Delta Flight 191-The Microburst Story

August 2, 1985

Dallas-Fort Woth Int'l

L-1011-385

Stormy day at DFW, and Delta 191 was coming in to land. Captain Edward Connors warned Rudolph Price to watch his speed. "You're going to lose it all of a sudden." "Push it up, way up!" the engines then start to spooling up. He than yelled "That's it! Hang on to that son of a b*tch!" The aircraft then began to rapidly descend, and hit the ground, rolled onto Texas 114, and the left engine killed someone in a car when the engine hit it. It rolled into a water tank and fire balled, and the tail section of the plane spun off. 137 people were killed, including 1 on ground and 28 were injured, also including 1 on ground.

The troublesome approach
Delta Air Lines Flight 191 was a regularly scheduled Delta Air Lines domestic service from Fort Lauderdale, Florida to Los Angeles, via Dallas. In process of flying toward Blue Ridge Approach, at 17:43, Captain Connors asked tower that he wants to go around the storm cell. Except that, everything appeared to be normal. 17:46, the controller cleared the flight direct to Blue Ridge and instructed the flight crew to descend to 9,000 feet (2,700 m). At 17:51, the second officer commented, "Looks like it's raining over Fort Worth." At 17:51, the Fort Worth ARTCC controller transferred the flight to DFW Airport Approach Control, which cleared the flight to descend to 7,000 feet (2,100 m). Two minutes later, the controller asked the Delta flight to deviate by ten degrees and to slow their airspeed to 180 knots (210 mph). The flight acknowledged the request. As the flight descended, the crew prepared the aircraft for landing. At 17:56, the feeder controller cleared the flight down to 5,000 feet (1,500 m). Nine seconds later, the controller announced that there was rain north of the airport, and that the airport would be using instrument landing system (ILS) approaches. At 18:00, Flight 191 was instructed to slow to 170 knots (200 mph) and to turn to heading 270°. Flight 191 was instructed to descend to 3,000 feet (910 m) at 18:01, One minute later, the approach controller turned the flight toward Runway 17L and cleared them for an ILS approach at or above 2,300 feet (700 m). Half a minute afterward, the controller asked the flight to reduce their speed to 160 knots (180 mph), which the flight crew acknowledged. At 18:03, the controller advised that there are some variable winds at north of the DFW. At 18:03, the approach controller once again asked Flight 191 to reduce its speed, this time to 150 knots (170 mph), and then handed the flight over to the tower controller.

Crash
At 18:04, The Delta Crew got the updated weather report that there are the wind gusts up to 15 knots and acknowleged it. Flight crew started to lower gears and flaps for landing. At 18:05, captine called out that they were at 1,000 ft. Few seconds later, captain told first official to watch his airspeed carefully. At that time, CVR(Cockpit Voice Recorder) recorded the rain hitting hard on cockpit. As the aircraft's speed became too low and closer to stall speed, the captain warned Price, "You're gonna lose it all of a sudden, there it is." At 18:05, the captain told Price, "Push it up, push it way up." Several second later, the CVR recorded the sound of the engines spooling up. Connors then said, "That's it." At 18:05, Connors exclaimed, "Hang on to the son of a b*tch!" From this point, the aircraft began a descent from which it never recovered. The angle of attack (AOA) was over 30° and began to vary wildly over the next few seconds. The pitch angle began to sink and the aircraft started descending below the glideslope. It was literally stalling at low altitude. Then at 18:06, because of the excessive sink rate at low altitude (sinking at 50 ft. per second), the GPWS alarm started to sound. The captain responded by declaring "TOGA", aviation shorthand for the order to abort a landing by taking off and going around. The first officer responded by pulling up and raising the nose of the aircraft, which slowed but did not stop the plane's descent. At 18:06, still descending at a rate of approximately 10 feet per second., the aircraft's landing gear made contact with a plowed field 6,340 feet north of the runway and 360 feet east of the runway centerline. Remaining structurally intact, Flight 191 remained on the ground while rolling at high speed across the farmland. The main landing gear left shallow depressions in the field that extended for 240 feet before disappearing and reappearing a couple times as the aircraft approached Texas State Highway 114. The aircraft bounced and struck street lights and its nose gear hit the highway 114's roadway hard. The left engine impected a car and killed the driver. As it continued to roll down after passing highway 114, it struck more street lights and some of its parts from engine and horizontal stabilizers were fell off. The fires were reported on wing root and started to enter cabin while the aircraft is in motion. At 18:07, the aircraft's wild ride in grass ended when it crashed into pair of water tank and exploded, causing the tail part to spun away from main fuselage and making big fireball.

After the Crash
Within the minute of crash, all firefighting units in DFW were dispatched and local fire units responded within 5 minutes. Within 10 minutes, all fires were safely under control. Paramedics also arrived within 5 minutes of crash and on-site triage was formed. Most of the people who survived were sat in tail of the aircraft. No one at front of row 20 survived. Between the 20-33, where aircraft's tail section saparated, all but 8 people were killed. From behind the row 34, 20 people survived and 17 were killed. This could have been far worse crash if the aircraft was full of passengers.

What Lessons had been Learned from it?
- New policies, specific training, and procedures for avoiding and escaping low-altitude wind shear was added.

- Microburst with lack of radar technology and training about it were the factors caused the accident.

- The aircraft warnings on windshear in commercial airliners were mandated by FAA.

- More quicker response time in case of emergency in airport by adopting automated voice notification system.

- Better detailed radar dopplar that can detect microburst near airport to be installed as well as mandatory Dopplar Radar in comercial aircraft, located I'm the nose of the plane.

< Microburst is the violent wind gust that hits the ground hard straight from sky and after hitting ground, bounces into random various direction, causing violent turbulence that can bring down planes without notice.>