The report offered a strong defense of the 737 rudder system and explained why it would not have malfunctioned on Flight 427. Nearly every place that the report mentioned the possibility of a jam, it used the word “hypothetical.” (“Hypothetical scenarios exist that would provide a full rudder deflection to blowdown. However, very specific conditions are required for each hypothetical failure scenario.”) The word appeared at least nineteen times.
But when Boeing discussed pilot error, the word “hypothetical” was not used. The report said airline pilots were often startled by wake turbulence, overreacted, and stomped on the rudder. That was a fact. In Boeing’s view, pilot mistakes were not hypothetical.
To show how a pilot could keep his foot on the pedal, Boeing cited the problem of “unintended acceleration,” when a driver of an automobile mistakenly stomps on the gas pedal instead of the brake, a mistake that has destroyed front windows in many 7-Elevens.
The company offered a scenario showing how the pilots could have caused the crash: Emmett was so relaxed before the wake turbulence that he referred to the Jetstream in “a drawn-out, feigned French accent.” When the plane was jostled by the wake, Emmett pushed on the rudder pedal once or twice to level the wings. He was so startled that he did not realize that he kept pressing on the rudder. He then pulled back on the stick, which stalled the airplane and made it crash.
Boeing did not discuss the dangers of the crossover point, or the fact that the pilots had not been warned about it. But the company’s submission said that Emmett and Germano could have recovered by simply turning the wheel to the right.
The message was subtle but clear: The 132 people on the plane would be alive today if the pilots had done the right thing.
In a surprise to everyone in the investigation, the FAA chimed in with a submission a week after Boeing did. The FAA was always a party in NTSB investigations, but it rarely made a submission. Its relations with the safety board were rocky, so FAA officials were selective about when to pick fights. In most investigations, the FAA sat quietly and took its licking when criticized by the NTSB. But this time the agency adopted an unusual tactic: It told the NTSB there wasn’t enough evidence to name the probable cause.
“The FAA, upon review of the evidence, cannot conclude that a failure mode… has been identified. Any causal findings, to be legitimate, must have conclusive evidence to support findings of a hardover or reversed rudder. Such evidence has yet to be found.”
Haueter was struck by how much the FAA submission sounded like Boeing’s. In his view, the FAA was just posturing to protect itself. If the NTSB blamed the airplane and said it didn’t meet federal safety standards, everyone would want to know why the FAA hadn’t grounded the plane. He thought the FAA was trying to preempt the NTSB by saying there was insufficient evidence.
Haueter believed he had enough evidence. No, he didn’t have absolute proof that the valve had jammed. But he had an extremely strong case that it was the most likely cause. Now he had to convince the most important audience: the board members.
The report was marked “DRAFT—Confidential” when it went to board members in early February 1999. It was five hundred pages long—so big that it had to be held together with a rubber band instead of the usual binder clip. It was the longest crash report in the NTSB’s history.
The probable cause statement was succinct. It said the pilots lost control because the rudder reversed. The report was sharply critical of the 737, saying the plane was not as safe as it should be. Boeing was fixing the rudder valve to prevent a reversal, the report said, but that was “not an adequate fleet-wide remedy.” The report warned that the plane was still vulnerable to rudder malfunctions that could have “catastrophic results,” and it said there could be additional 737 rudder problems that had not been discovered.
The report said the FAA should replace the unique rudder valve with one that is “truly redundant,” which could be done by adding a second valve or splitting the 737’s single rudder panel into two.
The report was very much a group effort. Haueter and his investigators had written long sections that had been compiled and edited by an NTSB report writer. But the person with the greatest influence over it was Bernard Loeb, Haueter’s boss.
Loeb was an intense, opinionated man who had become the NTSB’s director of aviation safety midway through the investigation. He had an in-your-face style and wasn’t shy about telling people they were wrong. Peter Goelz, the safety board’s managing director, recalled that once, during an argument about Flight 427, Loeb had called him an idiot. Loeb was renowned for being a micromanager. George Black, an NTSB board member, jokingly called Loeb and his staff “the Borg,” after the evil force on Star Trek that controls the brains of drones.
Some people at the NTSB thought that Haueter relinquished too much power to Loeb and didn’t challenge him enough. Haueter himself was frustrated that Loeb had such a heavy hand, but Haueter felt that he went as far as he could. He stood up for the ideas that mattered, but ultimately he had to respect that Loeb was his boss.
Indeed, Loeb’s aggressive style was valuable. Haueter’s “Holy Mackerels” and his friendly disposition sometimes made him seem overly tentative. Loeb became the strong advocate the investigation needed at the end, someone with status and a loud voice who could get the final report approved. Loeb’s style was in keeping with the safety board’s culture of argument. The shouting matches got all the conflicts out into the open. A weak theory—or a weak investigator—didn’t last long.
Loeb was pushing a theory that was like a three-legged stool. He thought that, individually, none of the three incidents gave the NTSB enough evidence to blame the problem on a rudder reversal but, collectively, the three provided enough proof that the rudder had jammed and reversed.
New simulations by NTSB computer whiz Dennis Crider showed that a reversal would explain all three incidents. Crider’s most important finding was this: The rates of rudder movement on the three planes were nearly identical. That was powerful evidence. It was highly unlikely that three pilots on three different days in three different airplanes would move the rudder at exactly the same speed.
Loeb and Haueter now were focused on counting votes. Goglia had disqualified himself from voting, but they still needed three of the four remaining board members. If Francis voted against them, they needed everyone else.
Haueter was nervous that they wouldn’t get the votes. He had heard rumors that the board members were split 2-2 on whether to blame the plane. They were said to be skeptical about the report and wanted to blame the crash on “undetermined reasons.”
Undetermined reasons.
Those were the big blue words on the cover of the Colorado Springs report, and Haueter winced at the thought of them on his report. If they appeared on the Flight 427 report, Haueter feared he would be remembered “as the guy who flubbed it.” Even worse, the 737 would continue flying with its elusive rudder problem, and the NTSB would have no leverage to force Boeing to fix it.
Haueter was concerned that Crider’s findings were not having an impact with the board. Crider had to keep revising them as he made last-minute discoveries, but the numbers always added up to the same conclusion—a rudder reversal. Haueter was afraid it looked to the board members like the investigation was in chaos and was biased toward that conclusion.
Haueter and Loeb were also frustrated by Phillips, who was reluctant to blame the crashes on rudder reversals. Phillips said the reversals were a plausible explanation, but that he didn’t have enough solid evidence to be definitive. “I can’t lay a part in front of you and say this is what broke,” he said. He felt the NTSB lost credibility if it pushed too hard for a cause when the evidence wasn’t solid.