Flight 232: A Story of Disaster and Survival (9 page)

The combustion chamber is a hollow torus of metal, a shape like a doughnut. In cross section, it isn’t round as a doughnut is. It is elongated. That cross section measures seven and a half inches by a bit more than three inches. It has numerous small holes in it forming complex patterns. The highly compressed air is forced through the holes all around the circumference, even as fuel is sprayed into the swirling air inside that hollow shape. The purpose of the shape of the combustion chamber is to keep the flame away from the driveshafts that run lengthwise through the center of the engine, connecting all the wheels. As jet fuel (a type of kerosene) enters the combustion chamber, it mixes with the compressed air, ignites, and blows exhaust gas back through turbine wheels, giving them their power. By way of two concentric driveshafts, one spinning inside the other, those turbine wheels transmit their power to the fans and compressors at the front of the engine.

If the airflow over one small section of a single blade is interrupted for any reason, it can create a turbulence that cascades down across the other blades, one after another, forming a blockage that makes it seem as if the air had turned to stone. It’s called a compressor surge or a compressor stall. When it happens, all the energy of those spinning wheels reverberates upon itself at once. Sometimes parts break. Thus could the air itself betray us. Modern turbine technology is a high-energy high-wire act in which any slight upset can bring the whole house of cards down with a bang. Yet this is what makes our system of air travel possible: working close to the limits of catastrophe.
Most people never fully realize
what sort of daredevils pioneered airline travel and still run it to this day.

When Boeing was about to introduce the 707
, the company arranged a demonstration of the prototype. It took place at Seafair on Lake Washington in Seattle. The Gold Cup hydroplane race was the big attraction at Seafair, but the Blue Angels also flew. In 1955, the International Air Transport Association, including every airline company, along with the Society of Aeronautical Engineers, held their annual meetings in Seattle during Seafair week. As it happened, Boeing’s factory and headquarters were close by.

With no customers on board, no orders for the craft, Bill Allen, the president of Boeing, had spent the equivalent of $137 million in 2013 dollars to develop the prototype of the 707. Designated 367-80, the plane was affectionately known as the Dash 80. When the time came for the flyby on that perfect summer day in August, the test pilot, Alvin M. “Tex” Johnston, with Jim Gannet as copilot and Bell Whitehead as engineer, rolled the plane as it passed over the Gold Cup course with two hundred thousand people watching. The big 707 was not inverted for long, but the effect was stunning.

Allen called Johnston to his office the next day and asked, “What did you think you were doing yesterday?”

Tex replied, “Selling the airplane.” He explained to his boss, “The airplane does not recognize attitude, providing a maneuver is conducted at one G.”

“You know that,” Allen said. “Now we know that. Don’t do it anymore.”

That evening Tex was summoned to Allen’s house for dinner, and when he arrived, a guest jumped up from his seat on the patio and “grabbed my Stetson by the brim with both hands, and jerked it down over my ears, saying, ‘You slow rollin’ S.O.B. Why didn’t you let me know? I would have been ridin’ the jump seat.’ ” The guest was Eddie Rickenbacker, the most successful fighter ace of World War I.

The founders of airlines, along with the airframe and engine manufacturers, had to be risk takers in part because of the expense of building and flying jet transport planes. In the industry they say that when a manufacturer sets out to design a new engine or a new airplane, the leaders are betting the company.
By the time United Flight 232 crashed
, only two jet airliners were known with any certainty to have made a profit: Boeing’s first offering, the 707, and its 727. The DC-10 would lose $2.5 billion (about twice that much in 2013 dollars) before McDonnell Douglas canceled production not long after the crash of 1819 Uniform.

Even so, the CF6-6 proved to be a reliable and successful engine.
It began powering commercial flights in 1971
, and some parts that were manufactured that year wound up on the number two engine that was mounted on 1819 Uniform as Dudley Dvorak looked out on the damaged tail. Technology takes time to mature, to become fine and smooth. Because a company must make money, mechanical inventions are often introduced before they have achieved that state of grace. United Flight 232 crashed because of a complex sequence of events, but that sequence began with a beautifully designed engine that was not quite ready to carry people around in the sky for quite as long as the manufacturer had promised it would.

