Hearing the Last of Lost Lives

Until today, the U.S. government had never played the cockpit tapes of an air disaster for families who lost loved ones, insisting that the sounds would be too raw.

Now, families of the 40 passengers and crew of United Flight 93 will hear the 30 minutes of tension and chaos that preceded the crash of the jetliner into a Pennsylvania field Sept. 11. They felt they had a right to listen, to know. Their relatives apparently tried to take back control of the plane from four hijackers, and thereby thwarted another terrorist attack.

As they listen, the families will enter a zone normally inhabited only by a small corps of investigators hardened to bitter reality. Like coroners with headphones, the investigators seek to uncover the hidden causes of tragedies through painstaking analysis of the most minute clues.

They work from a National Transportation Safety Board laboratory in Washington that is stacked with mangled recorders, reminders of life’s fragility. The listening room itself is spartan. There is a table and chairs, with headphones at each seat. At the end of the table sits a large computer monitor, so everyone can see as an NTSB technician transcribes what is heard on the tape.

Investigators regard this room as the agency’s inner sanctum, a workplace in which they witness struggles that reveal both the harsh finality of death and the power of the human will to live.

“You are really very close to the soul,” said Malcolm Brenner, an NTSB psychologist who specializes in voice analysis. “Speech is very close to how a person thinks.”

Brenner believes he has gotten to know some pilots as one would a friend by repeatedly listening to snatches of the last half-hour of their lives to figure out how they died.

He listened hundreds of times over four years to the cockpit tapes of USAir Flight 427, which went down near Pittsburgh in 1994, killing all 132 aboard.

Finally, he was able to match a series of grunting sounds by the co-pilot with data replicating a malfunction of the Boeing 737’s rudder. The co-pilot was grunting as he fought to overcome an unexpected, catastrophic turn in what would otherwise have been a routine landing. Brenner’s work helped bring about a redesign of the rudder system on the airliner, the world’s most popular.

When the Federal Aviation Administration first required voice recorders in the mid-1960s, investigators could do little more than try to make out the conversation. Now some tapes are studio quality, Brenner said.

Computer analysis allows measurement of the level of stress in a pilot’s voice. Specific scientific criteria have been developed to identify panic in a human voice. The panic response has never been heard with pilots undergoing training in a simulator, Brenner said, only in an actual crash.

Investigators correlate the words and exclamations of pilots with information on controls and flight conditions from the plane’s second “black box,” the flight data recorder. Clicks, thumps, vibrations and other mechanical noises can also be of significance, and the NTSB maintains a sound library to help identify them. Both recorders were recovered from the Flight 93 crash.

The cockpit tapes often reveal the best of people under the worst of circumstances, investigators say.

The cockpit recorder of Alaska Airlines Flight 261 showed that the pilots kept struggling to regain control of the plane even after its horizontal stabilizer broke away. It plunged upside-down into the Pacific Ocean off Ventura County on Jan. 31, 2000, killing all 88 aboard.

In the heroism of Flight 93’s passengers, veteran investigators see the same kind of resolve.

“You have a problem and you try to solve it without any foreknowledge of how much time you have to live,” said Douglas Wiegmann, a professor of aviation human factors at the University of Illinois and a former NTSB psychologist. “I believe these passengers thought they could take control and land the plane. They weren’t trying to find another way to die; they were trying to save the situation.”

“The passengers who took action were of the same mind-set as the people who fly airplanes,” agreed Paul McCarthy, an airline captain who represents the pilots’ union in investigations. That mind-set? “Pilots are survivors,” he said.

Even so, there comes a moment of dread on cockpit tapes. An exclamation, an invocation, a lament, a curse. Then voices cease and an awful silence reigns.

“The most chilling part is when it ends,” said David F. Thomas, a former chief investigator for the FAA. “All of a sudden there’s silence, and you know it’s over.”

The families of Flight 93 have been told what to expect. “The content is violent and very distressing,” said an FBI memo to the families. “Once the [recording] is heard, it may be impossible to forget the sounds and images it evokes.”

Alice Hoglan, whose son Mark Bingham is believed to have been one of the rebel passengers, said at least one family has been advised by the FBI not to attend, presumably because the violence done to their relative is so distinct.

The recording reportedly opens with the voice of a person pleading for mercy, Hoglan said. There is aircraft noise. There is a commotion. The hijackers apparently try to maneuver the plane to disrupt an assault by passengers on the cockpit.

Air safety investigators are divided over whether the families of Flight 93 should listen to the tape.

