Seven years after Eastern Air Lines 66, Low Level Windshear detection systems were in their infancy but were installed in New Orleans at the time of this mishap. The crew of Pan Am 759 had been warned. The winds had gone from calm, to 8 knots in a minute, to 17 knots gusting to 23 only four minutes later. The crew was given a windshear alert. Their solution was to keep the airplane on the ground longer to build up speed and to takeoff with the air conditioning packs off to increase thrust. This may seem reckless but consider this: several aircraft had just taken off with full knowledge that there were thunderstorms in the area, including one on top of the airport. The NTSB concluded the captain's decision to take off was reasonable in light of the information available. We pilots, and our industry, simply didn't respect the fact that a microburst could far exceed the capabilities of our aircraft. Our knowledge has improved and this mishap would be avoided today by simply electing not to take off.
Everything here is from the references shown below, with a few comments in an alternate color.
Figure: "That day in Kenner," from New Orleans Times Picayune
Figure: Vertical Cross Section of Microburst Winds, from NTSB AAR 83-02, Figure 3.
[NTSB AAR 83-02, ¶1.1]
[NTSB AAR 83-02, ¶1.7]
[NTSB AAR 83-02, ¶2.2]
[NTSB AAR 83-02, ¶3.1, item 21.] The captain's decision to take off was reasonable in light of the information that was available to him.
[NTSB AAR 83-02, ¶3.2] The National Transportation Safety Board determines that the probable cause of the accident was the airplane's encounter during the lift-off and initial climb phase of flight with a micro-burst induced windshear which imposed a downdraft and a decreasing headwind, the effects of which the pilot would have had difficulty recognizing and reacting to in time for the airplane's descent to be arrested before its impact with trees. Contributing to the accident was the limited capability of current ground based low level windshear detection technology to provide definitive guidance for controllers and pilots for use in avoiding low level wind shear encounters."
New Orleans Times-Picayune, "That Day in Kenner," July 2007
NTSB Aircraft Accident Report, AAR-83/02, Pan American World Airways, Inc., Clipper 759, Boeing 727-235, N4737, New Orleans International Airport, Kenner Louisiana, July 9, 1982
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