Page:Delta-Air-Lines-Flight-191-NTSB-Final-Report-AAR-86-05.pdf/5



Adopted: August 15, 1986

On August 2, 1985, at 1805:52 central daylight time, Delta Air Lines flight 191, a Lockheed L-1011-385-1, N726DA, crashed while approaching to land on runway 17L at the Dallas/Fort Worth International Airport, Texas. While passing through the rain shaft beneath a thunderstorm, flight 191 entered a microburst which the pilot was unable to traverse successfully. The airplane struck the ground about 6,300 feet north of the approach end of runway 17L, hit a car on a highway north of the runway killing the driver, struck two water tanks on the airport, and broke apart. Except for a section of the airplane containing the aft fuselage and empennage, the remainder of the airplane disintegrated during the impact sequence, and a severe fire erupted during the impact sequence. Of the 163 persons aboard, 134 passengers and crewmembers were killed; 26 passengers and 3 cabin attendants survived.

The National Transportation Safety Board determines that the probable causes of the accident were the flightcrew's decision to inítiate and continue the approach into a cumulonimbus cloud which they observed to contain visible lightning; the lack of specific guidelines, procedures, and training for avoiding and escaping from low-altitude wind shear; and the lack of definitive, real-time wind shear hazard information. This resulted in the aircraft's encounter at low altitude with a microburst-induced, severe wind shear from a rapidly developing thunderstorm located on the final approach course.

1.1

On August 2, 1985, Delta Air Lines (Delta) flight 191 was a regularly scheduled passenger flight between Fort Lauderdale, Florida, and Los Angeles, California, with an en route stop at the Dallas/Fort Worth International Airport, Texas (DFW Airport). Flight 191, a Lockheed L-1011-385-1 airplane, departed Fort Lauderdale on an instrument flight rules (IFR) flight plan with 152 passengers and a crew of 11 on board at 1510 eastern daylight time. The DFW Airport terminal weather forecast contained in the flightcrew's dispatch document package stated, in part, that there was a possibility of widely scattered rain showers and thunderstorms, becoming isolated after 2000 central daylight time. The dispatch package also contained company Metro Alert No. T87, valid to 2100, which stated that "an area of isolated thunderstorms is expected over Oklahoma and northern and northeastern Texas... a few isolated tops to above