Remembering Captain Al Haynes

By Jeff Marcus, Chief, NTSB Safety Recommendations Division

This past Sunday, August 25, 2019, Captain Al Haynes died a week shy of his 88th birthday. Captain Haynes was a remarkable pilot who, 30 years ago last month, brought United Airlines flight 232 to an emergency landing in Sioux City, Iowa, with no means of control except the ability to vary the thrust produced by the airplane’s two engines (the DC-10’s third engine had experienced an uncontained engine failure). Although 111 passengers ultimately perished in the accident, the actions of Captain Haynes and the other crewmembers saved the lives of 184 others on the flight.

The sequence of events started when the airplane’s central engine in the tail failed, sending heavy, high-speed shrapnel spraying through the rear of the airplane. The shrapnel cut all three of the airplane’s hydraulic lines and all hydraulic pressure was lost. This left no way for the pilots to control the airplane—at least, no way intentionally designed for that purpose. Hydraulic pressure was needed to move the airplane’s control surfaces and allow it to turn, climb or descend in response to pilot input, and to configure the airplane for landing by extending the flaps.

After the engine failure, the airplane started banking to the right and its nose dropped. The crew tried to stop the bank and bring the nose up, but the airplane did not respond. The only controls that worked were the throttles for the remaining two engines, one on each wing. By varying how much power each engine produced—that is, applying differential thrust—the pilots were able to stop the turn and bring the airplane level.

The plane pulled right, and slowly oscillated vertically in what is called a phugoid cycle, losing approximately 1,500 feet of altitude with each cycle. Among the passengers on the flight was Captain Dennis Fitch, a United pilot and training check airman, who came to the cockpit and offered Captain Haynes any help that he could provide. Captain Haynes welcomed Captain Fitch’s help.

Captain Fitch began to apply differential thrust, and that way, regained some control of the airplane. He was able to minimize the phugoid and gain some directional control, although the airplane could only turn to the right. The decision was made to make an emergency landing at the airport in Sioux City, Iowa.

The crew was able to use differential thrust alone to control the airplane’s direction of travel and descent, and line up the DC-10 with the runway. But, with no hydraulics, the flaps could not be extended. When the DC-10 was designed and approved, the total loss of hydraulic-powered flight controls was considered so unlikely that there was no need to develop and approve a procedure to deal with such a situation. Because flaps control both the minimum required airspeed and sink rate, however, the flight 232 crew could control neither.

Just prior to landing, the airplane was going 220 knots and descending at 1,850 feet per minute, well above the normal targets of 140 knots and a 300-feet-per-minute descent. As the plane touched down, the right wing tip hit the runway first, and the plane began to break up and catch fire, ultimately resulting in the fatalities of 111 people. For 184 others, Captain Haynes and his flight crew are credited with their improbable deliverance from an unlikely accident cause.

In our investigation of this accident, we pointed out that the interaction of the pilots, including the check airman, during the emergency showed the value of crew resource management (CRM – then known as cockpit resource management) training, which had been practiced at United Airlines for a decade. Ten years before the United flight 232 accident, we recommended that CRM training be required for all airline flight crews.

Flight simulator reenactments of the accident airplane’s flight profile carried out as part of our investigation revealed that it was virtually impossible to control all parameters simultaneously needed to land safely at a predetermined point. After observing the performance of a control group of DC-l0-qualified pilots in the simulator, we concluded that Captain Haynes’s damaged DC-10 airplane, although flyable, could not have been successfully landed on a runway after the loss of all hydraulic flight controls, and that, under the circumstances, United flight 232’s flightcrew reacted commendably and beyond reasonable expectations.

But the benefits of CRM training were clear. The flight crew, lead by Captain Haynes, used CRM to deal with a situation considered so unlikely that there were no procedures or training on how to respond. When talking about the accident later, Captain Haynes said, “If I hadn’t used CRM, if we had not let everybody put their input in, it’s a cinch we wouldn’t have made it.”

Although he always denied that he was a hero, Captain Haynes was the right man at the right time for an event considered to be so unlikely that it was virtually impossible. Thirty years after that accident, and mere days after Captain Haynes’s death, we at the NTSB remember how his CRM practice saved over half the people on United flight 232. Aviation is safer the world over thanks to Captain Haynes.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s