Into The Weeds

Well, since this topic came up at some point last night, I figured it’s time to blog about it. On July 19th 1989, United Flight 232 was a DC-10 flying from Denver to Philadelphia via O’Hare. The crash of flight 232 is probably the most well-known american aviation disaster, due to the presence of film crews at the crash. What most people don’t know, however, is the full story of how the 185 survivors of the crash owe their lives to the extraordinary actions of the captain, the crew, and a DC-10 instructor that just happened to be deadheading as a passenger when the plane’s hydraulic systems all went into the weeds.

In subsequent reconstructions of the circumstances of the accident in flight simulators, no pilot, regardless of seniority, has succeeded in reproducing the flight crew’s achievement of maneuvering the aircraft as far as the runway, generally losing control in mid air.

The images are familiar: the video shot through a chainlink fence of a jetliner engulfed in flames cartwheeling down the runway at Sioux City, Iowa. The cause of the disaster was the catastrophic failure of the fan disk on the airliner’s tail-mounted engine. The engine assembly did not contain the debris, and all three of the airplane’s redundant hydraulic lines were severed, sending the plane’s entire hydraulic system into the weeds. Without any hydraulics, none of a plane’s control surfaces will work, pretty much making the plane impossible to fly.

Since the hydraulic lines were triply redundant, this was one of those failures that had been considered impossible by the aircraft’s manufacturer and engineers, and was not trained for in any flight simulators. The crew quickly realized that they had virtually no control over the plane, and their only method of steering and maintaining altitude was by clever manipulation of the remaining engines’ thrusts independently. At one point during the flight, a man by the name of Dennis Fitch offered his assistance to the flight crew. It just so happens that he was a DC-10 instructor and pilot who was deadheading as a passenger on the plane. He was able to offer much assistance in working the throttles to maintain control of the aircraft.

The CVR transcript from the flight is a must-read, and really completes the story. Some of my favorite excerpts follow:

[When Capt. Fitch enters the cockpit]
Captain Haynes:  My name's Al Haynes.
Captain Fitch:   Hi, Al.  Denny Fitch.
Captain Haynes:  How do you do, Denny?
Captain Fitch:   I'll tell you what.  We'll have a beer when this is
all done.
Captain Haynes:  Well, I don't drink, but I'll sure as hell have
one.  Little right turns, little right turns.

[Approaching for the crash landing]
Sioux City Approach:  United two thirty-two heavy, the wind's
currently at three six zero at one one three
sixty at eleven.  You're cleared to land on
any runway...
Captain Haynes:  [Laughter] Roger. [Laughter] You want to be
particular and make it a runway, huh?

Fitch and the crew were able to maneuver the plane just enough to get it to the runway, and actually touch down near the end, and on the center line. Unfortunately, due to the high airspeed and sink rate of the plane, a wing touched the ground and sent the plane into a somersault, breaking up the aircraft. It is believed that just getting the plane on the ground on the runway is what saved the 185 survivors of the crash (including the crew). An interesting footnote to the story, which I discovered in the Wikipedia article , is that Michael Matz, a passenger on the plane considered a hero for helping to pull children out of the flaming wreck, trained this year’s Kentucky Derby winner Barbaro.

Wikipedia article
CVR transcript
CVR audio excerpt near impact
Airdisaster.com article
Interview with Al Haynes