And yet the CF6 in its many forms went on to become one of the best commercial aircraft engines ever made. Based on an engine that GE had developed for the military, the CF6 was chosen by both United and American Airlines in 1968 to power their brand new DC-10 aircraft. Since then, GE claims, that
engine has put in more hours of service
than any other gas turbine, “the equivalent of one engine running 24 hours a day, 365 days a year for more than 26,000 years.” By 1985, the CF6-6 had evolved into the CF6-80C2. That new version of the design was chosen to hang on the wings of
Air Force One
. Unfortunately, that development was of no help to the lovely old ship known as 1819 Uniform.

Now as United Flight 232 made its wandering way toward Sioux City, the crew may have wondered about all the things that could have gone wrong in that number two engine. The ship itself was fifteen years old. How many times had it taken off and landed? Many thousands of times, to be sure. And then there was the engine itself, known by the serial number 451-243: How long had it been on this plane? How often had it flown? Surely it had been installed on other airplanes.
The mechanics swapped engines freely
in the United Airlines maintenance base in San Francisco. You never knew where one might end up, half a world away one day and right behind your head the next. The situation was even more complicated than that, because whenever mechanics tore down one of those engines to service it, they switched parts with other engines. One of those spinning wheels may have been on half-a-dozen other engines at one time or another. Meticulous records of all the parts and pieces were meant to be kept. Where were those records now?

In fact, engine 451-243 was a collection of spare parts flying in close formation. And since June 23, 1972, when that engine was first installed on the right wing of a DC-10, it had been all over the place. Its internal parts had been changed and changed again. In reality, then, the engine itself, 451-243, had no unique identity. However, the components, once cast and forged and machined, were given serial numbers and did retain unique identities. You never knew for sure what atoms made up a given engine, but you knew that the atoms of a component remained an integral part of its personality. So to understand the engine that failed—to grasp how its beautiful workings could go so hideously wrong—we will ultimately have to understand those component parts.

Dvorak had been away from the cockpit for less than two minutes when he came back through first class, past Jerry Kennedy, the newly hired United pilot, and stood banging urgently on the door. As Brad Griffin watched, the door remained shut. Haynes was saying, “I wish they’d unlock that fuckin’ door. Pull the circuit breaker on that door and just unlock it, will ya?”

Fitch was at last able to open it, and Dvorak entered, pale and drawn, to announce, “Damage on the tail.”

“On the tail,” Haynes said. “That’s what I thought.”

Records asked, “You see it?”

“It’s not the wing,” Dvorak said, correcting Jan Brown’s slip of the tongue. “It’s the tail. Yeah, you can see it.”

Dvorak sat at his engineer’s console once again and buckled in at nearly a quarter to four in the afternoon. He keyed the microphone and told SAM, “Alright, I walked to the back and we got, ah, a lot of damage to the tail section that we could see through the window.”

The engineer on the line said, “Okay, ya, United Two Thirty-Two, ah, you have, ah, you have a lot of damage to the tail section.”

“Ah, the leading edge of the elevator is, ah, damaged, ah, it’s not . . .” And here he heaved a weary sigh. “I mean, ah, there’s damage there that I can see. I don’t know how much is . . . that I cannot see. I can see it on the leading edge. On the outer part.”

The man on the line said that other engineers were now listening in. Dvorak gave them a lengthy summary of what had happened so far, even as Haynes addressed the passengers, explaining that they would attempt an emergency landing at Sioux City and that his signal, before they met with the earth, would be the word
brace
, repeated three times.

At fourteen minutes to the hour, Fitch began the only left turn that the disabled plane was to make. While the crew had been unable to make left turns until then, he’d had twenty minutes of practice at steering the plane with the throttles, and this was his finest performance, his swan song. This crucial maneuver put 1819 Uniform on a southwesterly course direct to Sioux City at nearly the correct altitude to make the runway. It happened to be the wrong runway, though, one with a large number of fire engines parked on it and a big yellow
X
painted across the approach end to let pilots know that it was permanently closed.

