system. He had discussed the crash with pilots and engineers and decided that Emmett and Germano would not stomp on a rudder pedal and hold it to their death. He was especially impressed with Crider’s simulations and Brenner’s work matching the grunts to the precise moments at which the rudder appeared to reverse. He was not persuaded by Boeing’s M-Cab ride and thought it was understandable that the pilots—unaware of the dangers of the crossover point—could lose control of the plane.
Yet he thought the report was too strong. “Tom and Bernie come in here thumping the report like it were the Torah,” he said, but they still had no proof. He said the board members had some latitude because they were naming the probable cause, but he wondered, “At what point does this rise to the level ‘probable’?” He also was concerned that Crider’s simulations were a little too perfect, matching the reversal scenario every time, even when Crider had to make adjustments. Haueter assured Black that the reversal scenario was just one of several that could match, but Black was still wary. He worried that Loeb and his deputies were too adamant about the plane.
Suddenly, right in the midst of the deliberations, there was another 737 scare: a USAir MetroJet plane had a strange rudder incident.
Shortly before noon on February 23, 1999, MetroJet Flight 2710 was cruising at 33,000 feet over Maryland when the pilots noticed the wheel suddenly turn to the left. They quickly realized the autopilot was turning the wheel to compensate for rudder movement. But the pilots had not touched the rudder pedals. The copilot then put his feet on the pedals and discovered that they were displaced to the right. He turned off the autopilot and pushed on the left pedal to return the rudder to the center position, but the pedals seemed to be jammed.
The pilots quickly followed an emergency procedure that had been developed by Cox and another USAir pilot. They turned off the yaw damper, the device that makes small adjustments to the rudder, and activated the standby rudder system, which uses a backup hydraulic valve instead of the main one. The rudder pedals moved back to the center.
The pilots announced to passengers that they had a flight control problem and then landed at Baltimore-Washington International Airport. After they parked at the gate and everyone got off, a platoon of investigators from the safety board, the FAA, ALPA, and USAir arrived and began removing evidence. They took the two flight recorders, the yaw damper coupler, the rudder PCU and its valve-within-a-valve, and one liter of hydraulic fluid.
The flight recorder showed that the incident was very different from the Pittsburgh crash. Instead of the fast-moving hardover, the MetroJet rudder had moved slowly to its limit. One FAA official called it “a slow-over.” The incident was even more curious because the plane had one of the new, improved rudder valves that prevented a reversal, and the valve showed no signs of a jam.
The incident left Haueter and Loeb scratching their heads. It added urgency to their work in the final weeks before the board meeting, but it also raised some troubling questions. Had they found all the problems that might lurk inside the rudder system? Did the valve have a different flaw that they had not uncovered? Had there been a jam somewhere else in the PCU? Cox, who had blamed the USAir crash on a “gremlin” in the plane, said the MetroJet incident showed there was “another gremlin in the tail of the 737.”
It also revealed a major shortcoming of all their work. Haueter’s team had some of the smartest engineers in aviation, supplemented by the Greatest Minds in Hydraulics. Boeing had deployed its best and brightest and called in people with decades of experience. But for all that brainpower, they still had not come up with a definitive answer about what had happened to Flight 427. That was remarkable because they were not dealing with a million lines of computer code or a newfangled electronic gadget. They were dealing with an old mechanical device—an ordinary valve designed when John F. Kennedy was president. And now, more than thirty years later, they were struggling to understand the gadget and the myriad ways it could work.
“I don’t even think the inventors understand it,” said Steve O’Neal, the FAA flight test engineer. He said the MetroJet incident suggested that more changes were needed in the rudder system. “We just hope another 737 doesn’t come screaming out of the sky in the meantime.”
George Black, the NTSB board member, was worried that the MetroJet incident revealed that the investigators had been too fixated on the valve and had missed a problem elsewhere in the plane. He knew they had ruled out hundreds of possibilities—everything from bird strikes to the fat guy theory—but he was still worried that they were missing the real problem. He was concerned that they would approve the report and then end up having to revise it later. “Are we premature?” he asked. “We want to make sure we don’t start off down some path and decide it was unnecessary.”