“It’s a logical request,” Wiegmann said. “Most of the surviving family members remember the voice of their deceased loved one. Some of [the passengers] may have charged the cockpit. Listening to it will help the family members better understand what caused the death of the person they are mourning, rather than getting secondhand information about what is supposedly on that tape.”

It’s not about logic, responded Greg Feith, a former NTSB air crash investigator. “I would tell them, ‘You don’t want to hear this, because you may hear something that may haunt you the rest of your life.’ ”

Jack Grandcolas agrees. His wife, Lauren, called him from the hijacked plane that morning and left a message of comfort and encouragement on their answering machine. Then she gave her phone to another passenger, an anguished young woman who was able to reach her family.

“She was an incredible woman, helping others to be strong,” Grandcolas said. “That is the thing I would rather focus on. I have no desire to pursue hearing” the cockpit tape.

But Lauren’s younger sister Vaughn Lohec feels a duty to learn everything she can about the events on the plane. She plans to listen to the tape, if she can get up the nerve.

“Even within our family network, we have differences of opinion,” Lohec said. “I just don’t know if I can go through the rest of my life without listening.”

The FBI and Justice Department decision to allow the families to listen came after a campaign by Deena Burnett. Her husband, Tom, a Bay Area businessman, was on the flight from Newark, N.J., to San Francisco and is believed to have been one of the leaders of the passenger revolt.

Another reason for holding a listening session is that authorities are considering playing the tape in court. Hoglan said FBI officials have told the families the tape will be evidence in the trial of Zacarias Moussaoui, who is suspected of having been a missing member of the Flight 93 hijacking team.

FBI officials and federal prosecutors declined to comment. NTSB experts also declined to answer any questions about the technical support they have provided in the investigation.

If the tape is eventually played in court, the types of voice and sound analysis now possible will increase jurors’ understanding of what happened.

Noise that may seem like pandemonium can be stopped, slowed down and correlated with movements of the aircraft. Every sound is a potential clue.

In the 1996 crash of TWA Flight 800 off Long Island, in which 230 people died, the cockpit tape showed the pilots were unaware of any problems before the catastrophe. “It was a perfect, do-it-every-day flight,” said James Cash, the NTSB’s chief technical advisor on transportation recorders.

An abnormal noise registered on the last 120 milliseconds of the tape, a sound like a crash, or maybe an explosion. Was it a bomb? A missile strike? Cash spent three years analyzing the sound “signature” of the noise. He blew up part of a scrapped Boeing 747, recording that sound for comparison.

His findings supported the conclusion that a mechanical defect ignited fuel vapors in the plane’s center tank. The 120-millisecond noise was really a compressed stream of sound: the fuel tank rupture, the structural failure of the aircraft, the ripping of wires and the loss of power to the recorder.

“High explosives develop quickly and don’t last very long,” Cash said. “A fuel-air explosion like this takes a little longer to develop.”

When EgyptAir Flight 990 crashed off New England in 1999, killing 217, cockpit tapes caught the co-pilot, alone in the cockpit, reciting a prayer in Arabic as he put the plane into a dive. That was strange enough. But even more startling to Bernard Loeb, then chief of the NTSB’s aviation safety office, was what happened after the plane’s captain managed to scramble back.

Immediately, the captain began to trouble-shoot the problem--the classic response of a pilot who encounters an unexpected crisis. The co-pilot kept intoning his prayer.

“He didn’t say, ‘There’s something wrong. . . . I can’t pull the nose up,’ ” Loeb said. “That’s what anybody who was in the situation would say.” The flight data recorder showed that the co-pilot then shut off the engines. The captain pulled back on his control yoke to bring the nose up; the co-pilot pushed forward on his.

Analysis of the Flight 93 tape should be able show who was at the controls and whether the passengers were indeed able to get into the cockpit.

The prospect of the tape eventually being played in court is raising concerns among family members and pilots’ organizations that an audio version might become public and even be posted on the Internet. In an NTSB air crash investigation, the audio recordings are protected from release by federal law, although edited transcripts are eventually made public.

“It’s basically a violent murder, and that’s an impression I would prefer not to leave in my mind,” Grandcolas said. “I’m sure eventually it will be in the public domain, but I don’t know if I’d be able to deal with it.”

McCarthy, the airline captain who also serves as an accident investigator, said pilots will do everything possible to block widespread release of the tape. Pilots’ groups are considering asking the judge to close the courtroom if the tape is played.

“Congress intended for cockpit voice recordings to simply never be played for the public,” McCarthy said. “We are going to petition if the prosecution decides to use it in this case. It’s not a matter of balancing competing rights. If you’re going to compel me to record my voice, you owe me the common decency of keeping it private.”