As Brad Griffin listened to the captain’s announcement, he heard a roar of anxiety and despair rise from the coach cabin, like that from a crowd in a theater when the projector breaks in the middle of the movie. Rene Le Beau was coming up the starboard aisle, first through B-Zone, past Ruth Pearlstein in her bright-green dress, taking care of five-year-old Devon McKelvey beside her, then past the little girl’s brother Ryan, seven, sitting beside his mother Debbie.
Debbie and Ruth were tennis partners
. Le Beau passed on into first class. Brad Griffin noticed her because of her bright-red hair with the big blue bow in it, her startling youth. “I remember her walking backwards, telling people about the crash position. And her hands were shaking” as she held the briefing card. “She was so brave. And so scared.”

Now up in the cockpit, as the plane descended below nine thousand feet, Haynes asked Dvorak, “What did SAM say? ‘Good luck’?”

“He hasn’t said anything,” Dvorak responded.

“Okay, well, forget them,” Haynes said. “Tell ’em you’re leaving the air and you’re gonna come back up here and help us. And screw ’em.”

SAM called again, saying, “United Two Thirty-Two, one more time: No hydraulic quantity, is that correct?”

Dvorak said in frustration, “Affirmative-affirmative-affirmative!” More than twenty minutes had elapsed since he first reported that the craft had lost all hydraulic fluid.

After giving the passengers a ten-minute warning, Haynes discussed with the crew how to put the wheels down without hydraulics. They decided that the simplest procedure was to open the doors and let the landing gear fall out. Once that was done, Haynes said, “Okay, lock up and put everything away.” Then he said to himself, “Well, Mama, we’ll make those baseball games after all.”

When Haynes’s two sons were young, they played on Little League baseball teams. One day a friend of his who was the umpire for the local teams was unable to attend the games. Haynes found himself hastily learning the rules so that he could officiate. “I had a lot of fun and they were short on umpires, so I said I’d do the next one, and pretty soon I’m in it full time. I’ve been in it now for thirty years.” Now, in the grip of the emergency, he was expressing hope. The crew might land the plane safely and make it to those weekend games that were coming up at the height of the Little League season.

Records keyed his mike and asked the Sioux City tower, “Where’s the airport for Two Thirty-Two?”

“United Two Thirty-Two,” said Bachman, “the airport’s currently twelve o’clock and, ah, two-one miles.”

Bachman was unsure. Should he let the DC-10 wander at will, even over the city where it might kill people on the ground? Should he direct the craft to turn away from the city and risk upsetting the plane and causing it to crash before it reached the airport? Even if a turn didn’t compromise the plane’s stability, the crew had to steer past several electronics towers, some of them more than two thousand feet tall. If 1819 Uniform hit one of those towers while attempting a turn, the wreckage would fall all over Siouxland. Bachman turned to Zielezinski and said, “Make the call.”

Mark Zielezinski well knew that if anything went wrong, the responsibility would fall on him. “Kevin was a good controller for his experience level,” Zielezinski later said. “But it was the team work of all the controllers that pitched in to make Kevin’s job just a little bit easier. Kevin’s only real task was responding to the crew [of 1819 Uniform] and passing along information that they requested. There were no other aircraft he was dealing with. Those aircraft were being worked by my other radar controller, Jim Weifenbach, who was responsible for separating them from [1819 Uniform].” Weifenbach was bringing in the A-7s. “Sitting between and monitoring both positions,” Zielezinski went on, “I was able to feed Jim information on what was going on with the emergency aircraft. He was able to vector aircraft away from the emergency. When the one time came that actually required Kevin to make a decision, he turned to me and said ‘Make the call.’ If something would have happened, he could have easily said, ‘Mark told me to do it.’ ”

Zielezinski told Bachman to instruct United Flight 232 to turn. “After the fact,” Zielezinski recalled, “when I thought about it, it scared the crap out of me, because if they didn’t turn tight enough or [weren’t] able to stay above the towers, the wreckage would have been up in that area instead of the airport. Would I make that call again? Not sure. It was a call from my gut and experience as a pilot, but sitting on the ground, I had no assurance the turn would be tight enough.”